BANK OF AMERICA
                    National Trust and Savings Association
                            BUSINESS LOAN AGREEMENT



This Agreement dated as of August 1, 1995, is among Bank of American National
Trust and Savings Association (the "Bank"), Salick Health Care, Inc. ("Salick"),
USHAWL, Inc. ("USHAWL"), Century Dialysis Corporation ("Century"), Comprehensive
Cancer Centers, Inc., a California Corporation ("CCC"), Ambulatory Diagnostic
Services, Inc. ("ADS"), Aurora Medical Supplies Inc., a California Corporation
("Aurora"), Comprehensive Cancer Centers, Inc.-Philadelphia ("CCC-Penn"),
Comprehensive Cancer Centers, Inc., Kansas City ("CCC-Kansas"), SHC
Laboratories, Inc. ("SHC"), and Comprehensive Cancer Centers-West Valley, Inc.
("CCC-West") (Salick, USHAWL, Century, CCC, ADS, Aurora, CCC-Penn, CCC-Kansas,
SHC, and CCC-West are sometimes referred to collectively as the "Borrowers" and
individually as the "Borrower").

1.   FACILITY NO. 1:  LINE OF CREDIT AMOUNT AND TERMS

1.1  Line of Credit Amount.

(a)  During the availability period described below, the Bank will provide a
     line of credit ("Facility No. 1") to the Borrowers.  The amount of the line
     of credit (the "Facility No. 1 Commitment") is Eighty Million Dollars
     ($80,000,000).

(b)  This is a revolving line of credit with a within line facility for letters
     of credit.  During the availability period, the Borrowers may repay
     principal amounts and reborrow them.

(c)  The Borrowers agree not to permit the outstanding principal balance of the
     line of credit plus the outstanding amounts of any letters of credit,
     including amounts drawn on letters of credit and not yet reimbursed, to
     exceed the Facility No. 1 Commitment.

1.2  Availability Period.  The line of credit is available between the date of
this Agreement and July 1, 1998 (the "Expiration Date") unless any Borrower is
in default.

1.3  Interest Rate.

(a)  Unless the Borrowers elect an optional interest rate as described below,
     the interest rate is the Bank's Reference Rate.

(b)  The Reference Rate is the rate of interest publicly announced from time to
     time by the Bank in San Francisco, California, as its Reference Rate.  The
     Reference Rate is set by the Bank

                                 EXHIBIT 4 (a)

 
     based on various factors, including the Bank's costs and desired return,
     general economic conditions and other factors, and is used as a reference
     point for pricing some loans.  The Bank may price loans to its customers
     at, above, or below the Reference Rate.  Any change in the Reference Rate
     shall take effect at the opening of business on the day specified in the
     public announcement of a change in the Bank's Reference Rate.

1.4  Repayment Terms.

(a)  The Borrowers will pay interest on July 1, 1995, and then monthly
     thereafter until payment in full of any principal outstanding under this
     line of credit.

(b)  The Borrowers will repay in full all principal and any unpaid interest or
     other charges outstanding under this line of credit no later than the
     Expiration Date.  Any amount bearing interest at an optional interest rate
     (as described below) may be repaid at the end of the applicable interest
     period, which shall be no later than the Expiration Date.

1.5  Optional Interest Rates.  Instead of the interest rate based on the Bank's
Reference Rate, the Borrowers may elect to have all or portions of the line of
credit (during the availability period) bear interest at the rate(s) described
below during an interest period agreed to by the Bank and the Borrowers.  Each
interest rate is a rate per year.  Interest will be paid on the last day of each
interest period, and, if the interest period is longer than one month, then on
the first day of each month during the interest period.  At the end of any
interest period, the interest rate will revert to the rate based on the
Reference Rate, unless the Borrowers have designated another optional interest
rate for the portion.  Upon the occurrence of an event of default under this
Agreement, the Bank may terminate the availability of optional interest rates
for interest periods commencing after the default occurs.

1.6  Short Term Fixed Rate.  The Borrower may elect to have all or portions of
the principal balance of the line of credit bear interest at the Short Term
Fixed Rate, subject to the following requirements:

(a)  The "Short Term Fixed Rate" means the Short Term Base Rate plus thirty five
     one hundredths (.35) percentage point.

(b)  The "Short Term Base Rate" means the fixed interest rate per annum,
     determined solely by the Bank on the first day of applicable interest
     period for the Short Term Fixed Rate portion, as the rate at which the Bank
     would be able to borrow funds in the Money Market in the amount of the
     Short Term Fixed Rate portion and with an interest and principal payment
     schedule equal to the Short Term Fixed Rate portion and for a

                                 EXHIBIT 4 (a)

 
     term equal to the applicable interest period.  The Short Term Base Rate
     shall include adjustments for reserve requirements, federal deposit
     insurance, and any other similar adjustment which the Bank deems
     appropriate.  The Short Term Base Rate is the Bank's estimate only and the
     Bank is under no obligation to actually purchase or match funds for any
     transaction.

(c)  "Money Market" means one or more wholesale funding markets available to the
     Bank, including domestic negotiable certificates of deposit, eurodollar
     deposits, bank deposit notes or other appropriate money market instruments
     selected by the Bank.

(d)  The interest period during which the Short Term Fixed Rate will be in
     effect will be no shorter than 30 days and no longer than one year.

(e)  Each Short Term Fixed Rate portion will be for an amount not less than Five
     Hundred Thousand Dollars ($500,000).

(f)  Any portion of the principal balance of the line of credit already bearing
     interest at the Short Term Fixed Rate will not be converted to a different
     rate during its interest period.

(g)  Each prepayment of a Short Term Fixed Rate portion, whether voluntary, by
     reason of acceleration or otherwise, will be accompanied by the amount of
     accrued interest on the amount prepaid, and a prepayment fee equal to the
     amount (if any) by which:

     (i)  the additional interest which would have been payable on the amount
          prepaid had it not been prepaid, exceeds

     (ii) the interest which would have been recoverable by the Bank by placing
          the amount prepaid on deposit in the Money Market for a period
          starting on the date on which it was prepaid and ending on the last
          day of the interest period for such portion (or the scheduled payment
          date for the amount prepaid, if earlier).

1.7  LIBOR Rate.  The Borrower may elect to have all or portions of the
principal balance bear interest at the LIBOR Rate plus thirty five one
hundredths (.35) percentage point.

Designation of a LIBOR Rate portion is subject to the following requirements:

(a)  The interest period during which the LIBOR Rate will be in effect will be
     30, 60, 90, 180 or 365 days.  The last day of the interest period will be
     determined by the Bank using the practices of the London inter-bank market.

                                 EXHIBIT 4 (a)

 
(b)  Each LIBOR Rate portion will be for an amount not less than Five Hundred
     Thousand Dollars ($500,000).

(c)  The Borrower shall irrevocably request a LIBOR Rate portion no later than
     9:00 a.m. San Francisco time three (3) banking days before the commencement
     of the interest period.

(d)  The "LIBOR Rate" means the interest rate determined by the following
     formula, rounded upward to the nearest 1/100 of one percent.  (All amounts
     in the calculation will be determined by the Bank as of the first day of
     the interest period.)

          LIBOR Rate =                                London Rate
                                             ---------------------------
                                             (1.00 - Reserve Percentage)

     Where,

     (i)  "London Rate" means the interest rate (rounded upward to the nearest
          1/16th of one percent) at which the Bank's London Branch, London,
          Great Britain, would offer U.S. dollar deposits for the applicable
          interest period to other major banks in the London inter-bank market
          at approximately 11:00 a.m. London time two (2) banking days before
          the commencement of the interest period.

     (ii) "Reserve Percentage" means the total of the maximum reserve
          percentages for determining the reserves to be maintained by member
          banks of the Federal Reserve System for Eurocurrency Liabilities, as
          defined in Federal Reserve Board Regulation D, rounded upward to the
          nearest 1/100 of one percent.  The percentage will be expressed as a
          decimal, and will include, but not be limited to, marginal, emergency,
          supplemental, special, and other reserve percentages.

(e)  The Borrower may not elect a LIBOR Rate with respect to any principal
     amount which is scheduled to be repaid before the last day of the
     applicable interest period.

(f)  Any portion of the principal balance already bearing interest at the LIBOR
     Rate will not be converted to a different rate during its interest period.

(g)  Each prepayment of a LIBOR Rate portion, whether voluntary, by reason of
     acceleration or otherwise, will be accompanied by the amount of accrued
     interest on the amount prepaid and a prepayment fee as described below.  A
     "prepayment" is a payment of an amount on a date earlier than the scheduled
     payment date for such amount as required by this Agreement.  The prepayment
     fee shall be equal to the amount (if any) by which:

                                 EXHIBIT 4 (a)

 
     (i)  the additional interest which would have been payable during the
          interest period on the amount prepaid had it not been prepaid, exceeds

     (ii) the interest which would have been recoverable by the Bank by placing
          the amount prepaid on deposit in the London inter-bank market for a
          period starting on the date on which it was prepaid and ending on the
          last day of the interest period for such portion (or the scheduled
          payment date for the amount prepaid, if earlier).

(h)  The Bank will have no obligation to accept an election for a LIBOR Rate
     portion if any of the following described events has occurred and is
     continuing:

     (i)  Dollar deposits in the principal amount, and for periods equal to the
          interest period of a LIBOR Rate portion are not available in the
          London inter-bank market; or

     (ii) the LIBOR Rate does not accurately reflect the cost of a LIBOR Rate
          portion.

1.8  Letters of Credit.  This line of credit may be used for financing.

     (i)  standby letters of credit with a maximum maturity of one year but not
          to extend more than six months beyond the Expiration Date.

     (ii) The amount of standby letters of credit outstanding at any one time,
          (including amounts drawn on standby letters of credit and not yet
          reimbursed) may not exceed Ten Million Dollars ($10,000,000).

Each Borrower agrees:

(a)  any sum drawn under a standby letter of credit may, at the option of the
     Bank, be added to the principal amount outstanding under this Agreement.
     The amount will bear interest and be due as described elsewhere in this
     Agreement.

(b)  if there is a default under this Agreement, to immediately prepay and make
     the Bank whole for any outstanding standby letters of credit.

(c)  The issuance of any standby letter of credit and any amendment to a standby
     letter of credit is subject to the Bank's written approval and must be in
     form and content satisfactory to the Bank and in favor of a beneficiary
     acceptable to the Bank.

(d)  to sign the Bank's form Application and Agreement for Standby Letter of
     Credit.

                                 EXHIBIT 4 (a)

 
(e)  to pay any issuance and/or other fees that the Bank notifies the Borrowers
     will be charged for issuing and processing standby letters of credit for
     the Borrowers.

(f)  to allow the Bank to automatically charge its checking account for
     applicable fees, discounts, and other charges.

(g)  to pay the Bank a non-refundable fee equal to thirty five one hundredths
     percent (.35%) per annum of the outstanding undrawn amount of each standby
     letter of credit, payable quarterly in advance, calculated on the basis of
     the face amount outstanding on the day the fee is calculated.

(h)  not to issue any standby letters of credit to the State of California Self
     Insurance Plans.

2.   FACILITY NO. 2:  TERM LOAN AMOUNT AND TERMS

2.1  Outstanding Term Loan.  There is outstanding from the Bank to the Borrowers
a term loan in the original principal amount of Five Million Dollars
($5,000,000).  This term loan is currently subject to the terms and conditions
of the Business Loan Agreement dated January 1, 1993.  As of the date of the
Agreement, the term loan shall be deemed to be outstanding as Facility No. 2
under this Agreement, and shall be subject to all the terms and conditions
stated in this Agreement.

2.2  Interest Rate.  The interest rate is 6.85% per year.

2.3  Repayment Terms.

(a)  The Borrowers will pay all accrued but unpaid interest on the twenty-sixth
     day of each month and upon payment in full of the principal of this loan.

(b)  The Borrowers will repay principal in thirty-eight (38) successive monthly
     installments of Eighty Three Thousand Three Hundred Thirty Three and No/100
     Dollars ($83,333.00) starting June 26, 1995.  On August 26, 1998, the
     Borrowers will repay the remaining principal balance plus any interest then
     due.

2.4  Prepayments.

(a)  The Borrowers may prepay the loan in full or in part at any time in an
     amount not less than Five Hundred Thousand Dollars ($500,000).  The
     Borrowers will give the Bank irrevocable written notice of the Borrowers'
     intention to make the prepayment, specifying the date and amount of the
     prepayment.  The notice must be received by the Bank at least 5 banking
     days in advance of the prepayment.  The prepayment will be applied to the
     most remote installment of principal due under this Agreement.

                                 EXHIBIT 4 (a)

 
(b)  Each prepayment, whether voluntary, by reason of acceleration or otherwise,
     will be accompanied by the amount of accrued interest on the amount
     prepaid, and the prepayment fee described below.

(c)  The prepayment fee will be the sum of fees calculated separately for each
     Prepaid Installment, as follows:

     (i)  The Bank will first determine the amount of interest which would have
          accrued each month for the Prepaid Installment had it remained
          outstanding until the applicable Original Payment Date, using the loan
          rate specified above;

     (ii) The Bank will then subtract from each monthly interest amount
          determined in (i), above, the amount of interest which would accrue
          for that Prepaid Installment if it were reinvested from the date of
          prepayment through the Original Payment Date, using the following
          rate:

          (A)  If the Original Payment Date is more than 5 years after the date
               of prepayment:  the Treasury Rate plus one-quarter of one
               percentage point;

          (B)  If the Original Payment Date is 5 years or less after the date of
               prepayment:  the Money Market Rate.

    (iii) If (i) minus (ii) for the Prepaid Installment is greater than zero the
          Bank will discount the monthly differences to the date of prepayment
          by the rate used in (ii) above. The sum of the discounted monthly
          differences is the prepayment fee for that Prepaid Installment.

     (iv) The following definitions will apply to the calculation of the
          prepayment fee:

          "Money Market" means the domestic certificate of deposit market, the
          eurodollar deposit market or other appropriate money market selected
          by the Bank.

          "Money Market Rate" means the fixed interest rate per annum which the
          Bank determines could be obtained by reinvesting a specified Prepaid
          Installment in the Money Market from the date of prepayment through
          the Original Payment Date.

          "Original Payment Dates" means the dates on which principal of the
          loan would have been paid if there had been no prepayment.  If a
          portion of the principal would have been paid later than the end of
          the interest period in effect at the time of prepayment, then the
          Original

                                 EXHIBIT 4 (a)

 
          Payment Date for that portion will be the last day of the interest
          period.

          "Prepaid installment" means the amount of the prepaid principal of the
          loan which would have been paid on a single Original Payment Date.

          "Treasury Rate" means the interest rate yield for U.S. Government
          Treasury Securities which the Bank determines could be obtained by
          reinvesting a specified Prepaid Installment in such securities from
          the date of prepayment through the Original Payment Date.

     (v)  The Bank may adjust the Treasury Rate and Money Market Rate to reflect
          the compounding, accrual basis, or other costs of the loan.  Each of
          the rates is the Bank's estimate only and the Bank is under no
          obligation to actually reinvest any prepayment.  The rates will be
          based on information from either the Telerate or Reuters information
          services, The Wall Street Journal, or other information sources the
                    -----------------------                                  
          Bank deems appropriate.

3.   FACILITY NO. 3:  TERM LOAN AMOUNT AND TERMS

3.1  Outstanding Term Loan.  There is outstanding from the Bank to the Borrowers
a term loan in the original principal amount of Five Million Dollars
($5,000,000).  This term loan is currently subject to the terms and conditions
of the Business Loan Agreement dated January 1, 1993.  As of the date of this
Agreement, the term loan shall be deemed to be outstanding as Facility No. 3
under this Agreement, and shall be subject to all the terms and conditions
stated in this Agreement.

3.2  Interest Rate.  The interest rate is 8.62% per year.

3.3  Repayment Terms.

(a)  The Borrowers will pay all accrued but unpaid interest on the first day of
     each month and upon payment in full of the principal of this loan.

(b)  The Borrowers will repay principal in forty-nine (49) successive monthly
     installments of Eighty Three Thousand Three Hundred Thirty Three and 33/100
     Dollars ($83,333.33) starting July 1, 1995.  On August 2, 1999, the
     Borrowers will repay the remaining principal balance plus any interest then
     due.

3.4  Prepayments.

(a)  The Borrowers may prepay the loan in full or in part at any time in an
     amount not less than Five Hundred Thousand Dollars ($500,000).  The
     Borrowers will give the Bank irrevocable

                                 EXHIBIT 4 (a)

 
     written notice of the Borrowers' intention to make the prepayment,
     specifying the date and amount of the prepayment.  The notice must be
     received by the Bank at least 5 banking days in advance of the prepayment.
     The prepayment will be applied to the most remote installment of principal
     due under this Agreement.

(b)  Each prepayment, whether voluntary, by reason of acceleration or otherwise,
     will be accompanied by the amount of accrued interest on the amount
     prepaid, and the prepayment fee described below.

(c)  The prepayment fee will be the sum of fees calculated separately for each
     Prepaid Installment, as follows:

     (i)  The Bank will first determine the amount of interest which would have
          accrued each month for the Prepaid Installment had it remained
          outstanding until the applicable Original Payment Date, using the loan
          rate specified above;

     (ii) The Bank will then subtract from each monthly interest amount
          determined in (i), above, the amount of interest which would accrue
          for that Prepaid Installment if it were reinvested from the date of
          prepayment through the Original Payment Date, using the following
          rate:

          (A)  If the Original Payment Date is more than 5 years after the date
               of prepayment:  the Treasury Rate plus one-quarter of one
               percentage point;

          (B)  If the Original Payment Date is 5 years or less after the date of
               prepayment:  the Money Market Rate.

    (iii) If (i) minus (ii) for the Prepaid Installment is greater than zero,
          the Bank will discount the monthly differences to the date of
          prepayment by the rate used in (ii) above.  The sum of the discounted
          monthly differences is the prepayment fee for that Prepaid
          Installment.

     (iv) The following definitions will apply to the calculation of the
          prepayment fee:

          "Money Market" means the domestic certificate of deposit market, the
          eurodollar deposit market or other appropriate money market selected
          by the Bank.

          "Money Market Rate" means the fixed interest rate per annum which the
          Bank determines could be obtained by reinvesting a specified Prepaid
          Installment in the Money market from the date of prepayment through
          the Original

                                 EXHIBIT 4 (a)

 
          Payment Date.

          "Original Payment Dates" means the dates on which principal of the
          loan would have been paid if there had been no prepayment.  If a
          portion of the principal would have been paid later than the end of
          the interest period in effect at the time of prepayment, then the
          Original Payment Date for that portion will be the last day of the
          interest period.

          "Prepaid Installment" means the amount of the prepaid principal of the
          loan which would have been paid on a single Original Payment Date.

          "Treasury Rate" means the interest rate yield for U.S. Government
          Treasury Securities which the Bank determines could be obtained by
          reinvesting a specified Prepaid Installment in such securities from
          the date of prepayment through the Original Payment Date.

     (v)  The Bank may adjust the Treasury Rate and Money Market Rate to reflect
          the compounding, accrual basis, or other costs of the loan.  Each of
          the rates is the Bank's estimate only and the Bank is under no
          obligation to actually reinvest any prepayment.  The rates will be
          based on information from either the Telerate or Reuters information
          services, The Wall Street Journal, or other information sources the
                    -----------------------                                  
          Bank deems appropriate.

4.   FEES AND EXPENSES

4.1  Unused Commitment Fee.  The Borrowers agree to pay a fee on any difference
between the Facility No. 1 Commitment and the amount of credit the Borrowers
actually use, determined by the weighted average loan balance maintained during
the specified period.  The fee will be calculated at .10% per year.  This fee is
due on June 30, 1995, and quarterly thereafter until the expiration of the
availability period.

4.2  Expenses.  The Borrowers agree to reimburse the Bank for any expenses it
incurs in the preparation of this Agreement and any agreement or instrument
required by this Agreement up to a maximum of One Thousand Dollars ($1,000).
Expenses include, but are not limited to, reasonable attorneys' fees, including
any allocated costs of the Bank's in-house counsel.

5.   DISBURSEMENTS, PAYMENTS AND COSTS

5.1  Requests for Credit.  Each request for an extension of credit will be made
in writing in a manner acceptable to the Bank, or by another means acceptable to
the Bank.

                                 EXHIBIT 4 (a)

 
5.2  Disbursements and Payments.  Each disbursement by the Bank and each payment
by the Borrowers will be:

(a)  made at the Bank's branch (or other location) selected by the Bank from
     time to time;

(b)  made for the account of the Bank's branch selected by the Bank from time to
     time;

(c)  made in immediately available funds, or such other type of funds selected
     by the Bank;

(d)  evidenced by records kept by the Bank.  In addition, the Bank may, at its
     discretion, require the Borrowers to sign one or more promissory notes.

5.3  Telephone Authorization.

(a)  The Bank may honor telephone instructions for advances or repayments or for
     the designation of optional interest rates given by any one of the
     individual signer(s) of this Agreement or a person or persons authorized by
     any one of the signer(s) of the Agreement.

(b)  Advances will be deposited in and repayments will be withdrawn from
     Salick's account number 14176-02801, or such other accounts with the Bank
     as designated in writing by the Borrowers.

(c)  The Borrowers will provide written confirmation to the Bank of any
     telephone instructions within 30 days.  If there is a discrepancy and the
     Bank has already acted on the telephone instructions, the telephone
     instructions will prevail over the written confirmation.

(d)  The Borrowers indemnify and excuse the Bank (including its officers,
     employees, and agents) from all liability, loss, and costs in connection
     with any act resulting from telephone instructions it reasonable believes
     are made by any individual authorized by the Borrowers to give such
     instructions.  This indemnity and excuse will survive this Agreement's
     termination.

5.4  Direct Debit (Pre-Billing).

(a)  The Borrowers agree that the Bank will debit Salick's deposit account
     number 14176-02801 (the "Designated Account") on the date each payment of
     principal under Facility No. 2 and Facility No. 3 becomes due and on the
     date any interest and any fees from the Borrowers becomes due (the "Due
     Date").  If the Due Date is not a banking day, the Designated Account will
     be debited on the next banking day.

                                 EXHIBIT 4 (a)

 
(b)  Approximately 10 days prior to each Due Date, the Bank will mail to the
     Borrowers a statement of the amounts that will be due on that Due Date (the
     "Billed Amount"). The calculation will be made on the assumption that no
     new extensions of credit or payments will be made between the date of the
     billing statement and the Due Date, and that there will be no changes in
     the applicable interest rate.

(c)  The Bank will debit the Designated Account for the Billed Amount,
     regardless of the actual amount due on that date (the "Accrued Amount").
     If the Billed Amount debited to the Designated Account differs from the
     Accrued Amount the discrepancy will be treated as follows:

     (i)  If the Billed Amount is less than the Accrued Amount, the Billed
          Amount for the following Due Date will be increased by the amount of
          the discrepancy.  The Borrowers will not be in default by reason of
          any such discrepancy.

     (ii) If the Billed Amount is more than the Accrued Amount, the Billed
          Amount for the following Due Date will be decreased by the amount of
          the discrepancy.

          Regardless of any such discrepancy, interest will continue to accrue
          based on the actual amount of principal outstanding without
          compounding.  The Bank will not pay the Borrowers interest on any
          overpayment.

(d)  The Borrowers will maintain sufficient funds in the Designated Account to
     cover each debit.  If there are insufficient funds in the Designated
     Account on the date the Bank enters any debit authorized by this Agreement,
     the debit will be reversed.

5.5  Banking Days.  Unless otherwise provided in this Agreement, a banking day
is a day other than a Saturday or a Sunday on which the Bank is open for
business in California.  For amounts bearing interest at an LIBOR Rate a banking
day is a day other than a Saturday or a Sunday on which the Bank is open for
business in California, New York and London and dealing in offshore dollars.
All payments and disbursements which would be due on a day which is not a
banking day will be due on the next banking day.  All payments received on a day
which is not a banking day will be applied to the credit on the next banking
day.

5.6  Taxes.  The Borrowers will not deduct any taxes from any payments they make
to the Bank.  If any government authority imposes any taxes on any payments made
by the Borrowers, the Borrowers will pay the taxes and will also pay to the
Bank, at the time interest is paid, any additional amount which the Bank
specifies as necessary to preserve the after-tax yield the Bank

                                 EXHIBIT 4 (a)

 
would have received if such taxes had not been imposed.  Upon request by the
Bank, the Borrowers will confirm that they have paid the taxes by giving the
Bank official tax receipts (or notarized copies) within 30 days after the due
date.  However, the Borrowers will not pay the Bank's net income taxes.

5.7  Additional Costs.  The Borrowers will pay the Bank, on demand, for the
Bank's costs or losses arising from any statute or regulation, or any request or
requirement of a regulatory agency which is applicable to all national banks or
a class of all national banks.  The costs and losses will be allocated to the
loan in a manner determined by the Bank, using any reasonable method.  The costs
include the following:

(a)  any reserve or deposit requirements; and

(b)  any capital requirements relating to the Bank's assets and commitments for
     credit.

5.8  Interest Calculation.  Except as otherwise stated in this Agreement, all
interest and fees, if any, will be computed on the basis of a 360-day year and
the actual number of days elapsed.  This results in more interest or a higher
fee than if a 365-day year is used.

5.9  Interest on Late Payments.  At the Bank's sole option in each instance, any
amount not paid when due under this Agreement (including interest) shall bear
interest from the due date at the Bank's Reference Rate plus two (2.0)
percentage points.  This may result in compounding of interest.

5.10 Default rate.  Upon the occurrence and during the continuation of any
default under this Agreement, advances under this Agreement will at the option
of the Bank bear interest at a rate per annum which is three (3.0) percentage
points higher than the rate of interest otherwise provided under this Agreement.
This will not constitute a waiver of any event of default.

6.   CONDITIONS

The Bank must receive the following items, in form and content acceptable to the
Bank, before it is required to extend any credit to the Borrowers under this
Agreement:

6.1  Authorizations.  Evidence that the execution, delivery and performance by
each borrower of this Agreement and any instrument or agreement required under
this Agreement have been duly authorized.

7.   REPRESENTATIONS AND WARRANTIES

When the Borrowers sign this Agreement, and until the Bank is

                                 EXHIBIT 4 (a)

 
repaid in full, each Borrower makes the following representations and
warranties.  Each request for an extension of credit constitutes a renewed
representation:

7.1  Organization of Borrowers.  Each Borrower is a corporation duly formed and
existing under the laws of the state where organized.

7.2  Authorization.  This Agreement, and any instrument or agreement required
hereunder, are within each Borrower's powers, have been duly authorized, and do
not conflict with any of its organizational papers.

7.3  Enforceable Agreement.  This Agreement is a legal, valid and binding
agreement of each Borrower, enforceable against each Borrower in accordance with
its terms, and any instrument or agreement required hereunder, when executed and
delivered, will be similarly legal, valid, binding and enforceable.

7.4  Good Standing.  In each state in which each Borrower does business, it is
properly licensed, in good standing, and, where required, in compliance with
fictitious name statutes.

7.5  No Conflicts.  This Agreement does not conflict with any law, agreement, or
obligation by which any Borrower is bound.

7.6  Financial Information.  All financial and other information that has been
or will be supplied to the Bank is:

(a)  sufficiently complete to give the Bank accurate knowledge of the Borrowers'
     financial condition.

(b)  in the Borrowers' standard format for such information.

(c)  in compliance with all government regulations that apply.

7.7  Lawsuits.  There is no lawsuit, tax claim or other dispute pending or
threatened against any Borrower, which, if lost, would impair the Borrowers' or
any Borrower's financial condition or that of any Borrower's business, or would
impair any Borrower's ability to repay the loan, except as have been disclosed
in writing to the Bank.

7.8  Permits, Franchises.  Each Borrower possesses all permits, memberships,
franchises, contracts and licenses required and all trademark rights, trade name
rights, patent rights and fictitious name rights which such Borrower considers
to be necessary to enable it to conduct the business in which it is now engaged.

7.9  Other Obligations.  No Borrower is in default on any material obligation
for borrowed money, any purchase money obligation or any other material lease,
commitment, contract, instrument or

                                 EXHIBIT 4 (a)

 
obligation.

7.10 Income Tax Returns.  No Borrower has any knowledge of any pending material
assessments or adjustments of its income tax for any year.

7.11 No Event of Default.  There is no event which is, or with notice or lapse
of time or both would be, a default under this Agreement.

7.12 Location of Borrowers.  Each Borrower's place of business (or, if any
Borrower has more than one place of business, its chief executive office) is
located at the address listed under the Borrowers' signature on this Agreement.

8.   COVENANTS

The Borrowers agree, so long as credit is available under this Agreement and
until the Bank is repaid in full:

8.1  Use of Proceeds.  To use the proceeds of Facility No. 1 only for working
capital, for the financing of fixed, capital and acquired assets, for
acquisitions as permitted under paragraph 8.15(e) below, and for the issuance of
standby letters of credit.

8.2  Financial Information.  To provide the following financial information and
statements and such additional information as requested by the Bank from time to
time:

(a)  Within 100 days of the Borrowers' fiscal year end, the Borrowers' annual
     financial statements with consolidating schedules.  The consolidating
     schedules may be prepared by each Borrower.  These financial statements
     must be audited (with an unqualified opinion) by a Certified Public
     Accountant ("CPA") reasonably acceptable to the Bank.  Any of the so-called
     "Big Six" accounting firms are acceptable.  The statements shall be
     prepared on a consolidated basis.

(b)  Copies of the Borrowers' Form 10-K Annual Report within 100 days of the
     Borrowers' fiscal year end.

(c)  Copies of the Borrowers' Form 10-Q Quarterly Report within 50 days of the
     period's end.

8.3  Total Liabilities to Tangible Net Worth.  To maintain on a consolidated
basis a ratio of total liabilities excluding minority interest, to tangible net
worth not exceeding 1.00:1.00.

"Total liabilities" means the sum of current liabilities plus long term
liabilities.

"Tangible net worth" means the gross book value of the Borrowers'

                                 EXHIBIT 4 (a)

 
assets (excluding goodwill, patents, trademarks, trade names, organization
expense, treasury stock, unamortized debt discount and expense, deferred
research and development costs, deferred marketing expenses, and other like
intangibles, and monies due from affiliates, officers, directors or shareholders
of the Borrowers) less total liabilities, including but not limited to accrued
and deferred income taxes, and any reserves against assets.

8.4  Fixed Charge Coverage Ratio.  To maintain on a consolidated basis a Fixed
Charge Coverage Ratio of at least the amounts indicated for each period
specified below:

 
 
          Period                                        Ratio
          ------                                        -----
                                                      
          From the first fiscal quarter of 1996
          through the first fiscal quarter of 1998      1.1:1.0

          From the second fiscal quarter of 1998
          through the fourth fiscal quarter of 1998     1.0:1.0
 

"Fixed Charge Coverage Ratio" means the ratio of cash flow to fixed charges.
"Cash flow" means the sum of net income before taxes and minority interests,
plus interest expense, less cash dividends paid (excluding the first seven
Million Dollars ($7,000,000) in cash dividends paid in the aggregate during the
1995 and 1996 fiscal years).  "Fixed charges" means the sum of interest expense
(including capitalized interest), income taxes paid and the current portion of
long term debt (excluding the principal amount outstanding under Facility No. 1)
and capital leases.  During fiscal year 1996, this ratio will be calculated at
the end of each fiscal quarter, using fiscal year-to-date results on an
annualized basis.  Beginning with the first quarter of fiscal year 1997, this
ratio will be calculated at the end of each fiscal quarter, using the results of
that quarter and each of the 3 immediately preceding quarters.  The current
portion of long term debt will be measured as of the last day of the preceding
fiscal year.  From the second quarter through the fourth quarter of fiscal year
1998, the current portion of long term debt will include a portion of the
Facility No. 1 Commitment in the amount of Eleven Million Four Hundred Twenty
Eight Thousand Dollars ($11,428,000).

8.5  Other Debts.  Not to have outstanding or incur any direct or contingent
debts (other than those to the Bank), or become liable for the debts of others
without the Bank's written consent.  This does not prohibit:

(a)  Acquiring goods, supplies, or merchandise on normal trade credit.

(b)  Endorsing negotiable instruments received in the usual course of business.

(c)  Obtaining surety bonds in the usual course of business.

                                 EXHIBIT 4 (a)

 
(d)  Debts, lines of credit and leases in existence on the date of this
     Agreement disclosed in writing to the Bank.

(e)  Additional debts and lease obligations for the acquisition of fixed or
     capital assets, to the extent permitted under Paragraph 8.6(d) below.

(f)  The obligations of any Borrower under guarantees in favor or third parties
     to guarantee the performance of any Borrower's subsidiaries.

(g)  The obligations of any Borrower to the Zeneca Group.

(h)  Additional debts for the acquisition and renovation of real property after
     the date of this Agreement to the extent permitted under paragraph 8.6(f)
     below.

8.6  Other Liens.  Not to create, assume, or allow any security interest or lien
(including judicial liens) on property any Borrower now or later owns, except:

(a)  Deeds of trust and security agreements in favor of the Bank.

(b)  Liens for taxes not yet due.

(c)  Liens outstanding on the date of this Agreement disclosed in writing to the
     Bank.

(d)  Additional purchase money security interests in property acquired by the
     Borrowers or any one of them after the date of this Agreement if the total
     principal amount of debts secured by such liens does not exceed Ten Million
     Dollars ($10,000,000) in any fiscal year.

(e)  Liens pledging cash and marketable securities in support of performance
     bonds required under construction contracts of the Borrowers or any one of
     them in a total principal amount not exceeding Five Million Dollars
     ($5,000,000).

(f)  Liens on real property security debts arising from the acquisition and
     renovation of that real property if the total principal amount of debts
     secured by such liens does not exceed Fifteen Million Dollars ($15,000,000)
     outstanding at any one time.

8.7  Notices to Bank.  To promptly notify the Bank in writing of:

(a)  any lawsuit against any one or more of the Borrowers in an aggregate amount
     of One Million Dollars ($1,000,000) or more in excess of any insurance
     coverage.

(b)  any substantial dispute between any Borrower and any

                                 EXHIBIT 4 (a)

 
     government authority.

(c)  any failure to comply with this Agreement.

(d)  any material adverse change in any Borrower's financial condition or
     operations.

(e)  any change in any Borrower's name, legal structure, place of business, or
     chief executive office if such Borrower has more than one place of
     business;

8.8  Books and Records.  To maintain adequate books and records.

8.9  Audits.  To allow the Bank and its agents to inspect the Borrowers'
properties and examine, audit and make copies of books and records at any
reasonable time provided, however, that the Bank shall not engage in such
inspections and audits unless a default under Article 9 hereof has occurred.  If
any of the Borrowers' properties, books or records are in the possession of a
third party, the Borrowers authorize that third party to permit the Bank or its
agents to have access to perform inspections or audits and to respond to the
Bank's requests for information concerning such properties, books and records.

8.10 Compliance with Laws.  To comply with the laws (including any fictitious
name statute), regulations, and orders of any government body with authority
over each Borrower's business.

8.11 Preservation of Rights.  To maintain and preserve all rights, privileges,
and franchises each Borrower now has.

8.12 Maintenance of Properties.  To make any material repairs, renewals, or
replacements to keep each Borrower's properties in good working condition.

8.13 Cooperation.  To take any action reasonably requested by the Bank to carry
out the intent of this Agreement.

8.14 General Business Insurance.  To maintain insurance as is usual for the
business each Borrower is in.

8.15 Additional Negative Covenants.  Not to, without the Bank's written consent,
which will not be unreasonably withheld:

(a)  engage in any business activities substantially different from Borrowers'
     or any Borrower's present business or that of Zeneca or its affiliates.

(b)  liquidate or dissolve Borrowers' of any Borrower's business.

(c)  enter into any consolidation, merger, pool, syndicate, or other combination
     unless it is between a wholly owned

                                 EXHIBIT 4 (a)

 
     subsidiary of any Borrower.

(d)  enter into any joint venture unless it is related to the health care field.

(e)  lease, or dispose of all or a substantial part of Borrowers' or any
     Borrower's business or the Borrowers' or any Borrower's assets.

(f)  acquire or purchase a business or its assets, other than for the
     acquisition of companies in the Borrowers' lines of business, provided that
     the terms and conditions of such acquisitions are mutually agreeable
     between the seller and the Borrowers.

(g)  sell or otherwise dispose of any assets for less than fair market value, or
     enter into any sale and leaseback agreement covering any of the Borrowers'
     or any Borrower's fixed or capital assets.  Bank's prior written consent is
     not to be unreasonably withheld.

(h)  voluntarily suspend the Borrowers' or any Borrower's business for more than
     7 days in any 30 day period.

9.   DEFAULT

If any of the following events occur, the Bank may do one or more of the
following:  declare the Borrowers in default, stop making any additional credit
available to the Borrowers, and require the Borrowers to repay their entire debt
immediately and without prior notice; provided, further, the Bank may stop
making any additional credit available to any Borrower during any cure period
specified below.  Except as provided in Paragraph 9.3, if a bankruptcy petition
is filed with respect to any Borrower, then the entire debt outstanding under
this Agreement will automatically become due immediately.

9.1  Failure to Pay.  Any Borrower fails to make a payment under this Agreement
within 15 days after the date when due.

9.2  False Information.  Any Borrower has given the Bank false or misleading
information or representations.

9.3  Bankruptcy.  Any Borrower files a bankruptcy petition, a bankruptcy
petition is filed against any Borrower, or any Borrower makes a general
assignment for the benefit of creditors.  The default will be deemed cured if
any bankruptcy petition filed against any Borrower is dismissed within a period
of thirty (30) days after the filing.

9.4  Receivers.  A receiver or similar official is appointed for any Borrower's
business, or the business is terminated.  The

                                 EXHIBIT 4 (a)

 
default will be deemed cured if any receiver or similar official, other than one
appointed at the Borrowers' request or, is dismissed within a period of thirty
(30) days after the appointment.

9.5  Judgments.  Any judgments or arbitration awards are entered against any one
or more of Borrowers, or any one or more of Borrowers enters into any settlement
agreements with respect to any litigation or arbitration, in an aggregate amount
of Three Million Dollars ($3,000,000) or more in excess of any insurance
coverage, provided that said judgments, arbitration awards or settlement
agreements are not vacated or discharged within thirty (30) days.

9.6  Government Action.  Any government authority takes action that the Bank
believes materially adversely affects any Borrower's financial condition or
ability to repay and such action continues for thirty (30) days.

9.7  Material Adverse Change.  A material adverse change occurs in any
Borrower's financial condition, properties, or ability to repay the loan.

9.8  Cross-default.  Any default occurs under any agreement in connection with
any credit any Borrower has obtained from anyone else or which any Borrower has
guaranteed in the amount of Two Million Dollars ($2,000,000) or more in the
aggregate if the default consists of failing to make a payment when due or gives
the other lender the right to accelerate the obligation.  If, in the Bank's
opinion, the breach is capable of being remedied, the breach will not be
considered an event of default under this Agreement for a period of 30 days
after the date on which the Bank gives written notice of the breach to such
Borrower; provided, however, that the Bank will not be obligated to extend any
additional credit to the Borrowers during that period.

9.9  Other Bank Agreements.  Any Borrower fails to meet the conditions of, or
fails to perform any obligation under any other agreement in the amount to Two
Million Dollars ($2,000,000) or more in the aggregate that any Borrower has with
the Bank or any affiliate of the Bank which has not been cured within any
applicable cure period.

9.10 Other Breach Under Agreement.  Any Borrower fails to meet the conditions
of, or fails to perform any obligation under, any term of this Agreement not
specifically referred to in this Article.

10.  ENFORCING THIS AGREEMENT; MISCELLANEOUS

10.1 GAAP.  Except as otherwise stated in this Agreement, all financial
information provided to the Bank and all financial covenants will be made under
generally accepted accounting principles, consistently applied.

                                 EXHIBIT 4 (a)

 
10.2 California Law.  This Agreement is governed by California law.

10.3 Successors and Assigns.  This Agreement is binding on the Borrowers' and
the Bank's successors and assignees.  The Borrowers agree that they may not
assign this Agreement without the Bank's prior consent.

10.4 Arbitration.

(a)  This paragraph concerns the resolution of any controversies or claims
     between any one or more of Borrowers and the Bank, including but not
     limited to those that arise from:

     (i)  This Agreement (including any renewals, extensions or modifications of
          this Agreement);

     (ii) Any document, agreement or procedure related to or delivered in
          connection with this Agreement;

    (iii) Any violation of this Agreement; or

     (iv) Any claims for damages resulting from any business conducted between
          any one or more of Borrowers and the Bank, including claims for injury
          to persons, property or business interests (torts).

(b)  At the request of any Borrower or the Bank, any such controversies or
     claims will be settled by arbitration in accordance with the United States
     Arbitration Act.  The United States Arbitration Act will apply even though
     this Agreement provides that it is governed by California law.

(c)  Arbitration proceedings will be administered by the American Arbitration
     Association and will be subject to its commercial rules of arbitration.

(d)  For purposes of the application of the statute of limitations, the filing
     of an arbitration pursuant to this paragraph is the equivalent of the
     filing of a lawsuit, and any claim or controversy which may be arbitrated
     under this paragraph is subject to any applicable statute of limitations.
     The arbitrators will have the authority to decide whether any such claim or
     controversy is barred by the statute of limitations and, if so, to dismiss
     the arbitration on that basis.

(e)  If there is a dispute as to whether an issue is arbitrable, the arbitrators
     will have the authority to resolve any such dispute.

(f)  The decision that results from an arbitration proceeding may be submitted
     to any authorized court of law to be confirmed and enforced.

                                 EXHIBIT 4 (a)

 
(g)  The procedure described above will not apply if the controversy or claim,
     at the time of the proposed submission to arbitration, arises from or
     relates to an obligation to the Bank secured by real property located in
     California. In this case, both the Borrowers and the Bank must consent to
     submission of the claim or controversy to arbitration. If both parties do
     not consent to arbitration, the controversy or claim will be settled as
     follows:

     (i)  The Borrowers and the Bank will designate a referee (or a panel of
          referees) selected under the auspices of the American Arbitration
          Association in the same manner as arbitrators are selected in
          Association-sponsored proceedings;

     (ii) The designated referee (or the panel of referees) will be appointed by
          a court as provided in California Code of Civil Procedure Section 638
          and the following related sections;

    (iii) The referee (or the presiding referee of the panel) will be an active
          attorney or a retired judge; and

     (iv) The award that results from the decision of the referee (or the panel)
          will be entered as a judgment in the court that appointed the referee,
          in accordance with the provisions of California Code of Civil
          Procedure Sections 644 and 645.

(h)  This provision does not limit the right of the Borrowers or the Bank to:

     (i)  exercise self-help remedies such as setoff;

     (ii) foreclose against or sell any real or personal property collateral; or

    (iii) act in a court of law, before, during or after the arbitration
          proceeding to obtain:

          (A)  an interim remedy; and/or

          (B) additional or supplementary remedies.

(i)  The pursuit of or a successful action for interim, additional or
     supplementary remedies, or the filing of a court action, does not
     constitute a waiver of the right of the Borrowers or the Bank, including
     the suing party, to submit the controversy or claim to arbitration if the
     other party contests the lawsuit.  However, if the controversy or claim
     arises from or relates to an obligation to the Bank which is secured by
     real property located in California at the time of the proposed

                                 EXHIBIT 4 (a)

 
     submission to arbitration, this right is limited according to the provision
     above requiring the consent of both the Borrowers and the Bank to seek
     resolution through arbitration.

(j)  If the Bank forecloses against any real property securing this Agreement,
     the Bank has the option to exercise the power of sale under the deed of
     trust or mortgage, or to proceed by judicial foreclosure.

10.5 Severability; Waivers.  If any part of this Agreement is not enforceable,
the rest of the Agreement may be enforced.  The Bank retains all rights, even it
if makes a loan after default.  If the Bank waives a default, it may enforce a
later default.  Any consent or waiver under this Agreement must be in writing.

10.6 Attorneys' Fees.  The Borrowers shall reimburse the Bank for any reasonable
costs and attorneys' fees incurred by the Bank in connection with the
enforcement or preservation of any rights or remedies under this Agreement and
any other documents executed in connection with this Agreement, and including
any amendment, waiver, "workout" or restructuring under this Agreement.  In the
event of a lawsuit or arbitration proceeding, the prevailing party is entitled
to recover costs and reasonable attorneys' fees incurred in connection with the
lawsuit or arbitration proceeding, as determined by the court or arbitrator.  As
used in this paragraph, "attorneys' fees" includes the allocated costs of in-
house counsel.

10.7 Joint and Several Liability.

(a)  Each Borrower agrees that it is jointly and severally liable to the Bank
     for the payment of all obligations arising under this Agreement, and that
     such liability is independent of the obligations of the other Borrower(s).
     The Bank may bring an action against any Borrower, whether an action is
     brought against the other Borrower(s).

(b)  Each Borrower agrees that any release which may be given by the Bank to the
     other Borrower(s) will not release such Borrower from its obligations under
     this Agreement.

(c)  Each Borrower waives any right to assert against the Bank any defense,
     setoff, counterclaim, or claims which such Borrower may have against the
     other Borrower(s) or any other party liable to the Bank for the obligations
     of the Borrowers under this Agreement.

(d)  Each Borrower agrees that it is solely responsible for keeping itself
     informed as to the financial condition of the other Borrower(s) and of all
     circumstances which bear upon the risk of nonpayment.  Each Borrower waives
     any right it may have to require the Bank to disclose to such Borrower any
     information

                                 EXHIBIT 4 (a)

 
     which the Bank may now or hereafter acquire concerning the financial
     condition of the other Borrower(s).

(e)  Each Borrower waives all rights to notices of default or nonperformance by
     any other Borrower under this Agreement.  Each Borrower further waives all
     rights to notices of the existence or the creation of new indebtedness by
     any other Borrower.

(f)  The Borrowers represent and warrant to the Bank that each will derive
     benefit, directly and indirectly, from the collective administration and
     availability of credit under this Agreement.  The Borrowers agree that the
     Bank will not be required to inquire as to the disposition by any Borrower
     of funds disbursed in accordance with the terms of this Agreement.

(g)  Each Borrower waives any right of subrogation, reimbursement,
     indemnification and contribution (contractual, statutory or otherwise),
     including without limitation, any claim or right of subrogation under the
     Bankruptcy Code (Title 11 of the U.S. Code) or any successor statute, which
     such Borrower may now or hereafter have against any other Borrower with
     respect to the indebtedness incurred under this Agreement.  Each Borrower
     waives any right to enforce any remedy which the Bank now has or may
     hereafter have against any other Borrower, and waives any benefit of, and
     any right to participate in, any security now or hereafter held by the
     Bank.

10.8 One Agreement.  This Agreement and any related security or other agreements
required by this Agreement, collectively:

(a)  represent the sum of the understandings and agreements between the Bank and
     the Borrowers concerning this credit; and

(b)  replace any prior oral or written agreements between the Bank and the
     Borrowers concerning this credit; and

(c)  are intended by the Bank and the Borrowers as the final, complete and
     exclusive statement of the terms agreed to by them.

In the event of any conflict between this Agreement and any other agreements
required by this Agreement, this Agreement will prevail.

10.9 Notices.  All notices required under this Agreement shall be personally
delivered or sent by first class mail, postage prepaid, to the addresses on the
signature page of this Agreement, or to such other addresses as the Bank and the
Borrowers may specify from time to time in writing.

10.10 Headings.  Article and paragraph headings are for reference

                                 EXHIBIT 4 (a)

 
only and shall not affect the interpretation or meaning of any provisions of
this Agreement.

10.11 Counterparts.  This Agreement may be executed in as many counterparts as
necessary or convenient, and by the different parties on separate counterparts
each of which, when so executed, shall be deemed an original but all such
counterparts shall constitute but one and the same agreement.

10.12 Prior Agreement Superseded.  This Agreement supersedes the Business Loan
Agreement entered into as of January 1, 1993, between the Bank and the
Borrowers, and any credit outstanding thereunder shall be deemed to be
outstanding under this Agreement.

                                 EXHIBIT 4 (a)

 
This Agreement is executed as of the date stated at the top of the first page.


BANK OF AMERICA
NATIONAL TRUST AND SAVINGS
ASSOCIATION                              SALICK HEALTH CARE, INC.              
                                                                               
                                                                               
                                                                               
/S/ SCOTT ANEY                           /S/ BERNARD SALICK, M.D.              
- ----------------------------             -------------------------------       
By:    Scott Aney                        By:    Bernard Salick, M.D.           
Title: Vice President                    Title: Chairman of the Board of       
                                                Directors, Chief               
                                                Executive Officer and          
                                                President                      
                                                                               
                                                                               
                                                                               
                                         /S/ LESLIE F. BELL                    
                                         -------------------------------       
                                         By:    Leslie F. Bell                 
                                         Title: Executive Vice President,      
                                                Chief Financial Officer,       
                                                Secretary and Director         
                                                                               
                                                                               
                                         USHAWL, Inc.                          
                                                                               
                                                                               
                                                                               
                                                                               
                                         /S/ BERNARD SALICK, M.D.              
                                         -------------------------------       
                                         By:    Bernard Salick, M.D.           
                                         Title: Chairman of the Board of       
                                                Directors, Chief               
                                                Executive Officer and          
                                                President                      
                                                                               
                                                                               
                                                                               
                                         /S/ LESLIE F. BELL                    
                                         -------------------------------       
                                         By:    Leslie F. Bell                 
                                         Title: Executive Vice President,      
                                                Chief Financial Officer,       
                                                Secretary and Director          


                                 EXHIBIT 4 (a)

 
                                         Century Dialysis Corporation          
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                         /S/ BERNARD SALICK, M.D.              
                                         -------------------------------       
                                         By:    Bernard Salick, M.D.           
                                         Title: Chairman of the Board of       
                                                Directors, Chief               
                                                Executive Officer and          
                                                President                      
                                                                               
                                                                               
                                                                               
                                         /S/ LESLIE F. BELL                    
                                         -------------------------------       
                                         By:    Leslie F. Bell                 
                                         Title: Executive Vice President,      
                                                Chief Financial Officer,       
                                                Secretary and Director         
                                                                               
                                                                               
                                         Comprehensive Cancer Centers, Inc.,   
                                         a California Corporation              
                                                                               
                                                                               
                                                                               
                                                                               
                                         /S/ BERNARD SALICK, M.D.              
                                         -------------------------------       
                                         By:    Bernard Salick, M.D.           
                                         Title: Chairman of the Board of       
                                                Directors, Chief               
                                                Executive Officer and          
                                                President                      
                                                                               
                                                                               
                                                                               
                                         /S/ LESLIE F. BELL                    
                                         -------------------------------       
                                         By:    Leslie F. Bell                 
                                         Title: Executive Vice President,      
                                                Chief Financial Officer,       
                                                Secretary and Director          

                                 EXHIBIT 4 (a)

 
                                         Ambulatory Diagnostic Services, Inc.
                                                                             
                                                                             
                                                                             
                                         /S/ BERNARD SALICK, M.D.            
                                         -------------------------------     
                                         By:    Bernard Salick, M.D.         
                                         Title: Chairman of the Board of     
                                                Directors, Chief             
                                                Executive Officer and        
                                                President                    
                                                                             
                                                                             
                                                                             
                                         /S/ LESLIE F. BELL                  
                                         -------------------------------     
                                         By:    Leslie F. Bell               
                                         Title: Executive Vice President,    
                                                Chief Financial Officer,     
                                                Secretary and Director       
                                                                             
                                                                             
                                                                             
                                         Aurora Medical Supplies, Inc.,      
                                         a California Corporation            
                                                                             
                                                                             
                                                                             
                                         /S/ BERNARD SALICK, M.D.            
                                         -------------------------------     
                                         By:    Bernard Salick, M.D.         
                                         Title: Chairman of the Board of     
                                                Directors, Chief             
                                                Executive Officer and        
                                                President                    
                                                                             
                                                                             
                                                                             
                                         /S/ LESLIE F. BELL                  
                                         -------------------------------     
                                         By:    Leslie F. Bell               
                                         Title: Executive Vice President,    
                                                Chief Financial Officer,     
                                                Secretary and Director       

                                 EXHIBIT 4 (a)

 
                                         Comprehensive Cancer Center, Inc.-  
                                         Philadelphia                       
                                                                            
                                                                            
                                                                            
                                         /S/ BERNARD SALICK, M.D.           
                                         -------------------------------    
                                         By:    Bernard Salick, M.D.        
                                         Title: Chairman of the Board of    
                                                Directors, Chief            
                                                Executive Officer and       
                                                President                   
                                                                            
                                                                            
                                                                            
                                         /S/ LESLIE F. BELL                 
                                         -------------------------------    
                                         By:    Leslie F. Bell              
                                         Title: Executive Vice President,   
                                                Chief Financial Officer,    
                                                Secretary and Director      
                                                                            
                                                                            
                                         Comprehensive Cancer Center, Inc.- 
                                         Kansas City                        
                                                                            
                                                                            
                                                                            
                                         /S/ BERNARD SALICK, M.D.           
                                         -------------------------------    
                                         By:    Bernard Salick, M.D.        
                                         Title: Chairman of the Board of    
                                                Directors, Chief            
                                                Executive Officer and       
                                                President                   
                                                                            
                                                                            
                                                                            
                                         /S/ LESLIE F. BELL                 
                                         -------------------------------    
                                         By:    Leslie F. Bell              
                                         Title: Executive Vice President,   
                                                Chief Financial Officer,    
                                                Secretary and Director       

                                 EXHIBIT 4 (a)

 
                                         SHC Laboratories, Inc.             
                                                                            
                                                                            
                                                                            
                                                                            
                                         /S/ BERNARD SALICK, M.D.           
                                         -------------------------------    
                                         By:    Bernard Salick, M.D.        
                                         Title: Chairman of the Board of    
                                                Directors, Chief            
                                                Executive Officer and       
                                                President                   
                                                                            
                                                                            
                                                                            
                                         /S/ LESLIE F. BELL                 
                                         -------------------------------    
                                         By:    Leslie F. Bell              
                                         Title: Executive Vice President,   
                                                Chief Financial Officer,    
                                                Secretary and Director      
                                                                            
                                                                            
                                         Comprehensive Cancer Centers-      
                                         West Valley, Inc.                  
                                                                            
                                                                            
                                                                            
                                         /S/ BERNARD SALICK, M.D.           
                                         -------------------------------    
                                         By:    Bernard Salick, M.D.        
                                         Title: Chairman of the Board of    
                                                Directors, Chief            
                                                Executive Officer and       
                                                President                   
                                                                            
                                                                            
                                                                            
                                         /S/ LESLIE F. BELL                 
                                         -------------------------------    
                                         By:    Leslie F. Bell              
                                         Title: Executive Vice President,   
                                                Chief Financial Officer,    
                                                Secretary and Director       

Address where notices to the             Address where notices to the
Bank are to be sent:                     Borrowers are to be sent:   
                                                                     
Century City Regional                    Salick Health Care, Inc.    
Commercial Banking                       8201 Beverly Blvd.          
Office #1417                             Los Angeles, CA  90048       
2049 Century Park East
Los Angeles, CA  90067

                                 EXHIBIT 4(a)