STATE OF MICHIGAN
                         MICHIGAN DEPARTMENT OF TREASURY
                              CORPORATION DIVISION
                                LANSING, MICHIGAN



                DO NOT WRITE IN SPACE BELOW -- FOR DEPARTMENT USE

   Date Received:     Compared by:

    JAN 27 1969 
                
                                                This is to certify this
                     Date:                      document to be a true copy
                                                of the original on file in this
                                                office.
                                                            FILED
                                                         JAN 29 1969
                     Examiner:                  /s/ Allison Grun
                                                         STATE TREASURER
                                                Michigan Department of
                                                Treasury






                            ARTICLES OF INCORPORATION

These Articles of Incorporation are signed and acknowledged by the incorporators
for the purpose of forming a corporation  for profit under the provisions of Act
No. 327 of the Public Acts of 1931, as amended, as follows:

                                   ARTICLE I.

The name of the corporation is ADVANCE MEDICAL & RESEARCH CENTER, INC.

                                   ARTICLE II.

The purpose or purposes for which the corporation is formed are as follows:

To conduct, operate, own, manage and generally carry on the business of medical,
clinical and research laboratories within the State of Michigan, and to acquire,
lease,  own and convey  and  dispose of real or  personal  property  used in the
operation of said business.







In general to carry on any business in connection therewith and incident thereto
not  forbidden  by the laws of the  State of  Michigan  and with all the  powers
conferred upon corporations by the laws of the State of Michigan.

                                  ARTICLE III.

Location of the first registered office is:

        1509 S. Telegraph     Pontiac      Oakland       Michigan   48053


Post office address of the first registered office is:

        1509 S. Telegraph     Pontiac                    Michigan   48053



                                   ARTICLE IV.

The name of the first resident agent is   Robert L. Moloney



                                        1





                                   ARTICLE V.

                      The total authorized capital stock is

                  Preferred shs. NONE    Par Value $    NONE

(1)                                                              per share

                  Common shs.    50,000  Par Value $    1.00


                                             Book Value $
                                                                 per share

                  Preferred      none        Price fixed for sale 

and/or shs. of (2)                  no par value
                  Common                     Book Value $
                                                                 per share

                                             Price fixed for sale $

     (3) A statement of all or any of the designations and the powers,
preferences and rights, and the qualifications, limitations or restrictions
thereof is as follows:

     All shares of stock shall have the same powers, preferences and rights.



                                   ARTICLE VI.

The names and places of residence or business of each of the  incorporators  and
the number and class of shares  subscribed for by each are as follows:  (Statute
requires one or more incorporators)



Name   Residence or Business Address                Number of Shares


                                         Par Stock            Non-Par Stock
 
                                         Common  Preferred  Common  Preferred

Robert L. Moloney

      1509 S. Telegraph Pontiac, Mich.   18,000



                                  ARTICLE VII.

The names and addresses of the first board of directors are as follows:
(Statute requires at least three directors)

       Name                      Residence or Business Address

Robert L. Moloney            1509 S. Telegraph, Pontiac, Michigan

Richard E. Arnold            1940 Welbeck, Union Lake, Michigan

Aldoph H. Magnus, Jr.        879 Foxhall Rd. Bloomfield Hills, Michigan


                                  ARTICLE VIII.

The term of the corporate existence is perpetual. 

(If term is for a limited number of years, then state the number of years
instead of perpetual)


                                        2



                                   ARTICLE IX.

OPTIONAL          (Please delete Article IX if not applicable)

Whenever a  compromise  or  arrangement  or any plan of  reorganization  of this
corporation is proposed  between this corporation and its creditors or any class
of them or between this  corporation and its  shareholders or any class of them,
any court of equity jurisdiction within the state may on the application of this
corporation or of any creditor or any shareholder thereof, or on the application
of any receiver or receivers appointed for this corporation,  order a meeting of
the  creditors  or  class  of  creditors,  or of the  shareholders  or  class of
shareholders,  to be affected  by the  proposed  compromise  or  arrangement  or
reorganization,  to be  summoned  in such  manner as said  court  directs.  If a
majority in number representing three-fourths in value of the creditors or class
of creditors, or of the shareholders or class of shareholders, to be affected by
the  proposed  compromise  or  arrangement  or  reorganization,   agree  to  any
compromise or  arrangement  or to any  reorganization  of this  corporation as a
consequence of such  compromise or  arrangement,  said compromise or arrangement
and said  reorganization  shall,  if  sanctioned  by the court to which the said
application  has  been  made,  be  binding  on all the  creditors  or  class  of
creditors, or on all the shareholders or class of shareholders, and also on this
corporation.

                                   ARTICLE X.

      (Here insert any desired additional provisions authorized by the Act)


          This corporation is organized with plan to qualify under Sec.
          1244, Sub-Chapter P - Capital Gains & Losses, and under Secs. 1372,
          1373 and 1374, Sub-Chapter S - Election of Certain Small Business
          Corporations as to Taxable Status, of amendments to Internal Revenue
          Code of 1954.


We, the incorporators, sign our names this  23rd day of January   19   69.

   (All parties appearing under Article VI are required to sign in this space)


        /s/ Robert L. Moloney
        ---------------------
         Robert L. Moloney







STATE OF MICHIGAN }       (One or more of the parties signing must acknowledge
                  }    ss.                before the Notary)
COUNTY OF OAKLAND }

On this  23rd day of January  1969,
before me personally appeared Robert L. Moloney


to me  known to be the  persons  described  in and who  executed  the  foregoing
instrument,  and acknowledged  that they executed the same as their free act and
deed.


                              (Signature of Notary)
         
                              /s/ Sheila Steinhoff
           ----------------------------------------------------------------
                          (Print or type name  of Notary)
         
           Notary Public for  Oakland County,
           State of Michigan.
         
           My commisison expires    3/8/70
            (Notarial seal required if acknowledgment taken out of State)
         
       

                                        3





                                STATE OF MICHIGAN
                         MICHIGAN DEPARTMENT OF TREASURY
                              CORPORATION DIVISION
                                LANSING, MICHIGAN


                 NOTE                      DO NOT WRITE IN SPACE BELOW -- 
                                           FOR DEPARTMENT USE

Mail ONE signed and acknowledged copy to   Date Received:

   Michigan Department of Treasury          DEC-9 1969
        Corporation Division
            P.O. Drawer C
      Lansing, Michigan  48904
          Filing Fee $5.00
        (Make fee payable to
         State of Michigan)


This is to certify this document to be a
true copy of the original on file in this
office.
             FILED
             DEC 11 1969
/s/ Allison Grun
                      STATE TREASURER
MICHIGAN DEPARTMENT OF TREASURY



                         CERTIFICATE OF AMENDMENT TO THE
                            ARTICLES OF INCORPORATION

                     Advance Medical & Research Center, Inc.

a Michigan corporation, whose registered office is located at
1509 South Telegraph
 Pontiac  Oakland  Michigan 48053 certifies pursuant to the

provisions  of Section 43 of Act No. 327 of the Public Acts of 1931, as amended,
that at a meeting of the Shareholders

of  said  corporation  called  for the  purpose  of  amending  the  articles  of
incorporation,  and held on the 7th day of November  1969 it was resolved by the
unanimous  vote of each class  entitled to vote and of each class whose  rights,
privileges or preferences are changed,


that  Article  No. V of the  Articles  of  Incorporation  is  amended to read as
follows, viz.:

                                   ARTICLE V.
    (Any article being amended is required to be set forth in its entirety.)

The total authorized capital stock is:
     (1)   50,000 Shares of $1.00 par value common stock
     (2) 500 Shares of $100.00 par value Class A 7% Cumulative  Preferred Shares
     (3) A  statement  of  all  or  any of  the  designations  and  the  powers,
     preferences and rights, and
the qualifications, limitations or restrictions thereof is as follows:
     The Common  stock is fully  paid,  non-assessable,  voting  stock,  without
     pre-emptive  rights.  
     The Class A 7% Cumulative Preferred stock shall be entitled to a cumulative
dividend  of $7.00 per share  accruing as of November 1, of each year as to each
share issued and outstanding on that date and subject to payment form the earned
surplus of the  corporation at such times as declared by the Board of Directors;
it shall be entitled and limited to  preferential  payment on  liquidation of an
amount equal to its par value prior to any liquidation  payments upon the issued
and  outstanding  common stock;  it shall be non-voting;  it shall be subject to
call by the corporation at any time prior to November 1, 1979, and to redemption
at the shareholders option


                                        4



on or after November 1, 1979, at a call or redemption price of $110.00 per share
plus any accrued and unpaid  dividends;  it shall be convertible on a dollar for
dollar  basis into any future  common  stock  issue  which may be offered to the
public while such preferred stock is outstanding,  provided that such conversion
rights shall  terminate  thirty days after written notice to the  stockholder of
the availability of the public issue for conversion.


NOTE:  Sec. 43. amended by Act 155, P.A. 1953, provides:

     ". . . That any amendment which impairs the preemptive right of the
     holders of shares of any class of capital stock entitled to such right
     shall be approved by the vote of the holders of 2/3 of the shares of each
     such class . . . . "

Signed on December 6, 1969.

Affix Corporate Seal Here
                                   ADVANCE MEDICAL & RESEARCH CENTER, INC.
                                             (Corporate Name)
                   
                                   By /s/ Robert L. Moloney
                                      ----------------------------------
                                      (President or Vice-President)
                                      Robert L. Moloney

                                      /s/ James L. Howlet
                                      ----------------------------------
                                      (Secretary or Assistant Secretary)
                                       James L. Howlett


STATE OF MICHIGAN

COUNTY OF OAKLAND } SS

     On this 6 day of December, 1969, before me appeared


           Robert L. Moloney

to me personally known, who, being by me duly sworn, did say that he is the 
president or

of Advance Medical & Research Center, Inc.,

which  executed the  foregoing  instrument,  and that* [the seal affixed to said
instrument is the corporate seal of said corporation,  and that] said instrument
was signed* [and sealed] in behalf of said corporation by authority of its board
of directors,  and said officer  acknowledged said instrument to be the free act
and deed of said corporation.


*If corporation has no seal strike out the words
in brackets and add at end of acknowledgment
the following:  "and that said corporation has
no corporate seal".

              /s/ Norma M. Anderson 
              --------------------- 
               Norma M. Anderson

   Notary Public for Oakland County  
   State of Michigan

   My Commisison expires May 13, 1972  
      (Notarial seal required if       
       acknowledgment taken out        
             of State)                 

                                        5





                       (For Use By Domestic Corporations)

                         CERTIFICATE OF AMENDMENT TO THE

                          ARTICLES OF INCORPORAITON OF


                     ADVANCE MEDICAL & RESEARCH CENTER, INC.
                              (Name of Corporation)


         The undersigned corporation executes the following Certificate
            of Amendment to its Articles of Incorporation pursuant to
             the provisions of Section 631, Act 284, Public Acts of
                                      1972:




1.   The name of the corporation is Advance Medical & Research Center, Inc.


The location of the registered office is

   1270 Doris Road Pontiac, Michigan 48057


2.   The following amendment to the Articles of Incorporation was adopted by the
     shareholders of the corporation in accordance with Subsection

(2) of Section 611, Act 284, Public Acts of 1972, on the 19th day of May, 1978:

     Resolved, that Article V of the Articles of Incorporation be amended to
read as follows: (Any article being amended is required to be set forth in its
entirety.)


The total authorized capital stock is:

          (1)  50,000 shares of $1.00 par value common stock.

3.   The necessary number of shares as required by statute were voted in favor
     of the amendment.

Dated this 31st day of May, 1978.



                                       ADVANCE MEDICAL & RESEARCH CENTER, INC.


                                       By /s/ Robert L. Moloney, President
                                          ------------------------------------
                                          Robert L. Moloney, President




                                        6





- --------------------------------------------------------------------------------
       MICHIGAN DEPARTMENT OF COMMERCE - CORPORATION AND SECURITIES BUREAU
- --------------------------------------------------------------------------------
Date Received                                        (FOR BUREAU USE ONLY)

DEC 15 1995                                                  FILED

                                                          DEC 15 1995

                                                         Administrator
                                                MICHIGAN DEPARTMENT OF COMMERCE
                                                Corporation & Securities Bureau
Name

Address

City
                                                EFFECTIVE DATE:
- --------------------------------------------------------------------------------
Document will be returned to the name and address you enter above


            CERTIFICATE OF AMENDMENT TO THE ARTICLES OF INCORPORATION
                     For use by Domestic Profit Corporations
           (Please read information and instructions on the last page)


     Pursuant to the provisions of Act 284, Public Acts of 1972 (profit
corporations), or Act 162, Public Acts of 1982 (nonprofit corporations), the
undersigned corporation executes the following Certificate:

- --------------------------------------------------------------------------------

1.   The present name of the corporation is:  ADVANCE MEDICAL & RESEARCH 
                                              CENTER, INC.

2.   The identification number assigned by the Bureau is:      179-214

3.   The location of the registered office is:  The Corporation Company

30600 Telegraph Road, Bingham Farms, Michigan              48025
- -----------------------------------          -----------------------------------
(Street Address)            (City)                       (Zip Code)

4.   Article I of the Articles of Incorporation is hereby amended to read as
     follows:

"The name of the corporation is Corning Clinical Laboratories Inc."

- --------------------------------------------------------------------------------


                                        7





5.   COMPLETE SECTION (a) IF THE AMENDMENT WAS ADOPTED BY THE UNANIMOUS
     CONSENT OF THE INCORPORATOR(S) BEFORE THE FIRST MEETING OF THE BOARD OF
     DIRECTORS OR TRUSTEES; OTHERWISE, COMPLETE SECTION (b).  DO NOT COMPLETE
     BOTH.

     a.    |_|    The foregoing amendment to the Articles of Incorporation was
                  adopted on the day of            , 19   , in accordance with
                  the provisions of the Act by the unanimous consent of the
                  incorporator(s) before the first meeting of the Board of
                  Directors of Trustees.

                           Signed this             day of  , 19   .


               --------------------                        --------------------
                   (Signature)                                  (Signature)

               --------------------                        --------------------
               (Type or Print Name)                        (Type or Print Name)

               --------------------                        --------------------
                  (Signature)                                  (Signature)

               --------------------                        --------------------
                (Type or Print Name)                       (Type or Print Name)

     b.    |_|    The foregoing amendment to the Articles of Incorporation was
                  duly adopted on the 25th day of November, 1995. The amendment:
                  (check one of the following)

                  |_|  was duly adopted in accordance with Section 611(2) of the
                       Act by the vote of the shareholders if a profit
                       corporation, or by the vote of the shareholders or
                       members if a nonprofit corporation, or by the vote of the
                       directors if a nonprofit corporation organized on a
                       nonstock directorship basis. The necessary votes were
                       cast in favor of the amendment.

                  |_|  was duly adopted by the written consent of all directors
                       pursuant to Section 525 of the Act and the corporation is
                       a nonprofit corporation organized on a nonstock
                       directorship basis.

                  |_|  was duly adopted by the written consent of the
                       shareholders or members having not less than the minimum
                       number of votes required by statute in accordance with
                       Section 407(1) and (2) of the Act if a nonprofit
                       corporation, or Section 407(1) of the Act if a profit
                       corporation. Written notice to shareholders who have not
                       consented in writing has been given. (Note: Written
                       consent by less than all of the shareholders or members
                       is permitted only if such provision appears in the
                       Articles of Incorporation.)

                  |X|  was duly adopted by the written consent of all the
                       shareholders or members entitled to vote in accordance
                       with Section 407(3) of the Act if a nonprofit
                       corporation, or Section 407(2) of the Act if a profit
                       corporation.

                          Signed this 28 day of December, 1995

                          By____________________________________________________
                               (Only Signature of President Vice-President,
                                     Chairperson, or Vice-Chairperson)

                                 Raymond C. Marier           Vice President
                            ----------------------------------------------------
                                (Type or Print Name)      (Type or Print Name)

                                        8





                              CERTIFICATE OF MERGER
                                       OF
                          METPATH SERVICES CORPORATION
                              AND METPATH TPA, INC.
                                      INTO
                       CORNING CLINICAL LABORATORIES INC.
                            (a Michigan corporation)

                                   ----------


To the Administrator
Michigan Department of Commerce
Corporation and Securities Bureau
Corporate Division
State of Michigan

     Pursuant to the provisions of the Business Corporation Act of the State of
Michigan, Act 284 P. A. 1972, it is hereby certified that:

     1. Annexed hereto and made a part hereof is the Plan of Merger for merging
MetPath Services Corporation ("MSC") and MetPath TPA, Inc. ("TPA"), each a
Michigan business corporation, with and into Corning Clinical Laboratories Inc.
("CCL"), a Michigan business corporation.

     2. The Plan of Merger has been adopted by the Board of Directors of MSC and
TPA in accordance with Section 701 of the Business Corporation Act and has been
approved by the shareholders of MSC and TPA entitled to vote thereon in
accordance with Section 703a of the Business Corporation Act, except that all of
the shareholders entitled to vote dispensed with the holding of the meeting of
shareholders otherwise prescribed by Section 703a of the Business Corporation
Act and approved the Plan of Merger by a consent in writing signed by all of
them without any such meeting.

        The Plan of Merger has been adopted by the Board of Directors of CCL in
accordance with Section 701 of the Business Corporation Act. No approval by the
shareholders of CCL was required under Section 703a of the Business Corporation
Act or by the Articles of Incorporation of CCL.

     3. The number of outstanding shares of MSC is 1,000, all of which are of
one class and are common shares. The number of outstanding shares of TPA is
1,000, all of which are of one class and are common shares. The number of
outstanding shares of CCL is 22,000, all of which are of one class and common
shares.

     4. The Plan of Merger does not amend the Articles of Incorporation of CCL.

     5. The Plan of Merger will be furnished by CCL, on request and without
cost, to any shareholder of CCL, TPA or MSC.

     6. The effective date is: August 31, 1996 at 11:59 p.m. Executed as of June
30, 1996.


                                        9





                                       CORNING CLINICAL LABORATORIES INC. (MI)



                                       By: /s/ Kenneth Roe
                                          -------------------------------------
                                             Kenneth Roe
                                             President


                                       METPATH SERVICES CORPORATION



                                       By:  /s/ Kenneth Roe
                                          -------------------------------------
                                             Kenneth Roe
                                             President


                                       METPATH TPA, INC.



                                       By:  /s/ Douglas VanOort
                                          -------------------------------------
                                             Douglas VanOort
                                             Vice President



                                       10





                                 PLAN OF MERGER
                                       OF
                          METPATH SERVICES CORPORATION
                              AND METPATH TPA, INC.
                                      INTO
                       CORNING CLINICAL LABORATORIES INC.
                            (a Michigan corporation)

     PLAN OF MERGER adopted as of June 30, 1996 by Corning Clinical Laboratories
Inc. ("CCL"), a business corporation of the State of Michigan, and by resolution
of its Board of Directors on said date, and adopted on June 30, 1996 by MetPath
Services Corporation ("MSC") and MetPath TPA, Inc. ("TPA"), each of which is a
business corporation of the State of Michigan, and by resolution of its Board of
Directors on said date.

1.      The Merger. MSC, TPA and CCL shall, pursuant to the provisions of the
Business Corporation Act of the State of Michigan ("BCA"), be merged with and
into a single corporation, to wit, CCL, which shall be the surviving corporation
upon the effective date of the merger and which is sometimes hereinafter
referred to as the "Surviving Corporation," and which shall continue to exist as
said Surviving Corporation under the provisions of the BCA. The separate
corporate existence of MSC and TPA shall cease upon said effective date of the
merger.

2.      Effective Time. The Merger shall become effective (the "Effective Time")
at 11:59 p.m. on August 31, 1996 or, if later, upon the filing of the
Certificate of Merger with the Secretary of State of Michigan in accordance with
the BCA.


                                       11





3.      Outstanding Shares. The number of outstanding shares of MSC is 1,000,
all of which are of one class and are common shares, and all of which are
entitled to vote. The number of outstanding shares of TPA is 1,000, all of which
are of one class and are common shares, and all of which are entitled to vote.

     The number of outstanding shares of CCL is 22,000, all of which are of one
class and are common shares, and all of which are entitled to vote.

4.      Articles of Incorporation of the Surviving Corporation. The Articles of
Incorporation of CCL as in effect immediately prior to the Effective Time shall,
until thereafter and further amended as provided therein and under the BCA, be
the Articles of Incorporation of the surviving corporation.

5.      By-Laws of the Surviving Corporation. The By-Laws of CCL as in effect
immediately prior to the Effective Time, shall, until thereafter and further
amended as provided therein and under the BCA, be the By-Laws of the Surviving
Corporation.

6.      Directors of the Surviving Corporation. The Directors of the Surviving
Corporation shall be the Directors of CCL immediately prior to the Effective
Time, until their respective successors are duly elected and qualified.


                                       12





7.      Officers of the Surviving Corporation. The Officers of the Surviving
Corporation shall be the Officers of CCL immediately prior to the Effective
Time, until the earlier of their resignation or removal or until their
respective successors are duly elected and qualified.

8.      Conversion of Shares. At the Effective Time, by virtue of the Merger and
without any action on the part of the holders thereof:

        (i) Each share of common stock of CCL issued and outstanding immediately
prior to the Effective Time shall remain outstanding and shall thereafter
evidence one validly issued, fully paid and nonassessable share of common stock
of the Surviving Corporation.

        (ii) Each outstanding share of Common Stock of MSC and TPA issued and
outstanding immediately prior to the Effective Time shall be canceled without
consideration.

9.      Rights and Liabilities of the Surviving Corporation. At and after the
Effective Time, the Surviving Corporation shall succeed to and possess, without
further act or deed, all of the estate, rights, privileges, powers, and
franchise, both public and private, and all of the property, real, personal, and
mixed, of each of MSC, TPA and CCL; all debts due to MSC and TPA shall be vested
in the Surviving Corporation; all claims, demands, property rights, privileges,
powers and franchises and every other interest of MSC and TPA shall be
effectively the property of the Surviving Corporation as they were of MSC and
TPA; the title

                                       13





to any real estate vested by deed or otherwise in MSC and TPA shall not revert
or be in any way impaired by reason of the Merger, but shall be vested in the
Surviving Corporation, all rights of creditors and all liens upon any property
of MSC and TPA shall be preserved unimpaired, limited to the property affected
by such lien at the Effective Time of the Merger; and all debts, liabilities,
and duties of MSC and TPA shall thenceforth attach to the Surviving Corporation
and may be enforced against it to the same extent as if such debts, liabilities
and duties had been incurred or contracted by it.

10.  Submission to Shareholders of MSC and TPA. This Plan of Merger shall be
submitted to the shareholders of MSC and TPA for their approval or rejection in
the manner prescribed by the BCA. This Plan of Merger is not required to be
submitted to the shareholders CCL for their approval.

11.  Abandonment of Merger.  This Plan of Merger may be terminated and abandoned
by joint action of the Board of Directors of CCL, MSC and TPA at any time prior
to Effective Time.

12.  Further Actions. The proper officers of CCL, MSC and TPA are hereby
authorized, empowered, and directed to do any and all acts and things, and to
make, execute, deliver, file and/or record any and all instruments, papers, and
documents which shall be or become necessary, proper, or convenient to carry out
or put into effect any of the provisions of this Plan of Merger or of the
Merger.

                                       14