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                                                                    Exhibit 4.22

                                PROMISSORY NOTE


                               DECEMBER 23, 1996

FOUR EMBARCADERO CENTER #3620              SAN FRANCISCO           CA


FOR VALUE RECEIVED, American Shared - Curacare ("Maker") promises, jointly and
severally if more than one, to pay to the order of GENERAL ELECTRIC COMPANY or
any subsequent holder hereof (each, a "Payee") at its office located at 20825
Swenson Drive, Waukesha, WI 53186 or at such other place as Payee may
designate, the principal sum of ONE MILLION SIX HUNDRED THIRTY-ONE THOUSAND FIVE
HUNDRED NINETY-FIVE AND 10/100 DOLLARS ($1,631,595.10), with interest on the
unpaid principal balance from and including the date hereof at the rate of TEN
AND 75/100 percent (10.75%) per annun, to be paid in lawful money of the United
States, in Sixty (60) consecutive monthly installments of principal and
interest of THIRTY-FOUR THOUSAND NINE HUNDRED FIFTY NINE AND 00/100 ($34,959.00)
and a final installment which shall be in the amount of the total outstanding
principal and interest.  The first installment shall be due and payable
JANUARY 1, 1997 and the following installments shall be due and payable on the
same day of each succeeding month (each, a "Payment Date").

All payments shall be applied first to interest and then to principal.  The
acceptance by Payee of any payment which is less than payment in full of all
amounts due and owing at such time shall not constitute a waiver of Payee's
right to receive payment in full at such time or at any prior or subsequent
time.  Interest shall be calculated on the basis of a 365 day year and will be
charged for each calendar day on which any principal is outstanding.

The Maker hereby expressly authorizes General Electric Company to insert the
date value is actually given in the blank space on the face hereof.

Time is of the essence hereof.  If any installment of principal and interest or
any other sum due under this Note is not received within ten (10) days after
the applicable Payment Date, the Maker agrees to pay in addition to the amount
of each such installment a late payment charge of five percent (5%) of said
installment, but not exceeding any lawful maximum.  In the event that (i) Maker
fails to make payment of any amount due hereunder within ten (10) days after
the same becomes due and payable; or (ii) Maker defaults or fails to perform
under any term or condition contained in any other agreement with Payee, then
the entire principal sum remaining unpaid, together with all interest thereon
and any other sum payable under this Note, at the election of Payee, shall
immediately become due and payable, with interest thereon at 20% per annum from
the date of such accelerated maturity until paid.

The Maker may prepay in full, but not in part, its entire indebtedness
hereunder upon payment of an additional sum as a premium equal to the following
percentages of the original principal balance for the indicated period:

Prior to the first annual anniversary date of this Note: five percent (5%)
Prior to the second annual anniversary date of this Note: four percent (4%)
Prior to the third annual anniversary date of this Note: three percent (3%)
Prior to the fourth annual anniversary date of this Note: two percent (2%)
Prior to the fifth annual anniversary date of this Note: one percent (1%) and
zero percent (0%) thereafter, plus all other sums due hereunder.

Your default under a Schedule by you or any entity managed or controlled by you
or by any principal of yours under any other agreement or contract with us,
regardless of when the agreement or contract was entered into, will, at our
sole option, if the default is not cured within ten days after written notice
of default, constitute a default of that Schedule and all other agreements and
contracts between you and/or such a principal or entity and us.
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It is the intention of the parties hereto to comply with the applicable usury
laws; accordingly, it is agreed that, notwithstanding any provision to the
contrary in this Note, in no event shall this Note require the payment or
permit the collection of interest in excess of the maximum amount permitted by
applicable law.  If any such excess interest is contracted for, charged or
received under this Note, or in the event that all of the principal balance
shall be prepaid, so that under any of such circumstances the amount of
interest contracted for, charged or received under this Note on the principal
balance shall exceed the maximum amount of interest permitted by applicable
law, then in such event (a) the provisions of this paragraph shall govern and
control, (b) neither Maker nor any other person or entity now or hereafter
liable for the payment hereof shall be obligated to pay the amount of such
interest to the extent that it is in excess of the maximum amount of interest
permitted by applicable law, (c) any such excess which may have been collected
shall be either applied as a credit against the then unpaid principal balance
or refunded to Maker, at the option of the Payee, and (d) the effective rate of
interest shall be automatically reduced to the maximum lawful contract rate
allowed under applicable law as now or hereafter construed by the courts having
jurisdiction thereof.

It is further agreed that without limitation of the foregoing, all calculations
of the rate of interest contracted for, charged or received under this Note
which are made for the purpose of determining whether such rate exceeds the
maximum lawful contract rate, shall be made, to the extent permitted by
applicable law, by amortizing, prorating, allocating and spreading in equal
parts during the period of the full stated term of the indebtedness evidenced
hereby, all interest at any time contracted for, charged or received from Maker
or otherwise by Payee in connection with such indebtedness; provided, however,
that if any applicable state law is amended or the law of the United States of
America preempts any applicable state law, so that it becomes lawful for the
Payee to receive a greater simple interest per annum rate that is presently
allowed, the Maker agrees that, on the effective date of such amendment or
preemption, as the case may be, the lawful maximum hereunder shall be increased
to the maximum simple interest per annum rate allowed by the higher of the
amended state law or the law of the United States of America.

The Maker and all sureties, endorsers, guarantors or any others (each such
person, other than the Maker, an "Obligor") who may at any time become liable
for the payment hereof jointly and severally consent hereby to any and all
extensions of time, renewals, waivers or modifications of, and all
substitutions or releases of any party primarily or secondarily liable on this
Note or any term and provision hereof, which may be made, granted or consented
to by Payee, and agree that suit may be brought and maintained against any one
or more of them, which may be made, granted or consented to by Payee, and agree
that suit may be brought and maintained against any one or more of them, at the
election of Payee without joinder of any other as a party thereto.  The Maker
and each Obligor hereby waives presentment, demand for payment, notice of
nonpayment, protest, notice of protest, notice of dishonor, and all other
notices in connection herewith, as well as filing of suit (if permitted by law)
and diligence in collecting this Note, and agrees to pay (if permitted by law)
all expenses incurred in collection, including Payee's actual attorneys' fees.
Maker and each Obligor agrees that fees not in excess of twenty percent (20%)
of the amount then due shall be deemed reasonable.  Maker and Obligor hereby
waives all benefits of valuation, appraisement, and exemption laws.

American Shared - CuraCare
A California partnership


                                           
   /s/ Richard Magary                         By:      /s/ Ernest A. Bates                        (Seal)
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Witness                                            Ernest A. Bates, M.D., Chairman and CEO
                                                   American Shared Hospital Services, general partner



                                               ACKNOWLEDGED: GENERAL ELECTRIC COMPANY

                                               By:     /s/ R. Schueller                          (Seal)
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Witness                                             Signature

                                                           R. Schueller                                      
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                                                    Print name (and title, if applicable)