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                                                                   EXHIBIT 10.65


                                 PROMISSORY NOTE


$500,000                                                         August 18, 1997


               FOR VALUE RECEIVED, the undersigned, ACCUMED INTERNATIONAL, INC.,
a Delaware corporation (together with its successors and assigns, "Maker"),
HEREBY UNCONDITIONALLY PROMISES TO PAY to the order of ROBERT L. PRIDDY, an
individual (together with his successors and assigns, "Payee"), at 3435
Kingsboro Road #1601, Atlanta, Georgia 30326, or at such other place as the
holder of this Promissory Note (this "Note") may from time to time designate in
writing, in lawful money of the United States of America and in immediately
available funds, the principal sum of FIVE HUNDRED THOUSAND AND NO/100 DOLLARS
($500,000.00), together with interest on the unpaid principal balance at the
rate of twelve percent (12%) per annum, from the date hereof until the principal
amount is paid in full.

               The unpaid principal balance of this Note, together with all
accrued and unpaid interest thereon, shall be paid in full on the earlier of (i)
October 15, 1997 and (ii) the closing of a senior debt financing with a
financial institution (other than Heller Financial, Inc.) in which Maker
receives at least $1,000,000 in gross loan proceeds (the "Maturity Date"). This
Note may be prepaid in whole at any time, however, should the Note be prepaid
prior to the Maturity Date, Maker will pay a prepayment penalty equal to the
difference between Ten Thousand Dollars ($10,000) and the amount of accrued and
unpaid interest at the time of the prepayment.

               In the event the interest paid hereunder exceeds the maximum rate
of interest permitted by applicable law, such excess shall be applied toward the
repayment of the principal amount of this Note, and any further excess shall be
paid over to Maker after satisfaction in full of the outstanding principal
balance hereof. Maker further agrees to pay on demand all costs and expenses
(including, without limitation, reasonable attorneys' fees) incurred by Payee or
its representatives in connection with the collection or enforcement of Maker's
obligations hereunder.

               All payments and prepayments received by Payee hereunder shall be
applied first to all unpaid costs and expenses payable by Maker hereunder,
second to all accrued and unpaid interest hereunder, and third to the unpaid
principal balance hereof.

               Each of the following shall constitute an "Event of Default"
under this Note:

                (1) Maker fails to pay when due, whether by acceleration or
        otherwise, any payment required under this Note within five (5) days
        after the date on which such payment is due;



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               (2) Maker shall (i) cease to do business as a going concern, (ii)
        generally fail to meet its obligations as they mature, (iii) file a
        petition or request for reorganization or protection or relief under the
        bankruptcy laws of the United States or any state or territory thereof,
        (iv) make any general assignment for the benefit of creditors, (v)
        consent to the appointment of a receiver or trustee, including a
        custodian under the United States bankruptcy laws, whether such receiver
        or trustee is appointed in a voluntary or involuntary proceeding, or
        (vi) permit a request or petition for liquidation, reorganization or
        other relief under the bankruptcy laws of the United States, or any
        state thereof, or any other type of insolvency proceedings, to not be
        vacated or dismissed within sixty (60) days after such event, whether
        such filing or petition is voluntary or involuntary;

               (3) A default occurs under any agreement, document or instrument
        delivered in connection herewith, or if Maker fails to perform or keep
        any of the other covenants, agreements or warranties contained herein or
        therein and fails to cure the same within ten (10) business days after
        notice from Payee to cure, unless a shorter or longer time period is
        expressly specified in any particular covenant, agreement or warranty;

               (4) An event of default occurs under any other agreement pursuant
        to which Maker has incurred obligations for monies owed in a principal
        amount in excess of $1,000,000 and such event of default results in the
        right to accelerate such obligations, or an event of default occurs
        under any other material agreement to which Maker is a party or by which
        it is bound and such event of default results in Maker becoming
        obligated to pay an amount in excess of $1,000,000; or

               (5) The execution, without Payee's prior written consent, of any
        agreement to merge or consolidate Maker with any other form of business
        entity or to sell a substantial portion of the assets of Maker.

In the event that any Event of Default described above shall occur, Payee, in
its sole discretion, may declare all obligations and liabilities of Maker due
and payable, whereupon all of the obligations and liabilities of Maker shall be
immediately due and payable. Payee shall promptly advise Maker of any such
declaration, but failure to do so shall not impair the effect of such
declaration.

               Payee's failure at any time or times hereafter to require strict
performance by Maker of any of the provisions, terms and conditions contained in
this Note or in any other agreement, instrument or document, now or at any time
or times hereafter, executed by Maker or any third party and delivered to Payee
or its representative, shall not waive, affect or diminish any right of Payee at
any time or times hereafter to demand strict performance thereof and such right
shall not be deemed to have been waived by any act or knowledge of Payee, its
agents or representatives, unless such waiver is contained in an instrument in
writing signed by the executor of Payee and directed to Maker specifying such
waiver. No waiver by or on behalf of Payee of any Event of Default or any event
which, with the giving of notice or the



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passage of time, or both, would become an Event of Default (a "Potential Event
of Default") shall operate as a waiver of any other Event of Default or
Potential Event of Default or the same Event of Default or Potential Event of
Default on a future occasion. No delay on the part of Payee or its
representatives in the exercise of any right or remedy shall operate as a waiver
thereof, and no single or partial exercise by Payee or its representatives of
any right or remedy shall preclude other or further exercise thereof or the
exercise of any other right or remedy.

               To the extent not waived in the preceding two paragraphs, demand,
presentment, protest and notice of nonpayment and protest are hereby waived by
Maker.

               Maker also irrevocably waives all of its now existing and
hereafter arising rights to set-off any amounts owing to Payee under this Note,
or otherwise, against any amounts now or hereafter owing by Payee or its
representatives to Maker.

               Whenever in this Note reference is made to Payee or Maker, such
reference shall be deemed to include, as applicable, a reference to their
respective successors and assigns. The provisions of this Note shall be binding
upon and shall inure to the benefit of said successors and assigns. Maker's
successors and assigns shall include, without limitation, a receiver, trustee or
debtor-in-possession of or for Maker.

               THIS NOTE SHALL BE CONSTRUED IN ALL RESPECTS IN
ACCORDANCE WITH, AND GOVERNED BY, THE LAWS AND DECISIONS OF THE
STATE OF ILLINOIS.

                MAKER CONSENTS TO THE JURISDICTION OF ANY STATE OR FEDERAL COURT
LOCATED WITHIN THE STATE OF ILLINOIS, AND MAKER HEREBY WAIVES PERSONAL SERVICE
OF ANY AND ALL PROCESS UPON MAKER AND CONSENTS THAT ALL SUCH SERVICE OF PROCESS
BE MADE BY CERTIFIED OR REGISTERED MAIL DIRECTED TO MAKER AT ITS ADDRESS STATED
IN THE FIRST PARAGRAPH OF THIS NOTE. SERVICE SO MADE SHALL BE DEEMED TO BE
COMPLETED FIVE (5) DAYS AFTER THE SAME SHALL HAVE BEEN POSTED.

               EACH OF MAKER AND PAYEE WAIVES TRIAL BY JURY AND WAIVES
ANY OBJECTION TO VENUE OF ANY ACTION INSTITUTED HEREUNDER AND
CONSENTS TO THE GRANTING OF SUCH LEGAL OR EQUITABLE RELIEF AS IS
DEEMED APPROPRIATE BY THE COURT.



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               Whenever possible each provision of this Note shall be
interpreted in such manner as to be effective and valid under applicable law,
but if any provision of this Note shall be prohibited by or invalid under
applicable law, such provision shall be ineffective to the extent of such
prohibition or invalidity, without invalidating the remainder of such provision
or the remaining provisions of this Note.


                                        ACCUMED INTERNATIONAL, INC.



                                        By: \S\ LEONARD R. PRANGE
                                        Name: Leonard R. Prange
                                        Title:  Chief Financial Officer and
                                                Chief Operating Officer



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