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                                                                   EXHIBIT 10.33

                                PROMISSORY NOTE

U.S. $500,000.00                                               February 11, 1997

1.       ACCUMED INTERNATIONAL, INC., a corporation duly incorporated and
existing under the laws of the State of Delaware, United States of America,
having its principal office at 900 N. Franklin, Suite 401, Chicago, Illinois,
U.S.A., 60610 (the "Debtor"), hereby promises to pay to or to the order of
ONCOMETRICS IMAGING CORP., a corporation duly continued and existing under the
laws of the Yukon Territory (the "Lender"), having its principal office at 505
- 601 West Broadway Street, Vancouver, British Columbia, V5Z 4C2, or such other
place as the Lender may designate in writing, in lawful money of the United
States of America, the principal sum of FIVE HUNDRED THOUSAND (U.S.$500,000.00)
U.S.  DOLLARS with interest on the unpaid principal amount outstanding from
time to time on the terms and conditions herein set forth.

2.       This Note shall bear interest at the U.S. Prime Rate (as hereinafter
defined), calculated and compounded monthly, not in advance, commencing from
and including the date hereof (the "Interest Rate").  "U.S. Prime Rate" means
the annual rate of interest announced from time to time by The Canadian
Imperial Bank of Commerce as a reference rate then in effect for determining
interest rates on U.S. dollar commercial loans made in Canada.

3.       Principal and interest on this Note shall be paid as follows:

         (a)     accrued interest at the Interest Rate shall be due and payable
                 on the last day of each and every calendar month, commencing
                 the month following the date of this Note, until the entire
                 principal balance and all accrued interest are paid in full;
                 and

         (b)     the entire principal balance and all accrued interest shall be
                 due and payable in full on May 12, 1997.

4.               The Debtor shall have the right to prepay this Note in full or
                 in part at any time and from time to time without penalty.

5.               This Note shall be in default, and all principal and accrued
interest then outstanding shall be immediately due and payable, if the payment
of any principal and/or accrued interest hereunder is not made when due or upon
the occurrence of any one or more of the following events:

         (a)     the Debtor fails to observe or perform any covenant,
                 agreement, condition or obligation in favour of the Lender,
                 whether or not contained in this Note or in the security
                 agreement between the Lender and Debtor of even date herewith
                 (the "Security Agreement"), including a failure to pay any
                 amount owing hereunder when due;


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         (b)     any representation, warranty or statement made by or on behalf
                 of the Debtor to the Lender is incorrect in any material
                 respect as of the date made;

         (c)     the Debtor is in default under, or in material breach of any
                 of the terms of, any agreement, instrument or document in
                 favour of the Lender, the Debtor's bank or any other creditor
                 of the Debtor, including, without limitation, the Security
                 Agreement;

         (d)     the Debtor ceases or threatens to cease to carry on the
                 Debtor's business, or any material part thereof, or commits or
                 threatens to commit an act of bankruptcy;

         (e)     a receiver, receiver manager, trustee or similar official of
                 all or any part of the property of the Debtor is appointed;

         (f)     the Debtor becomes insolvent or files a proposal, a notice of
                 intention to file a proposal, or an assignment for the benefit
                 of creditors under applicable bankruptcy or similar
                 legislation, or a petition is filed, an order is made, a
                 resolution is passed, or any other step is taken for the
                 bankruptcy, liquidation, dissolution, winding-up or
                 reorganization of the Debtor or for any arrangement or
                 composition of the debts of the Debtor;

         (g)     the Lender believes in good faith and upon commercially
                 reasonable grounds that the prospect of payment of any amount
                 owing hereunder, or the performance of any other obligation of
                 the Debtor under this Note or the Security Agreement, is or is
                 about to be impaired or that there has been a material adverse
                 change in the condition, financial or otherwise, of the
                 Debtor; or

         (h)     the occurrence of any event of default under the Security
                 Agreement.

6.       Failure to exercise any right the Lender may have or be entitled to in
the event of any default hereunder shall not constitute a waiver of such right
or any other right in the event of any subsequent default.

7.       The Debtor hereby waives presentment for payment, protest and demand,
notice of protest, demand, dishonor and nonpayment of this Note.  In any action
or proceeding to recover any sum herein provided for, no defense of adequacy of
security or that resort must first be had to security or to any other person
shall be asserted.

8.       The obligation of the Debtor to pay each of the amounts owing
hereunder is absolute and unconditional and will not be affected by any
circumstance, including any set-off, claim, counterclaim, defence or other
right which the Debtor now or hereafter has against the Lender or anyone else
for any reason whatsoever.

9.       The taking of a judgment against the Debtor on any of the agreements
herein contained will not operate as a merger of those agreements or affect the
Lender's right to recover the amounts owing hereunder (including interest at
the rate payable thereon).

10.      Time is of the essence of this Note and each of the obligations
evidenced hereby.


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11.      This Note may only be amended by a document executed by both the
Lender and the Debtor.

12.      The Debtor agrees to pay all costs, including reasonable legal fees on
a solicitor and own client basis, incurred by the Lender in connection with the
preparation, enforcement or collection of this Note, the Security Agreement or
any other agreements or documents relating hereto.

13.      Any notices, requests, demands or other communications required or
permitted to be sent hereunder or under any related document shall be delivered
personally, sent by telefax, sent by overnight courier or mailed by registered
or certified mail, return receipt requested, to such address as set out on page
one of this Note or such other address either party hereto shall from time to
time notify the other, and shall be deemed to have been received on the day of
personal delivery, when sent by telefax on the day when confirmation is
received, one (1) business day after deposit with an overnight domestic courier
or five (5) days after deposit in the mail, as the case may be.

14.      This Note shall be governed by and construed in accordance with the
laws of the Province of British Columbia and the laws of Canada applicable
therein.  The Debtor and Lender hereby irrevocably attorn to the jurisdiction
of the courts of the Province of British Columbia and consent to service of
process in any manner authorized by British Columbia law.

15.      This Note shall be binding upon and enure to the benefit of the Lender
and Debtor and their respective successors and assigns.

16.      The Lender has not made any representation or agreement or undertaken
any obligation in connection with the subject matter of this Note other than as
specifically set out herein.

         DATED February 11, 1997.

                          ACCUMED INTERNATIONAL, INC.


                                        By:/s/ Peter P. Gombrich 
                                           -------------------------------------
                                           Authorized Signatory

                                        By:/s/ Leonard R. Prange 
                                           -------------------------------------
                                           Authorized Signatory





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