<PAGE>   1
                                                                   EXHIBIT 10.74


THIS WARRANT AND THE SHARES OF COMMON STOCK INTO WHICH IT IS EXERCISABLE HAVE
NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 (THE "ACT") NOR UNDER ANY
STATE SECURITIES LAW AND MAY NOT BE PLEDGED, SOLD, ASSIGNED OR OTHERWISE
TRANSFERRED UNTIL A (1) REGISTRATION STATEMENT UNDER THE ACT AND ANY APPLICABLE
STATE SECURITIES LAW HAS BECOME EFFECTIVE WITH RESPECT THERETO, OR (2) RECEIPT
BY THE COMPANY OF AN OPINION OF COUNSEL TO THE COMPANY TO THE EFFECT THAT
REGISTRATION UNDER THE ACT OR APPLICABLE STATE SECURITIES LAW IS NOT REQUIRED IN
CONNECTION WITH THE PROPOSED TRANSFER.


             Void after 5:00 p.m. New York Time, on March 23, 2005.
               Warrant to Purchase 350,000 Shares of Common Stock.


                        WARRANT TO PURCHASE COMMON STOCK

                                       OF

                           ACCUMED INTERNATIONAL, INC.



               This is to Certify That, FOR VALUE RECEIVED, Commonwealth
Associates, or assigns ("Holder"), is entitled to purchase, subject to the
provisions of this Warrant, from AccuMed International, Inc., a Delaware
corporation ("Company"), 350,000 fully paid, validly issued and nonassessable
shares of Common Stock, par value $.01 per share, of the Company ("Common
Stock") at a price of $0.75 per share at any time or from time to time during
the period from the Initial Warrant Exercise Date (defined below) to March 23,
2005, but not later than 5:00 p.m. New York City Time, on March 23, 2005. The
number of shares of Common Stock to be received upon the exercise of this
Warrant and the price to be paid for each share of Common Stock may be adjusted
from time to time as hereinafter set forth. The shares of Common Stock
deliverable upon such exercise, and as adjusted from time to time, are
hereinafter sometimes referred to as "Warrant Shares" and the exercise price of
a share of Common Stock in effect at any time and as adjusted from time to time
is hereinafter sometimes referred to as the "Exercise Price". This Warrant,
together with warrants of like tenor, constituting in the aggregate warrants
(the "Warrants") to purchase up to 350,000 shares of Common Stock, is being
issued in exchange for the cancellation of the repriced warrants issued in
exchange for the warrants was originally issued pursuant to an agency agreement
dated February 27, 1998 between the



<PAGE>   2

Company and Commonwealth Associates ("Commonwealth"), in connection with a
private placement ("Private Placement") through Commonwealth of the Units of the
Company.

                      (a) EXERCISE OF WARRANT.

                      (1) This Warrant may be exercised in whole or in part at
any time or from time to time on or after the date of this Warrant ("Initial
Warrant Exercise Date") and until March 23, 2005 (the "Exercise Period"),
subject to the provisions of Section (j)(2) hereof; provided, however, that if
either such day is a day on which banking institutions in the State of New York
are authorized by law to close, then on the next succeeding day which shall not
be such a day. This Warrant may be exercised by presentation and surrender
hereof to the Company at its principal office, or at the office of its stock
transfer agent, if any, with the Purchase Form annexed hereto duly executed and
accompanied by payment of the Exercise Price for the number of Warrant Shares
specified in such form. As soon as practicable after each such exercise of the
warrants, but not later than seven (7) days from the date of such exercise, the
Company shall issue and deliver to the Holder a certificate or certificate for
the Warrant Shares issuable upon such exercise, registered in the name of the
Holder or its designed. If this Warrant should be exercised in part only, the
Company shall, upon surrender of this Warrant for cancellation, execute and
deliver a new Warrant evidencing the rights of the Holder thereof to purchase
the balance of the Warrant Shares purchasable thereunder. Upon receipt by the
Company of this Warrant at its office, or by the stock transfer agent of the
Company at its office, in proper form for exercise, the Holder shall be deemed
to be the holder of record of the shares of Common Stock issuable upon such
exercise, notwithstanding that the stock transfer books of the Company shall
then be closed or that certificates representing such shares of Common Stock
shall not then be physically delivered to the Holder.

                      (2) At any time during the Exercise Period, the Holder
may, at its option, exchange this Warrant, in whole or in part (a "Warrant
Exchange"), into the number of Warrant Shares determined in accordance with this
Section (a)(2), by surrendering this Warrant at the principal office of the
Company or at the office of its stock transfer agent, accompanied by a notice
stating such Holder's intent to effect such exchange, the number of Warrant
Shares to be exchanged and the date on which the Holder requests that such
Warrant Exchange occur (the "Notice of Exchange"). The Warrant Exchange shall
take place on the date specified in the Notice of Exchange or, if later, the
date the Notice of Exchange is received by the Company (the "Exchange Date").
Certificates for the shares issuable upon such Warrant Exchange and, if
applicable, a new warrant of like tenor evidencing the balance of the shares
remaining subject to this Warrant, shall be issued as of the Exchange Date and
delivered to the Holder within seven (7) days following the Exchange Date. In
connection with any Warrant Exchange, this Warrant shall represent the right to
subscribe for and acquire the number of Warrant Shares (rounded to the next
highest integer) equal to (i) the number of Warrant Shares specified by the
Holder in its Notice of Exchange (the "Total Number") less (ii) the number of
Warrant Shares equal to the quotient obtained by dividing (A) the product of the
Total Number and the existing Exercise Price by (B) the current market value of
a share of Common Stock. Current market value shall have the meaning set forth
Section (c) below, except that for purposes hereof, the date of exercise, as
used in such Section (c), shall mean the Exchange Date.



                                        3

<PAGE>   3




               (b) RESERVATION OF SHARES. The Company shall at all times reserve
for issuance and/or delivery upon exercise of this Warrant such number of shares
of its Common Stock as shall be required for issuance and delivery upon exercise
of this Warrant.

               (c) FRACTIONAL SHARES. No fractional shares or script
representing fractional shares shall be issued upon the exercise of this
Warrant. With respect to any fraction of a share called for upon any exercise
hereof, the Company shall pay to the Holder an amount in cash equal to such
fraction multiplied by the current market value of a share, determined as
follows:

                      (1) If the Common Stock is listed on a national securities
               exchange or admitted to unlisted trading privileges on such
               exchange or listed for trading on the Nasdaq National Market, the
               current market value shall be the last reported sale price of the
               Common Stock on such exchange or market on the last business day
               prior to the date of exercise of this Warrant or if no such sale
               is made on such day, the average closing bid and asked prices for
               such day on such exchange or market; or

                      (2) If the Common Stock is not so listed or admitted to
               unlisted trading privileges, but is traded on the Nasdaq SmallCap
               Market, the current Market Value shall be the average of the
               closing bid and asked prices for such day on such market and if
               the Common Stock is not so traded, the current market value shall
               be the mean of the last reported bid and asked prices reported by
               the National Quotation Bureau, Inc. on the last business day
               prior to the date of the exercise of this Warrant; or

                      (3) If the Common Stock is not so listed or admitted to
               unlisted trading privileges and bid and asked prices are not so
               reported, the current market value shall be an amount, not less
               than book value thereof as at the end of the most recent fiscal
               year of the Company ending prior to the date of the exercise of
               the Warrant, determined in such reasonable manner as may be
               prescribed by the Board of Directors of the Company.

               (d)    EXCHANGE, TRANSFER, ASSIGNMENT OR LOSS OF
WARRANT. This Warrant is exchangeable, without expense, at the option of the
Holder, upon presentation and surrender hereof to the Company or at the office
of its stock transfer agent, if any, for other warrants of different
denominations entitling the holder thereof to purchase in the aggregate the same
number of shares of Common Stock purchasable hereunder. Upon surrender of this
Warrant to the Company at its principal office or at the office of its stock
transfer agent, if any, with the Assignment Form annexed hereto duly executed
and funds sufficient to pay any transfer tax, the Company shall, without charge,
execute and deliver a new Warrant in the name of the assignee named in such
instrument of assignment and this Warrant shall promptly be cancelled. This
Warrant may be divided or combined with other warrants which carry the same
rights upon



                                       3

<PAGE>   4

presentation hereof at the principal office of the Company or at the office of
its stock transfer agent, if any, together with a written notice specifying the
names and denominations in which new Warrants are to be issued and signed by the
Holder hereof. The term "Warrant" as used herein includes any Warrants into
which this Warrant may be divided or exchanged. Upon receipt by the Company of
evidence satisfactory to it of the loss, theft, destruction or mutilation of
this Warrant, and (in the case of loss, theft or destruction) of reasonably
satisfactory indemnification, and upon surrender and cancellation of this
Warrant, if mutilated, the Company will execute and deliver a new Warrant of
like tenor and date. Any such new Warrant executed and delivered shall
constitute an additional contractual obligation on the part of the Company,
whether or not this Warrant so lost, stolen, destroyed, or mutilated shall be at
any time enforceable by anyone.

               (e) RIGHTS OF THE HOLDER. The Holder shall not, by virtue hereof,
be entitled to any rights of a shareholder in the Company, either at law or
equity, and the rights of the Holder are limited to those expressed in the
Warrant and are not enforceable against the Company except to the extent set
forth herein.

               (f) ANTI-DILUTION PROVISIONS. The Exercise Price in effect at any
time and the number and kind of securities purchasable upon the exercise of the
Warrants shall be subject to adjustment from time to time upon the happening of
certain events as follows:

                      (1) In case the Company shall (i) declare a dividend or
               make a distribution on its outstanding shares of Common Stock in
               shares of Common Stock, (ii) subdivide or reclassify its
               outstanding shares of Common Stock into a greater number of
               shares, or (iii) combine or reclassify its outstanding shares of
               Common Stock into a smaller number of shares, the Exercise Price
               in effect at the time of the record date for such dividend or
               distribution or of the effective date of such subdivision,
               combination or reclassification shall be adjusted so that it
               shall equal the price determined by multiplying the Exercise
               Price by a fraction, the denominator of which shall be the number
               of shares of Common Stock outstanding after giving effect to such
               action, and the numerator of which shall be the number of shares
               of Common Stock outstanding immediately prior to such action.
               Such adjustment shall be made successively whenever any event
               listed above shall occur.

                      (2) In case the Company shall fix a record date for the
               issuance of rights or warrants to all holders of its Common Stock
               entitling them to subscribe for or purchase shares of Common
               Stock (or securities convertible into Common Stock) at a price
               (the "Subscription Price") (or having a conversion price per
               share) less than the current market price of the Common Stock (as
               defined in Subsection (8) below) on the record date mentioned
               below, or less than the Exercise Price on such record date the
               Exercise Price shall be adjusted so that the same shall equal the
               lower of (i) the price determined by multiplying the Exercise



                                       4

<PAGE>   5

               Price in effect immediately prior to the date of such issuance by
               a fraction, the numerator of which shall be the sum of the number
               of shares of Common Stock outstanding on the record date
               mentioned below and the number of additional shares of Common
               Stock which the aggregate offering price of the total number of
               shares of Common Stock so offered (or the aggregate conversion
               price of the convertible securities so offered) would purchase at
               such current market price per share of the Common Stock, and the
               denominator of which shall be the sum of the number of shares of
               Common Stock outstanding on such record date and the number of
               additional shares of Common Stock offered for subscription or
               purchase (or into which the convertible securities so offered are
               convertible) or (ii) in the event the Subscription Price is equal
               to or higher than the current market price but is less than the
               Exercise Price, the price determined by multiplying the Exercise
               Price in effect immediately prior to the date of issuance by a
               fraction, the numerator of which shall be the sum of the number
               of shares outstanding on the record date mentioned below and the
               number of additional shares of Common Stock which the aggregate
               offering price of the total number of shares of Common Stock so
               offered (or the aggregate conversion price of the convertible
               securities so offered) would purchase at the Exercise Price in
               effect immediately prior to the date of such issuance, and the
               denominator of which shall be the sum of the number of shares of
               Common Stock outstanding on the record date mentioned below and
               the number of additional shares of Common Stock offered for
               subscription or purchase (or into which the convertible
               securities so offered are convertible). Such adjustment shall be
               made successively whenever such rights or warrants are issued and
               shall become effective immediately after the record date for the
               determination of shareholders entitled to receive such rights or
               warrants; and to the extent that shares of Common Stock are not
               delivered (or securities convertible into Common Stock are not
               delivered) after the expiration of such rights or warrants the
               Exercise Price shall be readjusted to the Exercise Price which
               would then be in effect had the adjustments made upon the
               issuance of such rights or warrants been made upon the basis of
               delivery of only the number of shares of Common Stock (or
               securities convertible into Common Stock) actually delivered.

                      (3) In case the Company shall hereafter distribute to the
               holders of its Common Stock evidences of its indebtedness or
               assets (excluding cash dividends or distributions and dividends
               or distributions referred to in Subsection (1) above) or
               subscription rights or warrants (excluding those referred to in
               Subsection (2) above), then in each such case the Exercise Price
               in effect thereafter shall be determined by multiplying the
               Exercise Price in effect immediately prior thereto by a fraction,
               the numerator of which shall be the total number of shares of
               Common Stock outstanding multiplied by the current market price
               per share of Common Stock (as defined in Subsection (8) below),
               less the fair market value (as determined by the Company's Board
               of Directors) of said assets or evidences of



                                       5

<PAGE>   6

               indebtedness so distributed or of such rights or warrants, and
               the denominator of which shall be the total number of shares of
               Common Stock outstanding multiplied by such current market price
               per share of Common Stock. Such adjustment shall be made
               successively whenever such a record date is fixed. Such
               adjustment shall be made whenever any such distribution is made
               and shall become effective immediately after the record date for
               the determination of shareholders entitled to receive such
               distribution.

                      (4) In case the Company shall issue shares of its Common
               Stock [excluding shares issued (i) in any of the transactions
               described in Subsection (1) above, (ii) upon exercise of options
               granted to the Company's employees under a plan or plans adopted
               by the Company's Board of Directors and approved by its
               shareholders, if such shares would otherwise be included in this
               Subsection (4), (but only to the extent that the aggregate number
               of shares excluded hereby and issued after the date hereof, shall
               not exceed 5% of the Company's Common Stock outstanding at the
               time of any issuance), (iii) upon exercise of options and
               warrants outstanding at March 23, 1998, and this Warrant (iv) to
               shareholders of any corporation which merges into the Company in
               proportion to their stock holdings of such corporation
               immediately prior to such merger, upon such merger, or (v) issued
               in a bona fide public offering pursuant to a firm commitment
               underwriting, but only if no adjustment is required pursuant to
               any other specific subsection of this Section (f) (without regard
               to Subsection (9) below) with respect to the transaction giving
               rise to such rights] for a consideration per share (the "Offering
               Price") less than the current market price per share [as defined
               in Subsection (8) below] on the date the Company fixes the
               offering price of such additional shares or less than the
               Exercise Price, the Exercise Price shall be adjusted immediately
               thereafter so that it shall equal the lower of (i) the price
               determined by multiplying the Exercise Price in effect
               immediately prior thereto by a fraction, the numerator of which
               shall be the sum of the number of shares of Common Stock
               outstanding immediately prior to the issuance of such additional
               shares and the number of shares of Common Stock which the
               aggregate consideration received [determined as provided in
               Subsection (7) below] for the issuance of such additional shares
               would purchase at such current market price per share of Common
               Stock, and the denominator of which shall be the number of shares
               of Common Stock outstanding immediately after the issuance of
               such additional shares or (ii) in the event the Offering Price is
               equal to or higher than the current market price per share but
               less than the Exercise Price, the price determined by multiplying
               the Exercise Price in effect immediately prior to the date of
               issuance by a fraction, the numerator of which shall be the
               number of shares of Common Stock outstanding immediately prior to
               the issuance of such additional shares and the number of shares
               of Common Stock which the aggregate consideration received
               [determined as provided in subsection (7) below] for the issuance
               of such additional shares would purchase at the Exercise Price in
               effect



                                       6

<PAGE>   7

               immediately prior to the date of such issuance, and the
               denominator of which shall be the number of shares of Common
               Stock outstanding immediately after the issuance of such
               additional shares. Such adjustment shall be made successively
               whenever such an issuance is made.

                      (5) In case the Company shall issue any securities
               convertible into or exchangeable for its Common Stock [excluding
               securities issued in transactions described in Subsections (2)
               and (3) above] for a consideration per share of Common Stock (the
               "Conversion Price") initially deliverable upon conversion or
               exchange of such securities [determined as provided in Subsection
               (7) below] less than the current market price per share [as
               defined in Subsection (8) below] in effect immediately prior to
               the issuance of such securities, or less than the Exercise Price,
               the Exercise Price shall be adjusted immediately thereafter so
               that it shall equal the lower of (i) the price determined by
               multiplying the Exercise Price in effect immediately prior
               thereto by a fraction, the numerator of which shall be the sum of
               the number of shares of Common Stock outstanding immediately
               prior to the issuance of such securities and the number of shares
               of Common Stock which the aggregate consideration received
               [determined as provided in Subsection (7) below] for such
               securities would purchase at such current market price per share
               of Common Stock, and the denominator of which shall be the sum of
               the number of shares of Common Stock outstanding immediately
               prior to such issuance and the maximum number of shares of Common
               Stock of the Company deliverable upon conversion of or in
               exchange for such securities at the initial conversion or
               exchange price or rate or (ii) in the event the Conversion Price
               is equal to or higher than the current market price per share but
               less than the Exercise Price, the price determined by multiplying
               the Exercise Price in effect immediately prior to the date of
               issuance by a fraction, the numerator of which shall be the sum
               of the number of shares outstanding immediately prior to the
               issuance of such securities and the number of shares of Common
               Stock which the aggregate consideration received [determined as
               provided in subsection (7) below] for such securities would
               purchase at the Exercise Price in effect immediately prior to the
               date of such issuance, and the denominator of which shall be the
               sum of the number of shares of Common Stock outstanding
               immediately prior to the issuance of such securities and the
               maximum number of shares of Common Stock of the Company
               deliverable upon conversion of or in exchange for such securities
               at the initial conversion or exchange price or rate. Such
               adjustment shall be made successively whenever such an issuance
               is made.

                      (6) Whenever the Exercise Price payable upon exercise of
               each Warrant is adjusted pursuant to Subsections (1), (2), (3),
               (4) and (5) above, the number of Warrant Shares purchasable upon
               exercise of this Warrant shall simultaneously be adjusted by
               multiplying the number of Warrant Shares initially



                                       7

<PAGE>   8

               issuable upon exercise of this Warrant by the Exercise Price in
               effect on the date hereof and dividing the product so obtained by
               the Exercise Price, as adjusted.

                      (7) For purposes of any computation respecting
               consideration received pursuant to Subsections (4) and (5) above,
               the following shall apply:

                             (A) in the case of the issuance of shares of Common
                      Stock for cash, the consideration shall be the amount of
                      such cash, provided that in no case shall any deduction be
                      made for any commissions, discounts or other expenses
                      incurred by the Company for any underwriting of the issue
                      or otherwise in connection therewith;

                             (B) in the case of the issuance of shares of Common
                      Stock for a consideration in whole or in part other than
                      cash, the consideration other than cash shall be deemed to
                      be the fair market value thereof as determined in good
                      faith by the Board of Directors of the Company
                      (irrespective of the accounting treatment thereof), whose
                      determination shall be conclusive; and

                             (C) in the case of the issuance of securities
                      convertible into or exchangeable for shares of Common
                      Stock, the aggregate consideration received therefor shall
                      be deemed to be the consideration received by the Company
                      for the issuance of such securities plus the additional
                      minimum consideration, if any, to be received by the
                      Company upon the conversion or exchange thereof [the
                      consideration in each case to be determined in the same
                      manner as provided in clauses (A) and (B) of this
                      Subsection (7)].

                      (8) For the purpose of any computation under Subsections
               (2), (3), (4) and (5) above, the current market price per share
               of Common Stock at any date shall be determined in the manner set
               forth in Section (c) hereof except that the current market price
               per share shall be deemed to be the higher of (i) the average of
               the prices for 30 consecutive trading days before such date or
               (ii) the price on the trading day immediately preceding such
               date.

                      (9) No adjustment in the Exercise Price shall be required
               unless such adjustment would require an increase or decrease of
               at least five cents ($0.05) in such price; provided, however,
               that any adjustments which by reason of this Subsection (9) are
               not required to be made shall be carried forward and taken into
               account in any subsequent adjustment required to be made
               hereunder. All calculations under this Section (f) shall be made
               to the nearest cent or to the nearest one-hundredth of a share,
               as the case may be. Anything in this Section (f) to the contrary
               notwithstanding, the Company shall be entitled, but shall not be
               required, to make such changes in the Exercise Price, in addition
               to those required



                                       8

<PAGE>   9

               by this Section (f), as it shall determine, in its sole
               discretion, to be advisable in order that any dividend or
               distribution in shares of Common Stock, or any subdivision,
               reclassification or combination of Common Stock, hereafter made
               by the Company shall not result in any Federal income tax
               liability to the holders of Common Stock or securities
               convertible into Common Stock (including Warrants).

                      (10) Whenever the Exercise Price is adjusted, as herein
               provided, the Company shall promptly but no later than 10 days
               after any request for such an adjustment by the Holder, cause a
               notice setting forth the adjusted Exercise Price and adjusted
               number of Warrant Shares issuable upon exercise of each Warrant,
               and, if requested, information describing the transactions giving
               rise to such adjustments, to be mailed to the Holders at their
               last addresses appearing in the Warrant Register, and shall cause
               a certified copy thereof to be mailed to its transfer agent, if
               any. In the event the Company does not provide the Holder with
               such notice and information within 10 days of a request by the
               Holder, then notwithstanding the provisions of this Section (f),
               the Exercise Price shall be immediately adjusted to equal the
               lowest Offering Price, Subscription Price or Conversion Price, as
               applicable, since the date of this Warrant, and the number of
               shares issuable upon exercise of this Warrant shall be adjusted
               accordingly. The Company may retain a firm of independent
               certified public accountants selected by the Board of Directors
               (who may be the regular accountants employed by the Company) to
               make any computation required by this Section (f), and a
               certificate signed by such firm shall be conclusive evidence of
               the correctness of such adjustment.

                      (11) In the event that at any time, as a result of an
               adjustment made pursuant to Subsection (1) above, the Holder of
               this Warrant thereafter shall become entitled to receive any
               shares of the Company, other than Common Stock, thereafter the
               number of such other shares so receivable upon exercise of this
               Warrant shall be subject to adjustment from time to time in a
               manner and on terms as nearly equivalent as practicable to the
               provisions with respect to the Common Stock contained in
               Subsections (1) to (9), inclusive above.

                      (12) Irrespective of any adjustments in the Exercise Price
               or the number or kind of shares purchasable upon exercise of this
               Warrant, Warrants theretofore or thereafter issued may continue
               to express the same price and number and kind of shares as are
               stated in the similar Warrants initially issuable pursuant to
               this Agreement.

               (g) OFFICER'S CERTIFICATE. Whenever the Exercise Price shall be
adjusted as required by the provisions of the foregoing Section, the Company
shall forthwith file in the custody of its Secretary or an Assistant Secretary
at its principal office and with its stock



                                       9

<PAGE>   10

transfer agent, if any, an officer's certificate showing the adjusted Exercise
Price determined as herein provided, setting forth in reasonable detail the
facts requiring such adjustment, including a statement of the number of
additional shares of Common Stock, if any, and such other facts as shall be
necessary to show the reason for and the manner of computing such adjustment.
Each such officer's certificate shall be made available at all reasonable times
for inspection by the holder or any holder of a Warrant executed and delivered
pursuant to Section (a) and the Company shall, forthwith after each such
adjustment, mail a copy by certified mail of such certificate to the Holder or
any such holder.

               (h) NOTICES TO WARRANT HOLDERS. So long as this Warrant shall be
outstanding, (i) if the Company shall pay any dividend or make any distribution
upon the Common Stock or (ii) if the Company shall offer to the holders of
Common Stock for subscription or purchase by them any share of any class or any
other rights or (iii) if any capital reorganization of the Company,
reclassification of the capital stock of the Company, consolidation or merger of
the Company with or into another corporation, sale, lease or transfer of all or
substantially all of the property and assets of the Company to another
corporation, or voluntary or involuntary dissolution, liquidation or winding up
of the Company shall be effected, then in any such case, the Company shall cause
to be mailed by certified mail to the Holder, at least fifteen days prior the
date specified in (x) or (y) below, as the case may be, a notice containing a
brief description of the proposed action and stating the date on which (x) a
record is to be taken for the purpose of such dividend, distribution or rights,
or (y) such reclassification, reorganization, consolidation, merger, conveyance,
lease, dissolution, liquidation or winding up is to take place and the date, if
any is to be fixed, as of which the holders of Common Stock or other securities
shall receive cash or other property deliverable upon such reclassification,
reorganization, consolidation, merger, conveyance, dissolution, liquidation or
winding up.

               (i) RECLASSIFICATION, REORGANIZATION OR MERGER. In case of any
reclassification, capital reorganization or other change of outstanding shares
of Common Stock of the Company, or in case of any consolidation or merger of the
Company with or into another corporation (other than a merger with a subsidiary
in which merger the Company is the continuing corporation and which does not
result in any reclassification, capital reorganization or other change of
outstanding shares of Common Stock of the class issuable upon exercise of this
Warrant) or in case of any sale, lease or conveyance to another corporation of
the property of the Company as an entirety, the Company shall, as a condition
precedent to such transaction, cause effective provisions to be made so that the
Holder shall have the right thereafter by exercising this Warrant at any time
prior to the expiration of the Warrant, to purchase the kind and amount of
shares of stock and other securities and property receivable upon such
reclassification, capital 



                                       10

<PAGE>   11

reorganization and other change, consolidation, merger, sale or conveyance by a
holder of the number of shares of Common Stock which might have been purchased
upon exercise of this Warrant immediately prior to such reclassification,
change, consolidation, merger, sale or conveyance. Any such provision shall
include provision for adjustments which shall be as nearly equivalent as may be
practicable to the adjustments provided for in this Warrant. The foregoing
provisions of this Section (i) shall similarly apply to successive
reclassifications, capital reorganizations and changes of shares of Common Stock
and to successive consolidations, mergers, sales or conveyances. In the event
that in connection with any such capital reorganization or reclassification,
consolidation, merger, sale or conveyance, additional shares of Common Stock
shall be issued in exchange, conversion, substitution or payment, in whole or in
part, for a security of the Company other than Common Stock, any such issue
shall be treated as an issue of Common Stock covered by the provisions of
Subsection (1) of Section (f) hereof.

               (j)    REGISTRATION UNDER THE SECURITIES ACT OF 1933.

                      (1) The Company shall advise the Holder of this Warrant or
               of the Warrant Shares or any then holder of Warrants or Warrant
               Shares (such persons being collectively referred to herein as
               "holders") by written notice at least four weeks (except, in the
               case of the proposed registration statements relating to (i) the
               shares of Common Stock issuable upon conversion of the Series A
               Convertible Preferred Stock issued in the exchange offer by the
               Company in February 1998, and (ii) the shares of Common Stock
               issued in the Units sold by the Company in the Private Placement
               and the shares of Common Stock underlying Warrants included in
               such Units, five days) prior to the filing of any registration
               statement or post-effective amendment thereto under the
               Securities Act of 1933 (the "Act") covering securities of the
               Company and will for a period of five years, commencing on the
               initial closing of the Private Placement, upon the request of any
               such holder, include in any such registration statement such
               information as may be required to permit a public offering of the
               Warrant Shares. The Company shall supply prospectuses and other
               documents as the Holder may request in order to facilitate the
               public sale or other disposition of the Warrant Shares, qualify
               the Warrant Shares for sale in such states as any such holder
               designates and do any and all other acts and things which may be
               necessary or desirable to enable such Holders to consummate the
               public sale or other disposition of the Warrant Shares, and
               furnish indemnification in the manner as set forth in Subsection
               (3)(C) of this Section (j). Such holders shall furnish
               information and indemnification as set forth in Subsection (3)(C)
               of this Section (j), except that the maximum amount which may be
               recovered from the Holder shall be limited to the amount of
               proceeds received by the Holder from the sale of the Warrant
               Shares.

                      (2) If any majority holder (as defined in Subsection (4)
               of this Section (j) below) shall give notice to the Company at
               any time during the five year period commencing on the initial
               closing of the Private Placement to the effect that such holder
               contemplates (i) the transfer of all or any part of his or its
               Warrants and/or Warrant Shares, or (ii) the exercise and/or
               conversion of all or any part of his or its Warrants and the
               transfer of all or any part of the Warrants and/or Warrant Shares
               under such circumstances that a public offering (within the
               meaning of the Act) of Warrant Shares will be involved, and
               desires to register



                                       11

<PAGE>   12

               under the Act the Warrant Shares, then the Company shall, within
               three weeks after receipt of such notice, file a registration
               statement pursuant to the Act, to the end that the Warrant Shares
               may be sold under the Act as promptly as practicable thereafter
               and the Company will use its best efforts to cause such
               registration to become effective and continue to be effective
               (current) (including the taking of such steps as are necessary to
               obtain the removal of any stop order) until the holder has
               advised that all of the Warrant Shares have been sold; provided
               that such holder shall furnish the Company with appropriate
               information (relating to the intentions of such holders) in
               connection therewith as the Company shall reasonably request in
               writing. In the event the registration statement is not declared
               effective under the Act prior to March 23, 2005, the Company
               shall extend the expiration date of the Warrants to a date not
               less than 90 days after the effective date of such registration
               statement. The holder may, at its option, request the
               registration of the Warrant Shares in a registration statement
               made by the Company as contemplated by Subsection (1) of this
               Section (j) or in connection with a request made pursuant to
               Subsection (2) of this Section (j) prior to the acquisition of
               the Warrant Shares upon exercise of the Warrants and even though
               the holder has not given notice of exercise of the Warrants. If
               the Company determines to include securities to be sold by it in
               any registration statement originally requested pursuant to this
               Subsection (2) of this Section (j), such registration shall
               instead be deemed to have been a registration under Subsection
               (1) of this Section (j) and not under Subsection (2) of this
               Subsection (j). The holder may thereafter at its option, exercise
               the Warrants at any time or from time to time subsequent to the
               effectiveness under the Act of the registration statement in
               which the Warrant Shares were included. Any registration
               requested pursuant to this Section (j)(2) shall, if the Company
               is eligible to use Form S-3 (or any successor Form) under the
               Act, be effected on a Form S-3 Registration Statement.

                      (3) The following provision of this Section (j) shall also
               be applicable:

                             (A) Within ten days after receiving any such notice
                      pursuant to Subsection (2) of this Section (j), the
                      Company shall give notice to the other holders of Warrants
                      and Warrant Shares, advising that the Company is
                      proceeding with such registration statement and offering
                      to include therein Warrant Shares of such other holders,
                      provided that they shall furnish the Company with such
                      appropriate information (relating to the intentions of
                      such holders) in connection therewith as the Company shall
                      reasonably request in writing. Following the effective
                      date of such registration, the Company shall upon the
                      request of any owner of Warrant Shares forthwith supply
                      such a number of prospectuses meeting the requirements of
                      the Act, as shall be requested by such owner to permit
                      such holder to make a public offering of all Warrant
                      Shares from time to



                                       12

<PAGE>   13

                      time offered or sold to such holder, provided that such
                      holder shall from time to time furnish the Company with
                      such appropriate information (relating to the intentions
                      of such holder) in connection therewith as the Company
                      shall request in writing. The Company shall also use its
                      best efforts to qualify the Warrant Shares for sale in
                      such states as such majority holder shall designate.

                             (B) The Company shall bear the entire cost and
                      expense of any registration of securities initiated by it
                      under Subsection (1) of this Section (j) notwithstanding
                      that Warrant Shares subject to this Warrant may be
                      included in any such registration. The Company shall also
                      comply with one request for registration made by the
                      majority holder pursuant to Subsection (2) of this Section
                      (j) at its own expense and without charge to any holder of
                      any Warrants and/or Warrant Shares; and the Company shall
                      comply with one additional request made by the majority
                      holder pursuant to Subsection (2) of this Section (j) (and
                      not deemed to be pursuant to Subsection (1) of this
                      Section (j)) at the sole expense of such majority holder.
                      Any holder whose Warrant Shares are included in any such
                      registration statement pursuant to this Section (j) shall,
                      however, bear the fees of his own counsel and any
                      registration fees, transfer taxes or underwriting
                      discounts or commissions applicable to the Warrant Shares
                      sold by him pursuant thereto.

                             (C) The Company shall indemnify and hold harmless
                      each such holder and each underwriter, within the meaning
                      of the Act, who may purchase from or sell for any such
                      holder any Warrants and/or Warrant Shares from and against
                      any and all losses, claims, damages and liabilities caused
                      by any untrue statement or alleged untrue statement of a
                      material fact contained in any registration statement
                      under the Act or any prospectus included therein required
                      to be filed or furnished by reason of this Section (j) or
                      caused by any omission or alleged omission to state
                      therein a material fact required to be stated therein or
                      necessary to make the statements therein not misleading,
                      except insofar as such losses, claims, damages or
                      liabilities are caused by any such untrue statement or
                      alleged untrue statement or omission or alleged omission
                      based uponinformation furnished or required to be
                      furnished in writing to the Company by such holder or
                      underwriter expressly for use therein, which
                      indemnification shall include each person, if any, who
                      controls any such underwriter within the meaning of such
                      Act provided, however, that the Company will not be liable
                      in any such case to the extent that any such loss, claim,
                      damage or liability arises out of or is based upon an
                      untrue statement or alleged untrue statement or omission
                      or alleged omission made in said registration statement,
                      said preliminary prospectus, said final



                                       13

<PAGE>   14

                      prospectus or said amendment or supplement in reliance
                      upon and in conformity with written information furnished
                      by such Holder or any other Holder, specifically for use
                      in the preparation thereof.

                             (D) Neither the giving of any notice by any such
                      majority holder nor the making of any request for
                      prospectuses shall impose such majority holder or owner
                      making such request any obligation to sell any Warrants
                      and/or Warrant Shares, or exercise any Warrants.

                      (4) The term "majority holder" as used in this Section (j)
               shall include any owner or combination of owners of Warrants or
               Warrant Shares in any combination if the holdings of the
               aggregate amount of:

                             (i) the Warrants held by him or among them, plus
                             (ii) the Warrants which he or they would be holding
                      if the Warrants for the Warrant Shares owned by him or
                      among them had not been exercised,

               would constitute a majority of the Warrants originally issued.

               The Company's agreements with respect to Warrants or Warrant
Shares in this Section (j) shall continue in effect regardless of the exercise
and surrender of this Warrant.

                                       ACCUMED INTERNATIONAL, INC.


                                       By  \S\ PAUL F. LAVALLEE
                                          ------------------------------
[SEAL]                                     Paul F. Lavallee,
                                           Chief Executive Officer and President

Dated:  March 23, 1998

Attest:

/s/ JOYCE WALLACH
------------------------
Joyce Wallach, Secretary


                                  PURCHASE FORM


                                                          Dated ____________, 19



<PAGE>   15

               The undersigned hereby irrevocably elects to exercise the within
Warrant to the extent of purchasing _______ shares of Common Stock and hereby
makes payment of _______ in payment of the actual exercise price thereof.

                                ________________

                     INSTRUCTIONS FOR REGISTRATION OF STOCK

Name ________________________________________
(Please typewrite or print in block letters)


Address _____________________________________


Signature ___________________________________



<PAGE>   16



                                 ASSIGNMENT FORM

               FOR VALUE RECEIVED, ______________ hereby sells, assigns and
transfers unto


Name _______________________________________
(Please typewrite or print in block letters)


Address ____________________________________

the right to purchase Common Stock represented by this Warrant to the extent of
______ shares as to which such right is exercisable and does hereby irrevocably
constitute and appoint ___________ as attorney, to transfer the same on the
books of the Company with full power of substitution in the premises.

Date ____________, 19__

Signature __________________________________