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                                                                   EXHIBIT 10.71

                                 SELFCARE, INC.

                         EXCHANGE AGREEMENT- CDIL NOTES




To:      Selfcare, Inc.
         200 Prospect Street
         Waltham, MA  02154

     You have advised the undersigned that Selfcare, Inc., (the "Company" or
"you") is offering to certain investors the opportunity to exchange principal
amounts outstanding on certain notes (the "Original Notes") for promissory notes
(the "Convertible Notes") which will be convertible (as more fully described
below) into shares of common stock, par value $.001 per share (the "Common
Stock"), of the Company. The Original Notes constitute those certain promissory
notes issued by the Company in 1995, in an aggregate principal amount of $3.0
million at an annual interest rate of 10%, to refinance certain debt incurred by
the Company to acquire Cambridge Diagnostics Ireland, Ltd. The amounts to be
exchanged for the Convertible Notes, if this Exchange Agreement is accepted by
the Company, consist of the principal currently outstanding on the Original
Notes which the undersigned understands is an aggregate of $2.975 million.
Accrued interest on the Original Notes will be paid by the Company to the
undersigned by check.

     The Convertible Notes will be issued in a principal amount equal to the
principal amount of the Original Note(s) exchanged by the undersigned, will bear
interest at the rate of ten percent (10%) per annum, will mature on the six
month anniversary of the date of issuance of the Convertible Notes (the
"Maturity Date"), will be convertible by the holder of such Convertible Notes in
whole at any time on or prior to the Maturity Date into that number of shares of
Common Stock determined by dividing the principal balance of such Convertible
Note plus any accrued interest thereon by the Conversion Price (as defined
below) and will automatically convert, without any action on the part of the
holder, on the Maturity Date into that number of shares of Common Stock
determined by dividing the principal balance of such Convertible Note plus the
accrued interest thereon by the Conversion Price. The "Conversion Price" for a
Convertible Note will be equal to the closing bid price of a share of Common
Stock, as quoted on the American Stock Exchange, on the day immediately
preceding the day of issuance of such Convertible Note multiplied by eighty-five
percent (85%). The undersigned acknowledges that the Convertible Notes and the
Common Stock are more fully described in the Information Package (as defined
below).

     Based on the foregoing and subject to the terms and conditions of this
Exchange Agreement (the "Exchange Agreement"), the undersigned agrees with you
as follows:






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     1. THE EXCHANGE.

     The undersigned hereby tenders this Exchange Agreement for the exchange
(the "Exchange") of the principal amount(s) currently due and outstanding (the
"Converted Balance") under the Original Note(s) held by the undersigned for a
Convertible Note issued in a principal amount equal to the Converted Balance.

     Upon acceptance of this Exchange Agreement by the Company, the undersigned
will promptly deliver the Note(s) held by the undersigned to the Company and the
Company will promptly issue the Convertible Note. The Company will also pay
accrued interest on the Original Note(s) held by the undersigned accrued through
the date of acceptance of this Exchange Agreement by check. The Convertible Note
issued to the undersigned will begin accruing interest on the date of acceptance
of this Exchange Agreement.

     2. INFORMATION.

     The undersigned acknowledges receipt of an information package (the
"Information Package") containing the following items:

          1.   A description of the Convertible Notes and the Common Stock, a
               summary of certain risk factors applicable to the Company and the
               securities proposed to be exchanged herefor, a discussion of
               certain recent developments and a discussion of the use of the
               proceeds (if any) from the offering contemplated hereby;

          2.   The Company's Annual Report on Form 10-KSB/A;

          3.   The Company's Proxy Statement for its most recent Annual Meeting
               of Stockholders;

          4.   The Company's Quarterly Reports on Form 10-QSB for the quarters
               ended March 31, 1997, June 30, 1997 and September 30, 1997;

          5.   The Company's Current Report on Form 8-K filed with the
               Securities and Exchange Commission (the "SEC") on March 5, 1997,
               as amended by the Form 8-K/A filed with the SEC on May 5, 1997;

          6.   The Company's Amended and Restated Certificate of Incorporation,
               as amended; and

          7.   The Company's Amended and Restated By-laws.




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     3. ACCEPTANCE OF EXCHANGE.

     It is understood and agreed that this Exchange Agreement is made subject to
the following terms and conditions:

          (a) The Company shall have the right to accept or reject this Exchange
Agreement, in whole or in part, for any reason, including the inability of the
undersigned to meet the standards imposed by Regulation D promulgated by the
Securities and Exchange Commission under the Securities Act, the ineligibility
of the undersigned to meet the standards imposed by applicable state or foreign
securities laws, or for any other reason, or for no reason. If this Exchange
Agreement is rejected, the Original Note(s) held by the undersigned will be
satisfied pursuant to the terms thereof.

          (b) Two copies of this Agreement are being executed by the
undersigned. If accepted, one copy of this Agreement will be retained by the
Company and one copy of this Agreement, after execution by the Company, shall be
delivered to the undersigned.

          4. WITHDRAWAL OF OFFERING OR EXCHANGE.

          (a) The Company reserves the right to withdraw this offering in whole
 or in part for any reason or for no reason.

          (b) If the offering is withdrawn by the Company, the undersigned will
be paid the amounts outstanding under the Original Note(s) held by the
undersigned pursuant to the term thereof and will have no liability to the
Company other than to return to the Company the Information Package and other
documents, if any, furnished to the undersigned by or on behalf of the Company
in connection with the offering, and the Company will have no further liability
to the undersigned with respect to the Exchange.

          5.REPRESENTATIONS AND WARRANTIES OF THE UNDERSIGNED.

          The undersigned hereby represents and warrants to the Company as
     follows:

            (a) all information provided and representations made by the
undersigned in the Prospective Investor Questionnaire (the "Questionnaire") of
the Company, a form of which Questionnaire is attached hereto as EXHIBIT A, are
true and correct in all respects as of the date hereof.

            (b) The address set forth at the foot of this Exchange Agreement is
the address of the undersigned's principal residence or place of business, and
the undersigned has no present intention of becoming a resident of any other
country, state or jurisdiction.




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            (c) Unless the undersigned shall have notified the Company to the
contrary in writing prior to or together with the tendering of this Exchange
Agreement, the undersigned acknowledges that the undersigned has not relied upon
the advice of a "Purchaser Representative" (as defined in the aforementioned
Regulation D) in evaluating the risks and merits of this investment.

            (d) The undersigned has received and read or reviewed and is
familiar with the Information Package (including the exhibits thereto) and the
undersigned confirms that all documents, records, and books pertaining to the
investment in the Company and requested by the undersigned have been made
available or delivered to the undersigned.

            (e) The undersigned has had an opportunity to ask questions of and
receive answers from the Company, or a person or persons acting on the Company's
behalf, concerning the terms and conditions of this investment.

            (f) The undersigned understands and acknowledges the following:

               (i) the securities for which the undersigned hereby subscribes
          (including any securities into which such securities may be converted)
          have not been registered under the Securities Act or under the
          securities laws of any state or other jurisdiction in reliance upon
          exemptions for private offerings;

               (ii) while the Company may in the future register such securities
          (or any securities into which such securities may be converted), it is
          under no obligation to do so, except as otherwise provided herein;

               (iii) such securities (including any securities into which such
          securities may be converted) cannot be resold unless registered under
          the Securities Act and any applicable securities law of any state or
          other jurisdiction, or an exemption from registration is available;

               (iv) as of the date hereof, there is no public market for such
          securities (including any securities into which such securities may be
          converted);

               (v) the undersigned is purchasing such securities without being
          furnished any offering literature or prospectus other than the
          Information Package, and is relying only on the information contained
          therein and herein in evaluating the risks and merits of this
          investment; and

               (vi) no person or entity has been authorized to give any
          information or make any representations in connection with this
          investment other than that contained in the Information Package.



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               (g) The securities for which the undersigned hereby subscribes
are being acquired solely for the undersigned's own account, for investment and
not with a view to or for the resale, distribution, subdivision, or
fractionalization thereof; the undersigned has no present plans to enter into
any contract, undertaking, agreement, or arrangement relating thereto.

               (h) The undersigned has such knowledge and experience that the
undersigned is capable of evaluating the matters set forth in the Information
Package and the risks and merits relating thereto.

               (i) The undersigned, if it is a corporation or other entity,
acknowledges that it, through the officer(s) and/or director(s) and/or other
employees responsible for making an investment decision with regard to the
Exchange, has such knowledge and experience in financial and business matters
that it is capable of evaluating the relative risks and merits of this
investment, and further acknowledges that the representations and warranties
contained in this Section 4 are true and accurate with respect to it.

               (j) The undersigned, if he, she or it is an officer, director or
greater than 10% stockholder of the Company, has not directly or indirectly sold
any shares of the Company's Common Stock during the preceding six month period
and, if this Exchange Agreement is accepted, understands that he, she or it may
not sell any such shares during the six month period following the Exchange
without possibly subjecting himself, herself or itself to liability under
Section 16 of the Securities Exchange Act of 1934, as amended.

     The foregoing representations and warranties are true and accurate as of
the date hereof and shall be true and accurate as of the date of acceptance of
this Exchange Agreement and delivery of the shares of Common Stock and shall
survive such delivery.

     6. TRANSFERABILITY; LEGEND.

     This Exchange Agreement, or any of the undersigned's interest herein, may
not be transferred or assigned and any assignment or transfer of the Convertible
Notes or the shares of Common Stock issuable upon conversion thereof shall be
made only in accordance with applicable securities laws. In addition, the
undersigned understands that the Convertible Notes and the certificate(s)
representing the shares of Common Stock issuable upon conversion thereof shall
bear the following restrictive legend:

         THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE
         SECURITIES ACT OF 1933, AS AMENDED (THE "ACT") OR ANY STATE SECURITIES
         OR BLUE SKY LAWS AND MAY NOT BE OFFERED, SOLD, TRANSFERRED,
         HYPOTHECATED OR OTHERWISE ASSIGNED EXCEPT (1) PURSUANT TO A
         REGISTRATION STATEMENT WITH RESPECT TO SUCH SECURITIES WHICH IS
         EFFECTIVE UNDER THE ACT OR (2)




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          PURSUANT TO AN AVAILABLE EXEMPTION FROM REGISTRATION UNDER THE ACT
          RELATING TO THE DISPOSITION OF SECURITIES AND (3) IN ACCORDANCE WITH
          APPLICABLE STATE SECURITIES AND BLUE SKY LAWS.

          7. REVOCATION.

          The undersigned agrees that the undersigned shall not cancel,
terminate or revoke this Exchange Agreement or any agreement of the undersigned
made hereunder, and that this Exchange Agreement shall survive the death or
disability of the undersigned.

          8. PAYMENTS TO U.S. BOSTON CAPITAL CORPORATION.

          U.S. Boston Capital Corporation, a broker-dealer ("U.S. Boston"), the
President of which is Willard Lee Umphrey, a director and principal stockholder
of the Company, will receive a fee of three percent (3%) of the principal amount
of all Notes exchanged in connection with the offering contemplated hereby.

          9. MISCELLANEOUS.

               (a) NO WAIVER; CUMULATIVE REMEDIES. No failure or delay on the
part of any party to this Exchange Agreement, in exercising any right, power or
remedy hereunder shall operate as a waiver thereof; nor shall any single or
partial exercise of any such right, power or remedy preclude any other or
further exercise thereof or the exercise of any other right, power or remedy
hereunder. The remedies herein provided are cumulative and not exclusive of any
remedies provided by law.

               (b) ADDRESSES FOR NOTICES, ETC. All notices requests, demands and
other communications provided for hereunder shall be in writing (including
telegraphic communication) and mailed, telecommunicated, telegraphed, telexed or
delivered:

     If to the Company, to the address set forth above, Telecopier: (781)
647-3939, Attention: Ron Zwanziger, or at such other address as shall be
designated by the Company in a written notice to the undersigned complying as to
delivery with the terms of this Section 8. A copy of all notices, demands and
other communications to the Company shall be sent to the offices of Goodwin,
Procter & Hoar LLP, Exchange Place, Boston, Massachusetts 02109, Attention:
Martin Carmichael III, P.C. and Stephen W. Carr, P.C.

     If to the undersigned, at its address as set forth on the signature page
hereof or at such other address as shall be designated by the undersigned in a
written notice to the Company complying as to delivery with the terms of this
Section 9.





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     All such notices, requests, demands and other communications shall, when
mailed, registered or certified mail, return receipt requested, postage prepaid,
telecommunicated, telegraphed or telexed, respectively, be effective when
deposited in the mails, confirmed received by telecommunication or delivered to
the telegraph or telex company, respectively, addressed as aforesaid.

          (c) SEVERABILITY. The invalidity or unenforceability of any provision
hereof shall in no way affect the validity or enforceability of any other
provision.

          (d) GOVERNING LAW. This Subscription shall be governed by, and
construed in accordance with, the laws of The Commonwealth of Massachusetts,
without regard to the choice of law principles thereunder.

                     [Remainder of Page Intentionally Blank]


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     IN WITNESS WHEREOF, the undersigned has executed this Exchange Agreement as
of this __ day of December, 1997.



---------------------------------               --------------------------------
Name of Investor (Please print)                 Signature of Investor
and Capacity in Which
Subscription is Made

Address of Investor:


---------------------------------               --------------------------------
Number         Street                           Signature of Co-Investor, if any


---------------------------------
City          State      Zip Code


---------------------------------
Country


Tel. No. (     )  _______________



---------------------------------
Social Security Number for
Individual or other Taxpayer
Identification Number


ACCEPTED BY:

SELFCARE, INC.


By:_______________________________________



NUMBER OF SHARES OF COMMON STOCK:_______________________



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                                    EXHIBIT A



                   NAME OF INVESTOR: ________________________



                       PROSPECTIVE INVESTOR QUESTIONNAIRE

                                 Selfcare, Inc.
                               200 Prospect Street
                                Waltham, MA 02154



     The securities of Selfcare, Inc. (the "Company") are being offered in
reliance on Regulation D under the Securities Act of 1933, as amended
("Regulation D"), and similar provisions of state law. To satisfy the
requirements of Regulation D and applicable state law, the Company must
determine whether a prospective investor (the "Investor") meets the Regulation D
and state law definitions of "accredited investor" before selling (or, in some
states, offering) securities to such person. This Questionnaire is designed to
assist the Company in making this determination.

     Please complete, execute and date this Prospective Investor Questionnaire
and deliver it along with an executed Exchange Agreement to the Company at the
address set forth above. Your answers will, at all times, be kept confidential
except as necessary to establish that the offering and sale of the securities
will not result in a violation of applicable law.

     1)   To establish the basis of the Investor's status as an accredited
          investor, please answer the questions set forth below.

          a)   Is the Investor an individual with a net worth (or net worth with
               his or her spouse) in excess of $1 million?

                  Yes ______                         No ______



                                      A-1


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          b)   Is the Investor an individual with net income (without including
               any net income of the Investor's spouse) in excess of $200,000,
               or joint income with the Investor's spouse in excess of $300,000,
               in each of the two most recent years, and does the Investor
               reasonably expect to reach the same income level in the current
               year?

                    Yes ______                     No ______


          c)   Is the Investor an employee benefit plan within the meaning of
               the Employee Retirement Income Security Act of 1974 (hereinafter
               "ERISA") whose decision to invest in the Company is being made by
               a plan fiduciary which is either a bank, savings and loan
               association, insurance company or registered investment adviser
               or, alternatively, does the employee benefit plan have total
               assets in excess of $5,000,000 or is the employee benefit plan
               "self-directed" with investment decisions made solely by
               person(s) who are accredited investors(s)?

                    Yes ______                     No ______


          d)   Is the Investor a plan established and maintained by a state, its
               political subdivisions, or any agency or instrumentality of a
               state or its political subdivisions for the benefit of its
               employees with total assets in excess of $5,000,000?

                    Yes ______                     No ______


          e)   Is the Investor a trust (including an individual retirement
               arrangement formed as a trust or a tax-qualified pension and
               profit sharing plan (E.G., a Keogh Plan) formed as a trust but
               not subject to ERISA) with total assets in excess of $5,000,000
               that was not formed for the specific purpose of acquiring
               securities of the Company and whose purchase is directed by a
               person with such knowledge and experience in financial and
               business matters that such person is capable of evaluating the
               merits and risks of the prospective investment?

                    Yes ______                     No ______


                                      A-2

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          f)   Is the Investor a corporation, partnership, Massachusetts or
               similar business trust or an organization described in Section
               501(c)(3) of the Internal Revenue Code that was not formed for
               the specific purpose of acquiring securities of the Company and
               whose total assets exceed $5,000,000?

                    Yes ______                     No ______


          g)   Is the Investor one of the following entities:

               (i)  A "bank" as defined in Section 3(a)(2) of the Securities Act
                    or any "savings and loan association" or other institution
                    as defined in Section 3(a)(5)(A) of the Securities Act
                    whether acting in an individual or fiduciary capacity;

               (ii) A "broker/dealer" registered pursuant to Section 15 of the
                    Securities Exchange Act of 1934;

               (iii) An "insurance company," as defined in Section 2(13) of the
                    Securities Act;

               (iv) An "investment company" registered under the Investment
                    Company Act of 1940 or a "business development company" as
                    defined in Section 2(a)(48) of the Investment Company Act of
                    1940;

               (v)  A "Small Business Investment Company" licensed by the U.S.
                    Small Business Administration under Section 301(c) or (d) of
                    the Small Business Investment Act of 1958; or

               (vi) A "Private Business Development Company" as defined in
                    Section 202(a)(22) of the Investment Advisers Act of 1940?

                    Yes ______                     No ______


          If yes, then which entity (i.e., (g)(i) through (vi) above)?


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



                                      A-3
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               h)   Is the Investor an entity (other than a trust but including
                    a grantor trust) in which all of the equity owners can
                    answer "Yes" to any one question set forth in Sections 1(a)
                    through 1(g) immediately above?

                             Yes ______                     No ______


               2)   Is the Investor acquiring securities of the Company as a
                    principal for the purpose of investment and not with a view
                    to resale or distribution?

                             Yes ______                     No ______


               3)   By signing this Questionnaire, the Investor hereby confirms
                    the following statements:

                    a)   The Investor shall immediately provide the Company with
                         corrected information in the event any information
                         given herein was untrue.

                    b)   The Investor acknowledges that any delivery to the
                         Investor of information relating to the Company, prior
                         to the determination by the Company of the suitability
                         of the Investor as an investor in the Company, shall
                         not constitute an offer of securities of the Company
                         until such determination of suitability shall be made.

                    c)   The answers of the Investor to the foregoing questions
                         are true and complete to the best of the information
                         and belief of the undersigned, and the Company shall be
                         notified promptly of any changes in the foregoing
                         answers.



---------------------------------        ------------------------------------
Signature of Investor                    Signature of Investor
(or duly authorized agent)               (or duly authorized agent)


---------------------------------        ------------------------------------
Title:                                   Title:

---------------------------------        ------------------------------------
Print Name Signed Above                  Print Name Signed Above



                                      A-4