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                                                                   EXHIBIT 2.2

$265,000                                                Minneapolis, Minnesota

                                                                 June 30, 1999

                                 PROMISSORY NOTE

         FOR VALUE RECEIVED, the undersigned (collectively, the "Makers"),
jointly and severally, hereby promise to pay to the order of OXBORO MEDICAL
INTERNATIONAL, INC., a Minnesota corporation (the "Payee") at 13828 Lincoln
Street N.E., Ham Lake, Minnesota 55304, or at such other place as the holder
hereof may designate in writing from time to time, the principal sum of TWO
HUNDRED SIXTY-FIVE THOUSAND DOLLARS ($265,000), together with interest on the
unpaid principal balance from the date hereof at the rate of nine percent
(9%) per annum. All principal and accrued interest due hereon shall be due
and payable on September 30, 1999. The Makers shall have the right to prepay
all amounts due hereunder at any time without penalty. All payments made
hereon shall be applied first to interest, then to principal

         Notwithstanding the foregoing, this Note is subject to the Makers'
right of setoff as provided in Section 9(b) of the Agreement for Purchase and
Sale of Stock of even date herewith, by and among the Makers and the Payee
and the Makers and the Payee agree that such provisions are incorporated
herein and are binding upon the parties hereto.

         The Makers agree that upon the occurrence of any one or more of the
following events, all principal and interest due on this Note shall become
immediately due and payable at the option of the Payee, without notice:

         1.   The Makers fail to pay any amount hereunder when due;

         2.   A Maker: (i) commits an act of bankruptcy under the provisions of
              any state insolvency law or under the provisions of the Federal
              Bankruptcy Act; or (ii) initiates or has initiated against him,
              voluntarily or involuntarily, any action, process or proceeding
              under any insolvency law or other statute or law providing for
              the modification or adjustment of the rights of creditors; or

         3.   A Maker admits, in writing, of his inability to pay his debts as
              they become due.

         The Makers shall also be liable for all costs of collection incurred
in connection with this Note, including attorneys' fees. A waiver by the
holder hereof of a breach of the payment provisions hereof shall not operate
as, or be construed to be, a waiver of a subsequent breach of any such
provisions. The Makers hereby waive presentment, demand for payment, notice
of dishonor, notice of protest, protest, and all other notices or demands in
connection with the delivery, acceptance or performance of, or default under,
this Note. This Note shall be
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governed by and construed in accordance with the internal laws of the State
of Minnesota, without giving effect to the conflict of laws principles of
such state.

         IN WITNESS WHEREOF, the undersigned have executed this Note,
intending to be legally bound thereby, as of the above date.

THE PAYEE:                                          THE MAKERS:


OXBORO MEDICAL INTERNATIONAL, INC.                  JOHN MCGUIRE

By: /S/ MATTHEW E. BELLIN                           /S/ JOHN MCGUIRE
    Its: PRESIDENT AND CHIEF EXECUTIVE OFFICER      --------------------
                                                    John McGuire


                                                    STEPHEN KAMINSKI

                                                    /S/ STEPHEN KAMINSKI
                                                    --------------------
                                                    Stephen Kaminski


                                                    CHARLES KRUSE

                                                    /S/ CHARLES KRUSE
                                                    --------------------
                                                    Charles Kruse