<PAGE>
Exhibit 7
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JOINT FILING AGREEMENT
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In accordance with Rule 13d-1(k) promulgated under the Securities Exchange
Act of 1934, as amended, the persons names below agree to the joint filing on
behalf of each of them a Statement on Schedule 13D (including amendments
thereto) with regard to the common stock of Novitron International, Inc., and
further agree that this Joint Filing Agreement be included as an Exhibit to such
joint filings. In evidence thereof, the undersigned, being duly authorized,
hereby execute this agreement as of the 8th day of January, 2001.
Date: January 8, 2001 /s/ Randal J. Kirk
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Randal J. Kirk
Date: January 8, 2001 CLINICAL CHEMISTRY HOLDINGS, INC.
By: /s/ Audrey Ho Ping Ting
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Audrey Ho Ping Ting
President and Chief Executive Officer
Date: January 8, 2001 RKJ, L.L.C.
By: /s/ Randal J. Kirk
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Randal J. Kirk
Manager
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