Exhibit 1 Agreement of Joint Filing Pursuant to Rule 13d-1(k)(1)(iii) of Regulation 13D-G of the General Rules and Regulations of the Securities and Exchange Commission under the Securities Exchange Act of 1934, as amended, the undersigned agree that...

                                                                       Exhibit 1

                           Agreement of Joint Filing

          Pursuant to Rule 13d-1(k)(1)(iii) of Regulation 13D-G of the General
Rules and Regulations of the Securities and Exchange Commission under the
Securities Exchange Act of 1934, as amended, the undersigned agree that the
statement to which this exhibit is attached is filed on behalf of each of them
in the capacities set forth below.

Date: July 26, 1999                   XXXXX & NEPHEW PLC


                                      By: /s/ Xxxxxxx Xxxxxx
                                          ---------------------------
                                      Name: Xxxxxxx Xxxxxx
                                            -------------------------
                                      Title: Company Secretary
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                                      XXXXX & NEPHEW HOLDINGS, INC.


                                      By: /s/ Xxxxxxxx X. Xxxxx
                                          ------------------------
                                      Name: Xxxxxxxx X. Xxxxx
                                            ----------------------
                                      Title: Chairman of the Board and President
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