EXHIBIT 6.1 LICENSE AMENDMENT AGREEMENT THIS AGREEMENT, dated February 3, 1997, and effective as of January 1, 1994, amends the License Agreement dated May, 1992 between Daltex Medical Sciences, Inc. ("Daltex"), a Delaware corporation having a place...

                                                                    EXHIBIT 6.1

                           LICENSE AMENDMENT AGREEMENT


                  THIS AGREEMENT, dated February 3, 1997, and effective as of
January 1, 1994, amends the License Agreement dated May, 1992 between Daltex
Medical Sciences, Inc. ("Daltex"), a Delaware corporation having a place of
business at 00 Xxxxxx Xxxx, Xxxxxxxxx, XX 00000 ("Licensor") and X.X. Xxxx &
Associates, Inc. ("Gore"), a Delaware corporation having a place of business at
0000 Xxxxx Xxxxxx Xxxxxx, Xxxxxxxxx, XX 00000 ("Licensee").

                  WHEREAS, Licensor and Licensee have previously entered into a
License Agreement dated May 1992 ("1992 License Agreement") relating to certain
technology set forth therein and which remains in full force and effect;

                  WHEREAS, Licensor and Licensee, to their mutual benefit,
desire to modify certain aspects of the 1992 License Agreement;

                  NOW, THEREFORE, in consideration of the above premises and the
mutual covenants and conditions hereinafter contained, and for other good and
valuable consideration, the receipt and sufficiency of which is acknowledged by
the execution and delivery hereof, the parties hereby covenant and agree as
follows:

                  Section 1.b is hereby amended to read:

                  "Licensed Products" shall mean any product, good, or item
within the Field (as defined below), produced in whole or in part, using a part
or all of the technology embodied in Licensed Patents, and made of, but not
limited to, Fluorinated Hydrocarbons (including, but not limited to, PTFE,
ePTFE, FEP, PFA, HFP and VF).

                  Schedule 1 is hereby amended to read:

                  Segment           Development Fee        Royalty Payment

         1.       Patches           $15,000.00/year        $8.00/per unit sold

               A. Soft Tissue: Includes Xxxx patch products used in the
following applications:

               i)   Reconstruction of hernias and soft tissue deficiencies, such
                    as abdominal wall defects, diaphragmatic hernia,
                    laparoscopic hernia, pelvic floor and lid reconstruction,
                    ventral hernia, laparoscopic inguinal hernia, muscle flap
                    reconstruction, vaginal prolapse, rectal prolapse, scrotal
                    hernia, gastric banding and temporary facial bridging; and

               ii)  Plastic and reconstructive surgery, such as malarplasty,
                    mentoplasty, rhinoplasty, maxilloplasty, frontal defects,
                    reconstructive lip augmentations, orbital repair, facial
                    folds, facial slings and auricuoplasty.


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               B. Cardiovascular: Includes Xxxx patch products used in
cardiovascular and cardiac patching, such as carotid patch, angioplasty,
profundaplasty, AV access graft patching, septal defects, outflow tracts,
aneurysm repair and other patch angioplasty.

               C. Surgical Membrane/Adhesion Limiting: Includes Xxxx patch
products used in the following applications:

               i)   Reconstruction or repair of the peritoneum, where minimal
                    adhesions to a prosthetic material are desired, such as
                    infertility surgery, gynecological surgery and gynecological
                    and surgical oncology;

               ii)  Temporary or permanent prosthesis for the repair of dura
                    mater during neurosurgery, such as tumor resection, tethered
                    cord releases, trauma repair and Chiari decompression;

               iii) Reconstruction of the pericardium where minimal adhesions
                    are desired; and

               iv)  Wrap for pedicled arterial conduits.

                  Segment           Development Fee        Royalty Payment

         2.       Vascular Grafts   $15,000.00/year        $9.00/per unit sold

               Includes Xxxx vascular graft products used as vascular protheses,
such a peripheral, dialysis, aortic, extra-anatomic, venous, aorto-pulmonary
shunts, subclavian-pulmonary shunts and innominate-pulmonary shunts.

                  Segment               Development Fee     Royalty Payment

         3.       Nonabsorbent Sutures   $15,000.00/year    $0.15/per unit sold

               Includes Xxxx suture products used for all types of soft tissue
approximation, such as cardiac, endovascular, peripheral vascular, vascular,
soft tissue repair, neurosurgery, plastic and reconstructive surgery,
gynecological, oncological and orthopedic.

         4.       For all products within Product and Market Application 
Segments not specifically listed above, but which are covered by the Licensed
Patents, the royalty rate shall be five (5%) percent of Xxxx'x selling price.

                   All other terms, conditions and provisions of the License
Agreement of May 1992 remain unchanged.

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                  IN WITNESS WHEREOF, Daltex and Xxxx have executed this License
Amendment Agreement as of the date set forth above.


ACCEPTED AND AGREED:

                                       DALTEX MEDICAL SCIENCES, INC.


Dated:  February 3, 1997           /s/ Xxxxx Xxxxxxx
                                       Xxxxx Xxxxxxx, President


                                       X.X. XXXX & ASSOCIATES, INC.


Dated:  February 3, 1997           /s/ Xxxxx Xxxxxxx
                                       Xxxxx Xxxxxxx




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