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                                                                     Exhibit 3.6

                       CERTIFICATE OF OWNERSHIP AND MERGER

                                     MERGING

                      HEALTHCARE INTEGRATED SERVICES, INC.

                                      INTO

                        HEALTHCARE IMAGING SERVICES, INC.

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                         Pursuant to Section 253 of the
                General Corporation Law of the State of Delaware
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         Healthcare Imaging Services, Inc., a corporation organized and
           existing under the General Corporation Law of the State of
             Delaware (the "Corporation"), does hereby certify that:

         1. The Corporation owns all of the outstanding shares of HealthCare
Integrated Services, Inc., a Delaware corporation.

         2. The Corporation, by the following resolutions of its Board of
Directors, duly adopted by unanimous written consent pursuant to Section 141(f)
of the General Corporation Law of the State of Delaware (the "DGCL") on the 29th
day of July, 1999, determined to merge HealthCare Integrated Services, Inc. into
itself on the terms and conditions set forth in the following resolutions:

            WHEREAS, the Corporation owns all of the issued and outstanding
            shares of common stock, par value $.01 per share, of HealthCare
            Integrated Services, Inc. (the "Subsidiary"); and

                     WHEREAS, the Corporation wishes to merge the
            Subsidiary into itself (the "Merger") in accordance with
            Section 253 of the DGCL.

                     NOW THEREFORE, BE IT RESOLVED, that, effective August
            1, 1999, the Subsidiary be merged with and into the
            Corporation in accordance with Section 253 of the DGCL and
            that the Corporation be the surviving corporation in the
            Merger;

                     RESOLVED FURTHER, that, upon the effectiveness of the
            Merger, the Corporation shall assume all of the liabilities
            and obligations of the Subsidiary;

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                     RESOLVED FURTHER, that the proper officers of the
            Corporation be, and each of them hereby is, authorized,
            empowered and directed to execute and file, in accordance with
            Section 253 of the DGCL, a Certificate of Ownership and Merger
            with the Secretary of State of the State of Delaware that,
            among other things, sets forth a copy of these resolutions and
            the date of adoption thereof;

                     RESOLVED FURTHER, that, upon the effectiveness of the
            Merger, the name of the Corporation shall be changed to
            "HealthCare Integrated Services, Inc." and Article FIRST of
            the Certificate of Incorporation of the Corporation shall be
            amended in its entirety to read as follows:

                     "The name of the Corporation is HealthCare Integrated
            Services, Inc."

                              ; and

                     RESOLVED FURTHER, that the proper officers of the
            Corporation be, and each of them hereby is, authorized,
            directed and empowered to execute and deliver all such other
            documents or instruments necessary, appropriate or desirable
            for the implementation of the foregoing resolutions, and to do
            and perform such other acts and things as they or any of them
            determine, in their or his sole discretion, to be necessary,
            appropriate or desirable to carry out any of the foregoing
            resolutions, any such determination to be conclusively
            evidenced by the execution and delivery of any such document
            or instrument or the doing or performing of any such act or
            thing.

         IN WITNESS WHEREOF, the undersigned has executed this Certificate this
29th day of July, 1999.


                                            HEALTHCARE IMAGING SERVICES, INC.

                                            By:/s/ Elliott H. Vernon
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                                               Elliott H. Vernon
                                               Chairman, President and Chief
                                               Executive Officer

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