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                                                                   EXHIBIT 10.28


                  AMENDMENT NUMBER ONE TO AMENDED AND RESTATED

              GENERAL PARTNERSHIP AGREEMENT OF CHILDRENS HEMOPHILIA
                       SERVICES AND RESTRICTIVE AGREEMENT

         This Agreement is made by and between HEMOPHILIA HEALTH SERVICES, INC.,
formerly known as HORIZON HEALTH SYSTEMS, INC. ("HHS"), CHILDRENS HOME CARE,
INC. ("CHC"), and CHILDRENS HEMOPHILIA SERVICES, a California general
partnership ("Partnership"), this 5th day of January, 2000.

                               W I T N E S S E T H

         WHEREAS, HHS and CHC have formed the partnership known as Childrens
Hemophilia Services, said partnership being evidenced by that written Amended
and Restated General Partnership Agreement of Childrens Hemophilia Services
dated November 10, 1998 ("Partnership Agreement"), and

         WHEREAS, CHC, HHS and Partnership have entered into a Restrictive
Agreement dated November 10, 1998 ("Restrictive Agreement"), and

         WHEREAS, HHS and CHC now desire to make certain changes and amendments
to the Partnership Agreement and Restrictive Agreement as set out herein.

         NOW THEREFORE, for and in exchange of the mutual promises contained
herein and for other good and valuable consideration, the receipt and adequacy
of which is hereby acknowledged, the parties hereto agree as follows:

         1. Section 13.2 of the Partnership Agreement is amended by deleting
same in its entirety and substituting in the place thereof the following Section
13.2:

                  (a) Each Partner and its Affiliates agree that, during the
                  term of this Agreement, it shall not compete with the
                  Partnership by providing any therapies, services, supplies or
                  goods which are being provided by the Partnership and
                  encompassed within the definition of the "Business" of the
                  Partnership as contained in this Agreement to any pediatric
                  patient whose Caregiver is Childrens Hospital of Los Angeles
                  or Childrens Hospital of Los Angeles Medical Group
                  ("Restricted Patient"). From time to time, either Partner may,
                  but shall have no obligation to, refer nonrestricted Patients
                  to the Partnership. Notwithstanding the forgoing, the resale
                  by CHC of drugs acquired in wholesale transactions with the
                  Partnership or HHS, shall not constitute a breach of this
                  agreement not to compete.

                  (b) For purposes of this Section 13.2, "Caregiver" shall mean
                  the provider of healthcare at which, or from whom, the patient
                  is, at the time of any determination made pursuant to the
                  provisions of this Section 13.2, receiving care, as either an
                  out-patient or in-patient, for the condition or illness which
                  necessitates the use of goods or services offered by the
                  Partnership.

                  (c) No Partner shall be in violation of this Section 13.2 if
                  it has made reasonable inquiry of the patient and the patient
                  has denied having a Caregiver which would cause the patient to
                  be covered by these restrictions. However, if the correct
                  information is subsequently discovered such that the patient
                  should not have been provided therapies, services, supplies or



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                  goods by the Partner, then the Partner shall so advise the
                  patient and shall use all reasonable efforts to encourage the
                  patient to have such therapies, services, supplies or goods,
                  as the case may be, provided by the Partnership, consistent
                  with the right of the patient to select his/her own healthcare
                  provider.

                  (d) HHS shall provide CHC a Monthly Referral Report
                  identifying all new patients started by HHS within a 100 mile
                  radius of Childrens Hospital Los Angeles by the 20th of the
                  following month. The Monthly Referral Report will include
                  physician, therapy, institution and a patient identifier. If a
                  patient is identified by the referring physician as a
                  Partnership patient, the Partner will make its best efforts to
                  transition the patient to the Partnership. All future
                  referrals from this referring physician will be directed to
                  the Partnership

                  (e) HHS shall prepare a Monthly Discharge Report indicating
                  all patients who have terminated service with the Partnership
                  by the 20th of the following month. The Monthly Discharge
                  Report shall include patient name, date of discharge, reason
                  for discharge and new vendor.

         2. Section 3 of the Restrictive Agreement be and hereby is amended by
deleting the last sentence thereof and substituting in the place thereof the
following:

                  Therefore, in consideration of the benefits conveyed
                  hereunder, and the purchase by HHS of the interest in
                  Partnership, for the Restricted Period and in the Restricted
                  Area, Restricted Party shall not, directly or indirectly,
                  jointly or individually, on its own behalf or as an agent,
                  employee, owner, partner, joint venturer, shareholder,
                  independent contractor, investor, consultant, employer or
                  advisor, engage in, assist other in engaging in, or establish
                  or own any interest in, any business, trade or occupations
                  engaging in the sale, marketing, distribution, promotion,
                  provision and distribution of clotting factor and such other
                  pharmaceuticals manufactured by third parties that were sold
                  by Partnership during the time that CHC was a partner in the
                  Partnership, whether or not such drugs are provided in the
                  hospital, home or other medical facilities.

         3. This Amendment is effective January 1, 2000. Except as otherwise
amended, the Restrictive Agreement and the Partnership Agreement shall remain in
full force and effect.

                                    HEMOPHILIA HEALTH SERVICES, INC.

                                    By: /s/ Thomas W. Bell, Jr.
                                        ------------------------------------

                                    Title: Senior Vice President
                                        ------------------------------------

                                    CHILDRENS HOME CARE, INC.

                                    By: /s/ Thomas J. McNulty
                                        ------------------------------------

                                    Title: President
                                        ------------------------------------



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                                    CHILDRENS HEMOPHILIA SERVICES, a
                                    general partnership

                                    By: Childrens Home Care, Inc., a
                                        general partner

                                    By: /s/ Thomas J. McNulty
                                        ------------------------------------

                                    Title: President
                                        ------------------------------------



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