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                                                                    Exhibit 3.43


                         CERTIFICATE OF INCORPORATION

                                      OF

                            EVEREST THREE IPA, INC.

              (UNDER SECTION 402 OF THE BUSINESS CORPORATION LAW)

     FIRST:    The name of the corporation is Everest Three IPA, Inc.

     SECOND:   The corporation is formed for the following purposes:

               a.    To function as an Independent Practice Association as
defined in 10 NYCRR 98.2(aa).

               b.    To arrange by contract for the delivery or provision of
health services by individuals, entities and facilities licensed or certified to
practice medicine and other health professions, and, as appropriate, ancillary
medical services and equipment, by which arrangements such health care providers
and suppliers will provide their services in accordance with and for such
compensation as may be established by a contract between the corporation and one
or more health maintenance organizations which have been granted a certificate
of authority pursuant to the provisions of Article 44 of the Public Health Law
of the State of New York, as amended.

               c.    To exercise the general powers and purposes authorized by
Section 202 of the Business Corporation Law which are to be exercised only as
powers and purposes incidental to accomplishing the primary Independent Practice
Association powers and purposes of the corporation.

               d.    Notwithstanding any other provision of this certificate to
the contrary, nothing contained herein shall authorize the corporation to
establish, operate, construct, lease or maintain a hospital or to provide
hospital service or health related service or to operate a drug maintenance
program, a certified home health agency, a hospice, or a health maintenance
organization or to provide a comprehensive health services plan as defined and
covered by Articles 28, 33, 36, 40 and 44, respectively of the Public Health
Law, or to solicit, collect or otherwise raise or obtain any funds,
contributions or grants from any source for the establishment or operation of
any hospital.

     THIRD:    The office of this corporation is to be located in the County of
Bronx, State of New York.
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     FOURTH:   The aggregate number of shares which this corporation shall have
authority to issue is 200 common shares, which shares are without par value.

     FIFTH:    The Secretary of the State of New York is hereby designated the
agent of this corporation upon whom process against this corporation may be
served. The post office address to which the Secretary of State shall mail a
copy of any process against this corporation served upon him as agent of this
corporation is Everest Healthcare Services, 1325 Morris Park Ave., Bronx, New
York 10461.

     SIXTH:    The duration of the corporation is to be perpetual.

     SEVENTH:  The corporation shall, to the fullest extent permitted by Article
7 of the Business Corporation Law, as the same may be amended and supplemented,
indemnify any and all persons whom it shall have power to indemnify under said
Article from and against any and all of the expenses, liabilities, or other
matters referred to in or covered by said Article, and the indemnification
provided herein shall not be deemed exclusive or any other rights to which any
person may be entitled under any By-Law, resolution of directors or
shareholder's resolution, agreement, or otherwise, as permitted by said Article,
as to action in any capacity in which such person served at the request of the
corporation.

     EIGHTH:   The personal liability of the directors of the corporation is
eliminated to the fullest extent permitted by the provisions of paragraph (b) of
Section 402 of the Business Corporation Law, as the same may be amended and
supplemented.

Signed on July 24, 1997


                                       /s/ E. Raymond Kolarsey
                                       --------------------------------------
                                       E. Raymond Kolarsey, Incorporator
                                       Hinman, Straub, Pigors & Manning, P.C.
                                       121 State Street
                                       Albany, New York 12207-1693