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                                                                   EXHIBIT 10.23


                              MESA GENERAL HOSPITAL
                           AMENDMENT TO HOSPITAL LEASE

         THIS AMENDMENT TO HOSPITAL LEASE (hereinafter, "Amendment") is made and
entered into as of this 31st day of October, 2000 by and between Sierra
Equities, Inc. a California corporation (hereinafter, "Landlord") and Mesa
General Hospital, L.P., a Delaware limited partnership (hereinafter, "Tenant")
based upon the following facts:

         A. This Amendment is executed as a condition of, and concurrently with,
a Settlement and Release Agreement (hereinafter, "Settlement and Release") of
even date herewith by and among the Landlord, Tenant and Mesa General Hospital,
Inc. (hereinafter the "Former Tenant") and all of their respective Affiliates.

         B. Pursuant to the Settlement and Release, the parties hereto have
agreed upon the text of that certain Lease dated July 29, 1977 (hereinafter,
"Lease") between Landlord and the Former Tenant respecting promises with street
address of 515 North Mesa Drive, Mesa, Arizona as amended by the Addendum to
Lease (hereinafter, "Addendum"), executed August 11, 1983 and the Conforming
Amendment (hereinafter "Conforming Amendment"), dated June 10, 1991
(hereinbefore and hereinafter, collectively referred to as the "Hospital
Lease").

         C. Pursuant to the Settlement and Release and to an Assignment,
Assumption and Landlord Consent to Hospital Lease executed concurrent therewith,
the Hospital Lease has been assigned on a non-recourse basis respecting the
Former Tenant to the Tenant.

         NOW, THEREFORE, the LLC and Tenant agree to further amend the Hospital
Lease as follows:

         1.       PARAGRAPH II.A. RENT ADJUSTMENTS of the Addendum is amended to
                  by deleting the existing test of the Addendum.

         2.       PARAGRAPH 4. RENT (b) of the Lease is amended by deleting the
                  existing text of the Lease.

         3.       PARAGRAPH II.B. PERIODIC REAPPRAISALS of the Addendum is
                  amended by deleting the existing text.

         4.       PARAGRAPH II.D. FIXED RENT of the Addendum is modified by
                  deleting the sum of $87,695.00 and inserting the sum of
                  $118,668.00 in lieu thereof.

         5.       Recitals A.2, A.3, A.4 of the Conforming Amendment are
                  deleted.



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         IN WITNESS WHEREOF, Landlord and Tenant have executed this Amendment as
of the date and year first written above.

Landlord:                                      Tenant:

SIERRA EQUITIES, INC.                          MESA GENERAL HOSPITAL, L.P.
  a California corporation                       a Delaware limited partnership



By:      /s/ JAMES R. GEARY                   By:
     ------------------------------              -------------------------------
         James R. Geary                          Frank A. Coyle
         Chief Financial Officer                 Secretary


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         IN WITNESS WHEREOF, Landlord and Tenant have executed this Amendment as
of the date and year first written above.

Landlord:                                                     Tenant:

SIERRA EQUITIES, INC.                     MESA GENERAL HOSPITAL, L.P.
  a California corporation                  a Delaware limited partnership



By:                                       By: /s/ ALAN CHAPMAN
     -----------------------------            ---------------------------------
         James R. Geary                       Alan Chapman
         Chief Financial Officer              Division CFO











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