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                                                                    EXHIBIT 10.1

[SIERRA LAND GROUP, INC. LOGO]


                                                          801 NORTH BRAND BLVD.,
                                                                     SUITE 1010,
                                                 GLENDALE, CALIFORNIA 91203-1243
                                                                  (818) 247-3681
                                                            FAX # (818) 247-4315


April 26, 2005

Mr. William Stokes
Iasis Healthcare
Dover Centre
113 Seaboard Lane, Suite A200
Franklin, TN 37067

Re: Mesa General Hospital-Lease
    Sierra Equities, Inc. (Lessor)
    Mesa General, L.P. (Lessee)

Dear Bill:

Enclosed is a copy of the Mesa General Hospital Lease amendment dated April
30, 2003. The amendment is here by modified to read:

         1.       Term. The term of the Lease is extended to July 31, 2008 on
                  the terms and conditions contained in the Lease as modified
                  hereby.

All other terms and conditions of the Lease and the amendments thereto remain
unchanged.


Very truly yours,


/s/ James R. Geary
-----------------------------
James R. Geary
Chief Financial Officer
Sierra Equities, Inc.

JRG:lk

Enclosures

Agreed and Accepted
Mesa General, L.P.

By  /s/ Frank A. Coyle                        5/6/2005
   ----------------------------               ---------------------
   Frank A. Coyle                             Date

Its  Secretary
   -----------------------------


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                          MESA GENERAL HOSPITAL - LEASE

                               Amendment to Lease

         This Amendment to Lease (the "Amendment") is made and entered into as
of the 30th day of April, 2003 by and between Sierra Equities, Inc., a
California corporation (the "Lessor") and Mesa General Hospital, L.P., a
Delaware limited partnership (the "Lessee") based upon the following facts:

         A.    Lessor and Lessee are parties to the following lease documents
               (collectively, the "Lease") relating to certain leased premises
               more particularly described therein (the "Premises"):

         1.    Lease dated July 29, 1977 between Sierra Equities, Inc., a
               California corporation, and Mesa General Hospital, Inc., an
               Arizona corporation;

         2.    Addendum to Lease dated August 11, 1983 between Sierra Equities,
               Inc., a California corporation, and Mesa General Hospital, Inc.,
               an Arizona corporation;

         3.    Conforming Amendment to Lease dated June 10, 1991 (the "June 10,
               1991 Amendment") between Sierra Equities, Inc., a California
               corporation, and Mesa General Hospital, Inc., an Arizona
               corporation;

         4.    Settlement and Release Agreement dated October 31, 2000, among,
               inter alia, Sierra Equities, Inc., a California corporation, Mesa
               General Hospital, Inc., an Arizona corporation, and Mesa General
               Hospital, L.P., a Delaware limited partnership.

         B.    Lessor and Lessee desire to amend the Lease on the terms and
               conditions set forth herein.

               Based on the foregoing, and for other good and valuable
consideration, the receipt and adequacy of which are hereby acknowledged, the
parties hereto agree as follows:

         1. Term. The term of the Lease is extended to July 31, 2006, on the
terms and conditions contained in the Lease as modified hereby.

         2. Deletions. Paragraph 2 of the June 10, 1991 Amendment is deleted in
its entirety and shall be of no further force and effect.

         3. Rent.


               (a) The monthly rent payable for the period from August 1, 2003
through July 31, 2005 (the "First Adjustment Period") shall be adjusted by
multiplying the rent payable for the month of July 2003, as theretofore
adjusted, by a fraction, the numerator of which shall be the CPI (as defined
below) published for the month of June 2003 and the denominator of which shall
be the CPI published for the month of June 2001; provided, however, that in no
event shall the monthly rent for the First Adjustment Period be less than 100%
of, or more than 110% of, the rent for the month of July, 2003.


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              (b) The monthly rent payable for the period August 1, 2005 through
July 31, 2006 (the "Second Adjustment Period") shall be adjusted by multiplying
the rent payable for the month of July 2005, as theretofore adjusted, by a
fraction, the numerator of which shall be the CPI published for the month of
June 2005 and the denominator of which shall be the CPI published for the month
of June 2003; provided, however, that in no event shall the monthly rent for the
Second Adjustment Period be less than 100% of, or more than 110% of, the rent
for the month of July, 2005.

              (c) "CPI" means the Consumer Price Index for All Urban Consumers,
All Items, U.S. City Average, utilizing the latest base year adopted for such
Index, as reported by the Bureau of Labor Statistics of the United States
Department of Labor or any successor agency; provided, however, that
notwithstanding anything to the contrary contained in this paragraph, the two
CPIs used in the foregoing calculations shall in all cases utilize the same base
year. If the CPI ceases to be published or if for any reason the foregoing
computation cannot be based upon such changes in the CPI, it shall be based upon
changes in another index to be selected by Lessor that enjoys general
recognition and acceptance as an indicator of changes in consumer prices.

         4. Except as provided in this Amendment, all of the terms and
provisions of the Lease remain unmodified and in full force and effect.

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

                LESSOR:                 Sierra Equities, Inc., a
                                        California Corporation

                                        By:  /s/ Don Freeberg
                                           ----------------------------------
                                        Its:  Pres.
                                            ---------------------------------

                LESSEE:                 IASIS Healthcare Holdings, Inc.
                                        as General Partner to

                                        Mesa General Hospital, L.P., a
                                        Delaware limited partnership

                                        By:  /s/ W. Carl Whitmer
                                           ----------------------------------
                                        Its: Chief Financial Officer
                                            ---------------------------------