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                                                                   EXHIBIT 3.123

                            ARTICLES OF INCORPORATION

                                       OF

                         PETER G. KLACSMANN, M.D., P.C.

                                    ARTICLE I

     The name of the corporation is Peter G. Klacsmann, M.D., P.C.

                                   ARTICLE II

     The corporation shall have perpetual duration.

                                   ARTICLE III

     The purpose of the corporation is to practice medicine and pathology and
the general nature of the business to be transacted by this corporation is: (a)
To engage in every phase and aspect of the business of rendering the same
professional service to the public that a physician duly licensed under the laws
of the State of Georgia is authorized to render, but such professional services
shall be rendered only through officers, employees, and agents who are duly
licensed or otherwise legally authorized to practice medicine within this State;
(b) To own real and personal property necessary or appropriate for the rendering
of the professional services authorized by these Articles of Incorporation and
to invest the funds of this professional corporation in real estate, mortgages,
stocks, bonds, or any other type of investment

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whatsoever; (c) To do, either alone or in conjunction with other corporations,
associations, firms or individuals, all and everything necessary and proper for
the accomplishment of any of the purposes, the attainment of any of the objects,
or the furtherance of the purposes and objects enumerated in these Articles of
Incorporation or any amendment thereof, necessary or incidental to the
protection and benefit of this professional corporation; (d) The foregoing
enumeration of specific purposes or objects shall not be held to limit or
restrict in any manner the purposes or objects of this professional corporation
otherwise permitted by the laws of this State.

                                   ARTICLE IV

     This corporation hereby elects to be governed by the provisions of the
Georgia Professional Corporation Act, and the corporation and its shareholders
shall have all of the power and shall enjoy all of the rights, privileges and
immunities as provided for under the Georgia Business Corporation Code, except
as changed, restricted or enlarged by the provisions of said Georgia
Professional Corporation Act.

                                    ARTICLE V

     The total number of shares of stock which the corporation shall have
authority to issue is 1,000 with no par value.

                                       -2-
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                                   ARTICLE VI

     The corporation will not commence business until a minimum of Five Hundred
and No/100 Dollars ($500.00) has been received for the issuance of shares.

                                   ARTICLE VII

     The registered office of the corporation in the State of Georgia is to be
located at 3560 Pebble Beach Drive, Augusta, Georgia 30907. Its registered agent
at such address is Peter G. Klacsmann. His consent to serve is attached hereto.

                                  ARTICLE VIII

     The initial Board of Directors shall consist of two (2) members who shall
be:

                                      Peter G. Klacsmann
                                      3560 Pebble Beach Drive
                                      Augusta, Georgia 30907

                                      Karen Klacsmann
                                      3560 Pebble Beach Drive
                                      Augusta, Georgia 30907

                                   ARTICLE IX

     The corporation shall have and exercise all the powers conferred by the
laws of the State of Georgia upon professional corporations formed under the
laws of such State.

     Dated this 8 day of June, 1981.


                                             /s/ Peter G. Klacsmann
                                             -----------------------------------
                                                 Peter G. Klacsmann
                                                    Incorporator

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                              ARTICLES OF AMENDMENT

                                       OF

                         PETER G. KLACSMANN, M.D., P.C.
                      (A GEORGIA PROFESSIONAL CORPORATION)

                                    ARTICLE I

     The name of the corporation is "PETER G. KLACSMANN, M.D. P.C." (the
"Corporation").

                                   ARTICLE II

     Article I of the Articles of Incorporation is amended to state as follows:

          The name of the Corporation is "PETER G. KLACSMANN, M.D., INC."

                                   ARTICLE III

     Article III of the Articles of Incorporation is deleted in its entirety.

                                   ARTICLE IV

     Article IV of the Articles of Incorporation is amended to state as follows:

         The Corporation shall be governed by the Georgia Business Corporation
     Code.

                                    ARTICLE V

     Article VI of the Articles of Incorporation is deleted in its entirety.

                                   ARTICLE VI

     Article IX of the Articles of Incorporation is deleted in its entirety.

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                                   ARTICLE VII

     Pursuant to Section 14-2-1003 of the Official Code of Georgia, each
amendment described above has been duly adopted and approved by the Board of
Directors and the Shareholder of the Corporation as of the date of filing of
these Articles of Amendment.

                                  ARTICLE VIII

     The changes made by these Articles of Amendment shall be effective upon the
filing of these Articles of Amendment with the Secretary of State of the State
of Georgia.

                                   ARTICLE IX

     A request for publication of a notice of intent to file articles of
amendment which change the name of the Corporation and payment therefor have
been made as required by Section 14-2-1006.1(b) of the Official Code of Georgia.

     IN WITNESS WHEREOF, these Articles of Amendment have been executed by the
undersigned this 2nd day of December, 2002.


                                            PETER G. KLACKSMANN, M.D., P.C.

                                            /s/ Peter G. Klacsmann
                                            ------------------------------------
                                            By: Peter G. Klacsmann, M.D.
                                            As its: President

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