Exhibit 3.79



                          FIRST AMENDMENT TO BY LAWS
                                      OF
                         MAXUM HEALTH SERVICES CORP.

This First Amendment to By Laws (this "Amendment") of Maxum Health Services
Corp. is effective as of October 26, 2005.

1.      Article 6 "OFFICERS" of the By Laws is hereby deleted in its entirety
and replaced with the following:

                                 "ARTICLE 6.
                                 -----------
                                  OFFICERS

        Section 6.1     Number; Security.  The executive officers of
the corporation shall be the president, one or more vice presidents (including
an executive vice president, if the board of directors so determines), a chief
financial officer, a secretary and a treasurer.  Any two or more offices may be
held by the same person, except the offices of president and secretary.

        Section 6.2     Election; Term of Office.  The executive officers of
the corporation shall be elected annually by the board of directors, and each
such officer shall hold office until the next annual meeting of the board of
directors and until the election of his or her successor, subject to the
provisions of Section 6.4.

        Section 6.3     Subordinate Officers.  The board of directors
may appoint subordinate officers (including assistant secretaries and assistant
treasurers), agents or employees, each of whom shall hold office for such
period and have such powers and duties as the board of directors determines.
The board of directors may delegate to any executive officer or to any
committee the power to appoint and define the powers and duties of any
subordinate officers, agents or employees.

        Section 6.4     Resignation and Removal of Officers.  Any officer may
resign at any time by delivering his or her resignation in writing to the
president or secretary of the corporation, to take effect at the time specified
in the resignation; the acceptance of a resignation, unless required by its
terms, shall not be necessary to make it effective.  Any officer appointed by
the board of directors or appointed by an executive officer or by a committee
may be removed by the board of directors either with or without cause, and in
the case of an officer appointed by an executive officer or by a committee, by
the officer or committee who appointed him or her or by the president.

        Section 6.5     Vacancies.  A vacancy in any office may be
filled for the unexpired term in the manner prescribed in Sections 6.2 and 6.3
of these by laws for election or appointment to the office.

        Section 6.6     The President.  The president shall be the
chief executive officer of the corporation and shall preside at all meetings of
the board of directors and of the stockholders.  Subject to the control of the
board of directors and the chairman of the board, he or she shall have general
supervision over the business of the corporation and shall have such other
powers

and duties as presidents of corporations usually have or as the board of
directors assigns to him or her.

        Section 6.7     Vice President.  Each vice president shall have
such powers and duties as the board of directors or the president assigns to
him or her.

        Section 6.8     Chief Financial Officer.  The chief financial
officer of the corporation shall have general supervision over all financial
matters of the corporation and shall have such other powers and duties as chief
financial officers usually have or as the board of directors or the president
assigns to him or her.

        Section 6.9     Treasurer.  The treasurer shall be in charge of
the corporation's books and accounts.  Subject to the control of the board of
directors, he or she shall have such other powers and duties as the board of
directors or the president assigns to him or her.

        Section 6.10    Secretary.  The secretary shall be the secretary of,
and keep the minutes of, all meetings of the board of directors and of the
stockholders, shall be responsible for giving notice of all meetings of
stockholders and of the board of directors, and shall keep the seal and, when
authorized by the board of directors, apply it to any instrument requiring it.
Subject to the control of the board of directors, he or she shall have such
powers and duties as the board of directors or the president assigns to him or
her.  In the absence of the secretary from any meeting, the minutes shall be
kept by the person appointed for that purpose by the presiding officer.

        Section 6.11    Salaries.  The board of directors may fix the officers'
salaries, if any, or it may authorize the president to fix the salary of any
other officer."

2.      Except as amended by this Amendment, the By Laws shall remain in full
force and effect; provided, however that wherever the terms and conditions of
this Amendment and the terms and conditions of the By Laws conflict, the terms
and conditions of this Amendment shall be deemed to supersede the conflicting
terms of the By Laws.