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                                                                    EXHIBIT 3.52

                             CODE OF REGULATIONS OF
                       MAHONING MEDICAL LABORATORIES, INC.

                                    ARTICLE I

                                     SHARES

     SECTION 1.1 - CERTIFICATES. The interest of each shareholder of the
corporation shall be evidenced by a certificate or certificates, each of which
shall bear a distinguishing number, the signature of the Chairman of the Board,
President, or Vice President and of the Secretary, Assistant Secretary,
Treasurer, or Assistant Treasurer, and such recitals as may be required by law.
A full record of each certificate so issued shall be maintained. No certificate
shall be issued for shares being sold by the corporation until such shares have
been paid for in full.

     SECTION 1.2 - TRANSFER. Certificates shall be transferable in person or by
written power of attorney, but no transfer shall be entered upon the record
until the previous certificate for such shares has been surrendered to the
corporation; provided, however, that the directors shall have authority to enact
such rules as they shall deem expedient from time to time concerning the
Issuance or transfer of certificates and to talk such actions in specific cases
as they deem proper concerning, lost, destroyed, or mutilated certificates.

                                   ARTICLE II

                                  SHAREHOLDERS

     SECTION 2.1 - ANNUAL MEETING. The annual meeting of the shareholders of the
corporation shall be held at such time as the directors determine. The meeting
shall be held at the office of the corporation or at such other location as the
directors determine.

     SECTION 2.2 - SPECIAL MEETINGS. Special meetings of the shareholders of the
corporation shall be held at such time and location as are designated in the
call therefor and may be called by: (a) the President; (b) the Vice President.
In the event of absence, disability or death of the President; (c) the directors
by action at a meeting; (d) a majority of the directors acting without a
meeting; or (e) person or persons who hold twenty-five percent (25%) or more
of the voting shares outstanding.

     SECTION 2.3 - NOTICE OF MEETINGS. Written notice of every annual or special
meeting of the shareholders stating the time, location, and purpose thereof
shall be given, as of a record date fixed by the directors, to each shareholder
entitled to vote thereat, or entitled to notice thereof as provided by law, by
mailing such notice to the last known address of each shareholder as it appears
on the records of the corporation, or by personal delivery, not less than seven
(7) nor more than sixty (60) days prior to such meeting. A shareholder may waive
in writing such notice either before or after the meeting, and notice shall be
waived by attendance

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at the meeting unless lack of proper notice is alleged prior to or at the
commencement of the meeting.

     SECTION 2.4 - QUORUM AND ADJOURNMENTS. The shareholders present in person
or by proxy representing a majority of the voting power of the corporation shall
constitute a quorum for a meeting shareholders; however, that at any meeting,
regardless of whether a quorum is present, the holders of a majority of the
voting shares represented thereat may adjourn from time to time without notice
other than by announcement at such meeting.

     SECTION 2.5 - VOTING. Only persons who appear as holders of voting shares
on the records of the corporation as of the close of business on the record date
for such meeting or, if no such record date shall have been fixed, the next day
preceding the day on which the meeting is held, shall be entitled to vote at
meetings of shareholders. Subscribers for voting shares shall have the right to
vote such subscribed shares while not in default of payment therefor.

     SECTION 2.6 - PROXIES. Any shareholder may be represented at a meeting of
shareholders for any purpose, including any vote to be taken thereat, by proxy
appointed in writing, executed by such shareholder, and delivered to the
Secretary or presiding officer at or before such meeting.

     SECTION 2.7 - ORDER OF BUSINESS. The order of business at a meeting of
shareholders shall be as follows, to the extent that the same is consistent with
the purpose of such meeting:

     (a)  Designated of a secretary for the meeting in the event the Secretary
          is absent thereform;

     (b)  Statement regarding giving of notice of meeting;

     (c)  Calling roll and filing of proxies with the Secretary;

     (d)  Reading and vote on approval of previously unapproved minutes;

     (e)  Report of President and reports of other officers;

     (f)  Consideration and approval of actions of officers and directors;

     (g)  Unfinished business;

     (h)  New business;

     (i)  Election of directors; and

     (j)  Adjournment.

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     SECTION 2.8 - ACTION WITHOUT A MEETING. Any action which may be authorized
or taken at a meeting of shareholders may be authorized or taken without a
meeting by writing or writings singed by all the shareholders who would be
entitled to notice of a meeting of the shareholders held for the purpose of such
action, which writing or writings shall be filed with or entered upon the
records of the Corporation.

                                   ARTICLE III

                                    DIRECTORS

     SECTION 3.1 - NUMBER. The number of directors shall be as determined by the
shareholders from time to time.

     SECTION 3.2 - ELECTION. At each meeting of the shareholders for the
election of directors, the nominees receiving the greatest number of votes shall
become the directors. Directors may be elected at any meeting of the
shareholders if the notice therefor states that one of the purposes of such
meeting is the election of directors.

     SECTION 3.3 - TENURE OF OFFICE. Each director shall hold office until the
annual meeting of shareholders next following his or her election and until his
or her successor is elected and qualified, or until his or her earlier
resignation, removal from office, or death. A director not re-elected at a
special meeting of shareholders, one of the purposes of which is the election of
a director for such post, shall be deemed to have been removed from office.

     SECTION 3.4 - VACANCIES. Whenever any vacancy shall occur among the
directors, the remaining directors may, by a vote of a majority of their number,
fill such vacancy.

     SECTION 3.5 - MEETINGS. Meetings of the directors shall be hold at such
time and location in Ohio as are designated in the call therefor and may be
called by: (a) the President; (b) the Vice President; or (c) any two directors.
Meetings of the directors may also be held at any time and location if all
directors are present or file written consents to such meeting. Meetings of the
directors may be held through any communications equipment if all persons
participating can hear each other.

     SECTION 3.6 - NOTICE OF MEETINGS. Written notice of all meetings of the
directors stating the time and location thereof shall be given by mail,
telegram, or cablegram to each director at his or her last known address, or
by personal delivery, not less than two (2) nor more than fourteen (14) days
prior to such meeting. A director may waive in writing such notice either
before or after the meeting, and notice shall be waived by attendance at the
meeting unless lack of proper notice is alleged prior to or at the
commencement of the meeting.

     SECTION 3.7 - QUORUM AND ADJOURNMENTS. A majority of the directors shall
coustitute a quorum; provided, however, that at any meeting, regardless of
whether a quorum

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is present, a majority of the directors present may adjourn from time to time
without notice other than by announcement at such meeting.

     SECTION 3.8 - VOTING. At any meeting of the directors at which a quorum is
present, all matters before the meeting, except for filling a vacancy, shall be
decided by the affirmative vote of not less than a majority of the directors
present.

     SECTION 3.9 - ACTION WITHOUT A MEETING. Any action which may be taken at a
meeting of the directors may be taken without a meeting in a written document
signed by all the directors.

     SECTION 3.10 - POWERS AND DUTIES. The directors shall:

     (a)  Exercise the powers of the corporation, conduct its business and
          affairs, and control its property;

     (b)  Elect and, in their discretion, remove of suspend officers;

     (c)  Fix and limit the powers and duties of all officers and fix the
          compensation of officers and directors;

     (d)  Designate a depository or depositories of funds of the corporation and
          the officers or other persons who shall be authorized to sign checks,
          notes, drafts, and other commercial paper on behalf of the
          corporation;

     (e)  Determine the business year upon which the corporation shall operate;

     (f)  In their discretion, adopt a seal for the corporation, which seal
          shall have inscribed thereon the name of the corporation and such
          other recitals as they deem appropriate; and

     (g)  In their discretion, enact, amend, or repeal such bylaws for their own
          government as may be consistent with the Articles of Incorporation and
          the Regulations.

                                   ARTICLE IV

                                    OFFICERS

     SECTION 4.1 - OFFICERS DESIGNATED. The officers of the corporation shall
consist of a President, a Vice President, a Secretary, a Treasurer, and such
other officers as the directors may deem appropriate.

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     SECTION 4.2 - ELECTION. The officers shall be elected by the directors. The
directors may fill any vacancy. The Chairman of the Board, if any, shall be a
director. No other officer need be a director or shareholder of the corporation.
One person may hold two or more offices, but no person shall execute any
document of the corporation in more than one capacity if such document is
required by law, the Articles, the Regulations, or the By-Laws to be executed,
acknowledged, or certified by two or more officers.

     SECTION 4.3 - TENURE OF OFFICE. Each officer shall hold office until the
first meeting of directors following the annual meeting of shareholders next
following his or her election and until his or her successor is elected and
qualified, or until his or her earlier resignation, removal from office, or
death.

     SECTION 4.4 - POWERS AND DUTIES. The following officers shall have the
following powers and duties:

     (a)  PRESIDENT. The President shall be the chief executive officer of the
          corporation and shall have general supervision over its property,
          business, and affairs, subject to the supervision and control of the
          directors. The President shall preside at all meetings of shareholders
          and directors.

     (b)  VICE PRESIDENT: The Vice President shall perform the duties of the
          President in the event of the absence, disability, or death of the
          President.

     (c)  SECRETARY. The Secretary shall record and maintain the minutes of all
          meetings of the shareholders and the directors in books provided for
          that purpose. The Secretary shall maintain records of the names and
          addresses of the shareholders of the corporation.

     (d)  TREASURER. The Treasurer shall maintain current and complete records
          of account, have custody of the funds of the corporation, deposit of
          such funds in such depositories at the directors may designate, and
          render to the directors upon their request statements of the financial
          condition of the corporation.

     SECTION 4.5 - DELEGATION OF DUTIES. The directors may delegate the duties
of any officer to any other officer and may require the performance of duties in
addition to those mentioned herein.

                                    ARTICLE V

                                 INDEMNIFICATION

     Each director, officer, and employee, or a former director, officer, or
employee, or any person who is serving or has served at the request of the
corporation as a director, officer, or

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employee of another corporation, shall be indemnified by the corporation against
expenses (including attorney fees), judgments, decrees, fines, penalties, or
amounts paid in settlement reasonably incurred in connection with the defense of
any pending or threatened or completed action, suit, or proceeding, whether
criminal, civil, investigative or administrative, to which he or she is or may
be a party by reason of being or having been such director, officer, or
employee; provided; (a) he or she is adjudicated or determined not to have been
negligent or guilty of misconduct in the performance of his duty to the
corporation; (b) he or she is determined to have acted in good faith and in a
manner in what he or she reasonably believed to be in or not opposed to the best
interest of the corporation; (c) in any matter the subject of a criminal action,
suit or proceeding, he or she is determined to have had no reasonable cause to
believe that his or her conduct was unlawful. The determination as to (b) and
(c) and, in the absence of adjudication by a court of competent, jurisdiction,
the determination as to (a), shall be made by the directors of the corporation
acting at a meeting at which a quorum consisting of directors who are not
parties to or threatened with any such action, suit, or proceeding is present.
Any director who is party to or threatened with any such action, suit, or
proceeding is present. Any director who is a party to or threatened with any
such action, suit, or proceeding is present. Any director who is a party to or
threatened with any such action, suit, or proceeding shall not be qualified to
vote and, if for this reason, a quorum of directors cannot be obtained to vote
on such indemnification, no indemnification shall be made unless such
indemnification is approved by: (a) the holders of a majority of the voting
shares of the corporation, excluding for the purposes hereof shares held or
controlled by every person who is a party to or threatened with any such action,
suit, or proceeding; or (b) a court of competent jurisdiction. Such right of
indemnification shall not be deemed exclusive of any other rights to which such
person may be entitled and shall inure to the benefit of the heirs, executors,
and administrators of such person.

                                   ARTICLE VI

                                   AMENDMENTS

     These Regulations may be amended, or new regulations may be enacted: (a) by
the affirmative vote of the holders of shares entitling them to exercise a
majority of the voting power of the corporation at any meeting called for such
purpose; or (b) without a meeting, by the written approval of the holders of
two-thirds of the voting shares of the corporation. In the event of amendment or
enactment of new regulations by such written consent, the Secretary of the
corporation shall mail a copy of such amendment of new regulations to each
shareholder who did not participate in the approval thereof.

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                         AMERIPATH YOUNGSTOWN LABS. INC.

                        AMENDMENTS TO CODE OF REGULATIONS

          The following provisions are applicable to and supplement the Sections
indicated and supercede anything to the contrary in the Code of Regulations:

SECTION 2.7 is deleted.

SECTION 3.1. The Board shall also have the right to determine the number of
directors within the limits of Section 1701.56 of the Ohio Revised Code.

ARTICLE V. The word "shall" is changed to "may" in the phrase "shall be
indemnified" in the first sentence of Article V.