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                                                                 EXHIBIT 3.32(a)

                           ARTICLES OF INCORPORATION

                                      OF

                              PRN RESEARCH, INC.

     The undersigned natural person of the age of eighteen (18) years or more,
acting as incorporator of a corporation under the Texas Business Corporation
Act, hereby adopts the following Articles of Incorporation for the corporation:

     1.  NAME. The name of the corporation is PRN Research, Inc.
         ----

     2.  DURATION. The period of its duration is perpetual.
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     3.  PURPOSE. The purpose for which the corporation is organized is the
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transaction of any or all lawful business.

     4.  SHARES. The aggregate number of shares which the corporation has
         ------
authority to issue is 1,000,000 shares of common voting stock, all of one class,
having no par value.

     5.  COMMENCEMENT OF BUSINESS.  The corporation will not commence business
         ------------------------
until it has received for the issuance of its shares at least One Thousand
Dollars ($1,000.00).

     6.  REGISTERED OFFICE AND AGENT.  The street address of the initial
         ---------------------------
registered office of the corporation is 8115 Preston Road, Suite 300, Dallas,
Texas 75225, and the name of the corporation's initial registered agent at that
address is George P. NcGinn.

     7.  INITIAL DIRECTOR.  The number of directors constituting the initial
         ----------------
board of directors is one (1), and the name and address of such person who is to
serve as director until the first annual meeting of the shareholders or until
his successor is elected and qualified is:

               NAME                               ADDRESS
               ----                               -------
               Merrick H. Reese                   8115 Preston Rd., Suite 300
                                                  Dallas, Texas  75225

     8.  INCORPORATOR. The name and address of the incorporator are George P.
         ------------
McGinn, 8115 Preston Rd., Suite 300, Dallas, Texas 75225.

     9.  DENIAL OF PREEMPTIVE RIGHTS. No shareholder or other person shall have
         ---------------------------
any preemptive right whatsoever.

     10. NON-CUMULATIVE VOTING. Cumulative voting by the shareholders of the
         ---------------------
corporation at any election for directors is expressly prohibited.

     11. INTERESTED DIRECTORS, OFFICERS AND SECURITY HOLDERS. No contract or
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transaction between the corporation and one or more of its directors, officers,
or
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security holders, or between the corporation and any other corporation,
partnership, association, or other organization in which one or more of its
directors, officers, or security holders are directors or officers or have a
financial interest, shall be void or voidable solely for this reason, solely
because the director, officer, or security holder is present at or participates
in the meeting of the board of directors, a committee thereof, or shareholders
which authorizes the contract or transaction, or solely because his or their
votes are counted for such purpose, if:

          (a) the material facts as to his relationship or interest and as to
     the contract or transaction are disclosed or are known to the board of
     directors or the committee, and the board of directors or committee in good
     faith authorized the contract or transaction by the affirmative vote of a
     majority of the disinterested directors, even though the disinterested
     directors be less than a quorum; or

          (b) the material facts as to his relationship or interest and as to
     the contract or transaction are disclosed or are known to the shareholders
     entitled to vote thereon, and the contract or transaction is specifically
     approved in good faith by vote of the shareholders; or

          (c) the contract or transaction is fair as to the corporation as of
     the time it is authorized, approved, or ratified by the board of directors,
     a committee thereof, or the shareholders.

Interested directors shall be counted in determining the presence of a quorum at
a meeting of the board of directors, a committee thereof, or shareholders which
authorizes the contract or transaction.

     12.  INDEMNITY. The corporation shall indemnify any person who is or was a
          ---------
director, officer, employee or agent of the corporation to the fullest extent
permitted by the Texas Business Corporation Act, as amended, but such
indemnification shall not be deemed exclusive of any other rights to which any
director, officer, employee or agent may be entitled. The corporation may
purchase and maintain insurance or another arrangement on behalf of any person
who is or was a director, officer, employee or agent of the corporation as
permitted by the Texas Business Corporation Act, as amended.

     13.  LIMITATION ON DIRECTOR LIABILITY. A director of the corporation is not
          --------------------------------
liable to the corporation or its shareholders or members for monetary damages
for an act or omission in the director's capacity as a director, except that
this article does not eliminate or limit the liability of a director for the
following:

              (1) a breach of a director's duty of loyalty to the corporation or
          its shareholders or members;

              (2) an act or omission not in good faith or that involves
          intentional misconduct or a knowing violation of the law;

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              (3) a transaction from which a director received an improper
          benefit, whether or not the benefit resulted from an action taken
          within the scope of the director's office;

              (4) an act or omission for which the liability of a director is
          expressly provided for by statute; or

              (5) an act related to an unlawful stock repurchase or payment of a
          dividend.

     14.  BYLAWS.  The initial bylaws shall be adopted by the board of directors
          ------
and the power to amend or repeal the bylaws or adopt new bylaws is vested in the
board of directors. The shareholders may also amend, repeal, or adopt the bylaws
even though the bylaws may be amended, repealed, or adopted by the board of
directors.

     15.  VOTE FOR CERTAIN MATTERS. With respect to any matter for which the
          ------------------------
affirmative vote of the holders of a specified portion of the shares entitled to
vote is required by the Texas Business Corporation Act, the affirmative vote of
the holders of a majority of the shares entitled to vote on such matter, rather
than the affirmative vote otherwise required by the Texas Business Corporation
Act, shall be the act of the shareholders.

     16.  ACTION BY SHAREHOLDERS WITHOUT A MEETING. Any action required by the
          ----------------------------------------
Texas Business Corporation Act or the corporations's bylaws to be taken at a
meeting of the shareholders, or any action which may be taken at any meeting of
the shareholders, may be taken without a meeting, without prior notice, and
without a vote, if a consent or consents in writing, setting forth the action so
taken, shall have been signed by the holder or holders of shares having not less
than the minimum number of votes that would be necessary to take such action at
a meeting at which the holders of all shares entitled to vote on the action were
present and voted.

     IN WITNESS WHEREOF, I have hereunto set my hand as of this 26th day of
January, 1996.


                                               _________________________________
                                               GEORGE P. MCGINN

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                             ARTICLES OF AMENDMENT
                                    TO THE
                           ARTICLES OF INCORPORATION
                                      OF
                              PRN RESEARCH, INC.

     Pursuant to the provisions of Article 4.04 of the Texas Business
Corporation Act, the undersigned corporation adopts the following Articles of
Amendment to its Articles of Incorporation:

     1.  The name of the corporation is PRN Research, inc.

     2.  The amendment to the Articles of Incorporation set forth below was
adopted by Written Consent of the Sole Shareholder of the corporation on
February 10, 2000.

     3.  The following amendment alters or changes Item number 1 of the original
Articles of Incorporation and the full text of item number 1, as amended hereby,
shall from and after the date hereof read in its entirety as follows:

               "___.  The name of the Corporation is US Oncology Research, Inc."

     4.  The amendment does not provide for an exchange, reclassification or
cancellation of issued shares.

     5.  The amendment does not effect a change in the amount of stated capital.

     6.  The number of shares of the corporation outstanding at the time of such
adoption was 1,000 shares of Common Stock, and the number of shares entitled to
vote on this amendment was 1,000 shares of Common Stock, all of which were voted
in favor of the amendment.

Dated: February 18, 2000

                                 PRN Research, Inc.
                                 a Texas corporation



                                 _______________________________________________
                                 L. Fred Pounds, Vice President and Secretary

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