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                                                                   Exhibit 10.21


                                PROMISSORY NOTE

$4,000,000.00

                                                                  August 2, 1999

     For value received, PARK MEDICAL ASSOCIATES GENERAL PARTNERSHIP, a North
Carolina general partnership ("BORROWER"), promises and agrees to pay to the
order of GENERAL ELECTRIC CAPITAL CORPORATION, a New York corporation
("LENDER"), in lawful money of the United States of America, the principal sum
of FOUR MILLION AND N0/100 DOLLARS ($4,000,000.00) or so much thereof as may be
outstanding under the Loan Agreement of even date herewith between Borrower and
Lender (the "LOAN AGREEMENT"), with interest on the unpaid principal sum owing
thereunder at the rate or rates or in the amounts computed in accordance with
the Loan Agreement, together with all other amounts due Lender under the Loan
Agreement, all payable in the manner and at the time or times provided in the
Loan Agreement. Capitalized terms used herein, but not defined, shall have the
meanings assigned to them in the Loan Agreement.

     If not sooner due and payable in accordance with the Loan Agreement,
Borrower shall pay to Lender all amounts due and unpaid under the Loan Agreement
on September 1, 2009, or on any earlier Maturity Date as set forth in the Loan
Agreement. Unless otherwise specified in writing by Lender, all payments
hereunder shall be paid to Lender at c/o GE Capital Loan Services, Inc., P. 0.
Box 420250, Houston, Texas 77042. Lender reserves the right to require any
payment on this Note, whether such payment is a regular installment, prepayment
or final payment, to be by wired federal funds or other immediately available
funds.

     Borrower, co-makers, sureties, endorsers and guarantors, and each of them,
expressly waive demand and presentment for payment, notice of nonpayment,
protest, notice of protest, notice of dishonor, notice of intent to accelerate
the maturity hereof, notice of the acceleration of the maturity hereof, bringing
of suit and diligence in taking any action to collect amounts called for
hereunder and in the handling of securities at any time existing in connection
herewith; such parties are and shall be jointly, severally, directly and
primarily liable for the payment of all sums owing and to be owing hereon,
regardless of and without any notice, diligence, act or omission as or with
respect to the collection of any amount called for hereunder or in connection
with any right, lien, interest or property at any and all times had or existing
as security for any amount called for hereunder.

     This Note evidences all advances made, interest due and all amounts
otherwise owed to Lender under the Loan Agreement. This Note is executed in
conjunction with the Loan Agreement and is secured by the liens and security
interests created under the Loan Documents (including those arising under the
Mortgage). Reference is made to the Loan Agreement for provisions relating to
repayment of the indebtedness evidenced by this Note, including mandatory
repayment, acceleration following default, late charges, default rate of
interest, limitations on interest, and restrictions on prepayment.

     Borrower's liability hereunder is subject to the limitation on liability
provisions of Article 12 of the Loan Agreement. This Note has been executed and
delivered in and shall be construed in accordance with and governed by the laws
of the State of North Carolina and of the United States of America.

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EXECUTED as of the date first written above.

                                    PARK MEDICAL ASSOCIATES GENERAL PARTNERSHIP,
                                    a North Carolina general partnership

                                    By: P-51 ASSOCIATES,
                                        a North Carolina general partnership,
                                        Its: Managing General Partner

                                    By: Diane Brackett Company, Inc.,
                                        a North Carolina corporation,
                                        Its: Managing General Partner


                                                                          [SEAL]

                                        By: /s/ Diane B. Rivers
                                           ------------------------------------
                                           Diane B. Rivers, President

ATTEST:
/s/ Selma Inman
----------------------------
Selma Inman, Secretary

[Corporate Seal]