<PAGE>

                                                                    EXHIBIT 10.1

[LOGO OF IMPERIAL BANK]

         Member FDIC

                                PROMISSORY NOTE

<TABLE>
<S>               <C>           <C>          <C>       <C>      <C>             <C>        <C>    <C>
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  Principal       Loan Date    Maturity      Loan No   Call     Collateral    Account    Officer   Initials
$2,990,000.00    12-19-2000   01-04-2021                            45      07416001246    631
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 References in the shaded area are for Lender's use only and do not limit the applicability of this document
                                        to any particular loan or item.
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</TABLE>

<TABLE>
<S>       <C>                                <C>
Borrower: MEDICAL CONTROL SERVICES, INC.     Lender: Imperial Bank
          5400 ORANGE AVENUE, SUITE 200              Secondary Market Loans
          CYPRESS, CA 90630                          9920 S. La Clenega Blvd., 14th Floor
                                                     Inglewood, CA 90301-4423
</TABLE>

 <TABLE>
 <S>                                   <C>                         <C>
======================================================================================================
 Principal Amount: $2,990,000.00  Initial Rate: 8.400%   Date of Note: December 19, 2000
 </TABLE>

 PROMISE TO PAY.   MEDICAL CONTROL SERVICES, INC. ("Borrower") promises to pay
 to Imperial Bank ("Lender"), or order, In lawful money of the United States of
 America, the principal amount of Two Million Nine Hundred Ninety Thousand &
 00/100 Dollars ($2,990,000.00), together with interest on the unpaid principal
 balance from December 19, 2000, until paid in full.

 PAYMENT. Subject to any payment changes resulting from changes in the index,
 Borrower will pay this loan in 239 regular payments of $25,983.97 each and one
 irregular last payment estimated at $25,981.61. Borrower's first payment is due
 February 4, 2001, and all subsequent payments are due on the same day of each
 month after that. Borrower's final payment due January 4, 2021, will be for all
 principal and all accrued interest not yet paid. Payments include principle and
 interest. The annual interest rate for this Note is computed on a 365/360
 basis; that is, by applying the ratio of the annual interest rate over a year
 of 360 days, multiplied by the outstanding principal balance, multiplied by the
 actual number of days the principal balance is outstanding. Borrower will pay
 Lender at Lender's address shown above or at such other place as Lender may
 designate in writing. Unless otherwise agreed or required by applicable law,
 payments will be applied first to any unpaid collection costs and any late
 charges, then to any unpaid interest, and any remaining amount to principal.

 VARIABLE INTEREST RATE. The interest rate on this Note is subject to change
 from time to time based on changes in an independent index which is the
 International Swaps and Derivatives Association ("ISDA") mid-market par swap
 rate for a swap period of five (5) years for a fixed rate payer in return for
 receiving three month LIBOR, based on rates published on electronic publishing
 services available to Lender at 9:00 AM Pacific Time as of any date of
 determination (the "Index"). The Index is not necessarily the lowest rate
 charged by Lender on its loans. If the Index becomes unavailable during the
 term of this loan, Lender may designate a substitute index after notice to
 Borrower. Lender will tell Borrower the current Index rate upon Borrower's
 request. Borrower understands that Lender may make loans based on other rates
 as well. The interest rate change will not occur more often than each five (5)
 years. The Index currently is 6.150%. The Interest rate to be applied to the
 unpaid principal balance of this Note will be at a rate of 2.250 percentage
 points over the Index, resulting in an initial rate of 8.400%. NOTICE: Under no
 circumstances will the interest rate on this Note be more than the maximum rate
 allowed by applicable law. Whenever increases occur in the interest rate,
 Lender, at its option, may do one or more of the following: (a) increase
 Borrower's payments to ensure Borrower's loan will pay off by its original
 final maturity date, (b) increase Borrower's payments to cover accruing
 interest, (c) increase the number of Borrower's payments, and (d) continue
 Borrower's payments at the same amount and increase Borrower's final payment.

 PREPAYMENT PENALTY; MINIMUM INTEREST CHARGE. Borrower agrees that all loan fees
 and other prepaid finance charges are earned fully as of the date of the loan
 and will not be subject to refund upon early payment (whether voluntary or as a
 result of default), except as otherwise required by law. In any event, even
 upon full prepayment of this Note, Borrower understands that Lender is entitled
 to a minimum interest charge of $250.00. Upon prepayment of this Note, Lender
 is entitled to the following prepayment penalty: SEE EXHIBIT "A" ATTACHED
 HERETO AND MADE A PART HEREOF BY THIS REFERENCE. Other than Borrower's
 obligation to pay any minimum interest charge and prepayment penalty, Borrower
 may pay all or a portion of the amount owed earlier than it is due. Early
 payments will not, unless agreed to by Lender in writing, relieve Borrower of
 Borrower's obligation to continue to make payments under the payment schedule.
 Rather, they will reduce the principal balance due and may result in Borrower
 making fewer payments.

 LATE CHARGE. If a payment is 10 days or more late, Borrower will be charged
 5.000% of the unpaid portion of the regularly scheduled payment.

 DEFAULT. Borrower will be in default if any of the following happens: (a)
 Borrower fails to make any payment when due. (b) Borrower breaks any promise
 Borrower has made to Lender, or Borrower fails to comply with or to perform
 when due any other term, obligation, covenant, or condition contained in this
 Note or any agreement related to this Note, or in any other agreement or loan
 Borrower has with Lender. (c) Borrower defaults under any loan, extension of
 credit, security agreement, purchase or sales agreement, or any other
 agreement, in favor of any other creditor or person that may materially affect
 any of Borrower's property or Borrower's ability to repay this Note or perform
 Borrower's obligations under this Note or any of the Related Documents. (d) Any
 representation or statement made or furnished to Lender by Borrower or on
 Borrower's behalf is false or misleading in any material respect either now or
 at the time made or furnished. (e) Borrower becomes insolvent, a receiver is
 appointed for any part of Borrower's property, Borrower makes an assignment for
 the benefit of creditors, or any proceeding is commenced either by Borrower or
 against Borrower under any bankruptcy or insolvency laws. (f) Any creditor
 tries to take any of Borrower's property on or in which Lender has a lien or
 security interest. This includes a garnishment of any of Borrower's accounts
 with Lender. (g) Any guarantor dies or any of the other events described in
 this default section occurs with respect to any guarantor of this Note. (h) A
 material adverse change occurs in Borrower's financial condition, or Lender
 believes the prospect of payment or performance of the Indebtedness is
 impaired.

 If any default, other than a default in payment, is curable and if Borrower has
 not been given a notice of a breach of the same provision of this Note within
 the preceding twelve (12) months, it may be cured (and no event of default will
 have occurred) if Borrower, after receiving written notice from Lender
 demanding cure of such default: (a) cures the default within ten (10) days; or
 (b) if the cure requires more than ten (10) days, immediately initiates steps
 which Lender deems in Lender's sole discretion to be sufficient to cure the
 default and thereafter continues and completes all reasonable and necessary
 steps sufficient to produce compliance as soon as reasonably practical.

 LENDER'S RIGHTS. Upon default, Lender may declare the entire unpaid principal
 balance on this Note and all accrued unpaid interest immediately due, without
 notice, and then Borrower will pay that amount. Upon Borrower's failure to pay
 all amounts declared due pursuant to this section, including failure to pay
 upon final maturity, Lender, at its option, may also, if permitted under
 applicable law, do one or both of the following: (a) increase the variable
 interest rate on this Note to 7.250 percentage points over the Index, and (b)
 add any unpaid accrued interest to principal and such sum will bear interest
 therefrom until paid at the rate provided in this Note (including any increased
 rate). Lender may hire or pay someone else to help collect this Note if
 Borrower does not pay. Borrower also will pay Lender that amount. This
 includes, subject to any limits under applicable law Lender's attorneys' fees
 and Lender's legal expenses whether or not there is a lawsuit, including
 attorneys' fees and legal expenses for bankruptcy proceedings (including
 efforts to modify or vacate any automatic stay or injunction), appeals, and any
 anticipated post-judgment collection services. Borrower also will pay any court
 costs, in addition to all other sums provided by law. This Note has been
 delivered to Lender and accepted by Lender in the State of California. If there
 is a lawsuit, Borrower agrees upon Lender's request to submit to the
 jurisdiction of the courts of Los Angeles County, the State of California.
 Lender and Borrower hereby waive the right to any jury trial in any action,
 proceeding, or counterclaim brought by either Lender or Borrower against the
 other. (Initial Here _______ ) This Note shall be governed by and construed in
 accordance with the laws of the State of California.

 DISHONORED ITEM FEE. Borrower will pay a fee to Lender of $25.00 if Borrower
 makes a payment on Borrower's loan and the check or preauthorized charge with
 which Borrower pays is later dishonored.

 COLLATERAL. Borrower acknowledges this Note is secured by a Deed of Trust dated
 December 19, 2000, to a trustee in favor of Lender on real property located in
 Orange County, State of California. That agreement contains the following due
 on sale provision: Lender may, at its option, declare immediately due and
 payable all sums secured by this Note upon the sale or transfer, without the
 Lender's prior written consent, of all or any part of the Real Property, or any
 interest in the Real Property. A "sale or transfer" means the conveyance of
 Real Property or any right, title or interest therein; whether legal,
 beneficial or equitable; whether voluntary or involuntary; whether by outright
 sale, deed, installment sale contract, land contract, for deed, leasehold
 interest with a term greater than three (3) years, lease-option contract, or by
 sale, assignment, or transfer of any beneficial interest in or to any land
 trust holding title to the Real Property, or by any other method of conveyance
 of Real Property interest. If any Trustor is a corporation, partnership or
 limited liability company, transfer also includes any change in ownership of
 more than twenty-five percent (25%) of the voting stock, partnership interests
 or limited liability company interests, as the case may be, of Trustor.
 However, this option shall not be exercised by Lender if such exercise is
 prohibited by applicable law.

 REFERENCE PROVISION. 1. Other than (i) non-judicial foreclosure and all matters
 in connection therewith regarding security interests in real or personal
 property; or (ii) the appointment of a receiver, or the exercise of other
 provisional remedies (any and all of which may be initiated pursuant to
 applicable law), each controversy, dispute or claim between the parties arising
 out of or relating to this document ("Agreement"), which controversy,


<PAGE>

12-19-2000                      PROMISSORY NOTE                           Page 2
                                   (Continued)

================================================================================

dispute or claim is not settled in writing within thirty (30) days after the
"Claim Date" (defined as the date on which a party subject to the Agreement
gives written notice to all other parties that a controversy, dispute or claim
exists), will be settled by a reference proceeding in California in accordance
with the provisions of Section 638 et seq. of the California Code of Civil
Procedure, or their successor section ("CCP"), which shall constitute the
exclusive remedy for the settlement of any controversy, dispute or claim
concerning this Agreement, including whether such controversy, dispute or claim
is subject to the reference proceeding and except as set forth above, the
parties waive their rights to initiate any legal proceedings against each other
in any court or jurisdiction other than the Superior Court in the County where
the Real Property, if any, is located or Los Angeles County if none (the
"Court"). The referee shall be a retired Judge of the Court selected by mutual
agreement of the parties, and if they cannot so agree within forty-five (45)
days after the Claim Date, the referee shall be promptly selected by the
Presiding Judge of the Court (or his representative). The referee shall be
appointed to sit as a temporary judge, with all of the powers for a temporary
judge, as authorized by law, and upon selection should take and subscribe to the
oath of office as provided for in Rule 244 of the California Rules of Court (or
any subsequently enacted Rule). Each party shall have one peremptory challenge
pursuant to CCP 170.6. The referee shall (a) be requested to set the matter for
hearing within sixty (60) days after the Claim Date and (b) try any and all
issues of law or fact and report a statement of decision upon them, if possible,
within ninety (90) days of the Claim Date. Any decision rendered by the referee
will be final, binding and conclusive and judgment shall be entered pursuant to
CCP 644 in any court in the State of California having jurisdiction. Any party
may apply for a reference proceeding at any time after thirty (30) days
following notice to any other party of the nature of the controversy, dispute or
claim, by filing a petition for a hearing and/or trail. All discovery permitted
by this Agreement shall be completed no later than fifteen (15) days before the
first hearing date established by the referee. The referee may extend such
period in the event of a party's refusal to provide requested discovery for any
reason whatsoever, including, without limitation, legal objections raised to
such discovery or unavailability of a witness due to absence or illness. No
party shall be entitled to "priority" in conducting discovery. Depositions may
be taken by either party upon seven (7) days written notice, and request for
production or inspection of documents shall be responded to within ten (10) days
after service. All disputes relating to discovery which cannot be resolved by
the parties shall be submitted to the referee whose decision shall be final and
binding upon the parties. Pending appointment of the referee as provided herein,
the Superior Court is empowered to issue temporary and/or provisional remedies,
as appropriate.

2. Except as expressly set forth in this Agreement, the referee shall determine
the manner in which the reference proceeding is conducted including the time and
place of all hearings, the order of presentation of evidence, and all other
questions that arise with respect to the course of the reference proceeding. All
proceedings and hearings conducted before the referee, except for trial, shall
be conducted without a court reporter, except that when any party so requests, a
court reporter will be used at any hearing conducted before the referee. The
party making such a request shall have the obligation to arrange for and pay for
the court reporter. The costs of the court reporter at the trial shall be borne
equally by the parties.

3. The referee shall be required to determine all issues in accordance with
existing case law and the statutory laws of the State of California. The rules
of evidence applicable to proceedings at law in the State of California will be
applicable to the reference proceeding. The referee shall be empowered to enter
equitable as well as legal relief, to provide all temporary and/or provisional
remedies and to enter equitable orders that will be binding upon the parties.
The referee shall issue a single judgment at the close of the reference
proceeding which shall dispose of all of the claims of the parties that are the
subject of the reference. The parties hereto expressly reserve the right to
contest or appeal from the final judgment or any appealable order or appealable
judgment entered by the referee. The parties hereto expressly reserve the right
to findings of fact, conclusions of law, a written statement of decision, and
the right to move for a new trial or a different judgment, which new trial, if
granted, is also to be a reference proceeding under this provision.

4. In the event that the enabling legislation which provides for appointment of
a referee is repealed (and no successor statute is enacted), any dispute between
the parties that would otherwise be determined by the reference procedure herein
described will be resolved and determined by arbitration. The arbitration will
be conducted by a retired judge of the Court, in accordance with the California
Arbitration Act, 1280 through 1294.2 of the CCP as amended from time to time.
The limitations with respect to discovery as set forth hereinabove shall apply
to any such arbitration proceeding.

BUSINESS LOAN AGREEMENT. This Note is subject to the provisions of the Business
Loan Agreement dated December 19, 2000 and all amendments thereto and
replacements therefor.

INTEREST RATE RECALCULATION. Notwithstanding the Provisions contained under
"Variable Interest Rate", on February 5, 2006; February 5, 2011 and February 5,
2016 (collectively, "Recalculation Dates"), the interest rate on this Note shall
be recalculated to an interest rate equal to the Index as of said Recalculation
Date, plus two and one quarter percent (2.250%) per annum.

PAYMENT RECALCULATION. Notwithstanding the provisions contained under "Payment",
on each of the Recalculation Dates, the monthly payments shall be recalculated
based on the interest rate under this Note, as concurrently calculated on said
Recalculation Date, the then outstanding principal balance of this Note and the
original amortization period of two hundred forty (240) months less the number
of months which have elapsed since the date hereof.

GENERAL PROVISIONS. Lender may delay or forgo enforcing any of its rights or
remedies under this Note without losing them. Borrower and any other person who
signs, guarantees or endorses this Note, to the extent allowed by law, waive any
applicable statute of limitations, presentment, demand for payment, protest and
notice of dishonor. Upon any change in the terms of this Note, and unless
otherwise expressly stated in writing no party who signs this Note, whether as
maker, guarantor, accommodation maker or endorser, shall be released from
liability. All such parties agree that Lender may renew or extend (repeatedly
and for any length of time) this loan, or release any party or guarantor or
collateral; or impair, fail to realize upon or perfect Lender's security
interest in the collateral; and take any other action deemed necessary by Lender
without the consent of or notice to anyone. All such parties also agree that
Lender may modify this loan without the consent of or notice to anyone other
than the party with whom the modification is made.

PRIOR TO SIGNING THIS NOTE, BORROWER READ AND UNDERSTOOD ALL THE PROVISIONS OF
THIS NOTE, INCLUDING THE VARIABLE INTEREST RATE PROVISIONS. BORROWER AGREES TO
THE TERMS OF THE NOTE AND ACKNOWLEDGES RECEIPT OF A COMPLETED COPY OF THE NOTE.

BORROWER:

MEDICAL CONTROL SERVICES, INC.



By:___________________________________
   MANUEL OCCIANO, PRESIDENT
<PAGE>

EXHIBIT "A" ATTACHED TO THAT CERTAIN PROMISSORY NOTE DATED DECEMBER 19, 2000
EXECUTED BY MEDICAL CONTROL SERVICES, INC.:


                             ADDITIONAL PROVISIONS
                             ---------------------



 PREPAYMENT PENALTY PROVISION
 ----------------------------

 During each Loan Year during the term of this Note, Obligor shall have the
 right to prepay, in whole or in part, up to and including twenty percent (20%)
 of the outstanding principal balance of this Note as of the first calendar day
 of said Loan Year, without penalty.

 During each Loan Year during the term of this Note, Obligor shall have the
 right to prepay, in whole or in part, greater than twenty percent (20%) of the
 outstanding principal balance of this Note as of the first calendar day of said
 Loan Year, provided that, as a condition precedent to Obligor's right to so
 prepay the outstanding principal balance of this Note, Obligor shall pay to
 Lender a prepayment penalty calculated as follows:

        Loan Year of Prepayment        Prepayment Penalty
        -----------------------        ------------------

        Loan Years 1 through 6         Five percent (5%) of the aggregate amount
                                       of the outstanding principal balance of
                                       this Note prepaid by Obligor during said
                                       Loan Year which exceeds twenty percent
                                       (20%) of the outstanding principal
                                       balance of this Note as of the first
                                       calendar day of said Loan Year.

        Loan Year 7                    Four percent (4%) of the aggregate amount
                                       of the outstanding principal balance of
                                       this Note prepaid by Obligor during said
                                       Loan Year which exceeds twenty percent
                                       (20%) of the outstanding principal
                                       balance of this Note as of the first
                                       calendar day of said Loan Year.

        Loan Year 8                    Three percent (3%) of the aggregate
                                       amount of the outstanding principal
                                       balance of this Note prepaid by Obligor
                                       during said Loan Year which exceeds
                                       twenty percent (20%) of the outstanding
                                       principal balance of this Note as of the
                                       first calendar day of said Loan Year.

        Loan Year 9                    Two percent (2%) of the aggregate amount
                                       of the outstanding principal balance of
                                       this Note prepaid by Obligor during said
                                       Loan Year which exceeds twenty percent
                                       (20%) of the outstanding principal
                                       balance of this Note as of the first
                                       calendar day of said Loan Year.

        Loan Year 10                   One percent (1%) of the aggregate amount
                                       of the outstanding principal balance of
                                       this Note prepaid by Obligor during said
                                       Loan Year which exceeds twenty percent
                                       (20%) of the outstanding principal
                                       balance of this Note as of the first
                                       calendar day of said Loan Year.


<PAGE>

Notwithstanding the foregoing, Obligor shall have the right to prepay, in whole
or in part, the entire outstanding principal balance of this Note, without
penalty, provided that Obligor delivers said prepayment to Lender no earlier
than ninety (90) calendar days prior to the expiration of the Fifth, and Tenth
Loan Years, and not later than the last calendar day of the Fifth and Tenth Loan
Years.

For the purposes of this Note, a "Loan Year" shall mean a full 360-day period,
commencing as of the Initial Disbursement Date, and each full consecutive 360-
day period thereafter.

BORROWER:

MEDICAL CONTROL SERVICES, INC.


By:____________________________
   Manuel Occiano, President