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                                                                   Exhibit 10.45


                             STOCK PLEDGE AGREEMENT
                         (Ampro Medical Services, Inc.)


DATE:           January 31, 1999

PARTIES:

         Pledgor:          AMERICAN PROFESSIONAL HOLDINGS, INC.
                           a Utah corporation
                           10405 E. Northwest, Highway #109
                           Dallas, Texas 75238

         Secured Party:    David Kremser, Bernice Kremser,
                           Holly Kremser, Michael Kremser,
                           Stanley Kremser and
                           ELK MEADOWS INVESTMENTS, L.L.C.
                           784 Yankee Creek Road
                           Evergreen, CO 80439

RECITALS:

         A. In accordance with the terms of the Debtors' First Amended Joint
Plan of Reorganization dated October 15, 1998 (as amended and supplemented),
confirmed by a final Order of the United States Bankruptcy Court effective
January 20, 1999 (the "Plan"), Pledgor desires to borrow, and Secured Party
desires to lend, the sum of One Million Three Hundred Fifty-Three Thousand Seven
Hundred Four Dollars ($1,353,704) (the "Loan") to Pledgor pursuant to a
promissory note of even date herewith (the "Note"). All documents evidencing and
or securing the Loan may be hereinafter referred to as the "Loan Documents."

         B. Pledgor owns one hundred percent (100%) of the issued and
outstanding capital stock of AMPRO MEDICAL SERVICES, INC., a Texas corporation
("AMPRO").

         C. In order to induce Secured Party to make the Loan to Pledgor,
Pledgor desires to grant a security interest in, and, pledge, sign and transfer,
all of Pledgor's right, title and interest in and to the Shares, to Secured
Party.

         NOW, THEREFORE, for good and valuable consideration, the receipt of
which is hereby acknowledged, the parties agree as follows:

         1. Pledge. Pledgor hereby grants to Secured Party a security interest
in the Shares together with all rights thereof or arising therefrom, all
additions thereto, dividends, options, warrants and payments arising thereunder,
all proceeds from the sale or other disposition thereof,


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and all substitutions therefor (collectively the "Collateral"), as security for
all of the Pledgor's obligations to Secured Party under the Note and any and all
of the Loan Documents. Upon execution of this Agreement, Pledgor shall deliver
to Secured Party stock power(s) and assignment(s) separate from certificate for
the certificates representing the Shares endorsed in blank. The books of the
issuer of such Shares shall contain a legend to reflect such pledge of the
Shares hereunder.

         2. Covenants and Representations. Pledgor agrees not to knowingly take
any action which would adversely affect the value of the Collateral or which
would encumber, dilute or cloud Pledgor's title or interest therein. Pledgor
makes the following representations, warranties, and covenants:

                  (a) Pledgor is and will continue to be the owner of the
         Collateral, free of any liens, security interests or assignments other
         than the security interest created by this Agreement;

                  (b) Pledgor shall deliver to Secured Party and Secured Party
         shall retain physical possession of all stock certificates and other
         instruments and documents representing or evidencing any of the
         Collateral, which stock certificates shall be duly endorsed in blank;

                  (c) Pledgor will not modify or amend the instruments or
         documents constituting the Collateral, except as required by law, court
         order, or regulation, or make any compromise, adjustment, settlement or
         termination in connection therewith;

                  (d) Pledgor will at all times defend the Collateral against
         any and all claims of any person, adverse to the claims of Secured
         Party upon Secured Party's request;

                  (e) upon the occurrence of an Event of Default (as defined in
         paragraph 5 hereof and which is continuing) Pledgor will accept no
         payments, distributions or dividends on the Collateral and shall remit
         to Secured Party any payment or distribution received;

                  (f) Pledgor has the full power and authority to enter into
         this Agreement, and the persons executing this Agreement on behalf of
         Pledgor have been duly authorized to act on behalf of Pledgor in the
         execution hereof;

                  (g) other than Pledgor, there are no parties who assert any
         type of ownership interest whatsoever in the Shares;

                  (h) other than this Agreement, there are no agreements which
         impose any conditions or restrictions on the Shares;

                  (i) all of the Shares have been duly authorized, validly
         issued and are fully paid and non-assessable;



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                  (j) Pledgor, as stockholder, shall not vote for, ratify,
         accept, accede to, or approve any proposed transaction concerning the
         Collateral which would have a material adverse effect on the rights of
         Secured Party hereunder; and

                  (k) The Shares represent one hundred percent (100%) of the
         issued and outstanding stock of AMPRO, and there are no agreements in
         effect which require or obligate AMPRO to issue any additional shares
         of stock of AMPRO and there are no outstanding options to purchase any
         shares of stock of AMPRO. There will be no agreements in effect which
         require or obligate AMPRO to issue any additional shares of stock of
         AMPRO and there will be no outstanding options to purchase any shares
         of stock of AMPRO.

         3. Delivery of Instruments; Adjustments. Pledgor has delivered to
Secured Party, all stock certificates and all documents evidencing any ownership
of the Collateral or which are necessary or convenient for Secured Party to
exercise any of Secured Party's rights hereunder. If, during the term of this
Agreement, any stock dividends, reclassification, readjustments or other changes
are declared or made in the capital structure of any corporation represented by
the Collateral, or if any subscription or other options are exercisable with
respect to the Collateral, all such new, substitute or additional shares or
other securities, rights or interests issued shall be delivered to and held by
Secured Party subject to this Agreement in the same manner as the Collateral.

         4. Voting. So long as Pledgor is not in default hereunder, any
Collateral may be voted by the Pledgor at all meetings of stockholders, subject
to the restrictions of Paragraph 2(j).

         5. Events of Default. Any one or more of the following will constitute
an event of default ("Event of Default") under this Agreement:

                  (a) any event occurs which constitutes an Event of Default
         under any of the Loan Documents;

                  (b) if Pledgor fails to pay or perform any of its material
         obligations contained in paragraphs 2, 7 and 8 of this Agreement and
         which failure is not cured upon 30 days written notice by Secured Party
         to Pledgor;

                  (c) any covenant, condition, agreement, representation or
         warranty made by Pledgor to Secured Party in this Agreement is
         materially breached or proves untrue in any material respect and is not
         cured upon 30 days written notice by Secured Party to Pledgor.

         6. Remedies on Default. Upon the occurrence and during the continuance
of an Event of Default, Secured Party may exercise any or all of the rights and
remedies provided (a) by this Agreement, and/or (b) by any other applicable law.
Without limiting the generality of the foregoing, upon the occurrence and
continuance of an Event of Default, Secured Party may (i) instruct the secretary
of AMPRO to pay all dividends to Secured Party, and (ii) sell the Collateral or
any part 


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thereof, without recourse to judicial proceedings, with the right to
bid for and buy, free from any right of redemption, upon ten (10) days' notice
(which notice is agreed to be reasonable notice for the purposes hereof) to the
Pledgor, of the time and place of sale, for cash, upon credit or for future
delivery, at Secured Party's option and in Secured Party's complete discretion:

                  (a) at a public sale, including a sale at any broker's board
         or exchange;

                  (b) at private sale in any commercially reasonable manner
         which will not require the Collateral, or any part thereof, to be
         registered in accordance with the Securities Act of 1933, as amended,
         or the rules and regulations promulgated thereunder, or any other law
         or regulation. Secured Party is also hereby authorized, but not
         obligated, to take such actions, give such notices, obtain such
         consents, and do such other things as it may deem required or
         appropriate in the event of sale or disposition of any of the
         Collateral.

         In connection with the sale of any of the Collateral, Secured Party is
authorized, but not obligated, to limit prospective purchasers to the extent
deemed necessary or desirable by Secured Party to render such sale exempt from
the registration requirements of the Securities Act of 1933, as amended, and any
applicable state securities laws, and any sale of the Collateral so made in good
faith by Secured Party shall be deemed to be commercially reasonable. In
connection with any such sale or other disposition in accordance with the
provision hereof, Secured Party shall be authorized to deliver the Stock to or
upon the order of Secured Party.

         7. Taxes. Pledgor shall pay promptly, when due, any and all property
taxes, excise taxes (however called) and other taxes, assessments, duties and
other charges, which, if unpaid, might by law or otherwise become a lien or
charge upon the Collateral (including any and all interest, penalties and
related provisional fees) imposed, levied or assessed against the Collateral, or
upon or measured by the use, ownership, possession or operation thereof, or in
respect to this Agreement or the security interest in the Collateral granted and
conveyed herein.

         8. Pledgor's Failure to Pay Taxes and Other Items. If Pledgor fails to
make any payment or do any act required of it under this Agreement, then Secured
Party shall have the right, but not the obligation, upon three (3) days notice
to Pledgor, and without releasing Pledgor from any obligation under this
Agreement, to make or do the same, and to pay, purchase, contest or compromise
any lien which in Secured Party's judgment places its security interest in the
Collateral or Pledgor's title to the Collateral in jeopardy, and in exercising
any such rights, to expend whatever reasonable amounts of Secured Party in its
sole discretion may deem necessary therefor. Any amounts expended by Secured
Party pursuant to this Section 8 shall be a demand obligation owing by Pledgor,
which shall bear interest at the default rate (as defined in the Loan Documents)
from the date Secured Party expends such amount until repaid.

         9. Indemnification. Pledgor agrees to indemnify Secured Party from and
against all losses, claims, demands and liabilities of every kind and nature
arising by reason of the assignment and security interest granted and the
Collateral, excluding any of the same arising from the 


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negligence or wilful misconduct of the Secured Party, and agrees to pay all
expenses, including, without limitation, expert witness fees and attorneys fees,
incurred by Secured Party in the preservation, realization, enforcement or
exercise of any of its rights, powers or remedies hereunder.

         10. Unregistered Securities. Pledgor acknowledges that the Shares
constitute unregistered securities subject to legal restrictions upon the
transfer thereof which will render a public sale of the Shares unavailable. If,
upon an Event of Default, Secured Party exercises its right to sell the shares,
Pledgor waives all rights to public sale and agrees to the private placement of
the Shares to any qualified third-party buyer at a commercially reasonable price
therefor. Pledgor further acknowledges that the legal restrictions upon transfer
of the Shares adversely affect the marketability of the Shares and any
commercially reasonable price for the shares will include a discount from the
proportionate part of the net asset value of the issuer represented by the
Shares to reflect those restrictions upon marketability.

         11. Irrevocable Proxy. Pledgor does hereby irrevocably constitute and
appoint Secured Party and Secured Party's successors and assigns as its proxy,
with full power, in the same manner, to the same extent, and with the same
effect as if they were to do the same:

                  (a) to attend any and all meetings of the shareholders of
         AMPRO held from the date hereof, and to vote the Collateral at any such
         meeting in such manner as Secured Party shall, in its sole discretion,
         deem appropriate;

                  (b) to consent, in the sole discretion of Secured Party, to
         any and all actions by or with respect to Pledgor for which the consent
         of the Pledgor is or may be necessary or appropriate; and

                  (c) without limitation, to do all things which Pledgor can or
         could do as a shareholder of AMPRO, giving to Secured Party full power
         and substitution and revocation; provided, however, that this proxy
         shall not be exercisable by Secured Party, and Pledgor alone shall have
         the foregoing powers, so long as there is no Event of Default hereunder
         pursuant to which Secured Party has notified Pledgor that Secured Party
         is exercising its rights under this section, and provided further that
         this proxy shall terminate at such time as this Agreement is
         terminated. Pledgor hereby revokes any proxy or proxies heretofore
         given to any person or persons and agrees not to give any other proxy
         in derogation hereof until such time as this Agreement is terminated.
         Pledgor and Secured Party hereby specifically agree that the proxy
         granted hereunder shall be deemed to be valid and irrevocable until
         this Agreement shall be terminated.

         12. Attorney-in-Fact. Pledgor hereby appoints Secured Party as
Pledgor's Attorney-in-Fact (without imposing any obligations on Secured Party),
to perform all acts which Secured Party deems appropriate to perfect and
continue the security interest granted hereunder. The Power of Attorney granted
herein is coupled with an interest and is irrevocable until this Agreement is
terminated.

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         13. Miscellaneous. This Agreement, the Plan and its related documents,
and all other Loan Documents constitute the entire agreement among the parties
hereto with respect to the subject matter hereof and shall supersede all other
prior agreements, written or oral, with respect thereto.

                  (a) This Agreement shall be binding on and inure to the
         benefit of the parties hereto and their respective successors and
         assigns; provided, however, that Pledgor shall not have the right to
         assign or transfer respective rights or obligations under this
         Agreement except with the prior written consent of Secured Party.
         Secured Party, at any time with seven (7) business days prior notice to
         Pledgor, may sell, assign, grant or otherwise transfer, in whole or in
         part, the indebtedness secured hereby and Secured Party's rights,
         interest and obligations under this Agreement or the Collateral with
         the consent of the Pledgor, which will not be unreasonably withheld,
         and in such event, the transferee shall have the same rights, powers
         and authority with respect to this Agreement and the Collateral so
         transferred as are hereby given to Secured Party;

                  (b) This Agreement may be amended modified, renewed or
         extended but only by a written instrument, executed by all of the
         parties hereto in the manner of the execution of this Agreement;

                  (c) THIS AGREEMENT SHALL IN ALL RESPECTS BE GOVERNED BY, AND
         CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF ARIZONA, AND, TO
         THE EXTENT THEY PREEMPT SUCH LAWS, THE LAWS OF THE UNITED STATES;

                  (d) All parties hereto shall, from time to time, do and
         perform such other and further acts and execute and deliver any and all
         such other and further instruments as may be required or reasonably
         requested by any other party to establish, maintain and protect the
         respective rights and remedies of such other party and to carry out and
         effect the intents and purposes of this Agreement;

                  (e) All documents, Agreements, certificates and instruments
         herein required shall be in form and substance satisfactory in all
         respects to Secured Party in its sole discretion and shall be provided
         at the sole cost and expense of Pledgor;

                  (f) Pledgor's covenants shall survive the execution hereof and
         shall be performed fully and faithfully by Pledgor at all times until
         the date of repayment of the indebtedness secured hereby.


                  (g) If any term or provision of this Agreement, or the
         application thereof to any circumstance, shall be invalid, illegal or
         unenforceable to any extent, such term or provision shall not
         invalidate or render unenforceable any other term or provision of this
         Agreement, or the application of such term or provision to any other
         circumstance. To the extent 


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         permitted by law, the parties hereto hereby waive any provision of law
         that renders any term or provision hereof invalid or unenforceable in
         any respect;

                  (h) Time is of the essence of this Agreement; and

                  (i) Any notice, demand or any other instruments authorized by
         this Agreement to be served on or given shall be sufficiently served or
         given for all purposes on the earlier of: (a) when personally delivered
         to any officer of the party to whom it is addressed; (b) when sent by
         certified, registered or first class mail, postage prepaid, addressed
         to each party at its address set forth above or at such other address
         as has been furnished in writing by a party to the other in the manner
         provided in this Section; or (c) by overnight courier.

         14. Counterparts. This Agreement may be executed in any number of
counterparts, each of which, when so executed and delivered, shall be deemed to
be an original, but all such counterparts shall together constitute but one and
the same instrument.

         15. Headings. The headings of the sections and paragraphs of this
Agreement have been inserted for convenience of reference only and shall in no
way restrict or otherwise modify any of the terms or provisions hereof.

         16. Construction. All references to the singular shall include the
plural and vice versa and all references to the masculine shall include the
neuter or feminine and vice versa. This Agreement has been reviewed and
negotiated by counsel for each party and no ambiguity in this Agreement shall be
construed against any party based upon its having prepared the same.

         17. Termination. This Agreement and all of its terms and covenants,
representations and warranties shall terminate upon full satisfaction of the
indebtedness hereby secured, and, upon such termination, Secured Party shall
return to Pledgor any of the Collateral held by Secured Party pursuant to this
Agreement, and the original executed copy of this Agreement which contains an
irrevocable proxy.

         18. Acknowledgment. Pledgor acknowledges that Secured Party would not
agree to make the Loan to Pledgor without the execution, delivery and
performance of this Agreement by Pledgor. Pledgor further acknowledges that it
has received good and sufficient consideration for the execution, delivery and
performance of this Agreement.

         19. No Duty to Protect. This is a pledge and assignment of Pledgor's
rights and benefits in the Collateral without an assumption by Secured Party of
any of Pledgor's duties or obligations attendant thereto. Except for physical
safeguarding of the stock certificate(s) included in the Collateral delivered to
Secured Party, Secured Party shall have no duty to protect, insure, collect or
realize upon the Collateral or any proceeds therefrom nor shall Secured Party
have any obligations to any third party by virtue of Secured Party's possession
of the Collateral.


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         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the date first above written.

         PLEDGOR:                   AMERICAN PROFESSIONAL HOLDINGS, INC.
                                    a Utah corporation

                                    By:_________________________________
                                    Name:_______________________________
                                    Title:______________________________

         SECURED PARTY:             ELK MEADOWS INVESTMENTS, L.L.C.,
                                    a Colorado limited liability company

                                    By:_________________________________
                                       David Kremser, Managing Member


                                    ___________________________________
                                    David Kremser


                                    ___________________________________
                                    Bernice Kremser by her attorney-in-fact,
                                    David Kremser


                                    ___________________________________
                                    Holly Kremser by her attorney-in-fact,
                                    David Kremser


                                    ___________________________________
                                    Michael Kremser by his attorney-in-fact,
                                    David Kremser


                                    ___________________________________
                                    Stanley Kremser by his attorney-in-fact,
                                    David Kremser


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                             IRREVOCABLE STOCK POWER

                             Certificate(s) No(s). 

         FOR VALUE RECEIVED, AMERICAN PROFESSIONAL HOLDINGS, INC., a Utah
corporation ("Pledgor"), hereby assigns and transfers to David Kremser, Bernice
Kremser, Holly Kremser, Michael Kremser, Stanley Kremser and ELK MEADOWS
INVESTMENTS, L.L.C. (collectively the "Secured Party"), pursuant to the Stock
Pledge Agreement, dated as of January 31, 1999 (the "Stock Pledge Agreement"),
between the Pledgor and Secured Party, _____ shares of common stock of AMPRO
MEDICAL SERVICES, INC., a Texas corporation (the "Common Shares"), of the
Secured Party, as security for the Loan (as defined in the Pledge Agreement).

         The undersigned does hereby irrevocably constitute and appoint David
Kremser as its attorney-in-fact to transfer the said stock or bond(s), as the
case may be, on the books of AMRPO MEDICAL SERVICES, INC. with full power of
substitution in the premises.

Dated: _______________, 1999



                                    AMERICAN PROFESSIONAL HOLDINGS, INC.
                                    a Utah corporation


                                    By:_________________________________
                                    Name:_______________________________
                                    Title:______________________________