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                                                                   EXHIBIT 10.13

                              EMPLOYMENT AGREEMENT

        THIS AGREEMENT ("Agreement"), dated as of March 1, 1998, is made and
entered into by and between COHR, INC., a Delaware corporation ("Company"), and
Aviva Truesdell, an individual ("Executive").

                                     RECITAL

        Employee is a key executive of the Company and an integral part of its
management. This Agreement is being entered into in connection with the
Company's continued employment of Executive.

                                    AGREEMENT

        NOW, THEREFORE, Company and Executive agree as follows:

        1. This Agreement shall be in effect from the date of execution to and
including February 28, 1999, unless renewed or terminated earlier as provided
herein. The term of this Agreement will automatically extend for an additional
one (1) year period, unless a written notice of non-renewal is given by either
party no less than thirty (30) days prior to the expiration date provided in the
preceding sentence. Executive is and will continue to be employed by Company in
the position held by Executive as of the effective date of this Agreement and
pursuant to its terms. Executive's job description as of the effective date
hereof is attached hereto as Exhibit A. During her employment hereunder,
Executive shall continue to devote all of her attention and business during
normal business hours to the performance of this Agreement and shall, without
the Company's prior written consent in each instance, refrain from rendering
services of any kind to others for compensation or which would materially
interfere with the performance with her duties under this Agreement.


        2.

                a. Company shall pay a base salary to Executive for the term
                hereof at the minimum rate of One Hundred Forty Four Thousand
                Dollars ($144,000) per year, payable in semi-monthly
                installments. In addition to her base salary, Executive may be
                eligible, in accordance with Company policy and in the
                discretion of the board of directors, to be considered for an
                annual bonus based on such criteria as may be established by the
                compensation committee.

                b. All compensation provided pursuant to this Paragraph 2 shall
                be subject to customary income tax withholding and such other
                employee deductions as are required by law with respect to
                compensation paid to an employee.

                c. In addition to the base compensation and bonus provided in
                this Agreement, Executive shall throughout the term hereof
                (prior to death) be entitled to and shall receive all other
                benefits generally available to other executives of the Company
                of the same level and length of service as Executive. Executive
                shall be entitled to paid vacation in accordance with the policy
                of the Company generally applicable to other executives of
                Company with similar length of service.


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        3. As a material part of the consideration for entering into this
Agreement, Company and Executive have agreed that concurrently with the payment
to Executive of any compensation upon termination of employment as provided
herein, Company and Executive shall execute and deliver to each other a complete
mutual release and discharge of any and all rights, claims, actions and right to
arbitration which Executive or the Company, their respective successors and
assigns, have against each other arising out of Executive's employment or the
termination of Executive's employment; provided however that the Company is not
releasing, and shall not release, Executive from any rights, claims or actions
arising from any act or omission which would have constituted grounds for
termination of this Agreement if then known by the Company.

        4. Except as provided in Paragraph 5 below, in the event of the
occurrence of one of the following prior to February 28, 1999 - i.e., either
(a), (b) or (c) below:

               a. Executive is given written notice of the termination of this
Agreement and Executive's employment, other than for cause (as defined herein
below);

               b. Executive is permanently relocated without her consent to
outside of the greater Los Angeles area and Executive resigns within three (3)
months of notification of such relocation; or

               c. Executive's responsibilities and salary are materially reduced
and Executive resigns within three (3) months of such reduction,

then Company shall, subject to Paragraphs 3 and 5 hereof, for the months
remaining under this Agreement following such termination or resignation, BUT IN
NO EVENT FOR LESS THAN TWELVE (12) MONTHS following the effective date of such
termination or resignation, (i) pay to Executive each month an amount equal to
one-twelfth (1/12) of Executive's then annual base salary, except that such
payment shall be subject to Federal and State Income Tax withholding, social
security and SDI withholding, and such other employee deductions as are required
by Federal, State or local law or authorized by the Executive in good faith, and
(ii) continue, at the expense of Company, health benefit coverage, at the same
coverage level in effect at the time of such termination or resignation,
provided, to the extent that Executive shall receive or be entitled to any
health benefit coverage from any subsequent employment, the health benefit
coverage provided at Company's expense shall be terminated. The amount of any
continued payment of base salary provided for in this paragraph shall not be
reduced, offset or subject to recovery by reason of any compensation earned by
Executive with a subsequent employer.

        For purposes of Paragraphs 4 and 5 hereof, a termination "for cause"
occurs if Executive is terminated for any of the following reasons: (i) theft,
dishonesty, or falsification of any employment or Company records; (ii) knowing
and improper disclosure of Company's confidential or proprietary information;
(iii) any act or failure to act by Executive which has a material detrimental
effect on Company's reputation or business, is beyond the course and scope of
the Executive's duties, is not in the best interests of the Company or is a
breach of the Executive's fiduciary duties to Company; (iv) Executive commits an
act or becomes involved in any situation or occurrence degrading to Executive in
society or bringing Executive into public disrepute, contempt, scandal or
ridicule; (v) habitual neglect of duties or wanton negligence by 


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Executive in the performance of duties; (vi) violation of (A) a material Company
policy or procedure or (B) any law or regulation (except for minor offenses
unrelated to work or qualifications for work, such as traffic or parking
violations or like matters); (vii) material wrongdoing or misconduct; or (viii)
any material breach of this Agreement which breach is not cured within thirty
(30) days following written notice of such breach from Company.

        In addition, in the event Executive in accordance with Company policy is
entitled at the time of her termination to the use of a Company leased
automobile, Executive shall retain the right to use such automobile for one
month after the date of termination of this Agreement, provided Executive shall
be responsible for any damage to said automobile occurring during said one month
period of time which is not covered by insurance. At the end of such one month
period, Executive shall return such leased automobile to Company at Company's
principal executive offices.

        5. Neither Company nor its successor in interest shall be required to
make any payments under Paragraph 4 above in the event Executive is terminated
for cause, retires, or voluntarily resigns. Such payments shall be made to
Executive's estate in accordance with Paragraph 4 in the event Executive dies or
to Executive in the event Executive becomes disabled as disability is defined in
the next sentence. For the purposes of this Agreement, "disability" shall mean
if at the end of any calendar month, Executive is and has, for three (3) full
consecutive months out of any twelve (12) month period continuously been unable
due to mental of physical illness or injury to perform her duties under this
Agreement in her normal or regular manner.

        6. Except as required for the purposes of proxy disclosure, NASDAQ rules
or applicable laws or regulations, the parties each represent and agree that
they will keep the terms, contents and existence of this Agreement completely
confidential, and will not hereafter disclose any information concerning this
Agreement, including any negotiations leading to this Agreement, to anyone
except as required by law or to individuals who reasonably must be informed of
its terms and who will be advised of and bound by this confidentiality clause.
Notwithstanding the foregoing, either party may disclose this Agreement or its
terms or contents in any arbitration pursuant to Paragraph 9 hereof. Any failure
by any party, their attorneys, agents or representatives to maintain the
confidentiality of the negotiations leading to this Agreement or the fact of, or
the terms of this Agreement shall constitute a material breach of this
Agreement.

        7. Fiduciary Duties. Executive acknowledges that she is a fiduciary of
the Company and as such is subject to duties to the Company, its Board of
Directors and Stockholders, including but not limited to the obligation to
discharge her duties (1) in good faith, (2) with the care of an ordinarily
prudent person in a like position would exercise under similar circumstances,
and (3) in a manner she reasonably believes to be in the best interests of the
corporation. Consistent with this fiduciary duty, and not by way of limitation
in this regard, Executive agrees to cooperate with and/or assist the Company's
Board of Directors and its consultants or advisors in exploring, preparing for
or implementing such strategic alternatives (including assisting with a possible
sale of all or a portion of the Company) as the Board may determine to pursue.


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        8. Confidential Information. Executive and Company agree that
Executive's employment with Company creates a relationship of confidence and
trust between the Company and Executive with respect to any information: (a)
applicable to the business of the Company, or (b) applicable to the business of
any client or customer of the Company, which may be made known to Executive by
the Company or by any client of the Company, or learned by Executive in such
context during the period of Executive's employment. All of such information has
commercial value in the business in which Company is engaged and is hereinafter
referred to as "Proprietary Information." Executive and the Company agree that
all Proprietary Information is the sole property of the Company, its assigns and
its customers; the Company, its assigns and its customers shall be the sole
owner of all patents, copyrights, trade secrets and other rights in connection
therewith. Executive hereby assigns to the Company any rights she may have or
acquire in such Proprietary Information. At all times, both during Executive's
employment by the Company and after its termination, Executive will keep in
confidence and trust all Proprietary Information and will not use or disclose
any Proprietary Information or anything directly relating to it without the
written consent of the Company, except as may be necessary in the ordinary
course of performing Executive's duties as an employee of the Company.
Notwithstanding the foregoing, it is understood that at all such times,
Executive is free to use information which is generally known in the trade
industry not as a result of a breach of this Agreement and Executive's own
skill, knowledge, know-how and experience to whatever extent and whatever way
Executive may wish.

        9. Non Compete. Executive acknowledges that as an executive of the
Company, she has been instrumental in the business of the Company and its
success. Accordingly, Executive agrees that during the term of her employment
hereunder she will not, directly or indirectly, within the following California
counties: Alameda, Fresno, Los Angeles, Orange, Riverside, San Bernardino,
Ventura, Santa Barbara and San Joaquin, or any other location in the State of
California or the United States where the Company is transacting business either
during the term of this Agreement or at the time of the termination of
Executive's employment hereunder, as the case may be, engage or participate or
make financial investments in or become employed by or render advisory or other
services to or for any person, firm or corporation or, in connection with any
business activity other than that of the Company and its subsidiary or
affiliated companies, directly or indirectly in competition with any of the
business operation or activities of the Company and its subsidiary or affiliated
companies, whether such companies are presently existing or hereafter acquired
or formed. Nothing herein contained however, shall restrict Executive from
making any investments in any company whose stock is listed on the National
Securities Exchange or actively traded in the over-the-counter market, so long
as such investment does not give her the right to control or influence the
policy decisions of any such business or enterprise which is or might be
directly or indirectly in competition with any of the business operations or
activities of the Company or any of its subsidiary of affiliated companies.

        10. For a period of one (1) year from and after the termination or
expiration of Executive's employment with Company, whether pursuant to the terms
of this Agreement or otherwise, Executive shall not:

                a. Directly or indirectly solicit any executive or managerial
                employee of Company to discontinue working for or representing
                Company for the purpose of 


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                working for or representing any subsequent employer of Executive
                which is a competitor of Company; or b. Authorize or knowingly
                approve the taking of such actions by other persons on behalf of
                any such competitor or assist any such person, firm or
                corporation in taking such action.

        11. Executive acknowledges that she has been advised to seek an attorney
for advice regarding the effect of this Agreement prior to signing it.

        12. If any claim is brought under this Agreement, or any dispute of any
nature whatsoever arises regarding the termination of this Agreement or the
termination of Executive's employment, the Company and Executive agree that such
claim or dispute shall be resolved in an arbitration proceeding conducted under
the auspices of the American Arbitration Association, Los Angeles, California
and in accordance with its Employment Dispute Resolution rules. The arbitrator
agreed to under such rules shall be empowered to resolve the dispute through
consideration of the facts, the terms of this Agreement, and any statute, law,
regulation, or defense asserted by either party, and the arbitrator's decision
shall be final and binding. If so authorized by the arbitrator, the prevailing
party shall be entitled to recover from the non-prevailing party reasonable
expenses, including without limitation reasonable attorneys' fees.

        13. If any of the above provisions are found null, void, or inoperative,
for any reason, the remaining provisions will remain in full force and effect.

        14. This Agreement may be executed by facsimile and in identical
counterparts. The Agreement will be binding on the parties once it has been
fully executed. Thereafter, the parties will exchange hard copies and all the
counterparts together shall constitute a single agreement, and it shall not be
necessary to introduce more than one fully executed counterpart to enforce this
Agreement.

        15. Any notice to the Company required or permitted hereunder shall be
given in writing to the secretary of Company either by personal service or by
registered mail postage prepaid addressed to Company at its then principal place
of business. Any such notice to Executive shall be given in like manner and mail
shall be addressed to the Executive at her home address then shown in the files
of Company.

        16. This Agreement may be extended for an additional period and subject
to additional or different terms by written agreement of the parties.

                          [SIGNATURES APPEAR ON PAGE 6]


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        IN WITNESS WHEREOF, the undersigned have executed this Employment
Agreement as of the date above written.

"Company"                                         "Executive"

COHR, INC.



By:_______________________________                ______________________________
        Stephen W. Gamble, Interim CEO            Aviva Truesdell


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                                    EXHIBIT A

                       [Attach Executive Job Description]


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