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                                                                EXHIBIT 10.10(h)



              AMENDMENT NUMBER ONE TO LOAN AND SECURITY AGREEMENT


        This Amendment Number One to Loan and Security Agreement ("Amendment")
is entered into on March 23, 1999 and effective as of December 1, 1998, by and
among FOOTHILL CAPITAL CORPORATION, a California corporation ("Foothill") on the
one hand, and INTERNATIONAL REMOTE IMAGING SYSTEMS, INC., Delaware corporation
("IRIS"), PERCEPTIVE SCIENTIFIC INSTRUMENTS, LLC, a Delaware limited liability
company ("New PSI"), and STATSPIN, INC., a Massachusetts corporation
("Statspin") ("Borrowers") on the other hand, in light of the following:

               FACT ONE: IRIS, Statspin, and Perceptive Scientific Instruments,
Inc. ("Old PSI") and Foothill have previously entered into that certain Loan and
Security Agreement, dated as of May 5, 1998 (the "Agreement").

               FACT TWO: Old PSI has been merged into a New PSI. New PSI is the
surviving entity and pursuant to the terms of this Amendment will become a
Borrower under the Agreement.

               FACT THREE: Borrowers and Foothill desire to amend the Agreement
as provided for and on the conditions herein.

               NOW, THEREFORE, Borrower and Foothill hereby amend and supplement
the Agreement as follows:

               1. DEFINITIONS. All initially capitalized terms used in this
Amendment shall have the meanings given to them in the Agreement unless
specifically defined herein.

               2.     AMENDMENTS.

                      (a) The introductory paragraph on page one of the 
Agreement is hereby amended by deleting the same in its entirety and replacing
it with the following:

"THIS LOAN AND SECURITY AGREEMENT (THIS "AGREEMENT"), is entered into as of May
5, 1998, among FOOTHILL CAPITAL CORPORATION, a California corporation
("Foothill"), with a place of business located at 11111 Santa Monica Boulevard,
Suite 1500, Los Angeles, California 90025-3333, on the one hand, and
INTERNATIONAL REMOTE IMAGING SYSTEMS, INC., a Delaware corporation ("IRIS"),
with its chief executive office located at 9162 Eton Avenue, Chatsworth,
California 91311, PERCEPTIVE SCIENTIFIC INSTRUMENTS, LLC, a Delaware limited
liability company ("PSI"), with its chief executive office at 2525 South Shore
Boulevard, No. 100, League City, Texas 77573 and STATSPIN, INC., a Massachusetts
corporation ("StatSpin"), with its chief executive office located at 85 Morse
Street, Norwood, Massachusetts 02062, on the other hand."



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                      (b) Section 7.3 of the Agreement is hereby amended by
inserting the following at the end of such section:

                             "Provided, however that Foothill agrees to allow 
the merger of Perceptive Scientific Instruments, Inc. into PSI."

               3. REPRESENTATIONS AND WARRANTIES. Borrowers hereby affirm to
Foothill that all of Borrowers' representations and warranties set forth in the
Agreement are true, complete and accurate in all respects as of the date hereof,
except as identified in Schedule 3.1.

               4. NO DEFAULTS. Borrowers hereby affirm to Foothill that no Event
of Default has occurred and is continuing as of the date hereof, except as
identified in Schedule 4.1 for which waivers have been requested.

               5. CONDITION PRECEDENT. The effectiveness of this Amendment is
expressly conditioned upon the following:

               (a)  Receipt by Foothill of an executed copy of the
                    following:

                    (i) An executed copy of this Amendment;

                    (ii) An executed copy of the Amendment to Copyright Security
                    Agreement;

                    (iii) An executed copy of the Amendment to Intellectual
                    Property Security Agreement;


                    (iv) An executed copy of the Amendment Number One to
                    Security Agreement-Stock Pledge; and
                             

                    (v) Signed financing statements for the states of Texas,
                    Massachusetts, and California reflecting New PSI as Debtor
                    and Foothill as Secured Party.

               6. COSTS AND EXPENSES. Borrowers shall pay to Foothill all of
Foothill's out-of-pocket costs and expenses (including, without limitation, the
fees and expenses of its counsel, which counsel may include any local counsel
deemed necessary, search fees, filing and recording fees, documentation fees,
appraisal fees, travel expenses, and other fees) arising in connection with the
preparation, execution, and delivery of this Amendment and all related
documents.

               7. LIMITED EFFECT. In the event of a conflict between the terms
and provisions of this Amendment and the terms and provisions of the Agreement,
the terms and provisions of this Amendment shall govern. In all other respects,
the Agreement, as amended and supplemented hereby, shall remain in full force
and effect.

               8. COUNTERPARTS; EFFECTIVENESS. This Amendment may be executed in
any number of counterparts and by different parties on separate counterparts,
each of which when so executed and delivered shall be deemed to be an original.
All such 



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counterparts, taken together, shall constitute but one and the same Amendment.
This Amendment shall become effective upon the execution of a counterpart of
this Amendment by each of the parties hereto.

               IN WITNESS WHEREOF, the parties hereto have executed this
Amendment as of the date first set forth above.


                       FOOTHILL CAPITAL CORPORATION,                       
                       a California corporation                            
                                                                           
                                                                           
                       By: /s/ STEPHEN SCHWARTZ                            
                          -------------------------------------------------
                       Title: Assistant Vice President                     
                             ----------------------------------------------
                                                                           
                                                                           
                       INTERNATIONAL REMOTE IMAGING SYSTEMS, INC.,         
                       a Delaware corporation                              
                                                                           
                                                                           
                       By: /s/ MARTIN S. McDERMOT                          
                          -------------------------------------------------
                       Title: Vice President - Finance and Administration  
                             ----------------------------------------------
                              and Chief Financial Officer                  
                             ----------------------------------------------
                                                                           
                                                                           
                       STATSPIN, INC.,                                     
                       a Massachusetts corporation                         
                                                                           
                                                                           
                       By: /s/ MARTIN S. McDERMOT                          
                          -------------------------------------------------
                       Title: Vice President and Chief Financial Officer   
                             ----------------------------------------------
                                                                           
                                                                           
                       PERCEPTIVE SCIENTIFIC INSTRUMENTS, LLC,             
                       a Delaware limited liability company                

                       By:     Statspin, Inc., a Massachusetts corporation,
                               Its sole Member


                               By: /s/ MARTIN S. McDERMOT
                                  ----------------------------------------------
                               Title: Vice President and Chief Financial Officer
                                      ------------------------------------------



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