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                                                                     Exhibit 4.6


THE SECURITIES REPRESENTED BY THIS WARRANT HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933, AS AMENDED, OR APPLICABLE STATE SECURITIES LAWS. THE
SECURITIES HAVE BEEN ACQUIRED FOR INVESTMENT AND MAY NOT BE OFFERED FOR SALE,
SOLD, TRANSFERRED OR ASSIGNED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION
STATEMENT FOR THE SECURITIES UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR
APPLICABLE STATE SECURITIES LAWS, OR AN OPINION OF COUNSEL IN FORM, SUBSTANCE
AND SCOPE REASONABLY ACCEPTABLE TO THE ISSUER THAT REGISTRATION IS NOT REQUIRED
UNDER SAID ACT OR APPLICABLE STATE SECURITIES LAWS OR UNLESS SOLD PURSUANT TO
RULE 144 UNDER SAID ACT. ANY SUCH OFFER, SALE, ASSIGNMENT OR TRANSFER MUST ALSO
COMPLY WITH THE APPLICABLE STATE SECURITIES LAWS.


                          ALLIANCE MEDICAL CORPORATION

                             STOCK PURCHASE WARRANT


Date of Issuance:  July 19, 1999                  Number of Shares _____________


                  For value received, Alliance Medical Corporation, a Delaware
corporation (the "Company") hereby grants to _____________ or its registered
assigns (the "Registered Holder") the right to purchase from the Company a
number of shares of the Company's Common Stock (the "Common Stock") at a price
per share equal to $1.10 (the "Exercise Price").

                  This Warrant is subject to the following provisions:

                  Section 1.  Exercise of Warrant.

                  1A. Exercise Period. The Registered Holder may exercise, in
whole or in part, the purchase rights represented by this Warrant at any time
and from time to time after the Date of Issuance until the fifth anniversary of
the date hereof (the "Exercise Period").

                  1B. Exercise Procedure.

                  (i) This Warrant shall be deemed to have been exercised when
the Company has received all of the following items (the "Exercise Time"):

                  (a) a completed Exercise Agreement, as described in Section 1C
         below, executed by the Person exercising all or part of the purchase
         rights represented by this Warrant (the "Purchaser");
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                  (b) this Warrant;

                  (c) if this Warrant is not registered in the name of the
         Purchaser, an Assignment or Assignments in the form set forth in
         Exhibit II hereto evidencing the assignment of this Warrant to the
         Purchaser, in which case the Registered Holder shall have complied with
         the provisions set forth in Section 7 hereof; and

                  (d) a check payable to the Company in an amount equal to the
         product of the Exercise Price multiplied by the number of shares of
         Common Stock being purchased upon such exercise (the "Aggregate
         Exercise Price").

                   (ii) A certificate for shares of Common Stock purchased upon
exercise of this Warrant shall be delivered by the Company to the Purchaser
within ten business days after the date of the Exercise Time. Unless this
Warrant has expired or all of the purchase rights represented hereby have been
exercised, the Company shall prepare a new Warrant, substantially identical
hereto, representing the rights formerly represented by this Warrant which have
not expired or been exercised and shall, within such ten-day period, deliver
such new Warrant to the Person designated for delivery in the Exercise
Agreement.

                   (iii) The Common Stock issuable upon the exercise of this
Warrant shall be deemed to have been issued to the Purchaser at the Exercise
Time, and the Purchaser shall be deemed for all purposes to have become the
record holder of such Common Stock at the Exercise Time.

                   (iv) The issuance of certificates for shares of Common Stock
upon exercise of this Warrant shall be made without charge to the Registered
Holder or the Purchaser for any issuance tax in respect thereof or other cost
incurred by the Company in connection with such exercise and the related
issuance of shares of Common Stock. Each share of Common Stock issuable upon
exercise of this Warrant shall, upon payment of the Exercise Price therefor, be
fully paid and nonassessable and free from all liens and charges with respect to
the issuance thereof.

                   (v) The Company shall not close its books against the
transfer of this Warrant or of any share of Common Stock issued or issuable upon
the exercise of this Warrant in any manner which interferes with the timely
exercise of this Warrant, except as required in order to comply with applicable
federal and state securities laws. The Company shall from time to time take all
such action as may be necessary to assure that the par value per share of the
unissued Common Stock acquirable upon exercise of this Warrant is at all times
equal to or less than the Exercise Price then in effect.

                   (vi) The Company shall assist and cooperate with any
Registered Holder or Purchaser required to make any governmental filings or
obtain any governmental approvals prior to or in connection with any exercise of
this Warrant (including, without limitation, making any filings required to be
made by the Company), except that this subsection (vi) will not require the
Company to register the sale of the Common Stock underlying this Warrant under
any federal or state securities laws.

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                  (vii) Notwithstanding any other provision hereof, if an
exercise of any portion of this Warrant is to be made in connection with a
registered public offering or the sale of the Company, the exercise of any
portion of this Warrant may, at the election of the holder hereof, be
conditioned upon the consummation of the public offering or sale of the Company
in which case such exercise shall not be deemed to be effective until the
consummation of such transaction.

                  (viii) The Company shall at all times reserve and keep
available out of its authorized but unissued shares of Common Stock solely for
the purpose of issuance upon the exercise of the Warrants, such number of shares
of Common Stock issuable upon the exercise of all outstanding Warrants. All
shares of Common Stock which are so issuable shall, when issued, be duly and
validly issued, fully paid and nonassessable and free from all taxes, liens and
charges. The Company shall take all such actions as may be necessary to assure
that all such shares of Common Stock may be so issued without violation of any
applicable law or governmental regulation or any requirements of any domestic
securities exchange upon which shares of Common Stock may be listed (except for
official notice of issuance which shall be immediately delivered by the Company
upon each such issuance). The Company shall not take any action which would
cause the number of authorized but unissued shares of Common Stock to be less
than the number of such shares required to be reserved hereunder for issuance
upon exercise of the Warrant.

                  (ix) If the shares of Common Stock issuable by reason of
exercise of this Warrant are convertible into or exchangeable for any other
stock or securities of the Company, the Company shall, at the exercising
holder's option and upon surrender of this Warrant by such holder as provided
above together with any notice, statement or payment required to effect such
conversion or exchange of Common Stock, deliver to such holder (or as otherwise
specified by such holder) a certificate or certificates representing the stock
or securities into which the shares of Common Stock issuable by reason of such
conversion are convertible or exchangeable, registered in such name or names and
in such denomination or denominations as such holder has specified.

                  1C. Exercise Agreement. Upon any exercise of this Warrant, the
Exercise Agreement shall be substantially in the form set forth in Exhibit I
hereto, except that if the shares of Common Stock are not to be issued in the
name of the Person in whose name this Warrant is registered, the Exercise
Agreement shall also state the name of the Person to whom the certificates for
the shares of Common Stock are to be issued, and if the number of shares of
Common Stock to be issued does not include all the shares of Common Stock
purchasable hereunder, it shall also state the name of the Person to whom a new
Warrant for the unexercised portion of the rights hereunder is to be delivered.
Such Exercise Agreement shall be dated the actual date of execution thereof.


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                  Section 2.

                  2A. Subdivision or Combination of Common Stock. If the Company
at any time subdivides (by any stock split, stock dividend, recapitalization or
otherwise) one or more classes of its outstanding shares of Common Stock into a
greater number of shares, the Exercise Price in effect immediately prior to such
subdivision shall be proportionately reduced and the number of shares of Common
Stock obtainable upon exercise of this Warrant shall be proportionately
increased. If the Company at any time combines (by reverse stock split or
otherwise) one or more classes of its outstanding shares of Common Stock into a
smaller number of shares, the Exercise Price in effect immediately prior to such
combination shall be proportionately increased and the number of shares of
Common Stock obtainable upon exercise of this Warrant shall be proportionately
decreased.

                  2B. Reorganization, Reclassification, Consolidation, Merger or
Sale. Any recapitalization, reorganization, reclassification, consolidation,
merger, sale of all or substantially all of the Company's assets or other
transaction, which in each case is effected in such a way that the holders of
Common Stock are entitled to receive (either directly or upon subsequent
liquidation) stock, securities or assets with respect to or in exchange for
Common Stock is referred to herein as "Organic Change." Prior to the
consummation of any Organic Change, the Company shall make appropriate provision
(in form and substance satisfactory to the Registered Holders of the Warrants
representing a majority of the Common Stock obtainable upon exercise of all
Warrants then outstanding) to insure that each of the Registered Holders of the
Warrants shall thereafter have the right to acquire and receive, in lieu of or
addition to (as the case may be) the shares of Common Stock immediately
theretofore acquirable and receivable upon the exercise of such holder's
Warrant, such shares of stock, securities or assets as may be issued or payable
with respect to or in exchange for the number of shares of Common Stock
immediately theretofore acquirable and receivable upon exercise of such holder's
Warrant had such Organic Change not taken place. In any such case, the Company
shall make appropriate provision (in form and substance satisfactory to the
Registered Holders of the Warrants representing a majority of the Common Stock
obtainable upon exercise of all Warrants then outstanding) with respect to such
holders' rights and interests to insure that the provisions of this Section 2
and Sections 3 and 4 hereof shall thereafter be applicable to the Warrants
(including, in the case of any such consolidation, merger or sale in which the
successor entity or purchasing entity is other than the Company, an immediate
adjustment of the Exercise Price to the value for the Common Stock reflected by
the terms of such consolidation, merger or sale, and a corresponding immediate
adjustment in the number of shares of Common Stock acquirable and receivable
upon exercise of the Warrants). The Company shall not effect any such
consolidation, merger or sale, unless prior to the consummation thereof, the
successor entity (if other than the Company) resulting from consolidation or
merger or the entity purchasing such assets assumes by written instrument (in
form and substance satisfactory to the Registered Holders of Warrants
representing a majority of the Common Stock obtainable upon exercise of all of
the Warrants then outstanding), the obligation to deliver to each such holder
such shares of stock, securities or assets as, in accordance with the foregoing
provisions, such holder may be entitled to acquire.


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                  2C. Notices.

                    (i) Immediately upon any adjustment of the Exercise Price,
the Company shall give written notice thereof to the Registered Holder, setting
forth in reasonable detail and certifying the calculation of such adjustment.

                    (ii) The Company shall give written notice to the Registered
Holder at least 20 days prior to the date on which the Company closes its books
or takes a record (A) with respect to any pro rata subscription offer to holders
of Common Stock or (B) for determining rights to vote with respect to any
Organic Change, dissolution or liquidation.

                    (iii) The Company shall also give written notice to the
Registered Holders at least 20 days prior to the date on which any Organic
Change, dissolution or liquidation shall take place.

                  Section 3. Liquidating Dividends. If at any time on or after
the date this Warrant becomes exercisable the Company declares or pays a
dividend upon the Common Stock payable otherwise than in cash out of earnings or
earned surplus (determined in accordance with generally accepted accounting
principles, consistently applied) except for a stock dividend payable in shares
of Common Stock (a "Liquidating Dividend"), then the Company shall pay to the
Registered Holder of this Warrant at the time of payment thereof the Liquidating
Dividend which would have been paid to such Registered Holder on the Common
Stock had this Warrant been fully exercised immediately prior to the date on
which a record is taken for such Liquidating Dividend, or, if no record is
taken, the date as of which the record holders of Common Stock entitled to such
dividends are to be determined; provided that if the Liquidating Dividends
consist of voting securities, the Company shall make available to the Registered
Holder of this Warrant, at such holder's request, Liquidating Dividends
consisting of securities (except as otherwise required by law) which are
otherwise identical to the Liquidating Dividends consisting of voting
securities.

                  Section 4. Purchase Rights. If at any time on or after the
date this Warrant becomes exercisable the Company grants, issues or sells any
Options, Convertible Securities or rights to purchase stock, warrants,
securities or other property pro rata to the record holders of any class of
Common Stock (the "Purchase Rights"), then the Registered Holder of this Warrant
shall be entitled to acquire, upon the terms applicable to such Purchase Rights,
the aggregate Purchase Rights which such holder could have acquired if such
holder had held the number of shares of Common Stock acquirable upon complete
exercise of this Warrant immediately before the date on which a record is taken
for the grant, issuance or sale of such Purchase Rights, or, if no such record
is taken, the date as of which the record holders of Common Stock are to be
determined for the grant, issue or sale of such Purchase Rights; provided that
if the Purchase Rights involve voting securities, the Company shall make
available to the Registered Holder of this Warrant, at such holder's request,
Purchase Rights involving securities (except as otherwise required by law) which
are otherwise identical to the Purchase Rights involving voting securities.

                  Section 5. Definitions. The following terms have meanings set
forth below:

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                  "Common Stock" means the Company's Common Stock, par value
$0.001 per share and any capital stock of any class of the Company hereafter
authorized which is not limited to a fixed sum or percentage of par or stated
value in respect to the rights of the holders thereof to participate in
dividends or in the distribution of assets upon any liquidation, dissolution or
winding up of the Company.

                  "Convertible Securities" means any stock or securities
(directly or indirectly) convertible into or exchangeable for Common Stock.

                  "Options" means any rights or options to subscribe for or
purchase Common Stock or Convertible Securities.

                  "Person" means an individual, a partnership, a joint venture,
a corporation, a limited liability company, a trust, an unincorporated
organization and a government or any department or agency thereof.

                  Section 6. Piggyback Registration Rights. Whenever the Company
proposes to register any of its equity securities under the Securities Act of
1933 (other than pursuant to a registration statement on Form S-4 or S-8 or
similar form) and the registration form to be used may be used for the
registration of the Shares underlying this Warrant (a "Piggyback Registration"),
the Company shall give prompt written notice to the holders of this Warrant or
the Shares underlying this Warrant of its intention to effect such a
registration and shall include in such registration all shares of Common Stock
underlying this Warrant with respect to which the Company has received written
requests for inclusion therein within 20 days after the receipt of the Company"s
notice. These piggyback registration rights shall be subordinate in all respects
to the registration rights granted to the Purchasers pursuant to that certain
Registration Agreement dated as of July 19, 1999, by and among the Company and
the Persons listed on the signature pages thereto (the "Registration Agreement")
and will be subject in all respects to the terms and conditions set forth in the
Registration Agreement regarding piggyback registration rights.

                  Section 7. No Voting Rights; Limitations of Liability. This
Warrant shall not entitle the holder hereof to any voting rights or other rights
as a stockholder of the Company. No provision hereof, in the absence of
affirmative action by the Registered Holder to purchase Common Stock, and no
enumeration herein of the rights or privileges of the Registered Holder shall
give rise to any liability of such holder for the Exercise Price of Common Stock
acquirable by exercise hereof or as a stockholder of the Company.

                  Section 8. Warrant Transferable. Subject to the transfer
conditions referred to in the legend endorsed hereon, this Warrant and all
rights hereunder are transferable, in whole or in part, without charge to the
Registered Holder, upon surrender of this Warrant with a properly executed
Assignment (in the form of Exhibit II hereto) at the principal office of the
Company, subject to compliance with applicable federal and state securities
laws.

                  Section 9. Warrant Exchangeable for Different Denominations.
This Warrant is exchangeable, upon the surrender hereof by the Registered Holder
at the principal office of the

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Company, for new Warrants of like tenor representing in the aggregate the
purchase rights hereunder, and each of such new Warrants shall represent such
portion of such rights as is designated by the Registered Holder at the time of
such surrender; provided that, as long as any Subject Shares remain outstanding,
this Warrant shall only be exchangeable in connection with the exchange of the
certificate representing such Subject Shares pursuant to the Company's
Certificate of Incorporation. The date the Company initially issues this Warrant
shall be deemed to be the "Date of Issuance" hereof regardless of the number of
times new certificates representing the unexpired and unexercised rights
formerly represented by this Warrant shall be issued. All Warrants representing
portions of the rights hereunder are referred to herein as the "Warrants."

                  Section 10. Replacement. Upon receipt of evidence reasonably
satisfactory to the Company (an affidavit of the Registered Holder shall be
satisfactory) of the ownership and the loss, theft, destruction or mutilation of
any certificate evidencing this Warrant, and in the case of any such loss, theft
or destruction, upon receipt of indemnity reasonably satisfactory to the Company
(provided that if the holder is a financial institution or other institutional
investor its own agreement shall be satisfactory), or, in the case of any such
mutilation upon surrender of such certificate, the Company shall (at its
expense) execute and deliver in lieu of such certificate a new certificate of
like kind representing the same rights represented by such lost, stolen,
destroyed or mutilated certificate and dated the date of such lost, stolen,
destroyed or mutilated certificate.

                  Section 11. Notices. Except as otherwise expressly provided
herein, all notices referred to in this Warrant shall be in writing and shall be
delivered personally, sent by reputable overnight courier service (charges
prepaid) or sent by registered or certified mail, return receipt requested,
postage prepaid and shall be deemed to have been given when received (if hand
delivered) or five days after delivered, sent or deposited in the U.S. Mail or
by overnight courier (i) to the Company, at its principal executive offices and
(ii) to the Registered Holder of this Warrant, at such holder's address as it
appears in the records of the Company (unless otherwise indicated by any such
holder).

                  Section 12. Amendment and Waiver. Except as otherwise provided
herein, the provisions of the Warrants may be amended and the Company may take
any action herein prohibited, or omit to perform any act herein required to be
performed by it, only if the Company has obtained the written consent of the
Registered Holders of Warrants representing a majority of the shares of Common
Stock obtainable upon exercise of the Warrants; provided that no such action may
change the Exercise Price of the Warrants or the number of shares or class of
stock obtainable upon exercise of each Warrant without the written consent of
Registered Holders beneficially owning a majority of the subject Shares.

                  Section 13. Descriptive Headings; Governing Law. The
descriptive headings of the several Sections and paragraphs of this Warrant are
inserted for convenience only and do not constitute a part of this Warrant. The
corporation laws of the State of Arizona shall govern all issues concerning the
relative rights of the Company and its stockholders. All other questions
concerning the construction, validity, enforcement and interpretation of this
Warrant shall be governed by the internal law of the State of Arizona, without
giving effect to any choice of law or conflict of law

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provision or rule (whether of the State of Arizona or any other jurisdictions)
that would cause the application of the laws of any jurisdictions other than the
State of Arizona.

                  IN WITNESS WHEREOF, the Company has caused this Warrant to be
signed and attested by its duly authorized officers under its corporate seal and
to be dated the Date of Issuance hereof.


                                               ALLIANCE MEDICAL CORPORATION


                                               By____________________________

                                               Its___________________________


[Corporate Seal]

Attest:


____________________________
         Secretary


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                                                                       EXHIBIT I

                               EXERCISE AGREEMENT

To:                                           Dated:

                  The undersigned, pursuant to the provisions set forth in the
attached Warrant, hereby agrees to subscribe for the purchase of ______ shares
of the Common Stock covered by such Warrant and makes payment herewith in full
therefor at the price per share provided by such Warrant.


                                         Signature ____________________

                                         Address ______________________


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                                                                      EXHIBIT II

                                   ASSIGNMENT


                  FOR VALUE RECEIVED, _____________________________ hereby
sells, assigns and transfers all of the rights of the undersigned under the
attached Warrant with respect to the number of shares of the Common Stock
covered thereby set forth below, unto:

Names of Assignee                    Address                      No. of Shares




Dated:                                 Signature        _______________________

                                                        _______________________

                                       Witness          _______________________



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