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                                                                   EXHIBIT 3.121

                                     BYLAWS

                                       OF

                         MARTELL MEDICAL PRODUCTS, INC.

                                    ARTICLE I
                                     OFFICES

SECTION 1.  PRINCIPAL EXECUTIVE OFFICE

The principal executive office of the corporation shall be in the City of
Riverside, County of Riverside, State of California.

The corporation may also have offices at such other places as the Board of
Directors may from time to time designate, or as the business of the corporation
may require.

                                   ARTICLE II
                              SHAREHOLDERS' MEETING

SECTION 1.  PLACE OF MEETINGS

All meetings of the shareholders shall be held at the principal executive office
of the corporation or at such other place as may be determined by the Board of
Directors.

SECTION 2.  ANNUAL MEETINGS

AMENDED TO SIXTY DAYS AFTER FYE BY SHARE HOLDERS ON JULY 26, 1995.

The annual meeting of the shareholders shall be held on the penultimate or last
month of the annual year as determined by the Board of Directors, at which time
the Shareholders will transact any proper business.

SECTION 3.  SPECIAL MEETINGS

Special meetings of the shareholders may be called by the President or by one or
more shareholders holding at least ten percent of the voting power of the
corporation.

SECTION 4.  NOTICE OF MEETINGS

Notices of meetings, annual or special, shall be given in writing to
Shareholders entitled to vote at the meeting by the Secretary or an Assistant
Secretary.

Such notices shall be given either personally or by first class mail or other
means of written communication, addressed to the Shareholder at the address of
such Shareholder appearing on the books of the corporation or given by the
shareholder to the corporation for the purpose of notice. Notice shall be given
not less than ten (10) nor more than sixty (60) days before the date of the
meeting.

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Such notice shall state the place, date and hour of the meeting and (1) in the
case of a special meeting, the general nature of the business to be transacted,
and that no other business may be transacted, or (2) in the case of an annual
meeting, those matters which the Board at the time of the mailing of the notice,
intends to present for action by the shareholders, but subject to the provisions
of Section 6 of this Article that any proper matter may be presented at the
meeting for such action. The notice of any meeting at which Directors are to be
elected shall include the names of the nominees which, at the time of the
notice, the Board of Directors intends to present for election. Notice of any
adjourned meeting need not be given unless a meeting is adjourned for forty-five
(45) days or more from the date set for the original meeting.

SECTION 5.  WAIVER OF NOTICE

The transactions of any meeting of shareholders, however called and noticed, and
wherever held, are as valid as though had at a meeting duly held after regular
call and notice, if a quorum is present, whether in person or by proxy, and if,
either before or after the meeting, each of the persons entitled to vote, not
present in person or by proxy, signs a written waiver of notice or a consent to
the holding of the meeting or an approval of the minutes thereof. All such
waivers or consents and approvals shall be filed with the corporate records or
made a part of the minutes of the meeting. Neither the business to be transacted
at the meeting, nor the purpose of any regular or special meeting of
shareholders need be specified in any written waiver of notice, except as
provided in Section 6 of this Article.

SECTION 6.  SPECIAL NOTICE AND WAIVER OF NOTICE REQUIREMENT

Except as provided below, any shareholder approval at a meeting with respect to
the following proposals, shall be valid only if the general nature of the
proposal so approved was stated in the notice of meeting, or in any written
waiver of notice:

     1. Approval of a contract or other transaction between the corporation and
one or more of its Directors or between the corporation and any corporation,
firm or association in which one or more of the directors has a material
financial interest, pursuant to Section 310 of the California Corporations Code;

     2. Amendment of the Articles of Incorporation after any shares have been
issued pursuant to Section 902 of the California Corporations Code;

     3. Approval of the principal terms of a reorganization pursuant to Section
1201 of the California Corporations Code;

     4. Election to voluntarily dissolve the corporation pursuant to Section
1900 of the California Corporations Code; and

     5. Approval of a plan of distribution of shares as part of the winding up
of the corporation pursuant to Section 2007 of the California Corporations Code.

Approval of the above proposals at a meeting shall be valid with or without

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such notice, if by the unanimous approval of those entitled to vote at the
meeting.

SECTION 7.  ACTION WITHOUT MEETING

Any action which may be taken at any annual or special meeting of shareholders
may be taken without a meeting and without prior notice if a consent, in
writing, setting forth the action so taken, shall be signed by the holders of
outstanding shares having not less than the minimum number of votes that would
be necessary to authorize or take such action at a meeting at which all shares
entitled to vote thereon were present and voted.

Unless the consents of all shareholders entitled to vote have been solicited in
writing, notice of any shareholders' approval, with respect to any one of the
following proposals, without a meeting, by less than unanimous written consent
shall be given at least ten (10) days before the consummation of the action
authorized by such approval:

     1. Approval of a contract or other transaction between the corporation and
one or more of its Directors or another corporation, firm or association in
which one or more of its directors has a material financial interest, pursuant
to Section 310 of the California Code;

     2. To approve the principal terms of a reorganization, pursuant to Section
1201 of the California Corporations Code; or

     3. Approval of a plan of distribution as part of the winding up of the
corporation pursuant to Section 2007 of the California Corporations Code.

     4. To adopt, amend or approve by laws.

Prompt notice shall be given of the taking of any other corporate action
approved by shareholders without a meeting by less than a unanimous written
consent to those shareholders entitled to vote who have not consented in
writing.

Notwithstanding any of the foregoing provisions of this section, Directors may
not be elected by written consent except by the unanimous written consent of all
shares entitled to vote for the election of Directors.

A written consent may be revoked by a writing received by the corporation prior
to the time that written consents of the number of shares required to authorize
the proposed action have been filed with the Secretary of the corporation, but
may not be revoked thereafter. Such revocation is effective upon its receipt by
the Secretary of the corporation.

SECTION 8.  QUORUM

A majority of the shares entitled to vote, represented in person or by proxy,
shall constitute a quorum at a meeting of shareholders. If a quorum is present,
the affirmative vote of the majority of shares represented at the meeting and
entitled to vote on any matter shall be the act of the shareholders, unless the

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Amended by action of the Shareholders July 24, 1996

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vote of a greater number is required by law and except as provided in the
following provisions of this section. One vote will be allowed per share owned
by any given shareholder thus each shareholder will carry the same voting power
as the number of shares held by that shareholder.

The shareholders present at a duly called or held meeting at which a quorum is
present may continue to transact business until adjournment notwithstanding the
withdrawal of enough shareholders to leave less than a quorum, if any action is
approved by at least a majority of the shares required to constitute a quorum.

In the absence of a quorum, any meeting of shareholders may be adjourned from
time to time by the vote of a majority of the shares represented either in
person or by proxy, but no other business may be transacted except as provided
in the foregoing provisions of this section.

SECTION 9.  VOTING

Only persons in whose names shares entitled to vote stand on the record date for
voting purposes fixed by the Board of Directors pursuant to Article VIII,
Paragraph 3 of these Bylaws, or, if there be no such data so fixed, on the
record dates given below, shall be entitled to vote at such meeting.

     If no record date is fixed:

     1. The record date for determining shareholders entitled to notice of, or
to vote at a meeting of shareholders shall be at the close of business on the
business day next preceding the day on which notice is given or, if notice is
waived, at the close of business on the business day next preceding the day on
which the meeting is held.

     2. The record date for determining the shareholders entitled to give
consent to corporate actions in writing without a meeting, when no prior action
by the Board is necessary, shall be the day on which the first written consent
is given.

     3. The record date for determining shareholders for any other purpose shall
be at the close of business on the day on which the Board adopts the resolution
relating thereto, or the 60th day prior to the date of such other action,
whichever is later.

SECTION 10. PROXIES

Every person entitled to vote may authorize another person or persons to act by
proxy with respect to voting by filing a written proxy executed by such person
or his duly authorized agent, with the secretary of the Corporation.

A proxy shall not be valid after the expiration of eleven (11) months from the
date thereof unless otherwise provided in the proxy. Every proxy continues in
full force and effect until revoked by the person executing it prior to the vote
pursuant thereto, except as otherwise provided in Section 705 of the California
Corporations Code.

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                                   ARTICLE III
                              DIRECTORS, MANAGEMENT

SECTION 1.  POWERS

Subject to any limitations in the Articles of Incorporation and to the
provisions of the California Corporations Code, the business and affairs of the
corporation shall be managed and all corporate powers shall be exercised by, or
under the direction of the Board of Directors.

SECTION 2.  NUMBER

The authorized number of Directors shall be determined by a majority of the
outstanding shares entitled to vote; provided, however, that a Bylaw reducing
the fixed number of Directors to a number less than one (1) cannot be adopted
unless in accordance with the provisions of Section 212 of the California
Corporations Code. The authorized number of directors shall be Three.

SECTION 3.  ELECTION AND TENURE OF OFFICE

The Directors shall be elected at the annual meeting of the shareholders and
hold office until the next annual meeting and until their successors have been
elected and qualified.

SECTION 4.  VACANCIES

A vacancy on the Board of Directors shall exist in the case of death,
resignation or removal of any Director, or in case the authorized number of
Directors is increased, or in case the shareholders fail to elect the full,
authorized number of Directors at any annual or special meeting of the
shareholders at which any Director who has been declared of unsound mind by an
order of court, or who has been convicted of a felony.

Except for a vacancy created by the removal of a Director, vacancies on the
Board of Directors may be filled by an unanimous vote of the Directors then in
office, whether or not less than a quorum, or by a sole remaining Director, and
each Director so elected shall hold office until the next annual meeting of the
shareholders and until his successor has been elected and qualified. The
shareholders may elect a Director at any time to fill a vacancy not filled by
the Directors. Any such election by written consent requires the unanimous
consent of the shareholders entitled to vote. Any director may resign effective
upon giving written notice to the Chairman of the Board of Directors, the
President, the Secretary or the Board of Directors of the corporation unless the
notice specifies a later time for the effectiveness of such resignation. If the
resignation is effective at a later time, a successor may be elected to take
office when the resignation becomes effective. Any reduction of authorized
number of Directors does not remove any Director prior to the expiration of such
Director's term in office.

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SECTION 5.  REMOVAL

Any or all of the Directors may be removed if such removal is approved by a
majority of shares entitled to vote, subject to the provisions of Section 303 of
the California Corporation Code.

Except as provided in Sections 302, 303, and 304 of the California Corporations
Code, a Director may not be removed prior to the expiration of such Director's
term of office.

The Superior Court of the proper county may, on the suit of shareholders holding
at least 50 percent of the number of outstanding shares, remove from office any
Director in case of fraudulent or dishonest acts or gross abuse from re-election
any Director so removed for a period prescribed by the court. The corporation
shall be made a party to such action.

SECTION 6.  PLACE OF MEETINGS

Meetings of the Board of Directors shall be held at any place, within or without
the State of California which has been designated in the notice of the meeting,
or, if not stated in the notice or there is no notice, at the principal
executive office of the corporation or as designated from time to time by
resolution of the Board of Directors.

SECTION 7.  CALL AND NOTICE OF MEETINGS

Meetings of the Board of Directors may be called by the Chairman of the Board,
or the President, or Vice President, or Secretary or any two Directors.

Regular meetings of the Board of Directors shall be held with a minimum of ten
days and a maximum of sixty days notice. Special meetings of the Board of
Directors shall be held upon four (4) days notice by mail, or 48 hours notice
delivered personally or by telephone or telegraph. A notice or waiver of notice
need not specify the purpose of any special meeting of the Board of Directors.

SECTION 8.  QUORUM

A quorum of all meetings of the Board of Directors shall be a majority of the
authorized number of Directors.

Every act or decision done or made by a majority of the Directors present at a
meeting duly held at which a quorum is present is the act of the Board, subject
to the provisions of Section 310 and subdivision (e) of Section 317 of the
California Corporations Code. A meeting at which a quorum is initially present
may continue to transact business notwithstanding the withdrawl of Directors, if
any action taken is approved at least a majority of the required quorum for such
meeting.

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Amended by action of the Shareholders July 24, 1996

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SECTION 9.  WAIVER OF NOTICE

The transactions of any meeting of the Board, however called and noticed or
wherever held, are as valid as though had at a meeting duly held after regular
call and notice if a quorum is present and it, either before or after the
meeting, each of the Directors not present signs a written waiver of notice, a
consent to holding the meeting or an approval of the minutes thereof. All such
waivers, consents and approvals shall be filed with the corporate records or
made a part of the minutes of the meeting.

SECTION 10. ACTION WITHOUT MEETING

Any action required or permitted to be taken by the Board may be taken without a
meeting, if a quorum of the Board shall individually or collectively consent in
writing to such action. Such written consent or consents shall be filed with the
minutes of the proceedings of the Board. Such action by written consent shall
have the same force and effect as a vote of such Directors.

SECTION 11. COMPENSATION

No salary shall be paid Directors, as such, for their services, but, by
resolution, the Board of Directors may allow a fixed sum and expenses to be paid
for attendance at regular or special meetings. Nothing contained herein shall
prevent a Director from serving the corporation in any other capacity and
receiving compensation therefore. Members of special or standing committees may
be allowed like compensation for attendance at meetings.

                                   ARTICLE IV
                                    OFFICERS

SECTION 1.  OFFICERS

The officers of the corporation shall be a President, Vice-President, a
Secretary and a Treasurer. The corporation may also have such other officers
with such titles and duties as shall be determined by the Board of Directors.
Any number of offices may be held by the same person.

SECTION 2.  ELECTION

All officers of the corporation shall be chosen by the stock holders. Each
officer shall hold office until his death, resignation or removal or until his
successor shall be chosen and qualified. A vacancy in any office because of
death, resignation or removal or other cause shall be filled by the Board.

SECTION 3.  REMOVAL AND RESIGNATION

An officer may be removed at any time, either with or without cause, by the
Board. An officer may resign at any time upon written notice to the corporation
given to the Board, the President, or the Secretary of the corporation. Any

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such resignation shall take effect at the day of receipt of such notice or at
any other time specified therein. The acceptance of a resignation shall not be
necessary to make it effective.

SECTION 4.  PRESIDENT

The President shall be the chief executive officer of the corporation and shall
have general supervision, direction and control of the business affairs of the
corporation. He shall preside at all meetings of the shareholders and Directors
and be an ex-officio member of all the standing committees, including the
executive committee, if any, and shall have the general powers and duties of
management usually vested in the office of President of a corporation, and shall
have such other powers and duties as may from time to time be prescribed by the
Board of Directors or the Bylaws.

SECTION 5.  VICE-PRESIDENT

In the absence or disability of the President, the Vice-Presidents, in order of
their rank as fixed by the Board of Directors, or if not ranked, the
Vice-President designated by the Board, shall perform all the duties of the
President, and when so acting, shall have all the powers of, and be subject to
all the restrictions upon, the President. Each Vice-President shall have such
other powers and perform such other duties as may from time to time be
prescribed by the Board of Directors or the Bylaws.

SECTION 6.  SECRETARY

The Secretary shall keep, or cause to be kept, at the principal executive office
of the corporation, a book of minutes of all meetings of Directors and
shareholders, with the time and place of holding, whether regular or special,
and, if special, how authorized, the notice thereof given or the waivers of
notice, the names of those present at Directors' meetings, the number of shares
present or represented at shareholders' meetings and the proceedings thereof.

The Secretary shall keep, or cause to be kept, at the principal executive office
of the corporation, or at the office of the corporation's transfer agent, a
share register, showing the names of the shareholders and their addresses, the
number of classes of shares held by each, the number and date of certificates
issued for shares, and the number and date of cancellation of every certificate
surrendered for cancellation.

The Secretary shall keep, or cause to be kept, at the principal executive office
of the corporation, the original or a copy of the Bylaws as amended or otherwise
altered to date, certified by him.

The Secretary shall give, or cause to be given, notice of all meetings of
shareholders and Directors required to be given by law or the Bylaws.

The Secretary shall have charge of the seal of the corporation and have such
other powers and perform such other duties as may from time to time be
prescribed by the Board or the Bylaws.

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SECTION 7.  TREASURER

The Treasurer shall keep and maintain or cause to be kept and maintained,
adequate and correct books and records of accounts of the properties and
business transactions of the corporation.

The Treasurer shall deposit moneys and other valuables in the name and to the
credit of the corporation with such depositaries as may be designated by the
Board of Directors. He shall disburse the funds of the corporation in payment of
the just demands against the corporation or as may be ordered by the Board of
Directors; shall render to the President and Directors, whenever they request
it, an account of all his transactions as Treasurer and of the financial
condition of the corporation, and shall have such other powers and perform such
other duties as may from time to time be prescribed by the Board of Directors or
the Bylaws.

In the absence or disability of the Treasurer, the Assistant Treasurers, if any,
in order of their rank as fixed by the board of Directors or if not ranked, the
Assistant Treasurer designated by the Board of Directors, shall perform all the
duties of the Treasurer, and when so acting, shall have all the powers of, and
be subject to all the restrictions upon the Treasurer. The Assistant Treasurers,
if any, shall have such other powers and perform such other duties as may from
time to time be prescribed by the Board of Directors or the Bylaws.

SECTION 8.  COMPENSATION

The salaries of the officers shall be fixed, from time to time, by the Board of
Directors.

                                    ARTICLE V
                              EXECUTIVE COMMITTEES

SECTION 1.

The Board may, by resolution adopted by a majority of the authorized number of
Directors, designate one or more committees, each consisting of one or more
Directors, to serve at the pleasure of the Board. Any such committee, to the
extent provided in the resolution of the Board, shall have all the authority of
the Board, except with respect to:

     a. The approval of any action for which this division also requires
shareholders' approval.

     b. The filling of vacancies on the Board or in any committee.

     c. The fixing of compensation of the Directors for serving on the Board or
on any committee.

     d. The amendment or repeal of Bylaws or the adoption of new Bylaws.

     e. The amendment or repeal of any resolution of the Board which by its
express terms is not so amenable or repealable.

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     f. A distribution to the shareholders of the corporation, except at a rate
or in a periodic amount or within a price range determined by the Board.

     g. The appointment of other committees of the Board or the members thereof.

                                   ARTICLE VI
                          CORPORATE RECORDS AND REPORTS

SECTION 1.  INSPECTION BY SHAREHOLDERS

The share register shall be open to inspection and copying by any shareholder or
holder of a voting trust certificate at any time during usual business hours
upon written demand on the corporation, for a purpose reasonably related to such
holder's interest as a shareholder or holder of a voting trust certificate. Such
inspection and copying under this section may be made in person or by agent or
attorney.

The accounting books and records and minutes of proceedings of the shareholders
and the Board and committees of the Board also shall be open to inspection upon
the written demand on the corporation of any shareholder or holder of a voting
trust certificate at any reasonable time during usual business hours, for a
purpose reasonably related to such holder's interest as a shareholder or as the
holder of such voting trust certificate. Such inspection by a shareholder or
holder of voting trust certificate may be made in person or by agent or
attorney, and the right of inspection includes the right to copy and make
extracts.

Shareholders shall also have the right to inspect the original or copy of these
Bylaws, as mended to date, kept at the corporation's principal executive office
at all reasonable times during business hours.

SECTION 2.  INSPECTION BY DIRECTORS

Every Director shall have the absolute right at any reasonable time to inspect
and copy all books, records and documents of every kind and to inspect the
physical properties of the corporation, domestic or foreign, of which such
person is a Director. Such inspection by a Director may be made in person or by
agent or attorney and the right of inspection includes the right to copy and
make extracts.

SECTION 3.  RIGHT TO INSPECT WRITTEN RECORDS

If any record subject to inspection pursuant to this chapter is not maintained
in written form, a request for inspection is not complied with unless and until
the corporation at its expense makes such record available in written form.

SECTION 4.  WAIVER OF ANNUAL REPORT

The annual report to shareholders, described in Section 1501(a) of the
California Corporations Code is hereby expressly waived.

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SECTION 5.  CONTRACTS, ETC.

The Board of Directors, except as otherwise provided in the Bylaws, may
authorize any officer or officers, agent or agents, to enter into any contract
or execute any instrument in the name and on behalf of the corporation. Such
authority may be general or confined to specific instances. Unless so authorized
by the Board of Directors, no officer, agent or employee shall have any power or
authority to bind the corporation by any contract or engagement, or to pledge
its credit, or to render it liable for any purpose or to any amount.

                                   ARTICLE VII
                       INDEMNIFICATION OF CORPORATE AGENTS

SECTION 1.

The corporation shall indemnify each of its agents against expenses, judgments,
fines, settlements and other amounts, actually and reasonably incurred by such
person by reason of such person's having been made or having been threatened to
be made a party to a proceeding, to the fullest extent permissible by the
provisions of Section 317 of the California Corporations Code. The corporation
shall advance the expenses reasonably expected to be incurred by such agent in
defending any such proceeding upon receipt of the undertaking required by
subdivision (f) of such section. The terms "agent", "proceeding" and "expenses"
used in this Section 1 shall have the same meaning as such terms in said Section
317 of the California Corporations Code.

                                  ARTICLE VIII
                                     SHARES

SECTION 1.  CERTIFICATES

The corporation shall issue certificates for its shares when fully paid.
Certificates of stock shall be issued in numerical order, and state the name of
the recordholder of the shares represented thereby; the number, designation, if
any, and class or series of shares represented thereby and contain any statement
or summary required by an applicable provision of the California Corporations
Code.

Every certificate for shares shall be signed in the name of the corporation by
the Chairman or Vice-Chairman of the Board or the President or Vice-President,
and the Treasurer, the Secretary or an Assistant Secretary.

SECTION 2.  TRANSFER OF SHARES

Upon surrender to the Secretary to transfer agent of the corporation of a
certificate for shares duly endorsed or accompanied by proper evidence of
succession, assignment or authority to transfer, it shall be the duty of the
Secretary of the corporation to issue a new certificate to the person entitled
thereto, cancel the old certificate and record the transaction upon its share
register.

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SECTION 3.  RECORD DATE AND CLOSING OF TRANSFER BOOKS

The Board of Directors may fix a time in the future as a record date for the
determination of the shareholders or entitled to receive payment of any dividend
or distribution, or any allotment of rights, or to exercise rights in respect to
any other lawful action. The record date so fixed shall not be more than sixty
(60) nor less than ten (10) days prior to the date of the meeting or event for
the purpose of which it is fixed. When a record date is so fixed, only
shareholders of record on that date are entitled to notice of and to vote at the
meeting or to receive the dividend, distribution, or allotment or rights, or to
exercise the rights as the case may be, notwithstanding any transfer of any
shares on the books of the corporation after the record date.

The Board of Directors may close the books of the corporation against transfers
of shares during the whole or any part of a period of not more than sixty (60)
days prior to the date of a shareholders' meeting, the date when the right to
any dividend, distribution, or allotment of rights vest, or the effective date
of any change, conversion or exchange of shares.

                                   ARTICLE IX
                               AMENDMENT OF BYLAWS

SECTION 1.  BY SHAREHOLDERS

Bylaws may be adopted, amended or repealed by the vote or the written consent of
a majority of the outstanding shares qualified to vote.

                                   CERTIFICATE

This is to certify that the foregoing is a true and correct copy of the Bylaws
of the Corporation named in the title thereto and that such Bylaws were duly
adopted by the Board of Directors of said Corporation on the date set forth
below.

     Dated: August 12, 1996

                                             /s/ Allan R. McDonald
                                             -----------------------------------
                                               Allan R. McDonald
                                             Secretary / Treasurer

(seal)

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Amended by action of the Shareholders July 24, 1996