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                                                                    Exhibit 3.50

                                     BYLAWS

                                       OF

                  NORTHWEST EMERGENCY PHYSICIANS, INCORPORATED

                                    ARTICLE I

                                  SHAREHOLDERS

                  Section 1. Annual Meeting. The annual meeting of the
shareholders for the election of directors and for the transaction of such other
business as may properly come before the meeting shall be held at such place,
either within or without the State of Washington, on such date, and at such
time, as the Board of Directors may by resolution provide, or if the Board of
Directors fails to provide, then such meeting shall be held at the principal
office of the Corporation at 10:00 a.m., on the fourth Friday of the fourth
calendar month after the end of the Corporation's fiscal year, if not a legal
holiday under the laws of the State of Washington, and if a legal holiday, on
the next succeeding day.

                  Section 2. Special Meetings. Special meetings of the
shareholders may be called by the Board of Directors, by the President, or by
the Corporation upon the written request (which request shall set forth the
purpose or purposes of the meeting) of the shareholders of record (see Section
6(b) of Article I of these Bylaws) of outstanding shares representing a least
25% of all the votes entitled to be cast on any issue proposed to be considered
at the proposed special meeting. In the event such meeting is called by the
Board of Directors, such meeting may be held at such place, either within or
without the State of Washington, as is stated in the call and notice thereof. If
such Meeting is called at the request of shareholders as provided in this
Section 2, then such meeting shall be held at the principal office of the
corporation.

                  Section 3. Notice of Meetings. A written or printed notice
stating the place, day and hour of the meeting, and in case of a special meeting
the purpose or purposes for which the meeting is called, shall be delivered or
mailed by the Secretary of the Corporation to each holder of record of stock of
the Corporation at the time entitled to vote, at his address as it appears upon
the records of the corporation not, less 10 nor more than 60 days prior to such
meeting. If the Secretary fails to give such notice within 20 days after the
call of a meeting, the person calling or requesting such meeting, or any person
designated by them may give such notice. Notice of such meeting may be waived in
writing by any shareholder. Notice of any adjourned meeting of the shareholders
shall not be required if the time and place to which the meeting is adjourned
are announced at the meeting at which the adjournment is, taken, unless the
Board of Directors sets a new record date for such meeting in which case notice
shall be given in the manner provided in this Section 3.

                  Section 4. Quorum and Shareholder Vote. A quorum for action on
any subject matter at any annual or special meeting of exist when the holders of
shares entitled to vote a majority of the votes entitled to be cast on such
subject matter are represented in person or by proxy at such meeting. If a
quorum is present, the affirmative vote of such number of shares as is required
by the Washington Business Corporation Act (as in effect at the time the vote is
taken), for approval of the subject matter being voted upon shall be the act of
the shareholders, unless a greater vote is required
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by the Articles of Incorporation or these Bylaws. If a quorum is not present, a
meeting of shareholders may be adjourned from time to time by the vote of shares
having a majority of the votes of the shares represented at such meeting, until
a quorum is present. When a quorum is present at the reconvening of any
adjourned meeting, and if the requirements of Section 3 of this Article I have
been observed, then any business may be transacted at such reconvened meeting in
the same manner and to the same extent as it might have been transacted at the
meeting as originally noticed.

                  Section 5. Proxies. A shareholder may vote either in person or
by proxy duly executed in writing by the shareholder. Unless written notice to
the contrary is delivered to the Corporation by the shareholder, a proxy for any
meeting shall be valid for any reconvention of any adjourned meeting.

                  Section 6.  Fixing Record Date

                  (a) Except as provided in paragraph (b) of this Section 6, for
the purpose of determining shareholders entitled to notice of or to vote at any
meeting of shareholders or any adjournment thereof, or entitled to receive
payment of any dividend, or in order to make a determination of shareholders for
any other proper purpose, the Board of Directors shall have the power to fix a
date, not more than 70 days prior to the date on which the particular action
requiring a determination of shareholders is to be taken, as the record date for
any such determination of shareholders. A record date for the determination of
shareholders entitled to notice of or to vote at any meeting of shareholders or
any adjournment thereof shall not be set less than 10 days prior to such
meeting, provided that the record date for the determination of shareholders
entitled to notice of or to vote at any special meeting of shareholders called
by the Corporation at the request of holders of shares pursuant to Section 2 of
Article I hereof or any adjournment thereof shall be 20 days after the
"Determination Date" (as defined in paragraph (b) of this Section 6), and
provided further that such record date shall be 70 days prior to such special
meeting. In any case where a record date is set, under any provision of this
Section 6, only shareholders of record on the said date shall be entitled to
participate in the action for which the determination of shareholders of record
is made, whether the action is payment of a dividend, allotment of any rights or
any change or conversion or exchange of capital stock or other such action, and,
if the record date is set for the determination of shareholders entitled to
notice of or to vote at a meeting of shareholders, only such shareholders of
record shall be entitled to such notice or vote, notwithstanding any transfer of
any shares on the books of the Corporation after such record date.

                  (b) (i) In order that the Corporation may determine the
shareholders entitled to request a special meeting of the shareholders or a
special meeting in lieu of the annual meeting of the shareholders pursuant to
Section 2 of Article I hereof, the Board of Directors may fix a record date,
which record date shall not precede the date upon which the resolution fixing
the record date is adopted by the Board of Directors, and which date shall not
be more than 10 days after the date upon which the resolution fixing the record
date is adopted by the Board of Directors. Any shareholder of record seeking to
have the shareholders request such a special meeting shall by written notice to
the Secretary request the Board of Directors to fix a record date. The Board of
Directors shall, within 10 business days after the date on which such a request
is received, adopt a resolution fixing the record date. If no record date has
been fixed by the Board of Directors within


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10 business days after the date on which such a request is received, the record
date for determining shareholders entitled to request such a special meeting
shall be the first day on which a signed written request setting forth the
request to fix a record date is delivered to the Corporation by delivery to its
principal place of business, or any officer or agent of the Corporation having
custody of the books in which proceedings of meetings of shareholders are
recorded.

                  (ii) Every written request for special meeting shall bear the
date of signature of each shareholder who signs the request and no such request
shall be effective to request such a meeting unless, within 70 days after the
record date established in accordance with paragraph (b)(i) of this Section,
written requests signed by a sufficient number of record holders as of such
record date to request a special meeting in accordance with Section 2 of Article
I hereof are delivered to the Corporation in the manner prescribed in paragraph
(b)(i) of this Section.

                  (iii) In the event of the delivery, in the manner provided by
this Section, to the Corporation of the requisite written request or requests
for a special meeting and/or any related revocation or revocations, the
Corporation shall engage nationally recognized independent inspectors of
elections for the purpose of promptly performing a ministerial review of the
validity of the requests and revocations. For the purpose of permitting a prompt
ministerial review by the independent inspectors, no request by shareholders for
a special meeting shall be effective until the earlier of (i) five business days
following delivery to the Corporation of requests signed by the holders of
record (on the record date established in paragraph (b)(i) of this Section) of
the requisite minimum number of shares that would be necessary to request such a
meeting under Section 2 of Article I hereof, or (ii) such date as the
independent inspectors certify to the Corporation that the requests delivered to
the Corporation in accordance with this Article represent at least the minimum
number of shares that would be necessary to request such meeting (the earlier of
such dates being herein referred to as the "Determination Date"). Nothing
contained in this paragraph shall in any way be construed to suggest or imply
that the Board of Directors or any shareholder shall not be entitled to contest
the validity of any request or revocation thereof, whether during or after such
five business day period, or to take any other action (including, without
limitation, the commencement, prosecution or defense of any litigation with
respect thereto).

                  (iv) Unless the independent inspectors shall deliver, on or
before the Determination Date, a certified report to the Corporation stating
that the valid requests for a special meeting submitted pursuant to paragraph
(iii) above represent less than the requisite minimum number of shares that
would be necessary to request a special meeting under Section 2 of Article I
hereof, the Board of Directors shall, within five business days after the
Determination Date, adopt a resolution calling a special meeting of the
shareholders and fixing a record date for such meeting, in accordance with
Section 6(a) of Article I of these Bylaws.

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                                   ARTICLE II

                                    DIRECTORS

                  Section 1. Powers of Directors. The Board of Directors shall
have the management of the business of the Corporation and, subject to any
restrictions imposed by law, by the Articles of Incorporation, or by these
Bylaws, may exercise all the powers of the Corporation.

                  Section 2. Number and Term of Directors. Except as provided in
this Section 2, one (1) Director shall constitute the full Board. At any annual
or special meeting the shareholders may, and at any meeting of directors, the
directors (by a vote of not less than 51% of the directors then in office) may,
fix a different number of Directors who shall constitute the full Board, but the
full Board shall consist of not less than one (1) nor more than three (3)
Directors.

                  Section 3. Meetings of the Directors. The Board of Directors
shall meet each year immediately following the annual meeting of shareholders,
and the Board may by resolution provide for the time and place of other regular
meetings. Special meetings of the Directors may be called by the President or by
any two of the Directors.

                  Section 4. Notice of Meetings. Notice of each meeting of the
Directors will be given by the Secretary by mailing the same at least ten days
before the meeting or by telephone, telegraph or cablegram or in person at least
five days before the meeting, to each Director, except that no notice need be
given of regular meetings fixed by the resolution of the Board or of the meeting
of the Board held at the place of and immediately following the annual meeting
of the shareholders. Any Director may waive notice, either before or after the
meeting, and shall be deemed to give waived notice if he is present at the
meeting.

                  Section 5. Action of Directors Without a Meeting. Any action
required by law to be taken at a meeting of the Board of Directors, or any
action which may be taken at a meeting of the Board of Directors, or of any
committee thereof, may be taken without a meeting if written consent, setting
forth the action so taken, shall be signed by all the Directors or all the
members of the committee, as the case may be, and be filed with the minutes of
the proceedings of the Board or the Committee. Such consent shall have the same
force and effect as a unanimous vote of the Board or the Committee, as the case
may be.

                  Section 6. Compensation. A fee and reimbursement for expenses
for attendance at meetings of the Board of Directors or any committee thereof
may be fixed by resolution of the Board of Directors.

                  Section 7. Removal. Any or all directors may be removed from
office at any time with or without cause.

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                                   ARTICLE III

                                    OFFICERS

                  Section 1. Officers. The officers of the Corporation shall
consist of a President, one or more Vice-Presidents, a Secretary and a
Treasurer, and such other officers or assistant officers as may be elected by
the Board of Directors. Any two offices may be held by the same person. The
Board may designate a Vice-President as an Executive Vice-President and may
designate the order in which the other Vice-Presidents may act.

                  Section 2. President. The President shall be the chief
operating officer of the Corporation. He shall, under the direction of the chief
executive officer, supervise the management of the day-to-day business of the
Corporation. He shall have such further powers and duties as from time to time
may be conferred on him by the Board of Directors and he shall preside at all
Meetings of the shareholders and the Board of Directors.

                  Section 3. Vice-President. The Vice-President shall act in the
case of the absence or disability of the President. If there is more than one
Vice-President, such Vice-Presidents shall act in the order of precedence, as
set out by the Board of Directors.

                  Section 4. Treasurer. The Treasurer shall be responsible for
the maintenance of proper financial books and records of the Corporation.

                  Section 5. Secretary. The Secretary shall keep the minutes of
the meetings of the shareholders and the Directors and shall have custody of and
attest the seal of the corporation.

                  Section 6. Other Duties and Authorities. Each officer,
employee and agent shall have such other duties and authorities as may be
conferred on them by the Board of Directors.

                  Section 7. Removal. Any officer may be removed at any time by
the Board of Directors. A contract of employment for a definite term shall not
prevent the removal of any officer, but this provision shall not prevent the
making of a contract of employment with any officer and shall have no affect
upon any cause of action which any officer may have as a result of removal in
breach of a contract of employment.

                                   ARTICLE IV
                        DEPOSITORIES, SIGNATURE AND SEAL

                  Section 1. Depositories. All funds of the Corporation shall be
deposited in the name of the Corporation in such depository or depositories as
the Board may designate and shall be drawn out on checks, drafts or other orders
signed by such officer, officers, agent or agents as the Board may from time to
time authorize.

                  Section 2. Contracts. All contracts and other instruments
shall be signed on behalf of the Corporation by the President or by such other
officer, officers, agent or agents, as the Board from time to time may by
resolution provide.

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                  Section 3. Seal. The corporation seal of the Corporation shall
be as follows:

                  The seal may be manually affixed to any document or may be
lithographed or otherwise printed on any document with the same force, and
effect as if it had been affixed manually. The signature of the Secretary or
Assistant Secretary shall attest the seal and may be a facsimile if and to the
extent permitted by law.

                                    ARTICLE V
                                 STOCK TRANSFERS

                  Section 1. Form and Execution of Certificates. The
certificates of shares of capital stock of the corporation shall be in such form
as may be approved by the Board of Directors and shall be signed by the
President or a Vice-President and by the Secretary or any Assistant Secretary or
the Treasurer or any Assistant Treasurer, provided that any such certificate may
be signed by the facsimile signature of either or both of such officers
imprinted thereon if the same is countersigned by a transfer agent of the
Corporation and provided further that certificates bearing the facsimile of the
signature of such officers imprinted thereon shall be valid in all respects as
if such person or persons were still in office, even though such officer or
officers shall have died or otherwise ceased to be officers.

                  Section 2. Transfers of Shares. Shares of stock in the
corporation shall be transferable only on the books of the Corporation by proper
transfer signed by the holder of record thereof or by a person duly authorized
to sign for such holder of record. The Corporation or its transfer agent or
agents shall be authorized to refuse any transfer unless and until it is
furnished such evidence as may reasonably require showing that the requested
transfer is proper.

                  Section 3. Lost, Destroyed or Stolen Certificates. Where the
holder of record of a share or shares of stock of the Corporation claims that
the certificate representing said share has been lost, destroyed or wrongfully
taken, the Board shall by resolution provide for the issuance of a certificate
to replace the original if the holder of record so requests before the
Corporation has notice that the certificate has been acquired by a bona fide
purchaser, files with the Corporation a sufficient indemnity bond, and furnishes
evidence of such loss, destruction or wrongful taking satisfactory to the
Corporation, in the reasonable exercise of its discretion. The Board may
authorize such officer or agent as it may designate to determine the sufficiency
of such an indemnity bond and to determine reasonably the sufficiency of the
evidence of loss, destruction or wrongful taking.

                  Section 4. Transfer Agent and Registrar. The Board may (but
shall not be required to) appoint a transfer agent or agents and a registrar or
registrars to transfers, and may require that all stock certificates bear the
signature of such transfer agent or of such transfer agent and registrar.

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                                   ARTICLE VI
                          INDEMNIFICATION OF DIRECTORS

                  Section 1. Actions Against Directors. The Corporation shall
indemnify to the fullest extent permitted by the Washington Business Corporation
Act, any individual, made a party to a proceeding (as defined in the Washington
Business Corporation Act) because he is or was a director, against liability (as
defined in the Washington Business Corporation Act), incurred in the proceeding,
if he acted in a manner he believed in good faith to be in or not opposed to the
best interests of the Corporation and, in the case of any criminal proceeding,
he had no reasonable cause to believe the conduct was unlawful.

                  Section 2. Advances for Expenses of Directors. The Corporation
shall pay for or reimburse the reasonable expenses incurred by a director who is
a party to a proceeding if:

                  (a)      The director furnishes the Corporation a written
                           affirmation of his good faith belief that he has met
                           the standard of conduct set forth in Section 1 above;
                           and

                  (b)      The director furnishes the Corporation a written
                           undertaking, executed personally on his behalf to
                           repay any advances if it is ultimately determined
                           that he is not entitled to indemnification.

                  The written undertaking required by paragraph (b) above must
be an unlimited general obligation of the director but need not be secured and
may be accepted without reference to financial ability to make repayment.

                                   ARTICLE VII
                               AMENDMENT OF BYLAWS

                  Section 1. Amendment. These Bylaws may be altered, amended,
repealed or new Bylaws adopted by the Board of Directors by the affirmative vote
of a majority of all directors then holding office, but any bylaws adopted by
the Board of Directors may be altered, amended, repealed or any new bylaws
adopted, by the shareholders at an annual, or special meeting of shareholders,
when notice of any such proposed alteration, amendment, repeal or addition shall
have been given in the notice of such meeting. The shareholders may prescribe
that any bylaw or bylaws adopted by them shall not be altered, amended or
repealed by the Board of Directors.

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