EXHIBIT 3.159

                                TSI ALLSTON, INC.

                                     BY-LAWS

                                    ARTICLE I

                                     OFFICES

                  SECTION 1. REGISTERED OFFICE. The registered office of the
Corporation shall be established and maintained at the office of The Corporation
Trust Company, in the City of Wilmington, in the County of New Castle, in the
State of Delaware, and said corporation shall be the registered agent of the
Corporation in charge thereof.

                  SECTION 2. OTHER OFFICES. The Corporation may have other
offices, either within or without the State of Delaware, at such place or places
as the board of directors may from time to time appoint or the business of the
Corporation may require.

                                   ARTICLE II

                            MEETINGS OF STOCKHOLDERS

                  SECTION 1. ANNUAL MEETINGS. Annual meetings of stockholders
for the election of directors and for such other business as may properly come
before the meeting shall be held at such place, either within or without the
State of Delaware, and at such time and date within thirteen months after the
preceding annual meeting, as the chairman, the president, or the board of
directors shall determine.

                  SECTION 2. SPECIAL MEETINGS. Special meetings of stockholders
for any purpose or purposes may be held at such time



and place, within or without the State of Delaware, as shall be stated in the
notice of the meeting. Special meetings of stockholders may be called by the
president or secretary or by resolution of the board of directors.

                  SECTION 3. VOTING. Each stockholder entitled to vote in
accordance with the terms of the certificate of incorporation and in accordance
with the provisions of these by-laws shall be entitled to one vote, in person or
by proxy, for each share of stock entitled to vote held by such stockholder, but
no proxy shall be voted more than three years after its date unless such proxy
provides for a longer period. Upon the demand of any stockholder, the vote for
directors and the vote upon any question before the meeting shall be by ballot.
All elections for directors shall be decided by plurality vote; all other
questions shall be decided by majority vote except as may be otherwise provided
by the certificate of incorporation or by the General Corporation Law of the
State of Delaware.

                  SECTION 4. LIST OF STOCKHOLDERS. A complete list of the
stockholders entitled to vote, arranged in alphabetical order with the address
of each and the number of shares held by each, shall be open to the examination
of any stockholder, for any purpose germane to any meeting, during ordinary
business hours, for a period of at least ten days prior to the meeting, either
at a place within the city where the meeting is to be held, which place shall be
specified in the notice of the meeting, or, if not so specified, at the place
where the meeting is to be held. The

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list shall also be produced and kept at the time and place of the meeting during
the whole time thereof, and may be inspected by any stockholder who is present.

                  SECTION 5. QUORUM. Except as otherwise required by law, by the
certificate of incorporation or by these by-laws, the presence, in person or by
proxy, of stockholders holding a majority of the stock of the corporation
entitled to vote shall constitute a quorum at all meetings of stockholders. In
case a quorum shall not be present at any meeting, a majority in interest of the
stockholders entitled to vote thereat, present in person or by proxy, shall have
power to adjourn the meeting from time to time, without notice other than
announcement at the meeting, until the requisite amount of stock entitled to
vote shall be present or represented. At any such adjourned meeting at which the
requisite amount of stock entitled to vote shall be present or represented, any
business may be transacted which might have been transacted at the meeting as
originally noticed, but only those stockholders entitled to vote at the meeting
as originally noticed shall be entitled to vote at any adjournment or
adjournments thereof.

                  SECTION 6. NOTICE OF MEETING. Written notice, stating the
place, date and time of the meeting and, in the case of a special meeting, the
purpose or purposes for which it is called, shall be given to each stockholder
entitled to vote thereat at his address as it appears on the records of the
Corporation, not less than ten nor more than sixty days before the date of the

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meeting. No business other than that stated in the notice shall be transacted at
any meeting without the unanimous consent of all the stockholders entitled to
vote thereat.

                  SECTION 7. STOCKHOLDER ACTION WITHOUT MEETING. Any action
required by the General Corporation Law of the State of Delaware to be taken at
any annual or special meeting of stockholders, or any action which may be taken
at any annual or special meeting of stockholders, may be taken without a
meeting, without prior notice and without a vote, if a consent in writing,
setting forth the action so taken, shall be signed by the holders of outstanding
stock 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. Prompt notice of the taking of the
corporation action without a meeting by less than unanimous written consent
shall be given to those stockholders who have not consented in writing.

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                                   ARTICLE III

                                    DIRECTORS

                  SECTION 1. NUMBER AND TERM; QUALIFICATIONS. The number of
directors which shall constitute the whole board of directors shall be not less
than one nor more than nine as fixed from time to time by resolution of the
board of directors or by the stockholders at an annual or special meeting;
provided, that no decrease in the number of directors shall shorten the term of
any incumbent director. The directors shall be elected at the annual meeting of
the stockholders, except that any vacancy may be filled as provided in Section 3
of this Article III of these by-laws. Each director shall hold office for a term
expiring at the annual meeting of stockholders next succeeding his election or
until his successor is elected and has qualified or until his earlier
resignation, removal or other vacation of office. A director need not be a
stockholder, a citizen of the United States or a resident of the State of
Delaware.

                  SECTION 2. RESIGNATIONS. Any director or member of a committee
may resign at any time upon written notice to the Corporation. Such resignation
shall be made in writing and shall take effect at the time specified therein or,
if no time is specified, at the time of its receipt by the president or
secretary. The acceptance of a resignation shall not be necessary to make it
effective.

                  SECTION 3. VACANCIES. If the office of any director or member
of a committee becomes vacant, or if any new

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directorship is created by an increase in the number of directors, the remaining
directors in office, though less than a quorum, by a majority vote, or the sole
remaining director may appoint any qualified person to fill such vacancy, and
such person shall hold office for the unexpired term and until his successor is
elected and has qualified or until his earlier displacement from office.

                  SECTION 4. REMOVAL. Any director may be removed either for or
without cause at any time by the affirmative vote of the holders of a majority
of the shares of stock outstanding and entitled to vote at a special meeting of
the stockholders called for that purpose, and the vacancies thus created may be
filled, at the meeting held for the purpose of removal or at any subsequent
meeting of stockholders, by a majority vote of the stockholders entitled to vote
and present or represented at such meeting.

                  SECTION 5. POWERS. The board of directors shall exercise all
of the powers of the Corporation except such as are by law, by the certificate
of incorporation or by these by-laws conferred upon or reserved to the
stockholders.

                  SECTION 6. COMMITTEES. The board of directors may, by
resolution or resolutions adopted by a majority of the members of the whole
board of directors, designate one or more committees, each committee to consist
of two or more of the directors of the Corporation. The board may designate one
or more directors as alternate members of any committee, who may replace any
absent or

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disqualified member at any meeting of the committee. Any such committee, to the
extent provided in the resolution, shall have and may exercise the powers of the
board of directors in the management of the business and affairs of the
Corporation (with the exception of any authority the delegation of which is
prohibited by Section 141 of the General Corporation Law of the State of
Delaware), and may authorize the seal of the Corporation to be affixed to all
papers which may require it. In the absence or disqualification of any member of
such committee or committees, the member or members thereof present at any
meeting and not disqualified from voting, whether or not he or they constitute a
quorum, may unanimously appoint another member of the board of directors to act
at the meeting in the place of any such absent or disqualified member.

                  SECTION 7. MEETINGS.

                  (a) Annual Meetings. The directors elected at each annual
meeting of stockholders shall hold their first meeting immediately thereafter,
if a quorum be present, or as soon as conveniently possible at a time and place
fixed by notice of meeting or by consent in writing of all the directors.

                  (b) Regular Meetings. Regular meetings of the board of
directors may be held without notice at such places and times as shall from time
to time be fixed in advance by resolution of the board of directors.

                  (c) Special Meetings. Special meetings of the board of
directors may be called by the president and, at the written

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request of any director, by the secretary, and shall be held at such time and
place as may be determined by the board of directors, or as shall be stated in
the notice of the meeting.

                  SECTION 8. QUORUM. Unless there is a board of one director,
one-third of the total number of directors (but in no case fewer than two
directors) shall constitute a quorum for the transaction of business. If at any
meeting of the board of directors less than a quorum shall be present, a
majority of those present may adjourn the meeting from time to time until a
quorum is obtained, and no further notice thereof need be given other than by
announcement at the meeting which shall be so adjourned.

                  SECTION 9. VOTING. The vote of a majority of the directors
present at any meeting at which a quorum is present, and the vote of a majority
of the entire membership of a committee of the board of directors shall be the
act of such board of such committee, except as may be otherwise specifically
provided by statute or by these by-laws. Members of the board of directors or of
any committee thereof may participate in a meeting of such board or committee by
means of conference telephone or similar communications equipment whereby all
participants can hear each other, such participation constituting presence in
person at such meeting.

                  SECTION 10. COMPENSATION. Directors shall not receive any
stated salary for their services as directors or as members of committees, but
by resolution of the board of directors a

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fixed fee and expenses of attendance may be allowed for attendance at each
meeting. Nothing herein contained shall be construed to preclude any director
from serving the Corporation in any other capacity as an officer, agent or
otherwise, and receiving compensation therefor.

                  SECTION 11. ACTION WITHOUT MEETING. Any action required or
permitted to be taken at any meeting of the board of directors or of any
committee thereof may be taken without a meeting if all members of the board or
committee, as the case may be, consent thereto in writing, and the writing or
writings are filed with the minutes of proceedings of the board or committee.

                                   ARTICLE IV

                                    OFFICERS

                  SECTION 1. OFFICERS. The officers of the Corporation shall be
a president, a treasurer and a secretary. In addition, the board of directors
may elect a chairman of the board of directors, one or more executive vice
presidents and one or more other vice presidents. None of the officers except
the chairman of the board of directors need be a director. Officers shall be
elected at the first meeting of the board of directors after each annual meeting
of stockholders and shall hold office until their successors are elected and
qualified or until earlier resignation or removal. More than two offices may be
held by the same person, but no officer shall execute, acknowledge or verify any
instrument in more than one capacity. Any officer may (subject

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to contractual commitments with the Corporation) resign at any time upon written
notice to the Corporation, and vacancies shall be filled by election at the next
meeting of the board of directors. Any officer may be removed from office with
or without cause at any time by the board of directors (but without prejudice to
the contractual rights, if any, of such officer with the Corporation).

                  SECTION 2. OTHER OFFICERS AND AGENTS. The board of directors
may elect or may delegate to the president authority to appoint one or more
assistant vice presidents, assistant treasurers, assistant secretaries and such
other officers and agents as may be advisable, who shall hold their offices for
such terms and shall exercise such powers and perform such duties as shall be
determined from time to time by the board of directors, or by the president in
the cases in which he shall have made the appointment.

                  SECTION 3. CHAIRMAN. The chairman of the board of directors,
if one is elected, shall preside at all meetings of the board of directors at
which he is present and shall have such powers and shall have and perform such
other duties as from time to time may be assigned to him by the board of
directors and as further provided in Section 4 of these by-laws.

                  SECTION 4. PRESIDENT. The president shall be the chief
executive officer of the Corporation, unless a chairman of the board is elected
as chief executive officer, in which case the president shall be the chief
operating officer of the

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Corporation. The president, and the chairman of the board, if one is elected,
shall have the general powers and duties of supervision and management vested in
the office of president of a corporation. The president shall preside at all
meetings of stockholders at which he is present, unless a chairman of the board
is elected and is present, in which case the chairman shall preside at such
meetings. The president shall have general supervision, direction and control of
the business of the Corporation, unless a chairman of the board is elected, in
which case the chairman shall have such general supervision, direction and
control in lieu of the president, and the president shall have supervision,
direction and control over the day-to-day affairs of the Corporation, unless
otherwise provided by the board of directors. Except as the board of directors
shall authorize the execution thereof in some other manner, the president, and
the chairman of the board, if one is elected, shall have the power to singly
execute bonds, mortgages and other contracts on behalf of the Corporation and
shall cause the seal of the Corporation to be affixed to any instrument
requiring it and when so affixed the seal shall be attested by the signature of
the secretary or the treasurer or an assistant secretary or an assistant
treasurer.

                  SECTION 5. VICE PRESIDENT. Each vice president shall have such
powers and shall have and perform such duties as from time to time may be
assigned to him by the board of directors.

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                  SECTION 6. TREASURER. The treasurer shall have the custody of
the corporate funds and securities and shall keep full and accurate account of
receipts and disbursements in books belonging to the Corporation. He shall
deposit all money and other valuables in the name and to the credit of the
Corporation in such depositaries as may be designated by the board of directors.
The treasurer shall disburse the funds of the Corporation as may be ordered by
the board of directors or by the president, taking proper vouchers for such
disbursements. He shall render to the president and board of directors at the
regular meetings of the board of directors, or whenever requested, an account of
all his transactions as treasurer and of the financial condition of the
Corporation. If required by the board of directors, he shall give the
Corporation a bond for the faithful discharge of his duties in such amount and
with such surety as the board of directors shall prescribe.

                  SECTION 7. SECRETARY. The secretary shall give, or cause to be
given, notice of all meetings of stockholders and directors, and all other
notices required by law or by these by-laws, and in case of his absence or
refusal or neglect so to do, any such notice may be given by any person
thereunto directed by the president, or by the directors, or by the
stockholders, upon whose requisition the meeting is called as provided in these
by-laws. He shall record all the proceedings of the meetings of the Corporation
and of the board of directors in a book to be kept for that purpose, and shall
perform such other duties as may

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be assigned to him by the board of directors or by the president. He shall have
the custody of the seal of the Corporation and shall affix the same to all
instruments requiring it, when authorized by the directors or by the president,
and shall attest the same.

                                    ARTICLE V

                                  CAPITAL STOCK

                  SECTION 1. CERTIFICATES OF STOCK. Certificates of capital
stock, numbered and with the seal of the Corporation affixed, signed by the
chairman of the board of directors, the president or a vice president, and by
the treasurer, an assistant treasurer, the secretary or an assistant secretary,
shall be issued to each stockholder certifying the number of shares of the
Corporation's capital stock owned by him. When such certificates are
countersigned by a transfer agent other than the Corporation or its employee, or
by a registrar other than the Corporation or its employee, the signatures of
such officers may be facsimiles.

                  SECTION 2. LOST CERTIFICATES. A new certificate of stock may
be issued in the place of any certificate theretofore issued by the Corporation,
and alleged to have been lost or destroyed, and the directors may, in their
discretion, require the owner of any lost or destroyed certificate, or his legal
representatives, to give the Corporation a bond, in such sum as they may direct,
to indemnify the Corporation against any claim that may be made against it on
account of the alleged loss or

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destruction of such certificate, or the issuance of any such new certificate.

                  SECTION 3. TRANSFER OF SHARES. The shares of stock of the
Corporation shall be transferable only upon its books by the holders thereof in
person or by their duly authorized attorneys or legal representatives, and upon
such transfer the old certificates shall be surrendered to the Corporation by
the delivery thereof to the person in charge of the stock transfer books and
ledgers, or to such other person as the board of directors may designate, by
whom they shall be cancelled, and new certificates shall thereupon be issued. A
record shall be made of each transfer and whenever a transfer shall be made for
collateral security, and not absolutely, it shall be so expressed in the entry
of the transfer.

                  SECTION 4. RECORD DATE. In order that the Corporation may
determine the stockholders entitled to notice of or to vote at any meeting of
stockholders or any adjournment thereof, or entitled to express consent to
corporate action in writing without a meeting, or entitled to receive payment of
any dividend or other distribution or allotment of any rights, or entitled to
exercise any rights in respect of any change, conversion or exchange of stock or
for the purpose of any other lawful action, the board of directors may fix, in
advance, a record date, which shall not be more than sixty nor fewer than ten
days before the date of such meeting, nor more than sixty days before any other
action. A determination of stockholders of record entitled to

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notice of or to vote at a meeting of stockholders shall apply to any adjournment
of the meeting; provided, however, that the board of directors may fix a new
record date for the adjourned meeting.

                  SECTION 5. DIVIDENDS. Subject to the provisions of the
certificate of incorporation, the board of directors may, out of funds legally
available therefor at any regular or special meeting, declare dividends upon the
capital stock of the Corporation as and when they deem expedient. Before
declaring any dividend there may be set apart out of any funds of the
Corporation available for dividends such sum or sums as the board of directors
from time to time in its discretion may deem proper for working capital or as a
reserve fund to meet contingencies or for equalizing dividends or for such other
purposes as the board of directors shall deem conducive to the interests of the
Corporation.

                                   ARTICLE VI

                                 INDEMNIFICATION

         The corporation shall (a) indemnify any person who was or is a party or
is threatened to be made a party to any threatened, pending or completed action
or suit by or in the right of the Corporation to procure a judgment in its favor
by reason of the fact that he is or was a director or officer of the
Corporation, or is or was serving at the request of the Corporation as a
director, officer, employee or agent of another corporation, partnership, joint
venture, trust or other enterprise, against

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expenses (including attorneys' fees) actually and reasonably incurred by him in
connection with the defense or settlement of such action or suit, and (b)
indemnify any person who was or is a party or is threatened to be made a party
to any threatened, pending or completed action, suit or proceeding, whether
civil, criminal, administrative or investigative (other than an action by or in
the right of the Corporation), by reason of the fact that he is or was a
director or officer of the Corporation, or served at the request of the
Corporation as a director, officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise, against expenses
(including attorneys' fees), judgments, fines and amounts paid in settlement
actually and reasonably incurred by him in connection with any such action, suit
or proceeding, in each case to the fullest extent permissible under Section 145
of the General Corporation Law of the State of Delaware or the indemnification
provisions of any successor statute. The foregoing right of indemnification
shall in no way be exclusive of any other rights of indemnification to which any
such person may be entitled, under any by-law, agreement, vote of stockholders
or disinterested directors or otherwise, and shall inure to the benefit of the
heirs, executors and administrators of such a person.

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                                   ARTICLE VII

                                     GENERAL

                  SECTION 1. SEAL. The seal of the Corporation shall be circular
in form and shall contain the name of the Corporation, the year of its
organization and the words "CORPORATE SEAL, DELAWARE". The seal may be used by
causing it or a facsimile thereof to be impressed or affixed or otherwise
reproduced.

                  SECTION 2. FISCAL YEAR. The fiscal year of the Corporation
shall be determined by resolution of the board of directors.

                  SECTION 3. CHECKS. All checks, drafts or other orders for the
payment of money, notes or other evidences of indebtedness issued in the name of
the Corporation shall be signed by such officer or officers, agent or agents of
the Corporation and in such manner as shall be determined from time to time by
resolution of the board of directors.

                  SECTION 4. NOTICE AND WAIVER OF NOTICE. Whenever any notice
is required by these by-laws to be given, personal notice is not meant unless
expressly so stated, and any notice so required shall be deemed to be sufficient
if given (a) orally or in any other manner to directors in sufficient time to
permit their convenient assembly and (b) in writing by cable, telex, facsimile
transmission or mail to stockholders. Depositing such notice in the United
States mails, postage prepaid, addressed to the person entitled thereto at his
address as it appears on the records of the Corporation, shall be deemed to give
notice on the

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day of such mailing. Whenever any notice whatever is required to be given under
the provisions of any law, or under the provisions of the certificate of
incorporation or these by-laws, a waiver thereof in writing, signed by the
person or persons entitled to said notice, whether before or after the time
stated therein, shall be deemed equivalent thereto. Attendance at a meeting
shall constitute a waiver of notice, except attendance for the purpose of
objecting to the convening of the meeting, when objection is expressed at the
beginning of the meeting.

                                  ARTICLE VIII

                                   AMENDMENTS

         These by-laws may be altered or repealed and by-laws may be made at any
annual meeting of stockholders, or at any special meeting thereof if notice of
the proposed alteration or repeal or of the by-laws to be made is contained in
the notice of such special meeting, by the affirmative vote of the holders of a
majority of the stock issued and outstanding and entitled to vote thereat, or by
the affirmative vote of a majority of the board of directors at any regular
meeting of the board of directors, or at any special meeting of the board of
directors if notice of the proposed alteration or repeal or of the by-laws to be
made is contained in the notice of such special meeting.

Date: June 25, 1997

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