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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(AMENDMENT NO. 2)*
NORTH AMERICAN SCIENTIFIC, INC.
(Name of Issuer)
Common Stock
(Title of Class of Securities)
65715D100
(CUSIP Number)
*The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which
would alter the disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities Exchange
Act of 1934 ("Act") or otherwise subject to the liabilities of that section
of the Act but shall be subject to all other provisions of the Act (however,
see the Notes).
Page 1 of 4 pages
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SCHEDULE 13G
CUSIP NO. 65715D100 PAGE 2 OF 4 PAGES
------------- --- ---
_____________________________________________________________________________
1 NAME OF REPORTING PERSON
S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Irwin J. Gruverman
_____________________________________________________________________________
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) / /
(b) /X/
_____________________________________________________________________________
3 SEC USE ONLY
_____________________________________________________________________________
4 CITIZENSHIP OR PLACE OF ORGANIZATION
U.S.
_____________________________________________________________________________
5 SOLE VOTING POWER
296,500*
__________________________________________________________
6 SHARED VOTING POWER
0
NUMBER OF __________________________________________________________
SHARES
BENEFICIALLY 7 SOLE DISPOSITIVE POWER
OWNED BY
EACH 296,500*
REPORTING __________________________________________________________
PERSON
WITH 8 SHARED DISPOSITIVE POWER
0
_____________________________________________________________________________
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH
REPORTING PERSON
296,500*
_____________________________________________________________________________
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* /X/
_____________________________________________________________________________
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
6.98%
_____________________________________________________________________________
12 TYPE OF REPORTING PERSON*
IN
_____________________________________________________________________________
* Includes 19,000 shares held in a fund of which the reporting person is the
sole general partner, 50,000 shares subject to outstanding options which are
currently exercisable and 5,000 shares subject to outstanding options which
are exercisable March 28, 1998. Excludes 20,000 shares owned by reporting
person's spouse, as to which reporting person disclaims beneficial ownership.
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ITEM 1 (a) Name of Issuer: North American Scientific, Inc.
ITEM 1 (b) Address of Issuer's Principal Executive Offices:
7435 Greenbush Avenue,
North Hollywood, CA 91605
ITEM 2 (a) Name of Person Filing: Irwin J. Gruverman
ITEM 2 (b) Address of Principal Business Office:
30 Ossipee Road
Newton, MA 02464
ITEM 2 (c) Citizenship: United States
ITEM 2 (d) Title of Class of Securities:
Common Stock, $0.01 par value
ITEM 2 (e) CUSIP Number: 65715D100
ITEM 3 Not Applicable.
ITEM 4 Ownership:
The following information is provided as of December 31, 1997:
(a) Amount Beneficially Owned: 296,500*
(b) Percent of Class: 6.98%
(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote: 296,500*
(ii) shared power to vote or to direct the vote: 0
(iii) sole power to dispose or to direct the disposition
of: 296,500*
(iv) shared power to dispose or to direct the
disposition of: 0
* Includes 19,000 shares held in a fund of which the reporting person is the
sole general partner, 50,000 shares subject to outstanding options which are
immediately exercisable and 5,000 shares subject to outstanding options which
are exercisable March 28, 1998. Excludes 20,000 shares owned by reporting
person's spouse, as to which reporting person disclaims beneficial ownership.
Page 3 of 4 pages
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ITEM 5 Ownership of Five Percent or Less of a Class:
Not Applicable
ITEM 6 Ownership of More than Five Percent on Behalf of Another Person:
Not Applicable
ITEM 7 Identification and Classification of the Subsidiary Which
Acquired the Security Being Reported on by the Parent Holding
Company:
Not Applicable.
ITEM 8 Identification and Classification of Members of the Group:
Not Applicable.
ITEM 9 Notice of Dissolution of Group:
Not Applicable.
ITEM 10 Certification:
Not Applicable.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete
and correct.
Date: February 2, 1998
Signature: /s/ Irwin J. Gruverman
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Name/Title: Irwin J. Gruverman
Page 4 of 4 pages
