Arthritis & Rheumatism Official Journal of the American College of Rheurnatology Editor Peter H. Schur, MD Room 441, Richardson Fuller Building 221 Longwood Avenue Boston, M A 02115 Associate Editors K. Frank Austen, MD, Boston Laurie H. Glimcher, MD, Boston Don L. Goldenberg, MD, Boston Robert A. Lew, PhD, Boston Matthew H, Liang, MD, MPH, Boston Dwight R. Robinson, MD, Boston Clement B. Sledge, MD, Boston Michael E. Weinblatt, MD, Boston Barbara N. Weissman, MD, Boston Committee for the Publication of A&R H. Ralph Schumacher, MD, Chair, Philadelphia Philip L. Cohen, MD, Chapel Hill Bruce N. Cronstein, MD, New York David A. Fox, MD, Ann Arbor Gary S. Hoffman, MD, Cleveland Carolyn L. Yancey, MD, Landover Editoriai Staff Jane S. Diamond, MPH, Managing Editor, Atlanta Patricia K. Higgins, Assistant Managjng Editor, Atlanta Catherine I. Morlino, Editorial Assistant, Boslon Elisa C. Schulz, Prodi~c~ion Editor, Philadelphia Editorial Board Steven B. Abramson, MD, New York Carlos A. Agudelo, MD, Atlanta Donato Atarcon-Segovia, MD, Mexico City Gene V. Ball, MD, Birmingham Anders 0. Bjelle, MD, Giiteborg Stefano Bombardieri, MD, Pisa Ferdinand C. Breedveld, MD, Leiden Constance E. Brinckerhoff, PhD, Hanover Peter Brooks, MD, FRACP, Sydney Gerd R. Ehrmester, MD, Erlangen Jill P. Buyon, MD, New York Grant W. Cannon, MD, Salt Lake City Sheldon Cooper, MD, Burlington Gary S. Firestein, MD, Sun Diego Mary B. Goldring, PhD, Boston Ellen M. IGravallese, MD, Boston Arthur P. Hall, MD, Boston John B. Harley, MD, PhD, Oklahoma City Louis W. Heck, Jr., MD, Birmingham Marilyn C. Pike, MD, PhD, Boston Jordan S. Pober, MD, PhD, Boston Richard M. Pope, MD, Chicago Tadamitsu Kishimoto, MD, PhD, Osaka Rosalind Ramsey-Goldman, MD, DrPH, Chicago Klaus E. Kuettner, PhD, Chicago Naomi F. Rothfield, MD, Farmington Ravinder N. Maini, MD, London James R. Seibold, MD, New Brunswick S. Spence McCachren, MD, Durham Leonard H. Sigal, MD, New Brunswick Charles J. Menkes, MD, Paris Leon Sokoloff, MD, Stony Brook Pierre Miossec, MD, PhD, Lyon Alan M. Solinger, MD, Sun Diego John Mort, PhD, Montreal Haralampos M. Moutsopoulos, MD, Zoannina Virginia D. Steen, MD, Pittsburgh Ronald P. Taylor, PhD, Charlottesville Jacob B. Natvig, MD, Oslo Robert Terkeltaub, MD, Sun Diego Barbara W. Needleman, MD, Baltimore Daniel E. Tracey, PhD, Cambridge Barbara S. Nepom, MD, Seattle Patience H. White, MD, Washington Gerald T. Nepom, MD, PhD, Seattle H. James Wiliams, MD, Salt Lake City Nancy J. Olsen, MD, Nashville J. Frederick Woessner, PhD, Miami Gabriel S. Panayi, MD, MRCP, London Morris Zfi, PhD, MD, Dallas Christine Parker, MD, PhD, Boston Harold E. Paulus, MD, Los Angeles Jean-Pierre Pelletier, MD, Montreal Gunnar Husby, MD, Oslo James H. Kimura, PhD, Chicago AMERICAN COLLEGE OF RHEUMATOLOGY Herbert Kaplan, MD, Denver, President Shaun Ruddy, MD, Richmond, First Vice-president and President-Elect Arthur L. Weaver, MD, Lincoln, Second Vice-president William J. Koopman, MD, B~rmingham,Treasurer Ronald L. Kaufman, MD, MBA, Los Angeles, Secretary Mark Andrejeski, Atlanta, Executive V i c ~ - ~ e s i d e n t Published for the College by J. B. ~ i p p i n ~ oCompany tt Arfhrj~jsC% R h e u ~ u r i (ISSN s~ 0004-3591) is pubIishe~monthly for the American College of Rheumatology by J. B. Lippincott Company, at 12107 Insurance Way, Suite 114, Suite 114, Hagerstown, MD 21740. Business offices are located at 227 East Washington Square, P~adelphia,PA 19106. Printed in the U.S.A. Copyright 1994 by the American College of Rheumatology, Atlanta, Georgia. Printed on acid-free paper effective with volume 32, number 11. Second class postage paid at Hagerstown, Maryland, and additional offices. Subscription information, orders, or nonmember changes of address: (except Japan) 12107 Insurance Way, Suite 114, Hagerstown, MD 21740, or call 1-800-638-3030;in Maryland, call collect 301-714-2300. 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