Medical Progress

From the Departments of Medicine and Pathology, Washington University School of Medicine, St. Louis (L.T.G.); the Departments of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill (M.E.B.); the Department of Pathology, Southern California Permanente Medical Group, Woodland Hills, Calif. (M.H.K.); and the Department of Pathology, Dartmouth-Hitchcock Medical Center, Lebanon, N.H. (J.P.A.). Address reprint requests to Dr. Goodnough at Washington University School of Medicine, Division of Laboratory Medicine, Box 8118, 660 S. Euclid Ave., St. Louis, MO 63110-1093.