1. From the Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis (J.J.Y., M.G.M., G.F.); the Department of Pathology, Abbott–Northwestern Hospital, Minneapolis (M.A.A.); the Department of Biometry, University of Minnesota School of Public Health, Minneapolis (D.P.A.); and the Department of Medicine, Veterans Administration Medical Center, Minneapolis (M.M.O.). Address reprint requests to Dr. Yunis at the University of Minnesota Medical School, Box 198 UMHC,...