1. Clinical Pathology Department, Warren Grant Magnuson Clinical Center, Digestive Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, and Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
2. Current address: Robert W. Woodruff Health Sciences Center, Emory University School of Medicine, Atlanta, GA 30322
3. Current address: Department of Internal Medicine, St. Louis University Health Sciences Center, 1402 South Grand Blvd., St. Louis, MO 63104