1. National Institute of Arthritis & Metabolic Diseases and The Clinical Center, National Institutes of Health, Bethesda, Md.
2. Laboratory of Experimental Pathology, National Institutes of Arthritis and Metabolic Diseases, National Institutes of Health, Bethesda, Md.
3. Hematology Service, Clinical Pathology Department, Clinical Center National Institutes of Health, Bethesda, Md.