1. Blood Research Laboratory, Pratt Clinic-New England Center Hospital, and the Department of Medicine, Tufts University School of Medicine, Boston, Mass.
2. Blood Research Laboratory, Pratt Clinic-New England Center Hospital, and Instructor in Medicine, Tufts University School of Medicine, Boston, Mass.
3. Blood Research Laboratory, Pra4i Clinic-New England Center Hospital, and Assistant Professor of Medicine, Tufts University School of Medicine, Boston, Mass.
4. New England Medical Center Hospitals, and Professor of Medicine, Tufts University School of Medicine, Boston, Mass.