1. Section of Hematology, Department of Medicine, Brookdale Medical Hospital Center, Brooklyn, N.Y.
2. Section of Hematology, Department of Medicine, Brookdale Hospital Medical Center, Brooklyn, N. Y.
3. Division of Hematology, Department of Medicine, Kingsbrook Jewish Medical Center, Brooklyn, N.Y.; formerly Fellow in Hematology, Brookdale Hospital Medical Center, Brooklyn, N.Y.
4. Orentreich Foundation for the Advancement of Science, New York, N.Y.