1. Leukemia Service, Medicine Branch, and Human Tumor Cell Biology Branch, National Cancer Institute, Bethesda, Md., and the Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, Bethesda, Md.
2. Leukemia Service, Medicine Branch, National Cancer Institute, Bethesda, Md.
3. Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, Bethesda, Md.
4. Human Tumor Cell Biology Branch, National Cancer Institute, Bethesda, Md.