1. Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of H Bethesda, MD 20892.
2. Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892.
3. Laboratory of Mathematical Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892.
4. Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda MD 20892.
5. Metabolism Branch, National Institutes of Health, Bethesda, MD 20892.