1. Laboratory of Comparative Carcinogenesis, National Cancer Institute at Frederick, P.O. Box B, Building 538, Frederick, Maryland 21702, Departments of Cellular and Molecular Physiology and Pharmacology, The Pennsylvania State University College of Medicine, P.O. Box 850, Hershey, Pennsylvania 17033, Department of Chemistry and Center for Molecular Diversity in Drug Design, Discovery, and Delivery, University of South Florida, Tampa, Florida 33620, and Drug Discovery Program, H. Lee Moffitt Cancer Center &...