Affiliation: | 1. Cancer Research Institute and the Departments of Pharmacology, University of California at San Francisco, San Francisco, CA 94143 U.S.A.;2. Departments of Pharmacology, University of California at San Francisco, San Francisco, CA 94143 U.S.A.;3. Departments of Pharmacy and Pharmaceutical Chemistry, University of California at San Francisco, San Francisco, CA 94143 U.S.A.;4. Department of Microbiology, University of Illinois, Champaign Urbana, IL 61801 U.S.A. |