Affiliation: | 1. M.E. Mueller Institute for Microscopy, Biozentrum, University of Basel, Klingelbergstrasse 70, CH-4056 Basel, Switzerland;2. Friedrich Miescher Institut, PO Box 2543, CH-4002 Basel, Switzerland;1. Wadsworth Center, New York State Department of Health, P.O. Box 22002, Albany, NY 12201-2002, USA |