1. The Rogoff-Wellcome Medical Res. Inst., Medical School, Beilinson Hospital, Petah-Tikva, Israel
2. Inst. of Molecular Biology, Natl. Tsing Hua Univer., Hsinchu, Taiwan
3. Section of Pharmacol. and Toxicol., Univer. of Connecticut, School of Pharmacy, Storrs, Ct., U.S.A.