1. Chinese Medicine Laboratory, Hong Kong Jockey Club Institute of Chinese Medicine, Hong Kong, P. R. China, Departments of Pathology and Pediatrics, Center for Complementary Medicine Research, Child and Family Research Institute, University of British Columbia, Vancouver, BC, Canada, and State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, Yunnan, P. R. China