1. State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica; Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing 100050 P. R. China
2. College of Pharmacy; Liaoning University of Traditional Chinese Medicine; Dalian 116620 P. R. China
3. Inner Mongolia Pharmaceutical Industrial Institute Co. Ltd; Hohhot 010010 China
4. Inner Mongolia Medical College; Hohhot 010059 China