1. College of Basic Medical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, P. R. China
2. Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, P. R. China
3. Gastroenterology of Chinese Medicine, Tongde Hospital of Zhejiang Province, Hangzhou 310007, P. R. China
4. Department of Anesthesiology, Affiliated Hospital of Shandong, University of Traditional Chinese Medicine, Jinan 250014, P. R. China