1. Graduate School of Peking Union Medical College, Beijing 100730, China
2. Department of Gastroenterology, China-Japan Friendship Hospital, Beijing 100029, China
3. Department of Infection, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
4. School of Qi Huang, Beijing University of Chinese Medicine, Beijing 100029, China
5. Beijing University of Chinese Medicine, Beijing 100029, China