1. Department of Gastroenterology, Affiliated Nanhua Hospital, University of South China, Hengyang, Hunan, PR China
2. Department of Gastroenterology, The First People's Hospital of Chenzhou, Chenzhou, Hunan, PR China
3. Key Laboratory for Quality Evaluation of Bulk Herbs of Hunan Province, School of pharmacy, Hunan University of Chinese Medicine, Changsha, Hunan, China