1. Department of Gastroenterology, the People’s Hospital of Rizhao, Rizhao, Shandong Province, China
2. Department of Gastroenterology, the Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
3. Department of Pathology, the Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
4. Department of Nutriology, the Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China.