1. Department of Laboratory Medicine, Chongqing University Cancer Hospital and Chongqing Cancer Institute and Chongqing Cancer Hospital, Chongqing 400030, P.R. China
2. Department of Gastroenterology, Chongqing General Hospital, Chongqing 400014, P.R. China
3. Medical Center of Stomatology, The Second Clinical Medical College, Jinan University, Shenzhen People's Hospital, Shenzhen, Guangdong 518020, P.R. China
4. Clinical Medical Research Center, The Second Clinical Medical College, Jinan University, Shenzhen People's Hospital, Shenzhen, Guangdong 518020, P.R. China