1 Department of Gastroenterology, The Affiliated Nanjing Drum Tower Hospital of Medical School of Nanjing University, Zhongshan Road No. 231, Nanjing 210000, China.
2 Department of Gastroenterology, The Affiliated Nanjing Drum Tower Hospital of Medical School of Nanjing University, Zhongshan Road No. 231, Nanjing 210000, China. Electronic address: springpcy@aliyun.com.