1Department of Gastroenterology, The Third Xiangya Hospital of Central South University, Hunan, China;

2Department of Gastroenterology, The Xiangtan First People's Hospital, Hunan, China.

Correspondence: Li Tian, MD, PhD. E-mail: [email protected]. Ying Zhong, MM. E-mail: [email protected].

*Mingmei Ye and Quanheng Liu contributed equally to this work.