1 State Key Laboratory of Biotherapy of China, Division of Pulmonary Diseases, West China Hospital of Sichuan University, Chengdu, China.
2 Department of Gastroenterology, West China Hospital of Sichuan University, Chengdu, China.
3 First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
4 Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States.