[1]Zhejiang Univ, Sch Med, Affiliated Hosp 2, Hangzhou, Zhejiang, Peoples R China.
[2]Jiangsu Prov Hosp, Nanjing, Jiangsu, Peoples R China.
[3]Shanghai Jiao Tong Univ, Sch Med, Ren Ji Hosp, Shanghai 200030, Peoples R China.
[4]Chinese Peoples Liberat Army Gen Hosp, Beijing 100853, Peoples R China.
[5]Second Mil Med Univ, Changhai Hosp, Shanghai, Peoples R China.
[6]Hangzhou First Peoples Hosp, Hangzhou, Zhejiang, Peoples R China.
[7]Lanzhou Univ, Hosp 1, Lanzhou 730000, Peoples R China.
[8]Shanxi Coal Cent Hosp, Taiyuan, Shanxi, Peoples R China.
[9]Nanchang Univ, Affiliated Hosp 1, Nanchang, Jiangxi, Peoples R China.
[10]Chongqing Med Univ, Affiliated Hosp 2, Chongqing, Peoples R China.
[11]China Med Univ, Shengjing Hosp, Shenyang, Liaoning, Peoples R China.
[12]Editorial Off Chinese Journal Digest Endoscopy, Beijing, Peoples R China.
[13]Shanghai Gen Hosp, Shanghai, Peoples R China.
[14]Jilin Univ, Hosp 1, Changchun, Jilin, Peoples R China.
[15]Anhui Med Univ, Affiliated Hosp 1, Hefei, Anhui, Peoples R China.
[16]Huazhong Univ Sci & Technol, Tongji Hosp, Tongji Med Coll, Wuhan, Peoples R China.