[1] Chongqing Med Univ, Affiliated Hosp 1, Dept Thorac Surg, Chongqing 400016, Peoples R China
[2] Chongqing Med Univ, Affiliated Hosp 1, Dept Obstet & Gynaecol, Chongqing 400016, Peoples R China
[3] Chongqing Med Univ, Affiliated Hosp 1, Dept Gastrointestinal Surg, Chongqing 400016, Peoples R China
[4] Chongqing Med Univ, Affiliated Hosp 1, Dept Obstet & Gynaecol, 1 Youyi Rd,Yuanjiagang St, Chongqing 400016, Peoples R China