[1] Qingdao Univ, Thorac Surg Dept, Affiliated Municipal Hosp, 1 Jiaozhou Rd, Qingdao 266011, Shandong, Peoples R China
[2] Qingdao Univ, Affiliated Municipal Hosp, 25 Donghai Middle Rd, Qingdao 266071, Shandong, Peoples R China
[3] Qingdao Univ, Affiliated Hosp, 16 Jiangsu Rd, Qingdao 266003, Shandong, Peoples R China
[4] Qingdao Univ, Sch Nursing, 15 Ningde Rd, Qingdao 266071, Shandong, Peoples R China