[1] Third Peoples Hosp Zigong, Dept Hematol & Oncol, Zigong 643000, Sichuan, Peoples R China
[2] First Peoples Hosp Zigong, Dept Pulm & Crit Care Med, 42 Shangyihao Yizhi St, Zigong 643000, Sichuan, Peoples R China
[3] North Sichuan Med Coll, Nanchong 637100, Sichuan, Peoples R China
[4] Fourth Peoples Hosp Zigong, Dept Neurosurg, Zigong 643000, Sichuan, Peoples R China
[5] Sichuan Univ, West China Hosp 2, Dept Obstet & Gynecol, Chengdu 610000, Sichuan, Peoples R China