[1] Rongchang Dist Maternal & Child Hlth Care Ctr Cho, Dept Clin Lab, Chongqing 402460, Peoples R China
[2] Rongchang Dist Peoples Hosp Chongqing, Dept Obstetr & Gynecol, Chongqing 402460, Peoples R China
[3] Rongchang Dist Peoples Hosp Chongqing, Dept Digest, 3 North Plaza Rd, Chongqing 402460, Peoples R China
[4] Army Mil Med Univ, Dept Neurosurg, Hosp 1, Southwest Hosp, Chongqing 400000, Peoples R China
[5] North Sichuan Med Coll, Dept Digest, Affiliated Hosp, 63 Wenhua Rd, Nanchong 637000, Sichuan, Peoples R China