1. Department of Anesthesiology, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
2. Department of Pediatric Surgery, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
3. Department of Pathology, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China.