1. Department of Neonatology, Yichang Maternal and Child Health Care Hospital, Clinical Medical College of Women and Children, Three Gorges University, Yichang, China
2. Department of Pediatrics, Yichang Maternal and Child Health Care Hospital, Clinical Medical College of Women and Children, Three Gorges University, Yichang, China
3. Ultrasonographic Department, Yichang Maternal and Child Health Care Hospital, Clinical Medical College of Women and Children, Three Gorges University, Yichang, China
4. Department of Science and Education, Yichang Maternal and Child Health Care Hospital, Clinical Medical College of Women and Children, Three Gorges University, Yichang, China
5. Department of Neonatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China