1. Department of Pediatrics, The First Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu Province, China
2. Grade 2013 Clinical Class 7, The First School of Clinical Medicine, Nanjing Medical University, Nanjing, Jiangsu Province, China
3. Department of Pediatric Respiration, Affiliated Wuxi People's Hospital, Nanjing Medical University, Wuxi, Jiangsu, China