1. Department of Thoracic Surgery, Hebei General Hospital, Children's Hospital of Hebei Province, Shijiazhuang, Hebei 050000, P.R. China
2. Department of Thoracic Surgery, Hebei General Hospital, Children's Hospital of Hebei Province, Shijiazhuang, Hebei 050000, P.R. China
3. Department of Pathology, Hebei General Hospital, Children's Hospital of Hebei Province, Shijiazhuang, Hebei 050000, P.R. China