1. Department of Respiratory Medicine, Lianshui County People's Hospital, Kangda College of Nanjing Medical University, Huai'an, Jiangsu 223400, P.R. China
2. Department of Radiotherapy, Lianshui County People's Hospital, Kangda College of Nanjing Medical University, Huai'an, Jiangsu 223400, P.R. China
3. Clinical Laboratory, Lianshui County People's Hospital, Kangda College of Nanjing Medical University, Huai'an, Jiangsu 223400, P.R. China