1. Department of Radiology; The First Hospital of Lanzhou University; Lanzhou Gansu P.R. China
2. The First Clinical Medical College of Lanzhou University; Lanzhou; Gansu P.R. China
3. Department of Medical Oncology; The First Hospital of Lanzhou University; Lanzhou Gansu P.R. China
4. Department of Respiratory Medicine; The First Hospital of Lanzhou University; Lanzhou Gansu P.R. China