1. Department of Radiation Oncology, The First Hospital of Lanzhou University, Lanzhou, Gansu, PR China
2. The First Clinical Medical College of Lanzhou University, Lanzhou, PR China
3. Clinical Skills Center of Yantai Affiliated Hospital of Binzhou Medical College, Yantai, PR China
4. Department of Oncology Surgery, The First Hospital of Lanzhou University, Lanzhou, Gansu, PR China