1. People’s Hospital of Dingxi City, The Second Affiliated Hospital of Lanzhou University Medical School, Dingxi, China
2. College of Clinical Medicine, Lanzhou University Medical School, Lanzhou, China
3. College of Graduate Studies, Kunming Medical University, Kunming, China
4. College of Mathematics, Honghe University, Mengzi, Yunnan, China
5. Department of Radiology, Affiliated Hospital of Yunnan University, Kunming, China