1. Medical Imaging Center, Gansu Provincial Maternity and Child-care Hospital, Lanzhou, China;
2. Department of Respiratory Medicine, The 940th Hospital of the Joint Logistic Support Force of the Chinese People's Liberation Army (Former Lanzhou General Hospital of Lanzhou Military Region), Lanzhou, China;
3. Otolaryngology Head and Neck Surgery, Gansu Provincial Maternity and Child-care Hospital, Lanzhou, China;
4. Functional Examination Department, Gansu Provincial Maternity and Child-care Hospital, Lanzhou, China;
5. Nuclear Magnetic Resonance Chamber, Lanzhou University Second Hospital, Lanzhou, China