1. Department of Clinical Medicine, Weifang Medical University, Weifang, Shandong, China;
2. Department of Respiratory Medicine, Shandong Provincial Qianfoshan Hospital affiliated to Shandong University, Jinan, Shandong, China;
3. Department of MR, Shandong Medical Imaging Research Institute, Shandong University, Jinan, Shandong, China;
4. Department of Respiratory Medicine, The Second Affiliated Hospital of Shandong First Medical University, Taian, Shandong, China;
5. Medical Research Center, Shandong Provincial Qianfoshan Hospital affiliated to Shandong University, Jinan, Shandong, China