1. Department of Geriatrics and Special Service Medicine, Southwest Hospital, Army Military Medical University (Third Military Medical University), 400038 Chongqing, China
2. Department of Neurosurgery, the Affiliated Huaihai Hospital of Xuzhou Medical University 221000 Xuzhou China
3. Department of Infectious Diseases, Southwest Hospital, Army Military Medical University (Third Military Medical University), 400038 Chongqing, China
4. Department of Respiratory Medicine, Southwest Hospital, Army Military Medical University (Third Military Medical University), 400038 Chongqing, China