1. College of Medicine, Southwest Jiaotong University, Chengdu, Sichuan, China
2. The General Hospital of Western Theater Command, Chengdu, Sichuan, China
3. Chengdu Eighth People’s Hospital (Geriatric Hospital of Chengdu Medical College), Chengdu, Sichuan, China
4. North Sichuan Medical College, Nanchong, Sichuan, China
5. Medical Transformation Center of Southwest Jiaotong University, Chengdu, Sichuan, China.