1. The first people's Hospital of Hefei, 390 N. Huaihe Road, Luyang District, Hefei, 230061, China
2. Department of Epidemiology and Health Statistics, School of Public Health Anhui Medical University, No. 81 Meishan Road, Hefei 230032, Anhui, P.R. China.
3. Department of Orthopedics, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, 524001, China
4. Department of Dentistry and Oral and Maxillofacial Surgery, Columbia University Irving Medical Center, 622W 168th St, New York, NY 10032, USA
5. Internal Medicine, Swedish Hospital, 5140 N California Ave, Chicago, IL 60625, USA
6. Infectious disease and international health, Dartmouth-Hitchcock Medical Center, 1 Medical Center Drive, Lebanon NH 03756, USA
7. Department of Thyroid and Breast Surgery, The Second Hospital of Anhui Medical University, Furong Road 678, Hefei 230601, China.