1. The Second Department of Cardiology, Shouguang City People's Hospital, Weifang, Shandong 262700, P.R. China
2. Dongcheng Branch of Shouguang People's Hospital, Weifang, Shandong 262700, P.R. China
3. Department of Orthopedics, Shouguang City People's Hospital, Weifang, Shandong 262700, P.R. China