1. School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
2. School of Public Health, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
3. Department of Cardiology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510260, P.R. China
4. Guangdong Second Provincial General Hospital, Guangzhou, Guangdong 510317, P.R. China