1. Department of Neurology; West China Hospital; Sichuan University; Chengdu Sichuan P.R. China
2. Department of Neurology; National Neuroscience Institute; Singapore General Hospital; Singapore Singapore
3. Duke-NUS Graduate Medical School; Singapore Singapore
4. Department of Internal Medicine; Wangjiang Hospital; Sichuan University; Chengdu Sichuan P.R. China