Funding for this research was provided by:
Guangdong Medical Research Foundation (B2013008)
National Office for Philosophy and Social Sciences (CN) (81401689)
the Natural Science Foundation of Guangdong Province, China (2014A030310228)
Text and Data Mining valid from 2019-07-31
Received: 11 April 2019
Accepted: 22 July 2019
First Online: 31 July 2019
Ethics approval and consent to participate
: Written informed consent was obtained from each participant before the commencement of this study, and The Human Research Ethics Committee from Guangzhou University of Chinese Medicine and Sun Yat-sen University approved all aspects.
: All authors consent to the publication of this manuscript.
: The authors declare that they have no competing interests.