Funding for this research was provided by:
Guangdong Province Science and Technologue Program (No. 2011B031800386)
Article History
Received: 14 August 2017
Accepted: 27 December 2017
First Online: 25 January 2018
Compliance with ethical standards
:
: We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted.
: The Ethics Committee of The Third Affiliated Hospital of Southern Medical University, Guangzhou, approved this study. This study was performed fulfilling the principles of Helsinki Declaration.
: Informed consent was obtained from all participants included in the study.