Sun, Yanchun
Yang, Zheng
Wan, Chonghua
Xu, Chuanzhi
Chen, Liuping
Xu, Lin
Zhang, Xiaoqing
Yan, Fei
Funding for this research was provided by:
the National Natural Science Foundation of China (71373058)
the National Natural Science Foundation of China (30860248)
the Science and Technological Planning Program of Guangdong Province (2013B021800074)
Article History
Received: 5 January 2018
Accepted: 25 June 2018
First Online: 11 July 2018
Ethics approval and consent to participate
: The study protocol was approved by the Institutional Review Board of the investigators’ institutions. The respondents were anonymous, voluntary and provided consent for participation.
: No individual’s personal data has been included.
: The authors declare that they have no competing interests.
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