Funding for this research was provided by:
National Natural Science Foundation of China (NSFC81871585)
Natural Science Foundation of Guangdong Province (2018A030313058)
Article History
Received: 6 March 2019
Accepted: 2 May 2019
First Online: 17 May 2019
Ethics approval and consent to participate
: This study is a systematic review and meta-analysis, and ethics approval and consent to participate are not available.
: Not available.
: The authors declare that they have no competing interests.
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