Funding for this research was provided by:
National Natural Science Foundation of China (81460331, 81560349, 81660457)
Text and Data Mining valid from 2018-04-03
Received: 15 January 2018
Accepted: 16 March 2018
First Online: 3 April 2018
Ethics approval and consent to participate
: Not applicable. This meta-analysis does not involve research on humans.
: Not applicable.
: The authors declare that they have no competing interests.
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