Funding for this research was provided by:
National Natural Science Foundation of China (81370128)
Natural Science Foundation of Hainan Province (14JJ2028)
Text and Data Mining valid from 2018-08-20
Received: 2 May 2018
Accepted: 7 August 2018
First Online: 20 August 2018
: Ethical approval, all applicable international, national, and/or institutional guidelines for the care and use of animals were followed.
: Not applicable.
: The authors declare that they have no competing interests.
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