Funding for this research was provided by:
National Natural Science Foundation of China (11804199, 11704231)
China Postdoctoral Science Foundation (2017M622252)
Text and Data Mining valid from 2019-05-07
Received: 1 February 2019
Accepted: 26 April 2019
First Online: 7 May 2019
: The authors declare that they have no competing interests.
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