Funding for this research was provided by:
National Natural Science Foundation of China (31570635, 31500431, 31270535)
Outstanding Youth Science Foundation of Heilongjiang Province (JC201306)
Text and Data Mining valid from 2018-11-21
Received: 31 January 2018
Accepted: 19 October 2018
First Online: 21 November 2018
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: The authors declare that they have no competing interests.
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