Funding for this research was provided by:
National Natural Science Foundation of China (31872516)
the National Key Technology Research and Development Program of China (2015BAD11B00)
the National Key Research and Development Program of China (2018YFD0500302)
Text and Data Mining valid from 2019-04-02
First Online: 2 April 2019
Compliance with Ethical Standards
: The authors declare that they have no competing interests.