Funding for this research was provided by:
National Natural Science Foundation of China (71601081, 71571073)
Natural Science Foundation of Guangdong Province (2016A030310426)
Fundamental Research Funds for the Central Universities (2017BQ048)
Text and Data Mining valid from 2018-06-11
First Online: 11 June 2018
Compliance with ethical standards
: On behalf of all authors, the corresponding author states that there is no conflict of interest.