Funding for this research was provided by:
China Pharmaceutical University (3150120001)
Text and Data Mining valid from 2019-01-11
Received: 19 October 2017
Accepted: 28 December 2018
First Online: 11 January 2019
Ethics approval and consent to participate
: Ethical approval was waived since we used only publicly available data and materials in this study.
: Not applicable.
: The authors declare that they have no competing interests.
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