Funding for this research was provided by:
Natural Science Foundation of Liaoning Province (20180550863, 2015020806)
the Fundamental Research Funds for the Central Universities (XDJK2018AA002)
Text and Data Mining valid from 2019-03-28
Received: 19 January 2019
Accepted: 22 February 2019
First Online: 28 March 2019
Compliance with ethical standards
: The authors declare no competing interests.
: This article does not contain any experiments involving humans or animals that have been performed by any of the authors.