Funding for this research was provided by:
the National Natural Science Foundation of China (21605127)
Doctorial Starting Fund of Xinxiang Medical University
Key Research Projects of Henan Higher Education Institutions (19A416007)
Xinxiang Innovative Technology Team (CXTD17004)
Article History
Received: 13 November 2018
Accepted: 13 February 2019
First Online: 22 February 2019
Compliance with ethical standards
: The author(s) declare that they have no competing interests.