Funding for this research was provided by:
National Natural Science Foundation of China (81560480)
Health Science Research Program of Gansu Province (GSWSKY2016-19)
Ph.D. Science Research Foundation of Lanzhou University Second Hospital
Article History
Received: 24 September 2018
Accepted: 30 March 2019
First Online: 8 May 2019
Compliance with ethical standards
:
: All authors declare that there was no any conflict of interests in this article.
: None.
: This study is a meta-analysis of other studies where all procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2008.