Duan, Yuxiang
Wang, Anxin
Wang, Yan
Wang, Xizhu
Chen, Shuohua
Zhao, Quanhui
Li, Xiuling
Wu, Shouling http://orcid.org/0000-0001-7095-6022
Yang, Li
Article History
Received: 9 February 2019
Revised: 29 April 2019
Accepted: 3 May 2019
First Online: 22 May 2019
Compliance with ethical standards
:
: On behalf of all authors, the corresponding author states that there is no conflict of interest.
: This study followed the ethical standards of the Declaration of Helsinki and was approved by the Ethics Committee of Kailuan General Hospital.