Fan, Fang
Jia, Zhiyang
Li, Kejun
Zhao, Xiaobin
Ma, Qingmin
Funding for this research was provided by:
Hebei provincial health and Family Planning Commission (ZL20140018)
Article History
Received: 22 March 2017
Accepted: 8 June 2018
First Online: 28 June 2018
Ethics approval and consent to participate
: This study was approved by the medical ethics committee of the Hebei general hospital, and the reference number was “NO.201613”. Informed consent was obtained from all participants in a written from.
: Written informed consent for publication was obtained from all patients.
: The authors declare they have no competing interests.
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