Zhang, Jinhong
Wang, Hong
Yang, Shuying
Wang, Xiufen
Article History
Received: 7 December 2017
Accepted: 24 January 2018
First Online: 2 February 2018
Ethics approval and consent to participate
: This study was approved by the ethics committee of Cangzhou People’s Hospital.
: All participants have given consent for publication.
: The authors declare that they have no competing interests.
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