Liu, Liang http://orcid.org/0000-0003-3306-0563
Zuo, Yanhua
Xu, Yan
Zhang, Zongfang
Li, Ying
Pang, Jie
Article History
Received: 28 August 2018
Accepted: 7 December 2018
First Online: 19 April 2019
Ethics approval and consent to participate
: This study was approved by the Ethical Committee of Cangzhou Central Hospital (2016021621) and complied with the guidelines and principles of the Declaration of Helsinki. All participants signed written informed consent.
: All participants signed written informed consent for publication.
: The authors declare that they have no competing interests.
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