Geng, Yunhang
Gai, Pengzhou
Article History
Received: 14 November 2017
Accepted: 10 December 2018
First Online: 22 December 2018
Ethics approval and consent to participate
: The research was reviewed and written approved by the Ethic Committee of the Qindao University Medical College Affiliated Yantai Yuhuangding Hospital. And written informed consent was obtained from all study participants.
: Not applicable.
: The authors declare no competing interests.
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