Li, Jie
Wang, Jia
Yang, Zhitao
Wang, Hexiang
Che, Junyi
Xu, Wenjian
Article History
Received: 24 May 2018
Accepted: 7 August 2018
First Online: 16 August 2018
Ethics approval and consent to participate
: Ethical approval was obtained by the local institutional review board (Ethical Committee of Affiliated Hospital of Qingdao University).
: Not applicable.
: The authors declare that they have no competing interests.
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