Wang, Lei
Yang, Shujian
Yang, Shan
Zhao, Cheng
Tian, Guangye
Gao, Yuxiu
Chen, Yongjian
Lu, Yun
Article History
Received: 27 September 2018
Accepted: 2 January 2019
First Online: 8 January 2019
Ethics approval and consent to participate
: The present study was approved by the Ethics Committee of the Affiliated Hospital of Qingdao University. Since the present study was a post hoc analysis of exist data, there was no informed consent.
: No consent is required.
: The authors declare that they have no competing interests.
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