Text and Data Mining valid from 2019-04-08
Received: 23 January 2019
Accepted: 1 April 2019
First Online: 8 April 2019
Ethics approval and consent to participate
: The ethics committee of Weihai Municipal Hospital had approved the study.
: Written informed consent was obtained from the patients for publication of this study. Copies of the written consent are available for review by the Editor-in-Chief of this journal.
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