Text and Data Mining valid from 2018-11-26
Received: 23 August 2018
Accepted: 15 November 2018
First Online: 26 November 2018
Ethics approval and consent to participate
: This study was approved by the Hospital Ethics Committee of the Wenzhou People’s Hospital. As a retrospective study, written consents were not required.
: The authors declare that they have no competing interests.
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