Text and Data Mining valid from 2018-07-04
Received: 23 October 2017
Accepted: 27 June 2018
First Online: 4 July 2018
Ethics approval and consent to participate
: The study was approved by the Tongji Hospital Ethics Committee. The Ethics Committee does not require written or verbal informed consent for retrospective studies and was, thus, not sought after.
: Not applicable.
: The authors declare that they have no competing interests.
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