Text and Data Mining valid from 2018-10-01
Received: 2 July 2018
Accepted: 21 September 2018
First Online: 1 October 2018
Ethics approval and consent to participate
: The institutional review board of our hospital approved this retrospective study (100-4178B).Consent to participate was not applicable.
: Not applicable
: The authors declare that they have no competing interests.
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