Text and Data Mining valid from 2018-04-05
Received: 14 July 2017
Accepted: 22 February 2018
First Online: 5 April 2018
Ethics approval and consent to participate
: This retrospective study and clinical record reviews were approved by the Institutional Review Board of Kagoshima University (No. 28–101).
: Not applicable.
: The authors declare that they have no competing interests.
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