Received: 30 May 2017
Accepted: 28 August 2017
First Online: 2 September 2017
Ethics approval and consent to participate
: This study is a retrospective review of patient records. The study protocol was approved by Kobe University Graduate School of Medicine Ethics Committee on September 8, 2011 (No 1220), and informed consent for participation in the study was obtained from all participants.
: Not applicable.
: The authors declare that they have no competing interests.
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