Text and Data Mining valid from 2018-07-17
Received: 18 February 2018
Accepted: 6 June 2018
First Online: 17 July 2018
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board of Kobe City Medical Center General Hospital and the Board waived the need for patients’ consent (No. zn170408).
: The authors declare that they have no competing interests.
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