Text and Data Mining valid from 2018-09-19
Received: 2 July 2018
Accepted: 12 September 2018
First Online: 19 September 2018
Ethics approval and consent to participate
: Ethical approval for the study was obtained from the institutional review board of Yokohama City University Hospital (B140904023). Informed and written consent was obtained from all patients.
: Not applicable.
: The authors declare that they have no competing interests.
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