Text and Data Mining valid from 2019-04-05
Received: 19 October 2018
Accepted: 12 March 2019
First Online: 5 April 2019
Ethics approval and consent to participate
: The present study was approved by the institutional review board for Clinical Research of the General Clinical Research Center in Tokai University School of Medicine.
: Not applicable.
: The authors declare that they have no competing interests.
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