Funding for this research was provided by:
Saitama Medical University (26-B-1-24)
Text and Data Mining valid from 2018-05-18
Received: 18 January 2018
Accepted: 10 May 2018
First Online: 18 May 2018
Ethics approval and consent to participate
: The study was approved by the Saitama Medical Center institutional review board (approval number 700).
: The authors declare that they have no competing interests.
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