Funding for this research was provided by:
JSPS KAKENHI Grant (15K19927)
Text and Data Mining valid from 2018-05-21
Received: 6 December 2017
Accepted: 9 May 2018
First Online: 21 May 2018
Ethics approval and consent to participate
: The protocol has been reviewed and approved by the Ethics Committee of Teikyo University (13-023, 7/11/2013).
: All authors declare that they have no competing interests.
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