Funding for this research was provided by:
Grants-in-Aid from the Ministry of Education, Science, Sports and Culture of Japan (18K06997, 15K08355)
Hidaka Research Projects in the Saitama Medical University (30-D-1-3)
Text and Data Mining valid from 2019-01-24
Received: 19 September 2018
Accepted: 10 January 2019
First Online: 24 January 2019
Ethics approval and consent to participate
: This study was approved by the institutional review board of Saitama Medical University International Medical Center (reference number, 16–257).
: Not applicable.
: The authors declare that they have no competing interests.
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