Funding for this research was provided by:
Japan Society for the Promotion of Science (18K10002)
Received: 18 December 2018
Accepted: 27 February 2019
First Online: 20 March 2019
Ethics approval and consent to participate
: Informed consent was obtained from all participants. This study was approved by the ethics committee of Okayama Medical School (No. 1602–039).
: Consent for publication was obtained from all participants.
: The authors declare that they have no competing interests.
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