Funding for this research was provided by:
Japan Society for the Promotion of Science (16H05170)
Received: 14 December 2018
Accepted: 18 January 2019
First Online: 28 January 2019
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board of Fukui University Hospital.
: Not applicable.
: The authors declare that they have no competing interests.
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