Funding for this research was provided by:
Japan Society for the Promotion of Science (JP16H06267)
Received: 26 November 2018
Accepted: 1 February 2019
First Online: 11 February 2019
Ethics approval and consent to participate
: Institutional ethics review board at Niigata University approved this study. The patient gave written informed consent.
: Written informed consent was obtained from the patient.
: The authors declare that they have no competing interests.
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