Funding for this research was provided by:
Keiryokai Collaborative Research Grant (#136)
Grant-in-Aid for Scientific Research KAKENHI (JP17K10646, JP17K10605)
Received: 19 April 2018
Accepted: 22 June 2018
First Online: 2 July 2018
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of Iwate Medical University School of Medicine.
: Not applicable.
: The authors declare that they have no competing interests.
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