Funding for this research was provided by:
JSPS KAKENHI (JP16K20817)
Japan Society for the Promotion of Science (15K16565)
Received: 20 January 2017
Accepted: 3 July 2017
First Online: 6 August 2017
Ethics approval and consent to participate
: This study protocol was approved by the ethics committee of the Shiga University of Medical Science (27–229). Informed consent was obtained by the use of an opt-out methodology based on the low risk to the patient.
: Not applicable.
: The authors declare that they have no competing interests.
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