Funding for this research was provided by:
Grant-in-Aid for Scientific Research from the Ministry of Health, Labour and Welfare, Japan
Received: 13 January 2016
Accepted: 30 January 2018
First Online: 8 February 2018
Ethics approval and consent to participate
: The study was approved by the ethical review board of National Cerebral and Cardiovascular Center in Japan. In accordance with the ethical review’s decision, informed consent was not obtained from the subjects.
: Not applicable.
: The authors declare that they have no competing interests.
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