Funding for this research was provided by:
Tohoku Bureau of Economy (Tohoku 1607028)
Received: 9 December 2018
Accepted: 19 February 2019
First Online: 25 February 2019
Ethics approval and consent to participate
: Written informed consent was obtained from all patients or their families. The study was approved by the Nara Medical University institutional review board (Approval number, 2012–541), and the study was conducted in accordance with the ethical standards of the Declaration of Helsinki.
: Not applicable.
: The authors declare that they have no competing interests.
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