Funding for this research was provided by:
Japan Society for the Promotion of Science (JP15K08107, JP26860265)
Received: 4 September 2017
Accepted: 7 November 2017
First Online: 8 January 2018
Ethics approval and consent to participate
: Ethical approval for this study was granted by the institutional review board of the Juntendo University Urayasu Hospital. Written informed consent was obtained from all the patients according to the Declaration of Helsinki.
: Not applicable.
: The authors declare that they have no competing interests.
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