Funding for this research was provided by:
Japan Society for the Promotion of Science (24791362)
Received: 29 October 2018
Accepted: 2 January 2019
First Online: 16 January 2019
: Not applicable.
: Ethical approval: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. This prospective study was approved by the local institutional review board of our hospital, and written informed consent was obtained from all patients before enrollment.
: Informed consent was obtained from all individual participants included in the study.
: The authors declare that they have no competing interests.
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