Received: 25 May 2017
Accepted: 25 January 2018
First Online: 30 January 2018
Ethics approval and consent to participate
: This study was designed in accordance with the Declaration of Helsinki and was approved by the Institutional Review Board of Kyoto Prefectural University of Medicine. All patients received sufficient explanation of the study, and written informed consent was obtained.
: Not applicable.
: The authors declare that they have no competing interests.
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