Received: 24 November 2017
Accepted: 18 January 2018
First Online: 30 January 2018
Ethics approval and consent to participate
: The study protocol was conducted according to the guidelines contained within the Declaration of Helsinki and was approved by the institutional review board of Tokushima University Hospital (Approval number H-26). Written informed consent was obtained from all participants before entry into the study.
: Not applicable.
: The authors declare that they have no competing interests.
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