Funding for this research was provided by:
Scientific Research from Japan Society (15K19305)
Received: 16 March 2017
Accepted: 18 January 2018
First Online: 31 January 2018
Ethics approval and consent to participate
: This retrospective study was conducted in accordance with the standards of the Declaration of Helsinki and was approved by the Medical Ethics Committee of Asahikawa Medical University. (Number: 1303). All patients have provided written informed consent for their information to be stored and used in the hospital database.
: Not applicable.
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