Kunigo, Tatsuya
Murouchi, Takeshi
Yamamoto, Shuji
Yamakage, Michiaki
Article History
Received: 30 November 2017
Accepted: 10 January 2018
First Online: 22 January 2018
Ethics approval and consent to participate
: This study protocols were approved by the institutional ethics committee of Sapporo Medical University School of Medicine.
: The authors declare that they have no competing interests.
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