Shibutani, Masatsune
Maeda, Kiyoshi
Nagahara, Hisashi
Fukuoka, Tatsunari
Matsutani, Shinji
Kimura, Kenjiro
Amano, Ryosuke
Hirakawa, Kosei
Ohira, Masaichi
Article History
Received: 26 September 2017
Accepted: 13 March 2019
First Online: 18 March 2019
Ethics approval and consent to participate
: This research conformed to the provisions of the Declaration of Helsinki. Written informed consent was obtained from all participants. This retrospective study was approved by our institutional review board (approval No.926).
: Not applicable.
: The authors declare that they have no competing interests.
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