Received: 13 April 2018
Accepted: 29 June 2018
First Online: 2 October 2018
Ethics approval and consent to participate
: The study design and consent forms of all the procedures performed were approved by the ethics committee for human participants of the Niigata University School of Medicine (Niigata, Japan) in accordance with the Helsinki Declaration of 1964 as revised in 2013. Written informed consents to participate in the study were obtained from all the participants.
: Written informed consents for the publication of these were obtained from all the participants.
: Yutaka Kitamura, Masashi Suzuki, Tsuneyuki Tsukioka, Kazushige Isobe, Tetsuhiro Tsujino, Taisuke Watanabe, Takao Watanabe, Hajime Okudera, Koh Nakata, Takaaki Tanaka, and Tomoyuki Kawase declare that they have no competing interests.
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