Received: 23 January 2018
Accepted: 9 April 2018
First Online: 20 June 2018
Ethics approval and consent to participate
: Animal care was conducted in accordance with the guidelines of Chiba University. All animal experiments were approved by the Chiba University Review Board for Animal Care. All patients signed informed consent forms, and the study was approved by Ethics Committee of the Chiba University Graduate School of Medicine and each participating hospital.
: The authors declare that they have no competing interests.
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