Text and Data Mining valid from 2018-04-04
Received: 10 January 2018
Accepted: 28 March 2018
First Online: 4 April 2018
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of the University of Occupational and Environmental Health, Japan (H26–003). A written informed consent was obtained from the patient.
: The authors declare that they have no competing interests.
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