Funding for this research was provided by:
Received: 29 September 2017
Accepted: 23 April 2018
First Online: 2 May 2018
Ethics approval and consent to participate
: This study was conducted in accordance with the Helsinki Declaration and was approved by the institutional ethical review board of Dokkyo Medical University Hospital. Each patient signed a consent form that was approved by our institutional Committee on Human Rights in Research. All samples were anonymized before analysis was performed, to guarantee the protection of privacy.
: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.
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