Funding for this research was provided by:
Japan Society for the Promotion of Science (15K08339)
Received: 14 January 2018
Accepted: 11 May 2018
First Online: 25 May 2018
Ethics approval and consent to participate
: The study protocol was approved by the Gunma University school of medicine ethical review board for medical research involving human subjects (Permit Number: 150044). Written informed consent for the collection of specimens and the use of specimens for this study was obtained from all participating patients.
: The authors declare that they have no competing interests.
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