Funding for this research was provided by:
National Research Foundation of Korea (2015R1A2A2A01006779)
Received: 9 March 2017
Accepted: 29 January 2018
First Online: 7 February 2018
Ethics approval and consent to participate
: This study was approved by the Institutional Review (approval number, KUH1160098) granted by Institutional Review Board of Konkuk University Medical Center, Seoul, Korea; Chairperson Prof SH. Lee. Written informed consent was obtained from all patients.
: Not applicable.
: The authors declare that they have no competing interests.
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