Funding for this research was provided by:
A grant from Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education (NRF-2015R1D1A1A02061859)
A grant from Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Science, ICT & Future Planning (NRF-2012R1A1A1013260)
A Korea University Grant
Text and Data Mining valid from 2018-05-30
Received: 9 August 2017
Accepted: 9 May 2018
First Online: 30 May 2018
Ethics approval and consent to participate
: The study protocol was approved both by the Research Committee and the Ethics in Research Committee of in Korea University Medical Center. Written informed consent was obtained. All procedures were conducted based on the Declaration of Helsinki and local regulations.
: The authors declare that they have no competing interests.
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