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Roh MI, Kim JH, Byeon SH, Koh HJ, Lee SC, Kwon OW.Roh MI, et al.Yonsei Med J. 2008 Dec 31;49(6):931-41. doi: 10.3349/ymj.2008.49.6.931.Yonsei Med J. 2008.PMID: 19108016Free PMC article.