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Ryoo JH, Kim SG, Suh BS, Kim DI, Park SK.Ryoo JH, et al.J Korean Med Sci. 2011 Jun;26(6):753-8. doi: 10.3346/jkms.2011.26.6.753. Epub 2011 May 18.J Korean Med Sci. 2011.PMID: 21655060Free PMC article.
Ryoo JH, Choi JM, Oh CM, Kim MG.Ryoo JH, et al.J Korean Med Sci. 2013 Jun;28(6):855-60. doi: 10.3346/jkms.2013.28.6.855. Epub 2013 Jun 3.J Korean Med Sci. 2013.PMID: 23772149Free PMC article.