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Chiu K, Lau WM, Lau HT, So KF, Chang RC.Chiu K, et al.J Vis Exp. 2007;(7):269. doi: 10.3791/269. Epub 2007 Aug 30.J Vis Exp. 2007.PMID: 18989440Free PMC article.
Chiu K, Lau WM, Yeung SC, Chang RC, So KF.Chiu K, et al.J Vis Exp. 2008 Jun 17;(16):819. doi: 10.3791/819.J Vis Exp. 2008.PMID: 19066544Free PMC article.