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Cheng CW, Su JL, Lin CW, Su CW, Shih CH, Yang SF, Chien MH.Cheng CW, et al.PLoS One. 2013;8(2):e56130. doi: 10.1371/journal.pone.0056130. Epub 2013 Feb 14.PLoS One. 2013.PMID: 23457512Free PMC article.