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Chiang JJ, Eisenberger NI, Seeman TE, Taylor SE.Chiang JJ, et al. Among authors: seeman te.Proc Natl Acad Sci U S A. 2012 Feb 7;109(6):1878-82. doi: 10.1073/pnas.1120972109. Epub 2012 Jan 23.Proc Natl Acad Sci U S A. 2012.PMID: 22308464Free PMC article.