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Stepanov I, Villalta PW, Knezevich A, Jensen J, Hatsukami D, Hecht SS.Stepanov I, et al.Chem Res Toxicol. 2010 Jan;23(1):66-73. doi: 10.1021/tx900281u.Chem Res Toxicol. 2010.PMID: 19860436Free PMC article.