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Ko WF, Helzlsouer KJ, Comstock GW.Ko WF, et al. Among authors: comstock gw.J Natl Cancer Inst. 1994 Dec 21;86(24):1874-5. doi: 10.1093/jnci/86.24.1874.J Natl Cancer Inst. 1994.PMID: 7990163No abstract available.