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Hebert JR, Hurley TG, Olendzki BC, Teas J, Ma Y, Hampl JS.Hebert JR, et al.J Natl Cancer Inst. 1998 Nov 4;90(21):1637-47. doi: 10.1093/jnci/90.21.1637.J Natl Cancer Inst. 1998.PMID: 9811313