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Thomas DB, Gao DL, Self SG, Allison CJ, Tao Y, Mahloch J, Ray R, Qin Q, Presley R, Porter P.Thomas DB, et al.J Natl Cancer Inst. 1997 Mar 5;89(5):355-65. doi: 10.1093/jnci/89.5.355.J Natl Cancer Inst. 1997.PMID: 9060957Clinical Trial.