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Wu TC, Guarnieri FG, Staveley-O'Carroll KF, Viscidi RP, Levitsky HI, Hedrick L, Cho KR, August JT, Pardoll DM.Wu TC, et al.Proc Natl Acad Sci U S A. 1995 Dec 5;92(25):11671-5. doi: 10.1073/pnas.92.25.11671.Proc Natl Acad Sci U S A. 1995.PMID: 8524826Free PMC article.