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Bertrand D, Galzi JL, Devillers-Thiéry A, Bertrand S, Changeux JP.Bertrand D, et al. Among authors: changeux jp.Proc Natl Acad Sci U S A. 1993 Aug 1;90(15):6971-5. doi: 10.1073/pnas.90.15.6971.Proc Natl Acad Sci U S A. 1993.PMID: 7688468Free PMC article.