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García-Del Portillo F, Pucciarelli MG, Casadesús J.García-Del Portillo F, et al.Proc Natl Acad Sci U S A. 1999 Sep 28;96(20):11578-83. doi: 10.1073/pnas.96.20.11578.Proc Natl Acad Sci U S A. 1999.PMID: 10500219Free PMC article.