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Johnson N, Fletcher O, Naceur-Lombardelli C, dos Santos Silva I, Ashworth A, Peto J.Johnson N, et al. Among authors: ashworth a.Lancet. 2005 Oct 29-Nov 4;366(9496):1554-7. doi: 10.1016/S0140-6736(05)67627-1.Lancet. 2005.PMID: 16257342Review.