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Opal SM, Palardy JE, Marra MN, Fisher CJ Jr, McKelligon BM, Scott RW.Opal SM, et al. Among authors: marra mn.Lancet. 1994 Aug 13;344(8920):429-31. doi: 10.1016/s0140-6736(94)91767-1.Lancet. 1994.PMID: 7520106