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Parr N, Mackie CR, Baxter JN, Jenkins SA, Ellenbogen S.Parr N, et al. Among authors: mackie cr.Br Med J (Clin Res Ed). 1985 Aug 31;291(6495):603. doi: 10.1136/bmj.291.6495.603-a.Br Med J (Clin Res Ed). 1985.PMID: 3929889Free PMC article.No abstract available.