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Nielsen JB, Ikkala E, Sölvell L, Björn-Rasmussen E, Ekenved G.Nielsen JB, et al.Acta Med Scand. 1973 Jul-Aug;1-2(1):123-7. doi: 10.1111/j.0954-6820.1973.tb19416.x.Acta Med Scand. 1973.PMID: 4727245Clinical Trial.No abstract available.