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Citation Information: J Clin Invest. 1971;50(5):1000-1004. https://doi.org/10.1172/JCI106569.
Abstract
Placental transport of vitamin B12 was studied in the pregnant rat in two series of experiments. In the first series animals were given cyanocobalamin-57Co intravenously at various stages of gestation. High specific activity tracer was used and doses of B12 were 1-2 ng per animal. The rats were killed from 15 min to 24 hr after injection and the fetuses, placentas, and serum were assayed for radioactivity. In the second series using uninjected animals, absolute amounts of vitamin B12 in fetuses and placentas were measured at stages of gestation from day 12 through day 20.
Authors
Stanley E. Graber, Ursula Scheffel, Barbara Hodkinson, Patricia A. McIntyre
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