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Annotations Fetoplacental circulation in health and disease 'The first time [in the year 1 743] that I injected the vein of the naval string [cord] while the placenta adhered to the uterus, in separating these two parts it was evident that the injection had nowhere passed further than the placenta. ... From all these experiments and observations, which have been often repeated
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Kingdom et al. (1994) studied this question.
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