ductus venosus

ductus /duc·tus/ (duk´tus) pl. duc´tus   [L.] duct.

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ductus arterio´sus  a fetal blood vessel that joins the descending aorta and left pulmonary artery.

ductus chole´dochus  common bile duct.

ductus de´ferens  the excretory duct of the testis which joins the excretory duct of the seminal vesicle to form the ejaculatory duct.

patent ductus arteriosus  (PDA) abnormal persistence of an open lumen in the ductus arteriosus after birth, flow being from the aorta to the pulmonary artery and thus recirculating arterial blood through the lungs.

ductus veno´sus  a major blood channel that develops through the embryonic liver from the left umbilical vein to the inferior vena cava.

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ductus ve·no·sus (v-nss)

n.

A fetal vein that passes through the liver to the inferior vena cava.

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ductus venosus,

the vascular channel in the fetus passing through the liver and joining the umbilical vein with the inferior vena cava. Before birth it carries highly oxygenated blood from the placenta to the fetal circulation. It closes shortly after birth as pulmonary circulation is established and as the vessels in the umbilical cord collapse and become occluded. See also ductus arteriosus, foramen ovale.

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ductus

pl. ductus [L.] duct.

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ductus arteriosus

a fetal blood vessel that joins the aorta and pulmonary artery. Abnormal persistence of an open lumen after birth results in a patent ductus arteriosus. Called also persistent or patent ductus arteriosus.

ductus choledochus

see bile duct.

ductus deferens

the excretory duct of the testis, which in horses and ruminants joins the excretory duct of the seminal vesicle to form the ejaculatory duct; called also vas deferens.

ductus epididymis

the duct which, in combination with connective tissue and muscle, forms the head, body and tail of the epididymis and continues as the ductus deferens.

ductus epoophori longitudinales

see gartner's ducts.

ductus reuniens

the joining channel between the cochlea and sacculus of the membranous labyrinth of the inner ear.

ductus venosus

a major blood channel that develops through the embryonic liver from the left umbilical vein to the caudal vena cava and closes within a few days after birth. If it remains patent, a congenital portacaval anastamosis is created.