chorionic villi

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Related to chorionic villi: hydatidiform mole


pertaining to the chorion.
chorionic villi numerous branching projections from the external surface of the chorion that provide for exchange between the maternal and fetal circulation. Oxygen and nutrients in the maternal blood diffuse through the walls of the villi and enter the blood of the embryo or fetus. Carbon dioxide and waste products diffuse from blood in the fetal capillaries through the walls of the villi into the maternal blood. See also chorionic villus sampling.


 [vil´us] (L.)
a small vascular process or protrusion, as from the free surface of a membrane.
arachnoid villi microscopic projections of the arachnoid into some of the venous sinuses.
chorionic villi see chorionic villi.
intestinal villi multitudinous threadlike projections covering the surface of the mucous membrane lining the small intestine, serving as the sites of absorption of fluids and nutrients.
synovial villi slender projections from the surface of the synovial membrane into the cavity of a joint; called also haversian glands.

cho·ri·on·ic vil·li

vascular processes of the chorion of the embryo entering into the formation of the placenta.

cho·ri·on·ic vil·li

(kōr'ē-on'ik vil'ī)
Vascular processes of the chorion of the embryo entering into the formation of the placenta.

chorionic villi

The finger-like projections from the CHORION into the wall of the womb at the site at which the PLACENTA is developing. Since both the chorionic villi and the embryo are derived from the same fertilized ovum a sample of the former provides material for genetic studies of the latter. Chorionic villus sampling has become an important method of early pre-natal screening for genetic defects.

Chorionic villi

Microscopic, finger-like projections that emerge from the outer sac which surrounds the developing baby. Chorionic villi are of fetal origin and eventually form the placenta.
References in periodicals archive ?
Intermediate mature and immature chorionic villi constitute 40-45% of the placental area.
If TVS yields a non-diagnostic result with no direct evidence of a NIP or EP, histology of endometrial curetting showing chorionic villi will exclude an EP.
The most important point about chorionic villi sampling or amniocentesis is the risk of Rh sensitization that it take that mother's Rh- and embryo's Rh+.
The chorionic villi extracted were sent for DNA analysis to be done by the Department of Pathology at PNS Shifa Hospital Karachi for screening of Beta-thalassemia mutations by ARMS (Amplification Refractory Mutation System), which is based on polymerase reaction for common mutations.
This allows the chorionic villi of the placenta to directly attach to the myometrium.
In the late 1980s and early 1990s, there was just a hint of concern in the medical and scientific communities about the safety of chorionic villi sampling.
It was obvious that the enlargement of the villi was due not only to edema, but also to Hofbauer cell hyperplasia, which had also significantly contributed to the greater-than-expected size of the chorionic villi.
The oxygenated blood returns to the foetus via the venules and veins in the chorionic villi that join to form the umbilical vein.
Objectives: To determine the effectiveness and feasibility of transabdominal chorionic villi sample (CVS) procedure for prenatal diagnosis of b-thalassaemia in a Muslim majority community.
In fact, even among patients who reported their highest level of education as college or graduate school, 64% said they were not sure what level of risk would make them consider a diagnostic test such as amniocentesis or chorionic villi sampling, Dr.
The technique of cariometry was utilized for evaluation of nuclear parameters of cells in deciduous and spongy layers, and of chorionic villi in the rat placenta.
This policy was adopted after we had another patient with complex I deficiency in whom the native chorionic villi had normal activities, whereas the cultured ones were clearly complex I-deficient.