villus


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villus

 [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.

vil·lus

, pl.

vil·li

(vil'ŭs, vil'ī), Do not confuse this word with the adjective villous.
1. A projection from the surface, especially of a mucous membrane. If the projection is minute, as from a cell surface, it is termed a microvillus.
2. An elongated dermal papilla projecting into an intraepidermal vesicle or cleft.
[L. shaggy hair (of beasts)]

villus

/vil·lus/ (vil´us) pl. vil´li   [L.] a small vascular process or protrusion, especially from the free surface of a membrane.
arachnoid villi 
1. microscopic projections of the arachnoid into some of the venous sinuses.
chorionic villus  one of the threadlike projections growing in tufts on the external surface of the chorion.
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.
Intestinal villus.
synovial villi  slender projections of the synovial membrane from its free inner surface into the joint cavity.

villus

(vĭl′əs)
n. pl. villi (vĭl′ī)
1. Biology A minute projection arising from a mucous membrane, especially:
a. One of the numerous vascular projections of the small intestine.
b. One of the fingerlike projections of the chorion that contribute to the formation of the placenta in mammals.
2. Botany A fine, hairlike epidermal outgrowth.

villus

[vil′əs] pl. villi
Etymology: L, shaggy, hair
one of the many tiny projections, barely visible to the naked eye, clustered over the entire mucous surface of the small intestine. Villi are covered with epithelium that diffuses and transports fluids and nutrients. They are larger in some parts of the intestine than in others and flatten out when the intestine distends. Each villus has a core of delicate areolar and reticular connective tissue supporting the epithelium, various capillaries, and often a single lymphatic lacteal that fills with milky white chyle during the digestion of a fatty meal. villous, adj.
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Villus

vil·lus

, pl. villi (vil'ŭs, -ī)
1. A projection from the surface, especially of a mucous membrane. If the projection is minute, as from a cell surface, it is termed a microvillus.
2. An elongated dermal papilla projecting into an intraepidermal vesicle or cleft.
See also: festooning
[L. shaggy hair (of beasts)]

villus

(vil'us) plural.villi [L., tuft of hair]
A small fold or projection of some mucous membranes.

arachnoid villus.

Arachnoid granulation.

chorionic villus.

One of the tiny vascular projections of the chorionic surface that become vascular and help to form the placenta.
See: embryo for illus.; chorion
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VILLI OF SMALL INTESTINE

intestinal villus.

One of the multiple, minute projections of the intestinal mucosa into the lumen of the small intestine. These projections increase the surface area for absorption of water and nutrients; each contains a capillary network and a lacteal.
See: illustration

synovial villus.

One of the thin projections of the synovial membrane into the joint cavity.

villus

(pl. villi) a finger-like outgrowth, as in the lining of the SMALL INTESTINE. Villi effectively increase the surface area of the gut wall and contain
  1. (a) blood vessels for absorption of carbohydrates and amino acids which pass into the hepatic portal SYSTEM
  2. (b) lacteals which absorb fats into the LYMPHATIC SYSTEM.

villus

elongated dermal papilla characteristic of verruca formation

vil·lus

, pl. villi (vil'ŭs, -ī) Do not confuse this word with the adjective villous.
1. Projection surface, especially from a mucous membrane.
2. An elongated dermal papilla projecting into an intraepidermal vesicle or cleft.

villus

pl. villi [L.] a small process or protrusion, as from the free surface of a membrane.

arachnoid villus
microscopic projections of the arachnoid into some of the venous sinuses. Called also arachnoid granulations.
chorionic villus
threadlike projections originally occurring uniformly over the external surface of the chorion.
intestinal villus
multitudinous threadlike projections covering the surface of the mucous membrane lining the small intestine, serving as the sites of absorption of fluids and nutrients.
Enlarge picture
Organization of an intestinal villus. By permission from Guyton R, Hall JE, Textbook of Medical Physiology, Saunders, 2000
synovial villus
slender projections from the surface of the synovial membrane into the cavity of a joint; called also haversian glands.
References in periodicals archive ?
There were made two slides per animal and each sampled as equivalent to ten intestinal villi to evaluate high (AV) and wide villus (LV) (Jin, Reynolds, Redmer, Caton, & Crenshaw, 1994; Junqueira & Carneiro, 1995), by electron microscopy and an image analyzing system.
Outcome of 1,355 consecutive transabdominal chorionic villus samplings in 1,351 patients].
Considering the regression analysis, all variables of intestinal morphology worsened as SC levels increased; the villus height and villusxrypt ratio in the duodenum, jejunum and ileum linearly reduced (p = 0.
The measurements of villus height (from the tip of villus to the villus-crypt junction), villus width, crypt depth, villus height: crypt depth ratio and thickness of muscle layer were made.
2) was unexpected, based on the biochemical results of the cultured chorionic villus specimen.
Chorionic villus sampling can be done in the 10th week of pregnancy, but a bad result often means a first-trimester abortion.
Current invasive prenatal diagnostics such as amniocentesis and chorionic villus sampling (CVS) can definitively detect chromosomal abnormalities, but these procedures are costly and risky.
In each slice, the height of villi (determined as the distance from the villus tip to the crypt mouth) and the associated depth of crypts (measured from the crypt mouth to the base) were measured through computer-aided light microscope (Nikon, Tokyo, Japan).
Invasive testing by chorionic villus sampling or amniocentesis should be performed to confirm a normal karyotype, thereby excluding partial molar pregnancy.
As with PR, the focal hypervascularity is an adaptive mechanism, reaching the level of chorangiosis in some cases, whereas, in other cases, the villous capillary profiles remain between 7 and 9 per chorionic villus (incipient or emerging chorangiosis).