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Related to Capillaries: Peritubular capillaries


(kap′ĭ-ler″ē) plural.capillaries [L. capillaris, hairlike]
1. Any of the minute blood vessels, averaging 0.008 mm in diameter, that connect the ends of the smallest arteries (arterioles) with the beginnings of the smallest veins (venules).
2. Pert. to a hair; hairlike.

arterial capillary

One of the very small vessels that are the terminal branches of the arterioles or metarterioles.

bile capillary

One of the intercellular biliary passageways that convey bile from liver cells to the interlobular bile ducts. Also called bile canaliculus.

blood capillary

One of the minute blood vessels that convey blood from the arterioles to the venules and form an anastomosing network that brings the blood into intimate relationship with the tissue cells. Its wall consists of a single layer of squamous cells (endothelium) through which oxygen diffuses to the tissue and products of metabolic activity enter the bloodstream. Blood capillaries average about 8 μm in diameter.
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lymphatic capillary

A thin-walled lymphatic vessel at the beginning of a branch of the lymphatic system. Lymphatic capillaries have closed ends, but have no basement membranes and are more permeable than blood capillaries. Fluids, salts, proteins, large molecules, particles, debris, microorganisms, and migrating cells can pass from the interstitial spaces into lymphatic capillaries. Lymphatic capillaries lead to larger lymphatics that transport the lymph to lymph nodes. See: illustration

secretory capillary

Any of the very small canaliculi that are part of the secretory outflow path receiving secretion discharged from gland cells.

venous capillary

One of the minute vessels that convey blood from a capillary network into the small veins (venules).
Medical Dictionary, © 2009 Farlex and Partners


The smallest arteries which, in the lung, are located next to the alveoli so that they can pick up oxygen from inhaled air.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Caption: FIGURE 5: Fluorescein angiography image in the left eye at (a) initial visit demonstrating loss of small capillaries, but nonperfusion areas were not observed.
Typically, PVOD shows dilated capillaries without proliferation, as well as small veins blocked by organizing thrombi rather than infiltrating capillaries.
The mature intermediate villi contain supplying arterioles, thin capillaries and venules.
For longer capillaries, higher numbers of elements, as many as 35 000 elements, were employed.
Particles were localized within epithelial and endothelial cells, within fibroblasts and between collagen fibrils in the connective tissue, within blood capillaries, and even within RBCs (Figure 1).
The geometric shapes used included 50-[micro]m diameter posts, 100-[micro]m notches, and connecting capillaries with 10- to 200-[micro]m cross-sectional diameters (Fig.
These capillaries actually "leak" blood that begins to oxidize (through a process called hemoglobin degradation) ...
The new version has several enhancements, including the ability to measure capillary wear and incorporate it in pass/fail criteria, the ability to measure angled capillaries and to inspect spinnerettes that may have damage-preventive coatings.
(1) They usually originate in the capillaries, but they sometimes arise in the venous vessels, as well.