acinus


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Related to acinus: surfactant, emphysema, liver acinus, Acinar gland

acinus

 [as´ĭ-nus] (pl. a´cini) (L.)
any of the smallest lobules of a compound gland.
liver acinus the smallest functional unit of the liver, a mass of liver parenchyma that is supplied by terminal branches of the portal vein and hepatic artery and drained by a terminal branch of the bile duct.
 Liver acinus: Hepatic lobules are represented by hexagons (solid lines); liver acinus is represented by rhombus (dotted line). From Dorland's, 2000.
pulmonary acinus terminal respiratory unit.

ac·i·nus

, gen. and pl.

ac·i·ni

(as'i-nŭs, -nī), [MIM*604562]
One of the minute grape-shaped secretory portions of an acinous gland. Some authorities use the terms acinus and alveolus interchangeably, whereas others differentiate them by the constricted openings of the acinus into the excretory duct.
[L. berry, grape]

acinus

/ac·i·nus/ (as´ĭ-nus) pl. a´cini   [L.] a small saclike dilatation, particularly one in a gland; see also alveolus.
liver acinus  the smallest functional unit of the liver, a mass of liver parenchyma that is supplied by terminal branches of the portal vein and hepatic artery and drained by a terminal branch of the bile duct.
Enlarge picture
Liver acinus: hepatic lobules are represented by hexagons (solid lines); liver acinus is represented by rhombus (dotted line).
pancreatic acinus  one of the secretory units of the exocrine pancreas, where pancreatic juice is produced.
pulmonary acinus  terminal respiratory unit.
thyroid acini  see under follicle.

acinus

(ăs′ə-nəs)
n. pl. aci·ni (-nī′)
One of the small saclike dilations composing a compound gland.

a·cin′ic (ə-sĭn′ĭk), ac′i·nous adj.

acinus

[as′inəs] pl. acini
Etymology: L, grape
1 any small saclike structure, particularly one found in a gland.
2 See alveolus.

acinus

A small, sac-like out-pouching of a compound gland, as in the breast, pancreas, salivary glands and thyroid.

Lung
A sub-segmental lung structure which, with the primary pulmonary lobule, is the smallest unit of lung tissue. It consists of a terminal bronchiole and the lung parenchyma that arises from it.

Acinus

A subsegmental lung structure which, with the primary pulmonary lobule, is the smallest unit of lung tissue. It consists of a terminal bronchiole and the lung parenchyma that arises from it

ac·i·nus

, pl. acini (as'i-nŭs, -nī) [TA]
One of the minute grape-shaped secretory portions of an acinous gland. Some authorities use the terms acinus and alveolus interchangeably, whereas others differentiate them by the constricted openings of the acinus into the excretory duct.
[L. berry, grape]

acinus

1. The part of the air passage of the lung beyond each of the smallest (terminal) bronchioles. There are about 12,000 acini in each lung. The lung ALVEOLI arise from the acini.
2. Any terminal sac-like process of a compound gland.

acinus

the terminal sac of an alveolar gland. The gland has a multicellular structure with sac-shaped secreting units. In the pancreas, acinar cells secrete the PANCREATIC JUICE.

ac·i·nus

, pl. acini (as'i-nŭs, -nī) [TA] [MIM*604562]
One of the minute grape-shaped secretory portions of an acinous gland.
[L. berry, grape]

acinus ( acini) (as´inəs),

n 1. a saclike cavity present in a gland or the lungs.
2. a group of secretory cells of the salivary gland.
acinus, serous
n a group of serous cells producing serous secretory product such as in the salivary glands.

acinus

pl. acini [L.] any of the smallest lobules of a compound gland.

liver acinus
the smallest functional unit of the liver made up of two wedge-shaped masses of liver parenchyma that are supplied by two neighboring branches of the portal vein and hepatic artery and drained by two central veins and by terminal branches of the bile duct.
References in periodicals archive ?
Ultrafiltration (an extracellular mechanism), a third means of transportation of molecules from blood stream into saliva, is filtration through the spaces between acinus and ductal cells (Fig.
Some are attached to the trabeculae but most oocytes are free in the center of the acinus (Fig.
The final generation of membranous bronchiole is termed terminal bronchiole and opens into a functional unit of the lung termed an acinus, which is composed of respiratory bronchioles, alveolar ducts, and alveoli.
The functional unit of the lung, the acinus, is composed of the terminal bronchiole and the air spaces it supplies (12).
Prahalada et al (24) reported that chronic administration of finasteride resulted in a decrease in the weight of the rat prostate compared with controls, and this finding correlated with a decrease in the total number of epithelial and stromal cells per acinus throughout the treated rat prostate, although they found no qualitative differences in prostatic morphology between the control and finasteride-treated groups.
Furthermore, this region is the point of entry and exit to the ventilatory unit; gases and airborne particles entering and leaving the acinus have to pass through this constricted zone.
The crystalloids were invariably moderate to numerous (92%), averaging 6 to 7 crystalloids within a lumen and at times forming large clusters filling the entire acinus (Figures 1 and 2).
Acinar dropout was assigned a score of 0 when back-to-back glands occurred with no more than the height of a ductal cell thickness between each acinus.