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The small terminal sac of an acinous gland, lined with secreting cells.
An individual drupelet of a multiple fruit.



(1) A structural and functional unit or the terminal secretory portion of the salivary, pancreatic, lacteal, sebaceous, or other saccular (alveolar) glands. The acinus is a bubble-like formation of one or more types of gland cells situated on a basement membrane and surrounded by connective tissue, capillaries, and nerve fibers. The apexes of the cells with their microvilli are directed toward the chamber of the acinus into which the secretion is discharged.

(2) A part of the respiratory apparatus in mammals that includes a section of the lung corresponding to the branches of the terminal bronchus—that is, the bronchioles, alveolar passages, and alveoli. One pulmonary lobule consists of 12–18 acini.

References in periodicals archive ?
In most females from Chiku and Hsiangshan, both the growing oocytes attached to the acinus wall and the free-laying oocytes underwent degeneration and lysis in almost all gonadal acini.
A serum molecule reaching saliva by diffusion must cross 5 barriers: the capillary wall; the interstitial space; the basal cell membrane of the acinus cell or duct cell; the cytoplasm of the acinus or duct cell; and the luminal cell membrane (32).
3] exposure leads to an increased number of Clara cells in the central acinus, which can produce both PG[E.
The number of eggs found in each ovarian tubule (acinus), the number of mature egg number per acinus, and egg size were highest for females at this temperature, indicating increased fecundity and gametogenic maturity.
The terminal respiratory unit of the lung from the respiratory bronchiole to the alveolus is called the acinus.
Mercer has used serial section reconstruction to make the first precise measurements of some of the lung's tiniest structures, such as an acinus - a cluster of alveoli vented by a single airway.
In view of these observations, the centrilobular distribution of 6-MP-mediated injury we observed may be due to the spatial compartmentalization of xenobiotic metabolism within the liver acinus.
The ratio of acinus area occupied by parietal and mature gametes to the area encompassing nutritive phagocytic cells decreased with increasing dietary copper in females and was significantly lower in the l14-mg Cu/kg diet (0.