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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 ?
The rounded nuclei, increased cytoplasmic volume, and distinct cell membranes may contribute to a "monotonous" look in some acini (Figure 12).
Ducts and acini are lined with flattened epithelium which lack true papillae.
Here, we demonstrated that SFN decreased production of inflammatory mediators including TNF-[alpha], IL-1[beta], and IL-6 and inhibited NF-[kappa]B activation in cerulein-treatment acini or mice.
There are several possible explanations for the decrease in the volume density of exocrine pancreatic acini in the treated group.
This measured square was used for counting the number of intercalated ducts, striated ducts, acini and demilunes.
Acini and ducts of the mammary gland were lined with large cuboidal epithelium cells.
As women age, especially as they approach menopause, the risk of breast cancer declines because the lobules and acini disappear.
The histological observations of the entire set of individuals and gonad levels revealed that the distribution of ferritin in the sampled tissues could be divided into 5 sequential steps: (1) uptake into intestinal epithelium, (2) appearance in hemocytes among the connective tissue surrounding the intestine, (3) appearance in hemocytes at the exterior faces of acini, (4) appearance in hemocytes within the acini, and (5) appearance in hemocytes/follicle cells appressed to oocytes.
Prostatic acini convert from a nondilated to a dilated form around the time of puberty and could therefore be used as a marker of sexual maturity.
Fairly vascularized pancreatic acini were observed around the pyloric caeca and in the initial portion of S1 (Fig.