air sac


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Related to air sac: bronchiole

al·ve·o·lar sac

1. terminal dilation of the alveolar ducts, which give rise to alveoli in the lung; a small air chamber in the pulmonary tissue from which the pulmonary alveoli project like bays and into which an alveolar duct opens; Synonym(s): sacculus alveolaris [TA]
2. in birds, air-containing extensions of bronchi that connect with bone cavities.
Synonym(s): air sac

air sac

n.
1. An air-filled space in the body of a bird that forms a connection between the lungs and bone cavities and aids in breathing and temperature regulation.
2. See alveolus.
3. A saclike, thin-walled enlargement in the trachea of an insect.
4. An inflatable pouch attached to the larynx in certain mammals, including the nonhuman great apes.
Air sacclick for a larger image
Fig. 18 Air sac . The air-sac system of a bird (left-side).

air sac

a thin-walled extension to the lungs, present in the thorax, abdomen and bones of birds. Air sacs also occur as diverticula (outgrowths) of the TRACHEA in insects, where, as in birds, they are important in respiration.
References in periodicals archive ?
The abdominal air sac (A) thickened by friable tan to grey exudate.
([dagger]) Three juvenile chickens and turkeys inoculated through the air sac were killed on days 0, 2, 4, 6, 8, and 14 posinoculation, and left and right lung lobes were removed for analysis by real-time reverse transcription-PCR.
Molecular characterization: Polymerase chain reaction (PCR) was used for detection of MG in organs (trachea, lungs and air sacs) of infected birds as described by Santha et al.
(17,18) The intestinal peritoneal cavity contains the urogenital organs, gastrointestinal tract, spleen, and left and right abdominal air sacs. (17,18) The only connection between the different coelomic cavities occurs between the intestinal peritoneal cavity and the left dorsal hepatic cavity.
Some of the models contained an air sac, the Daily Mail reported.
The lung-on-a-chip microdevice takes a new approach to tissue engineering by placing two layers of living tissues-the lining of the lung's air sacs and the blood vessels that surround them-across a porous, flexible boundary.
The right and left testes were enlarged, approximately 3 X 2.5 X 1.5 cm, and soft with multifocal tan ridges compressing the tunica albuginea and associated abdominal air sacs. On cut sections, the testicular parenchyma moderately bulged and occasional irregular soft necrotic areas were present within the parenchyma (Fig 2A).
Tracheal endoscopy revealed an obstruction of approximately 90% of the tracheal lumen, in addition to mild suspected aspergillosis of the air sacs. Tracheal resection and anastomosis were performed, during which 1.5 cm of abnormal trachea was removed.
Marek's disease, or leucosis, may result in gonadal neoplasia, especially in chickens, leading to massive enlargement of the reproductive organs and subsequent air sac compression.
A total of 20-30 nematodes, approximately 20-30 cm in length, were found in the coelomic cavity and in the thoracic and abdominal air sacs, which were diffusely opaque and thickened.
Additionally, administration of amphotericin B, as a nebulization agent, often is recommended, especially for cases with significant air sac disease.