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(brŏng′kē-ōl) plural.bronchioles [L. bronchiolus, air passage]
One of the smaller subdivisions of the bronchial tubes. Bronchioles have no cartilage in their walls; they also have few glands in their mucosa.

respiratory bronchiole

The last division of the bronchial tree. Respiratory bronchioles are branches of terminal bronchioles and continue to the alveolar ducts, which lead to the alveoli.

terminal bronchiole

The next-to-last subdivision of a bronchiole, leading to the respiratory bronchioles.
Medical Dictionary, © 2009 Farlex and Partners


Small airways extending from the bronchi into the lobes of the lungs.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Such criteria were; alveolar generation, thickening in interalveolar septum, capillary hyperemia, hemorrhage, inflammatory cell infiltration, terminal bronchiole structure, terminal bronchiole debris, respiratory bronchiole wall structure, respiratory wall debris, alveolar structure and edema in vascular wall.
Also, the injuries sustained by the study animals endured are not consistent with bronchiolitis obliterans in humans given that the animal injuries are mostly of the nasal and upper respiratory track rather than the alveoli or bronchioles.
However, as fibrosis gets worse in either UIP/IPF or CHP with a UIP pattern, it tends to overrun the lobule, extending to encompass bronchioles, so in advanced disease, it is sometimes impossible to separate those entities (Figure 2, C; and see Discussion).
In Group II was observed an increased amount of the number and caliber of the bronchi and bronchioles (Figures 2D and 2E), decreased mesenchyme and the initial opening of the internal lumen of the bronchioles (Figure 2F).
Additionally, oral RGE treatment for 30 days prior to influenza virus infection significantly decreased the inflammation of the bronchioles compared to non-exposure.
ResultsIn the control group, normal alveolar duct, alveolar spaces and terminal bronchioles with regular size and shape of the alveoli were found (Figure-1).
However, compared to other avian influenza viruses, the attachment to epithelial cells by H7N9 in the bronchioles and alveoli of the lung was more abundant and the viruses attached to a broader range of cell types.
Bacterial respiratory colonization and subsequent inflammation probably play an important role in dilating the bronchioles and causing bronchiectasis--which leads to more colonization.
Alveoli were packed with serosanguineous mass and bronchioles revealed degeneration in lining epithelial cells.
Bronchiolitis obliterans, or "popcorn lung," is a rare, irreversible, debilitating lung disease in which inflammation and scarring obstruct the smallest airways, the bronchioles. There is no good treatment for the disease short of a lung transplant.
Although the disease was first described in 1835, long before microwave popcorn, most of the world had never before even heard of it.The irreversible condition, formally known as bronchiolitis obliterans, is an obstruction of the bronchioles 6 the smallest airways in the lungs.
A positive result by light microscopy was granular to diffuse red staining on the apical surface of epithelial cells in trachea, bronchi, and bronchioles and on alveolar cells.