a 5-day-old female holstein calf was necropsied because of lethargy, recumbency and anorexia. at necropsy, multiple gross defects were evident in several organs, including unclosed sutures of skull bones, asymmetrical orbits, doming of the skull bones, hydrocephalus, hydranencephaly, cleft palate, brachygnathia, ventricular septal defect, mitral valve dysplasia and rudimentary lungs. on microsc...

Ovine pulmonary adenocarcinoma (OPA) was studied in the lungs of 15 naturally-affected sheep (9 with classical and 6 atypical lesions) by transmission electron microscopy. Two lung samples from normal sheep were used to develop the ultrastructural criteria. Pathologic lesions consisted of focal-multifocal to coalescent nodules or masses in the cranioventral or diaphragmatic lobes. Ultrastructur...

Pulmonary capillaries recruit when microvascular pressure is raised. The details of the relationship between recruitment and pressure, however, are controversial. There are data supporting 1). gradual homogeneous recruitment, 2). sudden and complete recruitment, and 3). heterogeneous recruitment. The present study was designed to determine whether alveolar capillary networks recruit in a variet...

Many pulmonary diseases preferentially affect the large airways or the alveoli. Although the mechanisms are often particular to each disease process, site-specific differences in leukocyte trafficking and the regulation of inflammation also occur. Differences in the process of margination, sequestration, adhesion, and migration occur that can be attributed to differences in anatomy, hemodynamic...

Alveolarization is the process by which the alveoli, the principal gas exchange units of the lung, are formed. Along with the maturation of the pulmonary vasculature, alveolarization is the objective of late lung development. The terminal airspaces that were formed during early lung development are divided by the process of secondary septation, progressively generating an increasing number of a...