Diffusion capacity

Chest constriction impaired carbon monoxide diffusion capacity decrease in lung function without exercise... 

A suspected diagnosis of COPD should be based on the patient s symptoms and/or history of exposure to risk factors. Spirometry is required to confirm the diagnosis. The presence of a postbronchodilator FEV,/FVC ratio less than 70% [the ratio of FEV, to forced vital capacity (FVC)] confirms the presence of airflow limitation that is not fully reversible.1,2 Spirometry results can further be used to classify COPD severity (Table 12-1). Full pulmonary function tests (PFTs) with lung volumes and diffusion capacity and arterial blood gases are not necessary to establish the diagnosis or severity of COPD. 

Decrease in lung capacity, alveolar volume, and diffusing capacity for carbon monoxide values remained depressed for at least 72 h after last exposure. Persistent inflammation of proximal portion of alveolar ducts and adjacent alveoli. 

Diffusing capacity A test dose of carbon A low DLco tnay be... 

Changes in pulmonary function have been observed in a variety of species after short-term exposure to ozone, including alterations in the elastic behavior of the lungs, increased resistance to flow, and decreased carbon monoxide diffusion capacity. 

Complicated pneumoconiosis (PMF) is associated with a reduction in ventilatory capacity, low diffusing capacity, abnormalities of gas exchange, low arterial oxygen tension, pulmonary hypertension, and premature death ... 

A short-term study of guinea pigs exposed to zinc oxide fume 3 hours/day for 6 days at the threshold limit value (TLV) of 5mg/m revealed pulmonary function changes and morphologic evidence of small airway inflammation and edema. Pulmonary flow resistance increased, compliance decreased, and lung volumes and carbon monoxide diffusing capacity decreased. Some of these changes persisted for the 72-hour duration of postexposure follow-up. 

In this expression, 3 represents the increase factor of vertical diffusion due to the plume. Gaussian plume or dispersion models are based on standard deviations of the plume dimensions (crx, cry, oz). These represent a measure of the diffusive capacity of the atmosphere. They are dependent on the turbulence conditions of the atmosphere, the vertical temperature gradient (which helps to establish atmospheric turbulence in the vertical direction) and the transporting distance. 

Metallisation of fibres is not only a physical process determined by absorption capacity of the fibres for the metal and diffusion capacity of the metal in the fibre structure, but also depends on chemical parameters such as chemical structure of the fibres, presence of functional groups, reactivity of the fibre and the metal, oxidation state of the metal and the presence, necessity and reactivity of supporting chemicals (e.g. reducing agent). Therefore, it was necessary first to study metallisation at different types of fibres in order to investigate which structure is most useful for further research. In this respect, viscose, cotton, natural silk and polyacrylonitrile fibres were investigated because of their different structure and properties and their availability in the New Independent States of the former Soviet Union (Uzbekistan, Kazakhstan, Kyrgyzstan). 

Gehr, P., M. Bachofen, and E.R. Weibel. 1978. The normal human lung ultrastructure and morphometric estimation of diffusion capacity. Respir. Physiol. 32 121-140. 

Diffusing capacity for carbon monoxide (measurement of alveolar gas exchange)... 

Costa DL, Kutzman RS. 1985. Compensatory increase in diffusing capacity and alveolar surface area in the rat as a response to acrolein injury. Am Rev Respir Dis 131(4 Suppl.) A200. 

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