Results 251 to 260 of about 61,398 (311)

Regional distribution of ventilation-perfusion ratios in acute pulmonary embolism

Intensive Care Medicine, 1984
Regional ventilation perfusion ratios have been computed in 44 patients with acute pulmonary embolism with a gamma-camera using Krypton 81m, a short-life radionuclide delivered by inhalation and infusion. This noninvasive technique is performed during tidal breathing and can be easily repeated. High V/Q's are detected in the embolic regions and low V/Q'
M, Meignan, A, Harf, L, Cinotti
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Ventilation-perfusion ratio obtained by a noninvasive frequency response technique

Journal of Applied Physiology, 1976
Results of animal experiments using sinusoidal changes in inspired halothane concentration showed that the ratio of variation in end-expired concentration to the variation in inspired concentration reached a plateau in theBode diagram. With the help of an uptake and distribution model, the interpretation of the results showed that the level of the ...
A, Zwart, R C, Seagrave, A, Van Dieren
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Bronchospirometric studies of lung volumes, ventilation/perfusion ratios and diffusion

Journal of Applied Physiology, 1965
Bilateral bronchospirometric nitrogen washout studies were used for the first time to calculate ventilation/perfusion ratios for the well and poorly ventilated areas in individual lungs. Results were compared with washout studies on both lungs measured together. Data suitable for analysis were obtained from seven patients with chronic lung disease. It
E M, CREE, H K, RASMUSSEN, F, WRIGHT, J K, CURTIS   +3 more
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Ventilation-perfusion ratios and the pulmonary shunt

Bulletin of Experimental Biology and Medicine, 1980
Tests were carried out on 63 healthy persons aged 17–29 years, in the sitting position. The following parameters of lung ventilation were determined: Vd, phys/ Vt=30±0.6%,AaDO2=10±0.9 mm Hg, aADCO2/paCO2 was equal to the end-expiratory pCO2, i.e., to Pet,CO2=5.0±0.4 mm Hg,\(\dot Qva/\dot Qt\) (air)=2.3±0.3%,\(\dot Qs/\dot Qt\) (O2)=1.8±0.2%.
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Ventilation-perfusion ratio distributions by mass spectrometry with membrane catheters

Journal of Applied Physiology, 1982
We previously developed a quadrupole mass spectrometer system for measuring gas phase concentrations of multiple inert gases at trace levels. A new inlet with two silicone rubber membrane catheters now allows quantitative analysis of the inert gas concentrations in both blood and gas phase samples.
S M, Mastenbrook, J A, Dempsey, T A, Massaro   +2 more
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[Educational programs on ventilation-perfusion ratio].

Meditsinskaia tekhnika, 1995
The paper describes a learning programme for calculating the characteristics of arterial blood from the ventilation-perfusion ratios in the lungs by using a three-variable mathematical model of the lung. The lungs are presented as a set of three components which differ in ventilation and perfusion: 1) a fraction of ventilated and O2-perfused alveoles ...
A G, Chuchalin, G M, Sakharova, O N, Makretskaia   +2 more
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[Ventilation-perfusion ratios].

Der Anaesthesist, 1995
Knowledge of normal and impaired pulmonary gas exchange is essential to the anaesthesiologist. Analysis of an arterial blood sample allows evaluation of whether or not pulmonary gas exchange is normal. For this purpose comparison with the oxygenation index or the alveolar-arterial PO2 difference is helpful.
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[Pulmonary ventilation/perfusion ratio].

Journal de physiologie, 1988
The ratios of ventilatory (V) and perfusion (Q) flow rates in the lung are to a large extent responsible for the efficiency of gas exchange. In a simplified monocompartmental model of the lung, the arterial partial pressure of a given gas (Pa) is a function of several factors: the solubility of this gas in blood, its venous and inspired partial ...
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[Almitrine bismesylate and ventilation-perfusion ratios].

Revue des maladies respiratoires, 1986
Almitrine bismesilate (Vectarion) is characterised by its specific activity on carotid and aortic chemoreceptors. A simultaneous study of the ventilatory and blood gas changes in the anaesthetised dog has shown a dissociation between these two effects.
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Distribution of ventilation-perfusion ratios in pulmonary sarcoidosis.

Sarcoidosis, 1987
In 14 patients with advanced stage pulmonary sarcoidosis the distribution of regional ventilation-perfusion ratios (V/Q) was obtained by quantitative analysis of ventilation-perfusion single photon emission computed tomography (SPECT) of the lungs. In 6 patients normal V/Q distributions were found with a decreased DLCO in only one of them.
A, Zwijnenburg, C, Alberts, H M, Jansen, C M, Roos, H R, Marcuse   +4 more
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