Search results for "Respiratory Physiology"
showing 10 items of 363 documents
Sympathetic nervous activity and the pressor effect of noradrenaline under chronic?-?-adrenoceptor blockade with labetalol in hypertension
1983
In 14 patients with essential hypertension, the influence of the alpha- and beta-adrenoceptor blocking drug labetalol on blood pressure, heart rate, plasma renin, plasma noradrenaline and pressor effect of exogenous noradrenaline was investigated during long-term treatment. During the initial four weeks of treatment, labetalol at a dose of 400 mg/day showed a slight effect only on supine blood pressure, whereas upright blood pressure was already lowered effectively after the second week of treatment (p less than 0.01). An increase in the mean dose to 850 mg/day had an additional blood pressure-lowering effect (p less than 0.001), whereby a preferential decrease of the orthostatic blood pres…
Subtype-Specific Desensitization of Human Endothelin ETA and ETB Receptors Reflects Differential Receptor Phosphorylation
1997
Endothelins regulate blood pressure in mammals through G protein-coupled receptors. Two receptor subtypes, ETA and ETB, exist which differ by their agonist profiles. Here we show subtype-specific differences in the inactivation of these endothelin receptors. Using a modified inositol phosphate accumulation assay, we found that stimulation of ETA by endothelin-1 results in sustained activation of the subtype, retaining >30% of its initial activity even 20 min after agonist administration, whereas the ETB rapidly deactivated after agonist stimulation, losing >80% of its initial activity within 5 min after endothelin application. The discrepancy in receptor inactivation is reflected by subtype…
Mitochondrial aldehyde dehydrogenase (ALDH-2)--maker of and marker for nitrate tolerance in response to nitroglycerin treatment.
2008
The hemodynamic and anti-ischemic effects of nitroglycerin (GTN) are rapidly blunted as a result of the development of nitrate tolerance. Long-term nitrate treatment also is associated with decreased vascular responsiveness caused by changes in intrinsic mechanisms of the tolerant vasculature itself. According to the oxidative stress concept, increased vascular superoxide and peroxynitrite production as well as an increased sensitivity to vasoconstrictors secondary to activation of protein kinase C as well as vascular NADPH oxidases contribute to the development of tolerance. Recent experimental work has defined new tolerance mechanisms, including inhibition of the enzyme that bioactivates …
Regurgitant flow in apparently normal valve prostheses: improved detection and semiquantitative analysis by transesophageal two-dimensional color-cod…
1990
In 128 patients with apparently normally functioning prosthetic valves ( n = 136) in the aortic position ( n = 79) and the mitral position ( n = 57), the prevalence of transprosthetic regurgitant flow was studied by use of transthoracic and transesophageal two-dimensional color-coded Doppler echocardiography. With the transthoracic approach, regurgitant flow was detected in early systole or diastole for 28% of the mitral prostheses and for 29% of the aortic prostheses. With transesophageal color-coded Doppler echocardiography, regurgitant jets were visualized for 95% of the mitral prostheses and for 44% of the aortic prostheses. In 40% of the Bjork-Shiley prostheses and 88% of the St. Jude …
Adaptive Lung Ventilation (ALV) Evaluierung eines neuen closed loop-gesteuerten Beatmungsalgorithmus bei Eingriffen in �berstreckter Seitenlage
1996
The lateral decubitus position is the standard position for nephrectomies. There is a lack of data about the effects of this extreme position upon respiratory mechanics and gas exchange. In 20 patients undergoing surgery in the nephrectomy position, we compared a new closed-loop-controlled ventilation algorithm, adaptive lung ventilation (ALV), which adapts the breathing pattern automatically, to the respiratory mechanics with conventionally controlled mandatory ventilation (CMV). The aims of our study were (1) to describe positioning effects on respiratory mechanics and gas exchange, (2) to compare ventilatory parameters selected by the ALV controller with traditional settings of CMV, and …
"Table 29" of "Properties of hadronic Z decays and test of QCD generators"
1992
N-jet production rates (in percent) corrected for charged and neutral particles.
"Table 25" of "Properties of hadronic Z decays and test of QCD generators"
1992
N-jet production rates (in percent) corrected for charged particles only.
"Table 26" of "Properties of hadronic Z decays and test of QCD generators"
1992
N-jet production rates (in percent) corrected for charged particles only.
"Table 30" of "Properties of hadronic Z decays and test of QCD generators"
1992
N-jet production rates (in percent) corrected for charged and neutral particles.
"Table 31" of "Properties of hadronic Z decays and test of QCD generators"
1992
N-jet production rates (in percent) corrected for charged and neutral particles.