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At least 1,513 records · Page 84Linked to original sources
PubMed1974

Treatment of chronic hepatic encephalopathy with levodopa.

Three of six patients with chronic hepatic encephalopathy treated with levodopa showed a significant improvement. One patient was probably improved whilst the remaining two patients failed to show any benefit. Serial electroencephalography did not demonstrate significant changes. Treatment with levodopa was associated with an improvement in ;speed-based' tasks as assessed by computerized psychometry. A significant rise in cerebral oxygen consumption was found during levodopa therapy. Gastrointestinal side effects were dose limiting. It is concluded that a therapeutic trial of levodopa in patients with chronic hepatic encephalopathy is indicated when the response to conventional therapy has been poor.

Adult↗
PubMed1984

Effect of cimetidine on augmented gastric blood flow in duodenal ulcer patients.

Blood flow in the human stomach was measured during operation with a 85Krypton washout method which made simultaneous determinations of total blood flow and intramural flow distribution possible. The antrum and the corpus of the stomach could be investigated separately. Eleven patients with duodenal ulcer disease were studied during pentagastrin infusion and after the addition of cimetidine, 3 mg/kg bw, to evaluate the effect of the drug on augmented gastric blood flow. Eight recordings were made over the corpus of the stomach and three recordings over the antrum. Cimetidine caused a 66 +/- 5% decrease (mean +/- SE; range 56-86) in acid secretion and a 62 +/- 5% decrease (range 44-91) in the corpus mucosal blood flow within 15 minutes. Changes were only seen in the acid secreting part of the stomach while the antral circulation remained unaltered. It is concluded that the decrease in pentagastrin induced vasodilatation in the stomach seen after giving cimetidine was secondary to an inhibition of acid secretion.

Animals↗
PubMed1975

Variations in right and left coronary blood flow in man with and without occlusive coronary disease.

The relation of angiographically recognized coronary occlusion to regional myocardial blood flow has not been studied adequately in spite of its clinical significance. This is particularly important, as revascularization procedures, based on angiographic studies, are being performed with increasing frequency. To compare the severity of reduction in flow to the severity of coronary occlusion, regional myocardial blood flow (85-Kr washout) was measured in 34 patients. Selective coronary anteriograms were obtained using the Sones technique, and occlusions were graded as a percentage of luminal diameter. Of 26 right coronary arteries for which satisfactory arteriograms and coronary blood flow measurements were obtained, 16 were normal and 10 had significant stenosis (greater than 50%). Dominant right coronary arteries appeared to have high flows (67 plus or minus 6 ml min-minus1 per 100 g muscle) and a greater incidence of occlusion (10 of 20) than nondominant arteries, which had less flow (41 plus or minus 2 ml min-minus1 per 100 g muscle) and a lower incidence of occlusion (1 of 8). Coronary blood flow in 16 normal left coronary arteries was 84 plus or minus 5 ml min-minus1 per 100 g muscle and in 15 with 50 per cent or greater occlusion, 68 plus or minus 3 ml min-minus1 per 100 g muscle. Though coronary blood flow appeared reduced when lesions of both the right and left coronary arteries were present, a critical reduction was seen only when occlusion was greater than 90 per cent.

Adult↗
PubMed1981

Objective in vivo analysis of anti-smoking cigarette filters.

Cigarette filters have been introduced to reduce inhaled smoke and also as a means of breaking the smoking habit. Twelve volunteers smoked cigarettes through four ventilated anti-smoking filters (MD-4, Miles Laboratories) and one reference cigarette without an anti-smoking filter in a single-blind, crossover manner. The amount of smoke inhaled was monitored by a radiotracer technique using the isotope 81mkrypton. Compared to the reference cigarette the amount of isotope reaching the lung was reduced to 76%, 63%, 43%, and 37% for filters 1 to 4, respectively, which was less than the reduction to 70%, 40%, 30%, and 20% predicted by the manufacturers. In the case of filters 2, 3, and 4, the observed reductions in isotope inhalation were significant (p less than or equal to 0.01) but were also significantly less (p less than or equal to 0.01) than the manufacturers' predictions.

Adult↗
PubMed1977

Applications of ventilation lung imaging with 81mKrypton.

A method for the evaluation of regional lung ventilation using 81mKr eluted from a rubidium generator is described. The tracer distribution at equilibrium is a function of regional ventilation, not of volumes. The study can be performed on a wide range of patients, including unconscious and mechanically ventilated patients, and can be performed immediately following or concurrently with a perfusion study. Thus, precisely comparable ventilation and perfusion images can be obtained.

Humans↗
PubMed1985

Kr-81m ventilation imaging: clinical utility in suspected pulmonary embolism.

The results of Kr-81m/Tc-99m ventilation-perfusion (VP) lung scintigraphy were correlated with the results of pulmonary angiography for 74 patients suspected of having pulmonary embolism (PE). Among patients having a diagnostic scan, the sensitivity and specificity of scintigraphy were 91% and 94%, respectively. Also, 157 consecutive cases of Kr-81m/Tc-99m VP lung scintigraphy were reviewed, and the frequency of an indeterminate scan was found to be 22%. A similar frequency was found for VP scintigraphy with xenon-133. Of eight patients who had indeterminate scans due to the presence of a single VP mismatch, four were demonstrated to have PE by angiography. Kr-81m is an excellent agent for VP scanning in cases of suspected PE, offering accuracy in diagnosis as well as favorable physical properties.

Humans↗
PubMed1977

An implantable semiconductor beta-radiation detector.

An implantable beta-radiation detector suitable for the measurement of reginal blood flow in the experimental animal by the indicator clearance principle is described. A lithium-drifted silicon diode encapsulated in a stainless steel case is sutured over the site of interest. A suitable beta-emitting isotope, such as 85Kr in saline solution, is injected into the arterial supply and its calibrated against a mechanical system and showed excellent agreement up to 600 ml/100 g per min. At very high rates beyond the physiological range, flow was underestimated by a maximum of 10%. In vivo comparisons of myocardial blood flow assessed by the beta detector did not agree well with estimates of flow from a precordial counter or by the microsphere technique. Possible reasons are spatial heterogeneity of regional myocardial blood flow, the greatly different masses of tissue involved, or our inability to achieve sufficient numbers of spheres for accuracy in a 50-mg mass of tissue. The unit was still functional after 50 days in a chronic animal.

Animals↗