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41.
The effects of beta-adrenergic blockade on cardiac transcapillary exchange were examined at rest and during sympathetic stimulation. Multiple indicator dilution experiments were carried out in closed-chest anesthetized dogs at rest and during carotid occlusion, either under basal conditions or after beta-adrenergic blockade with alprenolol. beta-Adrenergic blockade at rest had no effect on coronary flow or transcapillary exchange in comparison with the control situation, but it abolished the increase in coronary flow and in the permeability/surface area product for labeled sucrose produced by carotid occlusion. High coronary resistance values in beta-blocked animals with carotid occlusion were associated with a high degree of heterogeneity in capillary transit times, but the overall relation between coronary flow and the capillary permeability/surface area product was unchanged. The findings indicate that beta-blockade increases coronary resistance during sympathetic stimulation and, simultaneously, decreases the coronary blood flow and capillary permeability/surface area product while increasing the heterogeneity of capillary transit times.  相似文献   
42.
The use of mechanical ventilation in the Emergency Department requires adequate resources in order to maintain patient safety and avoid potential risks. Moreover, developments in technology require increased knowledge of mechanical ventilation techniques to address the complexity of decision-making involved. Organisational issues and system factors have the potential to negatively impact on the ability of the emergency service to provide optimum care to patients receiving mechanical ventilation. These issues include staffing and skill-mix, demand on emergency services, role-delineation, scope of practice, and current mechanisms for monitoring of quality and safety. Furthermore, in response to advances in ventilator technology, current education programs for both nursing and medical staff require review to ensure that they provide comprehensive information about the types of ventilation techniques now available and the relative risks and benefits associated with their application.This article is the second in a two-part series and explores the educational and organisational factors that impact upon safety and quality of care delivered to patients receiving mechanical ventilation in the emergency department. Recommendations for future policy development, curriculum review and reporting mechanisms to support further research in the application of mechanical ventilation in the emergency department are made.  相似文献   
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Summary Urinary output of endogenous monoamine oxidase (MAO) inhibitory activity, was significantly raised in serial samples collected across a migraine attack compared with collections during attack-free periods and in healthy controls, which did not differ from each other. There was a highly significant correlation in output between isatin, a major fraction of the MAO inhibitory activity, and output of the MAO inhibitory activity itself. However, although there was a tendency towards increased isatin excretion during migraine attacks, it failed to reach statistical significance.  相似文献   
45.
A patient of 12 suffering from aneurysmal cyst of the ischium was studied with traditional radiology, computed tomography (CT) and magnetic resonance imaging (MRI). The advantages of MRI in the study of this pathology compared to traditional radiography and CT are assessed. It was shown that the CT and MRI techniques are superior to standard X-ray examinations in anatomic definition and in evaluating the lesions's relationships with neighbouring structures and, in particular, that MRI is superior to CT in extension.  相似文献   
46.
Screening for early ovarian cancer   总被引:5,自引:0,他引:5  
Taylor  KJ; Schwartz  PE 《Radiology》1994,192(1):1
  相似文献   
47.
A 23-year-old man sustained an isolated popliteus tendon rupture while pushing a car. The diagnosis was established with the use of arthroscopy, electromyography, and Cybex testing. After the patient failed to respond to conservative therapy, the tendon rupture was surgically repaired. The patient had an uneventful recovery and returned to his preinjury level of athletic activity. Although popliteus tendon tenosynovitis as well as injury to the popliteus in association with other ligamentous knee injuries has been described, neither an isolated popliteus tendon rupture nor an arthroscopic evaluation of a popliteus tendon rupture has been reported.  相似文献   
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49.
A method is described for the chemical measurement of calcium oxalate and phosphate crystal formation in urine. The crystals were centrifuged, washed and the oxalate measured by an immobilised oxalate oxidase technique and the phosphate by a standard centrifugal analyser procedure. The methods proved precise and recoveries were good. Calcium oxalate crystal formation after evaporation is time-dependent and this parameter must therefore be standardised. Values for normal urinary calcium oxalate crystal concentration after concentration are given.  相似文献   
50.
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