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The severity of pulmonary embolism (PE) ranges from asymptomaticto cardiogenic shock with corresponding short-term mortalitybetween 2 and 95%. Whereas the former could be discharged earlyor managed entirely as outpatients using low-molecular-weightheparin, those with greater severity of PE require rapid echocardiographyto evaluate for indications for immediate thrombolysis or embolectomy.2,3However, most patients with PE fall between these two extremes.Patients with PE who do not initially present with life-threateningcriteria are usually admitted to a hospital ward where thosewith intermediate risk might experience a life-threatening recurrentepisode requiring emergent thrombolysis and critical care. Therefore,among patients with intermediate clinical severity, it is criticalto accurately identify those at risk for adverse medical outcome. Despite recent advances in risk stratification,  相似文献   
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BACKGROUND: Coronary vasculopathy is the main cause of cardiac graft failure. Because yearly coronary angiography is invasive in children, a non-invasive method for detecting graft vasculopathy is needed. The aim of this study was to test dobutamine-stress echocardiography in a pediatric population to determine its feasibility, safety and reliability in the detection of graft coronary artery disease. METHODS: Eighteen patients, aged 2 days to 16.8 years at transplantation (mean 8.4 years), underwent 44 dobutamine-stress echocardiography (DSE) exams, at a follow-up of 1.1 to 11.8 years (mean 5.1 years). Selective coronary angiography was performed for comparison. Echocardiographic recordings were obtained in 4 standard views of the left ventricle and measurements carried out within the frames of a 16-segment model. Segmental scores of contractility were obtained for each segment and a total segmental contractility index was calculated at each stage. RESULTS: All patients reached the maximum dose stage. Maximum heart rate was 57% to 90% of predicted maximum. Maximum systolic blood pressure reached 190 mmHg. Segmental scores were normal in 37 and abnormal in 7 cases. Echographic results were concordant with angiography in 82% and discordant in 18% of the cases (4 negative DSEs with minor angiographic lesions, 2 positive DSEs with normal angiography), but there was no significant angiographic lesion with normal DSE. CONCLUSIONS: DSE is a safe and highly feasible non-invasive technique in transplanted children. A normal DSE study successfully predicts the absence of significant coronary artery disease in the post-transplant population.  相似文献   
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The EUROCAT programme is a concerted action of the European Economic Community for the epidemiologic surveillance of congenital anomalies. Surveillance is based on a network of regional registries coordinated by a central registry. The programme started in 1979 and by 1987, 23 centres were participating, covering together more than 300,000 births per year. The surveillance process implies the selection of the anomalies possibly associated with environmental teratogens or mutagens, the definition of abnormal variations in the rate of these anomalies (the alarms), the establishment of base-line rate and the continuous monitoring of rate. The programme is evaluated by reference to four criteria: the sensitivity of the system in detecting teratogens or mutagens, the specificity of alarms, the rapidity in warning of alarm and in investigating their causes, and the programme efficiency expressed as its cost-utility ratio.  相似文献   
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The effect of cibenzoline succinate, a new antiarrhythmic agent, was studied on insulin secretion in rats. Experiments were performed both in vivo and in vitro using two preparations: the isolated perfused pancreas and isolated islets. In anaesthetized rats, cibenzoline was able to increase plasma insulin levels and to reduce glycaemia. These effects were observed at 1 mg/kg i.v. in fed rats and at 3 mg/kg i.v. in fasted rats. In the isolated pancreas perfused in the presence of a slightly stimulating glucose concentration (8.3 mM), cibenzoline (2 and 6 microM) elicited a progressive and sustained insulin response in a concentration-dependent manner. In the presence of a non-stimulating glucose concentration (4.2 mM), cibenzoline was ineffective at 2 microM and slightly increased basal insulin release at 6 microM. In isolated islets incubated with 8.3 mM glucose, cibenzoline (6 and 20 microM) caused a concentration-dependent stimulation of insulin release. It is concluded that cibenzoline stimulates insulin secretion by a direct action on pancreatic B cells in rats.  相似文献   
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Rheumatic heart disease continues to be relatively common in many parts of Africa, predominantly affecting young people. Special attention should be given to its prevention by the inexpensive methods that have proved effective elsewhere, and to this end assistance should be provided by the international community.  相似文献   
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In this text we briefly want to discuss the role of the arthrographic examination of the temporomandibular joint for detection of disc pathology. We will mention the normal anatomy and function of the temporomandibular joint, the technique for performing arthrograms and the classification of the most frequent disc pathology. This will be illustrated by some arthrographic examples of anterior disc displacement without reduction, disc perforation, and medial disc displacement. Finally the advantages of arthrography in comparison with other investigation techniques will be discussed.  相似文献   
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In this study, 50 patients were randomly assigned to treatment with 5-fluorouracil (FUra) or FUra plus high-dose continuous-infusion folinic acid. Five of 27 evaluable patients in the FUra group versus 10 of 21 patients in the FUra plus folinic acid arm of the study had objective partial remissions, P = 0.02. Time to progression was 3.9 months for FUra and 8.0 months for FUra and folinic acid, P = 0.006; however, median survivals (11.9 versus 14.5 months) were not different in this crossover study. Toxicity in both treatment arms was mild, although patients receiving FUra plus folinic acid experienced significantly more stomatitis than patients treated with FUra alone. This study suggests that high-dose, continuous-infusion folinic acid, which produces a steady-state level of biologically active folates of 10 microM, significantly increases the therapeutic activity of FUra.  相似文献   
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