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991.
992.
OBJECTIVES: To better characterize intrarenal neuroblastoma. METHODS: We retrospectively reviewed the records of 5 children with neuroblastoma initially diagnosed as Wilms' tumor. RESULTS: Five patients, aged 11 months to 3.5 years, were preoperatively diagnosed as having intrarenal Wilms' tumor, prior to operative or histopathologic diagnosis of neuroblastoma. In 3 children the diagnosis of neuroblastoma involving the kidney was confirmed; in the fourth child subcutaneous metastatic disease precluded biopsy confirmation of the intrarenal tumor; and in the fifth child the kidney was severely displaced but not actually involved by neuroblastoma. All patients were hypertensive and 4 patients had elevated urinary catechol levels. Molecular genetic studies showed N-myc amplification in both patients who were evaluated. All patients had poorly differentiated histopathology. One patient is presently alive at 8 months with recurrent disease and another patient is free of disease 13 years after diagnosis. The remaining 3 patients died of the malignancy. CONCLUSIONS: Intrarenal neuroblastoma is a rare entity that clinically and radiographically may resemble Wilms' tumor. Our limited experience indicates that intrarenal neuroblastoma is an aggressive malignancy, and long-term survival is rare.  相似文献   
993.
994.
Early diagnosis of acute myocardial infarction is important to enable myocardial injury to be limited by means of various treatments. Monitoring of vessel patency with vector cardiography or continuous 12-lead ECG recording is a form of surveillance that has been widely accepted in Sweden. In post-reperfusion therapy monitoring, there is approximately 80 per cent agreement between monitoring ST-segment changes and acute coronary cardiography. For risk stratification of patients with unstable angina or non-Q-wave infarction, ST-segment monitoring manifests great predictive power which is further enhanced by its combination with the measurement of highly specific markers of myocardial injury. Computerised techniques for continuous monitoring of multiple ECG leads have contributed much to our understanding of the dynamics of acute coronary heart disease. Valuable prognostic information is available in real time, early identification of myocardial injury is possible, and treatment strategies can be based upon more reliable grounds.  相似文献   
995.
Accidental exposure to blood may represent a frightening experience for health care workers because of the risk of developing infectious diseases, such as hepatitis B and C virus and HIV infection. Recommendations for follow-up after occupational exposure to HIV- and hepatitis infected blood are presented. Post-exposure chemoprophylaxis decreases the risk of occupational HIV infection after percutaneous exposure and should be administered within two hours. Studies have shown that most accidents could have been avoided with better working routines during operations.  相似文献   
996.
997.
In the present study we compared the outcome of primary percutaneous coronary angioplasty (PTCA) (PTCA without prior or concomitant administration of thrombolytic drugs) in 82 consecutive patients with acute myocardial infarction (AMI) with the outcome of 82 AMI patients, who were treated with intravenous thrombolysis. The thrombolysis patients were prospectively matched to the angioplasty patients regarding age, sex, duration of symptoms and infarct localisation. The in-hospital mortality was 3.7% in the PTCA group versus 4.9% in the thrombolysis group. Thrombolysis-treated patients had increased use of diuretics and ACE-inhibitors as compared to PTCA-treated patients. The mean ejection fraction was 52 +/- 11% in the PTCA group versus 47 +/- 10% (p = 0.01) in the thrombolysis group. We conclude that initial Danish experience with primary PTCA is promising, and that this treatment may favourably affect the outcome of acute myocardial infarction.  相似文献   
998.
Evaluation of solar heat gain and daylight distribution through complex window and shading systems requires the determination of the bi-directional transmission distribution function (BTDF). Measurement of BTDF can be time-consuming, and inaccuracies are likely because of physical constraints and experimental adjustments. A general calculation methodology, based on more easily measurable component properties, would be preferable and would allow much more flexibility. In this paper, measurements and calculations are compared for the specific case of prismatic daylight-redirecting panels. Measurements were performed in a photogoniometer equipped with a digital-imaging detection system. A virtual copy of the photogoniometer was then constructed with commercial ray-tracing software. For the first time, an attempt is made to validate detailed bi-directional properties for a complex system by comparing an extensive set of experimental BTDF data with ray-tracing calculations. The results generally agree under a range of input and output angles to a degree adequate for evaluation of glazing systems. An analysis is presented to show that the simultaneously measured diffuse and direct components of light transmitted by the panel are properly represented. Calculations were also performed using a more realistic model of the source and ideal model of the detector. Deviations from the photogoniometer model were small and the results were similar in form. Despite the lack of an absolute measurement standard, the good agreement in results promotes confidence in both the photogoniometer and in the calculation method.  相似文献   
999.
In this paper, we investigate a multi-rate network in which wide-band calls are allowed to wait if insufficient resources are available at the time of the call arrival. On the link level, an analytical model is presented and simulations have been carried out on the network level. The results indicate that allowing a few wide-band calls to queue can give a significant improvement in performance in terms of network revenue , as well as a means to level out the blocking probabilities of the different traffic classes. This improvement becomes significant when the service discipline of the waiting calls (of different bandwidth requirements) is adaptive in the sense that longer queues get served first. This observation motivates the investigation of the impact of various buffer space assignment and queueing disciplines on network revenue and call blocking probabilities. The study of such mixed delay and queueing networks is motivated by its possible applications to traffic problems in future Broadband Integrated Services Digital Networks as well as in multi-rate cellular radio networks.  相似文献   
1000.
Heroin-abusing Danish prisoners remanded in custody were based on interviews grouped as either smoking dependent (n = 18) or intravenous dependent (n = 55). Intravenous users had a longer duration and earlier debut of abuse than users who smoked opiates. Only intravenous users had serious somatic complications. Both groups of opioid dependent prisoners were marked by severe psychosocial dysfunction and considerable psychiatric co-morbidity. The intravenous users were generally more affected than the smokers concerning social and psychiatric parameters and earlier criminality, perhaps due to their longer duration of abuse.  相似文献   
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