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11.
A highly vascular petroclival meningioma supplied by tentorial branches of the internal carotid artery was embolized by temporary balloon occlusion of the parent vessel distal to the tumor, followed by obliteration of the tumor vascularity with polyvinyl alcohol particles. Subsequently, in vivo proton spectroscopy showed necrosis of a large portion of the tumor and helped determine the timing of surgery. Both innovative techniques considerably facilitated the subsequent radical excision of the tumor with no neurological morbidity.  相似文献   
12.
A process model of dual fluidized bed gasification is presented based on mass- and energy balances. The model further covers the evaluation of thermodynamic equilibrium states. The gasification is investigated for the special case that CaO/CaCO3 is used as bed material allowing selective transport of CO2 from the gasification reactor to the combustion reactor by repeated carbonation and calcination. Experimental data are used to determine the model parameters. An empirical approach towards the kinetics of fuel conversion allows prediction of process behaviour at varied fuel water content. The selective transport of CO2 results in high H2 contents in the produced syngas. The lower operating temperatures in the gasification reactor increase the efficiency of energy conversion. The results are in agreement with experimental data and show the thermodynamic limitations of the technology.  相似文献   
13.
This paper evaluates the impact of climate change, as projected by two Global Climate Models (GCMs) on the occurrence of extreme precipitation events in the Upper Thames River Basin in the Canadian province of Ontario. The modelling approach presented herein involves a two-stage process of generating daily weather data followed by disaggregation to an hourly time step of select variables for some events. Monthly change fields for three weather variables (maximum temperature, minimum temperature, and precipitation) were obtained from the output of two GCMs. The historical data set is modified by applying change fields to the weather variables simultaneously and then using this as the driving data set for an improved K-nearest neighbour weather-generating model. Weather sequences representative of climatic conditions in 2050 were simulated. Disaggregation of precipitation data is carried out using a new method that is a hybrid key site approach. A distinct practical advantage of the approach presented here is that extreme wet and dry spells are simulated, which is crucial for evaluation of effective flood and drought management policies for the basin.  相似文献   
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根据C.B.Goeldner公司的生产经验介绍了集聚纱在质量和生产成本上的优势,以及集聚纱在机织、针织和染整等后道工序中应用时与传统环锭纱的比较。  相似文献   
15.
Fisch.  W 《国际纺织导报》2000,(3):30-32
高质量、高成本的产品生产需要能与生产过程同步的现代化生产监视系统。生产监视系统有相应的工艺方案,方案包括每一不同的生产步骤以使生产管理人员能事先预测各种突发事件。本文介绍了在织造和织前准备过程中使用的现代化光电监视系统 。  相似文献   
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More than 600 cases of ovarian tumors were analyzed for histological type, age of patient, bilateral occurrence, mobility and malignant degeneration in restant ovaries. Tumors of germinal epithelial origin show the highest incidence (24%) of malignant degeneration, tumors of germ cells the lowest (3,5%). Incidence of malignant degeneration increases in relation to the age of the patient from 2% (and under 30 years) to 36,5% (60-70 years). Each form of tumor has its typical age peak, which is about 20 years higher for carcinomas than for their benign counterpart. Bilateral ovarian tumors are malignant in 29%, one-sided only in 13%. Among freely movable ovarian tumors, only 6% enclose a malignant tumor, among adhaerent ones 34%. The examination of the prognosis of granulosacell-tumors, dysgerminomas and teratoblastomas is based on a larger material.  相似文献   
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A combined cholestatic-hepatocellular injury and noncaseating granulomas occurred in two patients 1 and 4 weeks after phenylbutazone therapy. Both patients were jaundiced, one had a macular rash, and both had peripheral blood eosinophilia. Symptoms and signs subsided, and abnormal findings from tests of hepatic function rapidly returned to normal following withdrawal of the drug. Sections of liver biopsy specimens 6 months later showed no granulomas or other pathologic changes. Previously reported cases are reviewed.  相似文献   
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