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41.
Summary Lidocaine, which was recently demonstrated to be a good pro-lipoperoxidant, was tested on in vitro PGs biosynthesis, and on arachidonate-induced arterial hypotension, in the rabbit. In the in vitro experiments, lidocaine alone was a poor stimulant of cyclo-oxygenase, but it enhanced significantly the cyclo-oxygenase activation of uric acid. In the rabbit, lidocaine lowered the i.v. arachidonate dose necessary to obtain a significant drop of blood pressure.  相似文献   
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Summary Polysaccharide fractions derived from a gram-negative proteus organism show strong anti-lipaemic activity of the order of 1000 times that of heparin. Analogous preparations from gram-positive organisms and mycobacteria show no such activity and some polysaccharide fractions from plant and animal tissues proved to have slight activity. None of these polysaccharides influenced the clotting of plasmain vitro.  相似文献   
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In this paper we focus on the effect of (i) deleting, (ii) restricting or (iii) not restricting seasonal intercept terms on forecasting sets of seasonally cointegrated macroeconomic time series for Austria, Germany and the UK. A first empirical result is that the number of cointegrating vectors as well as the relevant estimated parameter values vary across the three models. A second result is that the quality of out-of-sample forecasts critically depends on the way seasonal constants are treated. In most cases, predictive performance can be improved by restricting the effects of seasonal constants. However, we find that the relative advantages and disadvantages of each of the three methods vary across the data sets and may depend on sample-specific features. © 1998 John Wiley & Sons, Ltd.  相似文献   
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The peculiar object P/2010?A2 was discovered in January 2010 and given a cometary designation because of the presence of a trail of material, although there was no central condensation or coma. The appearance of this object, in an asteroidal orbit (small eccentricity and inclination) in the inner main asteroid belt attracted attention as a potential new member of the recently recognized class of main-belt comets. If confirmed, this new object would expand the range in heliocentric distance over which main-belt comets are found. Here we report observations of P/2010?A2 by the Rosetta spacecraft. We conclude that the trail arose from a single event, rather than a period of cometary activity, in agreement with independent results. The trail is made up of relatively large particles of millimetre to centimetre size that remain close to the parent asteroid. The shape of the trail can be explained by an initial impact ejecting large clumps of debris that disintegrated and dispersed almost immediately. We determine that this was an asteroid collision that occurred around 10 February 2009.  相似文献   
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The article provides an overview of the argument in Robert Scharff’s paper “Displacing epistemology: Being in the midst of technoscientific practice” (Scharff 2011), focusing on his central objective, to articulate a hidden ground of the current controversies in the philosophy of science and technology studies, between objectivism and constructivism, through a deeper confrontation with Heidegger’s legacy. The commentary addresses two aspects of Scharffs argument that deserve to be developed further, namely how it both criticizes and cultivates itself an ideal of the meta-knower, and how the idea of thinking from the perspective of life in Dilthey’s sense can be critically reflected through Heidegger’s later criticism. By rehearsing Heidegger’s understanding of truth as aletheia, and also his gradually increased criticism of the very concept of life, the commentary tries to show how Scharff’s intervention can in fact be strengthened against possible criticism.  相似文献   
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CO2在通过安全阀的排放过程中,形成的固体CO2在安全阀下游管道突扩处沉积,导致管路的堵塞和冻结,危害被保护系统的安全.为了寻求减少固体CO2在安全阀下游管道突扩处的沉积量和进一步避免管道堵塞的方法,利用拉格朗日模型对CO2气固两相紊流在突扩管内的流动和沉积特性进行计算,通过比较沉积率计算值与实验值,验证了计算结果的合理性;利用该模型分析了各种流动参数对流动和沉积特性的影响.结果表明,通过安全阀开启排放过程中生成的固体颗粒直径尽可能远离颗粒回流量的峰值区域(即颗粒直径0.04~0.07 mm,St数为3.2~9.8的区域),可以降低固体CO2的沉积量,从而避免管道的堵塞和冻结.具体可以通过设计适当的安全阀开启时最小流通截面面积做到.  相似文献   
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This article analyses the Danish 1909 celebrations of the centenary of Charles Darwin's birth on 12 February 1809. I argue that the 1909 meetings, lectures and publications devoted to Darwin and his theory of evolution by natural selection can be characterised by ambivalence: on the one hand, tribute to a great man of science who established a new view of nature and, on the other hand, scepticism towards the Darwinian mechanism of natural selection and the wider religious and political implications drawn from his theory. The article examines both professional and popular commemorative activities, focusing primarily on celebratory articles carried in widely circulated magazines and newspapers. I identify three types of interpretations of Darwin's ideas which I characterise as ‘radical’, ‘evangelical’ and ‘safe’ science. These different positions were closely linked to the political and cultural divisions of the periodical press. Moreover, my analysis of the popular press offers a solid basis for asserting that to most people Darwinism was associated with human evolution, primarily the relationship between man and apes, while more sophisticated discussions about the crisis of Darwinism prominent among naturalists played only a secondary role in the public arena. This article demonstrates the value of using newspapers as historical sources when looking for public images of Darwin, popular receptions of Darwinism and representations of science in general.  相似文献   
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