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Thrombolytic therapy for unstable angina has not gained acceptance as a primary treatment for unstable angina (UA) despite the evidence showing a reduction in mortality when these agents are given for myocardial infarction. The purpose of this review is to examine the clinical value of thrombolytic therapy for UA. The multiple lines of evidence supporting intracoronary thrombus formation as a key mechanism in the pathogenesis of UA are reviewed. Studies examining the effect of thrombolytic therapy on angiographic endpoints have shown little effect on the extent of luminal narrowing, but do reveal a decrease in angiographically detected thrombus. Twelve randomized, controlled trials of thrombolytic agents in 611 UA patients with predefined clinical endpoints have been published. These trials varied widely in design and adjunctive therapy both in treated and control grops. Review of these trials show a tendency to fewer clinical events such as death, infarction, and need for revascularization in treated patients, with a corresponding increase in bleeding complications. Clinical efficacy of thrombolytic therapy cannot be excluded by the available data, perhaps in part because of insufficient numbers of patients treated. Determination of the net clinical value of thrombolytic therapy must await larger and more definitive trials.  相似文献   
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Psychological processes may play a role in the evaluation of the effectiveness of exercise and subsequent food intake. In order to further investigate this phenomenon, the effects of the timing of exercise relative to an eating opportunity were evaluated. Female undergraduate participants who were of average weight and did not exercise regularly were randomly assigned to one of three conditions (exercise before eating [n = 10], exercise after eating [n = 11], or no exercise [n = 12]). Expectations of the effectiveness of the exercise, value of dieting, and intake were assessed. Participants who exercised after eating had higher expectations of the effectiveness of the exercise than those who exercised before eating, while those who exercised before eating reported valuing dieting more than controls. No effects on intake emerged; therefore, there appears to be a disconnect between dieting appraisals and actual eating behaviour. The results are discussed in relation to theories on conflicting goals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In this paper, we present a performance analysis of network topologies for the optical core of IP-over-WDM networks with static wavelength routing. The performance analysis is focused on regular degree four topologies, and, for comparison purposes, degree three topologies are also considered. It is shown that the increase of the nodal degree from three (degree three topology with smallest diameter) to four (degree four topology with smallest diameter) improves the network performance if a larger number of wavelengths per link is available. However, the influence of wavelength interchange on the nodal degree gain is small. The performance of regular degree four topologies with smallest diameter is also compared with the performance of mesh–torus topologies (which are also degree four topologies), and it is shown that the blocking probability of degree four topologies with smallest diameter is about two orders of magnitude lower than the blocking probability of mesh–torus topologies. It is also presented a performance comparison of WDM-based networks with nodal degrees ranging from two to five and it is shown that the increase of the nodal degree from two to three leads to high nodal degree gains, while de increase of the nodal degree from four to five leads to low nodal degree gains. These results show that degree three and degree four topologies are very attractive for use in the optical core of IP-over-WDM networks.  相似文献   
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The present work consisted of the supplementation of macaroni with fish protein concentrate (FPC) at the levels of 5, 10, 15, and 20% in relation to wheat flour. The FPC was obtained from eviscerated and deboned trairas (Hoplias malabaricus), using boiling ethanol as a solvent at a pH range of 5.5 to 6.0. The FPC showed desirable aspects such as bright color, no off-flavor, high levels of protein (84.3 g/100 g) and lysine (484 mg/g N) and low levels of fat (0.4 mg/100 g) and moisture (8.6 g/100 g). The macaroni became slightly dark in color with increasing additions of FPC. Nevertheless, the 20% level was the only one not accepted by the testing panel, in terms of color and flavor. Weanling Wistar rats were used in the biological assay to measure the macaroni protein quality at the different supplementation levels. Analyses of PER, NPR, NPU, digestibility and retained carcass N were carried out. The protein quality of the macaroni was improved by the addition of FPC. The level of 10% was similar to the casein and no subsequent improvement in the protein quality was notified with higher levels of FPC. Due to its high lysine content, the FPC is a promising supplement for cereals. From the nutritional and sensory aspects, the 10% level of FPC was the most satisfactory for macaroni supplementation.  相似文献   
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In a stripping process conducted under vacuum where the gas is dispersed in the liquid mixture as very small bubbles (microbubbles), the contribution of the interfacial tension to the pressure inside a bubble is significant. As a result, the bubble does not expand significantly approaching the liquid free surface, even if the pressure drop in the gas is considerable comparatively to the pressure outside the bubble. This behaviour certainly determines the mass transfer rate mainly in the upper portion of the bubbling pool. In the present study a simplified model of the mass transfer process is proposed for this situation. One important conclusion is obtained from the predictions for the system pentane / n-paraffins in operations conducted under a pressure of 300 N m−2: the amount of solute removed from the liquid is lower when microbubbles are injected in the liquid although the interfacial area per unit volume of gas is very high.  相似文献   
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The objective of this study was to monitor the stability of anthocyanin and phenolic compounds contained in two formulations of blackberry jam (traditional and low-sugar) during storage. For that purpose, jams were prepared with varying amounts of hydrocolloids and investigated as to pH, total soluble solids, water activity, total acidity, total anthocyanins and total polyphenols. In order to accompany and assess the levels of phenolic compounds and colour (L*, a* and b*) changes, the samples were stored for 180 days at two different temperatures (10 and 25 °C). The Arrhenius model was used to determine the relationship between the reaction rate (k) at the different storage temperatures, yielding activation energy values of 19 and 12 kcal/mol and Q 10 values of 3.0 and 2.0 for traditional and low-sugar jams, respectively. The results show that by the end of the storage time investigated, the anthocyanin compounds had been partially degraded, with the greatest loss being observed in traditional jam stored at 25 °C. Colour stability was also lower in traditional jam as compared to the low-sugar product.  相似文献   
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