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Paroxetine is a selective serotonin reuptake inhibitor effective in a once-daily administration regimen in the treatment of depression. In elderly patients (aged > or = 60 years) with major depression, short term (6 weeks) treatment with paroxetine produces clinical improvements significantly superior to those seen with placebo and similar to those with tricyclic antidepressant agents, mianserin and fluoxetine. There is evidence that paroxetine has positive effects on co-existing anxiety and does not precipitate agitation. Paroxetine has also shown potential in the symptomatic treatment of diabetic neuropathy; however, further clinical experience is needed to confirm this preliminary result. Short term paroxetine therapy is associated with fewer anticholinergic and CNS adverse effects, but generally more gastrointestinal disturbances, than tricyclic antidepressants and mianserin. Unlike the tricyclic agents, paroxetine does not significantly affect cardiovascular function or impair psychomotor performance. This tolerability profile should be particularly beneficial in elderly patients, who are generally more susceptible than younger patients to the anticholinergic and CNS adverse events associated with tricyclic antidepressant drugs, and in whom there is a higher prevalence of pre-existing cardiovascular disease. It also suggests an important potential advantage over tricyclic antidepressants in the setting of overdosage. Thus, primarily because of its better tolerability profile and potentially lower toxicity in overdosage and in patients with cardiovascular disease, paroxetine appears to be a more attractive option than tricyclic antidepressants for the treatment of depression in late life. Future research should attempt to define more fully the efficacy of paroxetine as long term prophylactic therapy for recurrent depression and to assess how its overall therapeutic profile compares with other selective serotonin reuptake inhibitors in the elderly. 相似文献
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X-ray powder diffraction, X-ray fluorescence, microscopy, X-ray absorption fine structure, and electron probe microanalysis were used to characterize ZrO2-MgO inert matrix fuel containing UO2 (as a fissile element and a Pu homolog) and Er2O3 as a burnable poison. A large composition range of MgO and ZrO2 was evaluated to determine total concentrations, local environment, phases present, phase mixing, and phase composition. It was found that most compositions of the material consist of two phases: MgO (periclase) and ZrO2 (cubic zirconia). The zirconia phase incorporates up to 5% (wt/wt) MgO and up to 20% and 10% (wt/wt) UO2 and Er2O3 respectively. This allows the fissile material and burnable poison to be incorporated into the zirconia crystal structure and defines the limits of this isomorphic substitution. The bond deformation due to the isomorphic substitution of uranium was determined by X-ray absorption fine structure. The MgO phase remains pure, which will enable design optimization of the overall thermophysical properties of the inert matrix fuel in regard to thermal diffusivity and thermal conductivity. This characterization data will be used in future studies to correlate the dissolution behavior of inert matrix material containing plutonium. 相似文献
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The contemporary challenge of leadership has been framed in terms of dealing authentically, ethically, and effectively with the complexity and uncertainty of organizational life. This article draws on research in the fields of psychology and philosophy to introduce practical wisdom as a new way to conceptualize optimal leadership practice. The authors propose that practically wise leaders can be effectively developed by using serious play techniques. Empirical data are presented to illustrate this proposition, and several implications for the field of consulting psychology are outlined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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In this paper we define a new structural parameter of polymers, and show how this may be employed. This parameter, for which only the structure and the density are needed, is the relative number of network bonds per unit volume; it is written Ner (basis 1 cm3), and it is used in conjunction with the average connectivity or connection number CN of the network atoms, where the word connection also refers only to network bonds. The relationship of these two numbers makes it possible to present a unified picture of all polymers, organic and inorganic, including such highly condensed networks as diamond. By plotting Ner against CN, the region in which inorganic and organic polymers occur can be seen. This is called the polymer zone, and it is evident that carbon polymers occupy only a small part of it. From this graph, an arbitrary measure of bond packing efficiency can be deduced for carbon polymers. In addition, the process of graphitization and carbonization can be followed graphically within the polymer zone. Ner is also related to certain physical properties such as bulk modulus, hardness, and cubical coefficient of expansion, which depend (among other things) on the tightness of bond arrangement. The resultant correlations can be used to predict the value of Ner required to achieve given values of these properties for the more rigid structures. 相似文献
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Alfalfa seeds are sometimes subjected to a scarification treatment to enhance water uptake, which results in more rapid and uniform germination during sprout production. It has been hypothesized that this mechanical abrasion treatment diminishes the efficacy of chemical treatments used to kill or remove pathogenic bacteria from seeds. A study was done to compare the effectiveness of chlorine (20,000 ppm), H2O, (8%), Ca(OH)2 (1%), Ca(OH)2 (1%) plus Tween 80 (1%), and Ca(OH)2 (1%) plus Span 20 (1%) treatments in killing Salmonella and Escherichia coli O157:H7 inoculated onto control, scarified, and polished alfalfa seeds obtained from two suppliers. The influence of the presence of organic material in the inoculum carrier on the efficacy of sanitizers was investigated. Overall, treatment with 1% Ca(OH)2 was the most effective in reducing populations of the pathogens. Reduction in populations of pathogens on seeds obtained from supplier I indicate that chemical treatments are less efficacious in eliminating the pathogens on scarified seeds compared to control seeds. However, the effectiveness of chemical treatment in removing Salmonella and E. coli O157:H7 from seeds obtained from supplier 2 was not markedly affected by scarification or polishing. The presence of organic material in the inoculum carrier did not have a marked influence on the efficacy of chemicals in reducing populations of test pathogens. Additional lots of control, scarified, and polished alfalfa seeds of additional varieties need to be tested before conclusions can be drawn concerning the impact of mechanical abrasion on the efficacy of chemical treatment in removing or killing Salmonella and E. coli O157:H7. 相似文献
50.
Holliday Robyn E.; Brainerd Charles J.; Reyna Valerie F. 《Canadian Metallurgical Quarterly》2011,47(2):442
A developmental reversal in false memory is the counterintuitive phenomenon of higher levels of false memory in older children, adolescents, and adults than in younger children. The ability of verbatim memory to suppress this age trend in false memory was evaluated using the Deese-Roediger-McDermott (DRM) paradigm. Seven and 11-year-old children studied DRM lists either in a standard condition (whole words) that normally produces high levels of false memory or in an alternative condition that should enhance verbatim memory (word fragments). Half the children took 1 recognition test, and the other half took 3 recognition tests. In the single-test condition, the typical age difference in false memory was found for the word condition (higher false memory for 11-year-olds than for 7-year-olds), but in the word fragment condition false memory was lower in the older children. In the word condition, false memory increased over successive recognition tests. Our findings are consistent with 2 principles of fuzzy-trace theory's explanation of false memories: (a) reliance on verbatim rather than gist memory causes such errors to decline with age, and (b) repeated testing increases reliance on gist memory in older children and adults who spontaneously connect meaning across events. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献