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P Lipponen S Aaltomaa M Eskelinen M Ala-Opas VM Kosma 《Canadian Metallurgical Quarterly》1998,34(3):237-243
Selective antagonists to the Type 3 serotonin receptor (5HT3) in combination with corticosteroids are now considered the standard of care for the prevention of emesis from moderately to highly emetogenic chemotherapy. Here we address issues of optimal dose, schedule and route of administration of four currently available selectable 5HT3 antagonists. This paper utilizes an evidence based medicine approach to the literature regarding this class of drugs, emphasizing the results large, randomized, controlled trials to make formal recommendations concerning optimal use of this important new class of anti-emetic agents. We conclude that for each drug there is a plateau in therapeutic efficacy at a definable dose level above which further dose escalation does not improve outcome. Furthermore, a single dose is as effective as multiple doses or continuous infusion, and finally, emerging data demonstrate that the oral route is equally efficacious as the intravenous route of administration, even with highly emetogenic chemotherapy. 相似文献
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Trifluoroethanol (TFE) is often used to increase the helicity of peptides to make them usable as models of helices in proteins. We have measured helix propensities for all 20 amino acids in water and two concentrations of trifluoroethanol, 15 and 40% (v/v) using, as a model system, a peptide derived from the sequence of the alpha-helix of ribonuclease T1. There are three main conclusions from our studies. (1) TFE alters electrostatic interactions in the ribonuclease T1 helical peptide such that the dependence of the helical content on pH is lost in 40% TFE. (2) Helix propensities measured in 15% TFE correlate well with propensities measured in water, however, the correlation with propensities measured in 40% TFE is significantly worse. (3) Propensities measured in alanine-based peptides and the ribonuclease T1 peptide in TFE show very poor agreement, revealing that TFE greatly increases the effect of sequence context. 相似文献
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The methodology for developing intelligent integrated computer-aided design and manufacturing systems based on object-oriented principles is discussed. The ways in which the application of these principles affects the nature of these systems are reviewed. The implementation of an automated, intelligent, and flexible computer-integrated-manufacturing (CIM) system prototype using an object-oriented programming environment (Smalltalk-80, Version 4.0) is detailed. A CIM system includes CAD, a process planner, and an inspection planner. Each of these components is discussed individually 相似文献
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Dynamic mechanical test methods have been widely employed for investigating the structures and viscoelastic behavior of polymeric materials to determine their relevant stiffness and damping characteristics for various applications. Randomly oriented short banana/sisal hybrid fiber–reinforced polyester composites were prepared by keeping the volume ratio of banana and sisal 1 : 1 and the total fiber loading 0.40 volume fraction. Bilayer (banana/sisal), trilayer (banana/sisal/banana and sisal/banana/sisal), and intimate mix composites were prepared. The effect of layering pattern on storage modulus (E′), damping behavior (tan δ), and loss modulus (E″) was studied as a function of temperature and frequency. Bilayer composite showed high damping property while intimately mixed and banana/sisal/banana composites showed increased stiffness compared to the other pattern. The Arrhenius relationship has been used to calculate the activation energy of the glass transition of the composites. The activation energy of the intimately mixed composite was found to be the highest. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2168–2174, 2005 相似文献