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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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Valerii S. Kozlov Elena P. Yausheva Svetlana A. Terpugova Mikhail V. Panchenko Dmitriy G. Chernov Vladimir P. Shmargunov 《International journal of remote sensing》2014,35(15):5722-5741
A comprehensive experiment on the study of dynamics of optical and microphysical characteristics of submicron aerosols in the near-ground air layer was carried out in June–August of 2012 under conditions of extremely strong smoke haze originating from vast forest fires in Siberia. Variations of the spectral angular scattering coefficients and the degree of linear polarization in the visible wavelength range are studied, as well as the mass concentrations of dry fractions of aerosol and black carbon, relative content of black carbon (BC fraction), single scattering albedo, particle size distribution function, complex refractive index of the particulate matter, and parameter of condensation activity of aerosol. Peculiarities of differences between optical and microphysical characteristics of near-ground aerosol in smoke haze and under smokeless conditions are revealed. This study is important for validation of results of remote sensing of the composition of smoke haze and background atmosphere obtained from satellite data and sun photometric measurements at the Aerosol Robotic Network (AERONET). 相似文献