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41.
1. Vinorelbine produced a dominant metabolite (M1) after incubation with rat liver microsomes. 2. Several major metabolites other than M1 were identified by HPLC in bile and faeces of rat after intravenous administration. 3. The structures of the major metabolites were identified as 15,16-epoxyvinorelbine (M1), 11'-hydroxyvinorelbine (M2), 19'-hydroxyvinorelbine (M3a), 15,16-epoxy-10'-hydroxyvinorelbine (M3b) and 10'-hydroxyvinorelbine (M4) by comparison of HPLC retention times and by extensive analyses of two-dimensional NMR and hybrid MS/MS spectra. 相似文献
42.
Gaertner Lowell; Iuzzini Jonathan; Witt Melissa Guerrero; Ori?a M. Minda 《Canadian Metallurgical Quarterly》2006,90(3):426
Four experiments examined whether group formation and positive in-group regard require interaggregate comparison as the in-group-requires-an-out-group assumption of the metacontrast principle implies. The authors fostered novel social aggregates with or without a contrasting aggregate with which members could compare and varied intra-aggregate factors (interaction or interdependence). Regardless of whether interaggregate comparison was feasible, the intra-aggregate factors increased the perceived entitativity of the aggregate and positive regard toward the aggregate (i.e., social attraction and cooperation among members). Mediation analyses were consistent with the possibility that the intra-aggregate factors promoted entitativity, which in turn promoted in-group regard. These data suggest that group formation and in-group regard have intragroup origins and do not require comparison with a contrasting social aggregate. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
PURPOSE: To evaluate the risk of temporary or permanent internal carotid artery occlusion. METHODS: In 156 patients intraarterial balloon test occlusion in combination with a stable xenon-enhanced CT cerebral blood flow study was performed before radiologic or surgical treatment. All 156 patients passed the clinical balloon test occlusion and underwent a xenon study in combination with a second balloon test. Quantitative flow data were analyzed for absolute changes as well as changes in symmetry. RESULTS: Fourteen patients exhibited reduced flow values between 20 and 30 mL/100 g per minute, an absolute decrease in flow, and significant asymmetry in the middle cerebral artery territory during balloon test occlusion. These patients would be considered at high risk for cerebral infarction if internal carotid artery occlusion were to be performed. With one exception they belonged to a group (class I) of 61 patients who showed bilateral or ipsilateral flow decrease and significant asymmetry with lower flow on the side of occlusion. The other 95 patients, who showed a variety of cerebral blood flow response patterns including ipsilateral or bilateral flow increase, were at moderate (class II) or low (class III) stroke risk. In contrast to these findings, exclusively qualitative flow analysis failed to identify the patients at high risk: a threshold with an asymmetry index of 10% revealed only 16% specificity whereas an asymmetry index of 45% showed only 61% sensitivity for detection of low flow areas (< 30 mL/100 g per minute). CONCLUSION: For achieving a minimal hemodynamic related-stroke rate associated with permanent clinical internal carotid artery occlusion we suggest integration of a thorough analysis of quantitative cerebral blood flow data before and during balloon test occlusion. 相似文献
44.
H. Atmanspacher J. Kurths H. Scheingraber R. Wackerbauer A. Witt 《Open Systems & Information Dynamics》1992,1(2):269-289
Measures of complexity and meaning in nonlinear dynamical systems are presented, applied to specific examples, and compared with each other. A basic conceptual and operational equivalence of both kinds of measures is described. This equivalence substantiates earlier indications by Atlan and Grassberger for a close relationship between complexity and meaning. Both concepts are suggested as candidates to demonstrate the necessity of certain extensions and modifications required to update several habitual regulative principles of the exact sciences. 相似文献
45.
46.
Witt A. Wegener M. Lyssenko V.G. Klingshirn C. Wingen G. Iyechika Y. Jager D. Muller-Vogt G. Sitter H. Heinrich H. MacKenzie H.A. 《Quantum Electronics, IEEE Journal of》1988,24(12):2500-2506
Illumination of CdS at room temperature with the green (514 nm) line of an Ar+ laser may lead to intrinsic photothermal-induced absorption optical bistability. If the samples are covered with two metal contacts resulting in a small slit, the additional feedback introduced through the photocurrent by Joule's heat may lead to a reduction of the necessary optical input power. In particular, CdS single-crystal platelets, CdS epitaxial layers, or CdS evaporated layers contacted with either Au or In are used. The experimental characteristics are compared with detailed model calculations, which explain deviations from ideal behavior. Special emphasis is laid upon the modulator characteristics (i.e. controlling photonics by electronics) and the possibility of controlling electronics by photonics 相似文献
47.
Colour CRT displays have the potential both to enhance the presentation of primary flight information and also to improve the interface between complex avionic systems and the flight deck crew. This paper describes research to explore this potential, and reports the opinions of a wide range of pilots who experienced such displays in the working environment. 相似文献
48.
M. Witt 《Computers & Structures》1984,18(1):41-45
In this paper the solution of the problem of interaction of a plate with a two parameter elastic foundation is presented. Vertical displacements of rectangular plates having free edges resting on a heterogeneous elastic foundation have been analysed by using of finite element method. The heterogeneity of the foundation caused by the orthotropy has been taken into account when forming the equations of equilibrium and variable thickness of the foundation by approximating it by Haar's functions. The obtained results have been compared with the results for a homogeneous foundation. 相似文献
49.
Klaus Witt 《Color research and application》1987,12(3):128-134
In four of the five CIE color regions, the correlation of perceptibility of color differences and colorimetric measures is studied for painted samples at threshold. Sample pairs resulting in three-dimensional color differences ranging from zero to just clearly perceptible were used. The variability of color-difference ellipsoids is shown for single observers and for observer groups. Randomisation of mean results by a Monte-Carlo method produces deviation ellipsoids that describe shells of uncertainty inherent in the data. Interobserver and inter-group variability turns out to be widely covered by random noise, but the variances leave some stability of ellipsoid shapes. Color-difference formulas should be able to predict color differences within the shells of uncertainty. 相似文献
50.
The aim of this 1 week study was to compare the biologic effects induced by Betaseron and AVONEX using their approved dose, route, and schedule. Sixteen healthy volunteers were randomly assigned to receive either a single i.m. dose of AVONEX (6 million International Units [MIU]) or, every other day s.c. doses of Betaseron (8 MIU). Common side effects associated with interferon-beta (IFN-beta) treatment and biologic response parameters (neopterin, beta2-microglobulin, interleukin-10 [IL-10], and MxA protein levels in blood) were measured. Ibuprofen was administered to all subjects throughout the study. Fever, chills, and myalgia occurred most frequently and with the greatest severity between 6 and 12 h after the first dose of either IFN-beta. Despite the additional dosing of subjects in the Betaseron group, the incidence, duration, and severity of the side effects were not significantly different from those in the AVONEX group. Biologic response parameters reached similar maximum concentrations in both treatment groups. In the Betaseron group, neopterin and beta2-microglobulin levels remained significantly greater than baseline throughout the 7 day study, whereas those in the AVONEX group were elevated only through day 5. Betaseron treatment significantly increased IL-10 levels above baseline, but AVONEX treatment did not. The overall induction of neopterin, beta2-microglobulin, and IL-10 (as measured by area under the concentration-time curve) was significantly greater in the Betaseron group than the AVONEX group (p = 0.031). The results of this study demonstrate that the approved Betaseron dosing regimen, in combination with ibuprofen use, provided a significantly greater and more consistently elevated biologic response compared with that of AVONEX and did so with a side effects profile comparable to that of once a week AVONEX dosing. 相似文献