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21.
The pharmacokinetics and dose proportionality of fexofenadine, a new non-sedating antihistamine, and its enantiomers were characterized after single and multiple-dose administration of its hydrochloride salt. A total of 24 healthy male volunteers (31 +/- 8 years) received oral doses of 20, 60, 120 and 240 mg fexofenadine HCl in a randomized, complete four-period cross-over design. Subjects received a single oral dose on day 1, and multiple oral doses every 12 h on day 3 through the morning on day 7. Treatments were separated by a 14-day washout period. Serial blood and urine samples were collected for up to 48 h following the first and last doses of fexofenadine HCl. Fexofenadine and its R(+) and S(-) enantiomers were analysed in plasma and urine by validated HPLC methods. Fexofenadine pharmacokinetics were linear across the 20-120 mg dose range, but a small disproportionate increase in area under the plasma concentration-time curve (AUC) (< 25%) was observed following the 240 mg dose. Single-dose pharmacokinetics of fexofenadine were predictive of steady-state pharmacokinetics. Urinary elimination of fexofenadine played a minor role (10%) in the disposition of this drug. A 63:37 steady-state ratio of R(+) and S(-) fexofenadine was observed in plasma. This ratio was essentially constant across time and dose. R(+) and S(-) fexofenadine were eliminated into urine in equal rates and quantities. All doses of fexofenadine HCl were well tolerated after single and multiple-dose administration.  相似文献   
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Intergranular and transgranular chemistries of hot-pressed and sintered silicon carbides were investigated by Auger electron spectroscopy. Results indicated major differences in grain-boundary compositions between the two. Hot-pressed silicon carbide displayed a complex intergranular chemistry. Sintered silicon carbide displayed grain facets that were free of impurities and additives. The observed intergranular chemistries for both silicon carbides are discussed in terms of their relation to the processing methods.  相似文献   
24.
The microstructure of a series of solid state extruded polyethylene fibres was examined by wide- and small-angle X-ray scattering. By measuring absolute intensities using a two dimensional position sensitive detector, accurate values of the small-angle invariant for anisotropic samples were obtained. This measurement coupled with wide-angle X-ray scattering and d.s.c. permitted determination of the density of the noncrystalline component. The use of a two phase model for solid state extruded polyethylene is justified if consideration is given to the effective densities of the crystalline and noncrystalline phases, which change with deformation. The effective density of the crystalline phase decreases by 1% (0.999–0.990 g cm?3) from the unextruded billet compared to a 36 draw ratio extrudate, while the noncrystalline phase density increases by 6% (0.84–0.89 g cm?3). These changes lead to an overall decrease in the mean squared electron density fluctuation of 63%. The average axial crystallite length measured by wide-angle X-ray scattering increases with extrusion draw ratio while the SAXS long period decreases and weakens considerably. These observations and the electron microscopy results from the previous paper, (Polymer, 1982, 23, 1069), are fully consistent with the key features of the Peterlin model of fibre microstructure.  相似文献   
25.
The use of titanium in production automobiles: Potential and challenges   总被引:1,自引:0,他引:1  
Titanium offers a number of attractive features for use in high-production-volume automobiles; however, high cost has been a barrier to application, thus far. This article discusses the potential and challenges for the use of titanium in the family automobile. A.M. Sherman earned his Ph.D. in metallurgy at the Massachusetts Institute of Technology in 1972. He is currently senior staff technical specialist at Ford Motor Company. Dr. Sherman is a member of TMS. C.J. Sommer earned his B.S. in metallurgical engineering at University of Pittsburgh in 1982. He is currently manager of automotive marketing at Timet. F.H. Froes earned his Ph.D. in physical metallurgy at Sheffield University in 1967. He is currently the director of the Institute for Materials and Advanced Processes at the University of Idaho. Dr. Froes is also a member of TMS.  相似文献   
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It was prepared new child's medicinal form, the tablets "Valcophene" for making a wider variety of pediatric preparation's. It is studied the influence of "Valcophene" on the functional state of alimentary canal in experiment on rat's. Results investigation's are testified to absence of ulcerative action in new child's preparations. Studying influence in liver functional state is provided for new children's preparation "Valcophene" too. The chronic experiment is showed that "Valcophene" didn't influence on liver in experimental animals.  相似文献   
27.
Hurricanes and tropical storms are severe threats to coastal properties, settlements, and infrastructure. Airborne light detection and ranging (lidar) surveys conducted before and after storm events allow detailed analysis of coastal geomorphologic and sediment volumetric changes and have been proved very useful in the study of coastal changes. Traditionally, most studies use the pixel-based differencing method to quantify the spatial extent and magnitude of coastal changes based on sequential lidar surveys. This research presents a graph theory-based approach and associated software tools for representing and quantifying storm-induced damages to buildings, beaches and sand dunes, coastal vegetation canopy, and infrastructure. Generation of elevation difference grids, construction of local contour trees, and derivation of semantic properties are key components of the new algorithm for change object detection and extraction. An ontology and taxonomy are proposed to classify change objects into different types of coastal damages in terms of their semantic properties. This method has been successfully applied to assess damages of Hurricane Ike to the Bolivar Peninsula on the Texas Gulf Coast based on pre- and post-storm airborne lidar data and colour infrared aerial photographs.  相似文献   
28.
There is wide interpatient variability in toxicity to chemotherapeutic drugs and a lack of routine clinical tests for prospectively identifying patients at risk of developing toxicity from chemotherapy. An empirically driven MS strategy has been developed to monitor liver-derived plasma proteins as potential biomarkers of early toxicity. Multiple reaction monitoring (MRM) has been used to assess 46 candidate peptides from 18 liver-derived proteins. Following an iterative process of assay design, optimisation and assessment we selected 29 MRM assays (median CV 4.6%, range 1.2-11.6%) and monitored changes in levels of plasma proteins from a small number of colorectal cancer (CRC) patients undergoing chemotherapy. We demonstrated MRM assay robustness, and show that patients undergo minor elevation in plasma proteins when profiled on Day 3 of the chemotherapeutic regime. The MRM assays were in general agreement with 2-D DIGE-based quantitation from the same patient samples. The data supports the application of MRM-based methods as facile, highly reproducible, medium-throughput techniques that warrant expanded investigation for clinical utility in identifying patients at risk of developing chemotoxicity.  相似文献   
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82 female undergraduates were assigned to 1 of 4 experimental groups—predict-request, information-request, predict only, and request only—in which requested tasks involved writing a counterattitudinal essay or singing over the telephone. In 3 experiments, Ss overpredicted the degree to which their behavior would be socially desirable and these errors of prediction proved to be self-erasing. Having mispredicted a given behavior, Ss were likely to have these predictions confirmed in later behavior, indicating that prediction of a behavioral sequence evokes a specific cognitive representation of that sequence which is subsequently accessed. Results demonstrate the strong effects on behavior of engaging in prebehavioral cognitive work. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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