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981.
982.
Levels of cefuroxime in bronchial secretion were measured in 49 patients requiring bronchoscopy for diagnostic purposes. Patients were randomly allocated to one of 4 groups which differed with respect to the size (750 mg or 1.5 g) and number (1 or 7) of intravenous doses of cefuroxime given approximately 1 hour prior to sampling. Levels of cefuroxime achieved after administration of all 4 dosages were sufficient to exceed the MIC values for the major chest pathogens. Penetration of cefuroxime into bronchial secretion was also found to be dose-related. 相似文献
983.
Tested several aspects of restraint theory using 89 female college students in a 2–3 between-Ss design. The ice cream consumption of overweight and normal-weight restrained and unrestrained eaters was measured during a taste test. Prior to the taste test, half the Ss received a milkshake preload. Results reveal significant Weight by Restraint, Weight by Preload, and Restraint by Preload interactions. Unrestrained eaters consumed less after the preload than without it, whereas restrained eaters ate more. Overweight Ss ate less after the preload than without it, whereas normal-weight Ss ate slightly more. Among overweight Ss, unrestrained eaters ate more than restrained eaters, whereas among normal-weight Ss, the reverse was true. The significant Weight by Preload and Restraint by Preload interactions possibly reflect psychometric problems in the restraint scale. Numerically equivalent scores may indicate less "true" restraint in overweight than in normal-weight Ss. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
984.
985.
This paper presents a modified approach to solve state estimation problems of nonlinear dynamic systems involving noise free, uncorrelated and correlated state and measurement noise processes. The basic approach makes use of the matrix minimum principle together with the Kolmogorov and Kushner's equations to minimize the error-variance, taken to be the estimation criterion. The filtering equations obtained for nonlinear systems with white noise process are exact, but for non-white noise processes the results obtained are approximate.
For systems with polynomial or product types non-linearities, the proposed algorithms can be evaluated without the need of approximation under the assumption that the estimator errors are Gaussian. Such an assumption is significantly different from the most commonly used assumption that the state is Gaussian. Simulation results obtained from the proposed filtering algorithms are compared to various other approximate nonlinear filters. The results indicate the superiority of the proposed filter over those of other filters investigated. 相似文献
986.
987.
S?ren Christensen 《Sequential Analysis》2017,36(1):33-37
988.
Hong Zhang Charlotte Jacobsen Lars Saaby Pedersen Morten Würtz Christensen Jens Adler‐Nissen 《European Journal of Lipid Science and Technology》2006,108(3):227-238
In this study, four margarine hardstocks were produced, two from enzymatically interesterified fats at 80 and 100% conversion, one from chemically randomized fat and one from physically mixed fat. These four hardstocks, blended with 50% sunflower oil, were mainly used for the production of table margarines in a pilot plant. Storage stability studies were carried out at storage temperatures of 5 and 25 °C for 12 wk. Margarines from the enzymatically interesterified fats were compared to the margarines produced by the conventional methods (chemical interesterification and physical blending) and to selected commercial margarines. The changes in the chemical properties of the products, including peroxide values (PV), tocopherols, free fatty acids, volatile oxidation products, and sensory evaluation, were examined during storage. It was observed that the margarine produced from the chemically interesterified fat had higher PV in weeks 4, 8 and 10 than the margarines produced from the enzymatically interesterified fats and the physically blended fat. These differences were not caused by different contents of tocopherols in the hardstocks. The differences between the processes for chemical and enzymatic interesterification, including further treatment stages, might be responsible for the development of a high PV in the margarine produced from the chemically interesterified fat. However, the contents of volatiles did not show the same tendency as observed for PV for the margarines stored at 25 °C during 12 wk. Storage at 25 °C accelerated oxidation compared to storage at 5 °C. The content of δ‐ and γ‐tocopherols decreased faster than the content of α‐ and β‐tocopherols during storage. This phenomenon was only affected by storage time, not by storage temperature. Sensory analysis did not show consistent differences between the produced margarines and commercial margarines, and no hydrolysis occurred for these four margarines during storage. The margarines produced from the enzymatically interesterified fats had low PV and a similar taste and smell compared to the margarine produced from the chemically interesterified fat. 相似文献
989.
Z Cai A Bettaieb NE Mahdani LG Legrès R Stancou J Masliah S Chouaib 《Canadian Metallurgical Quarterly》1997,272(11):6918-6926
The interference of tumor necrosis factor-alpha (TNF) signaling processes with the acquisition of tumor resistance to TNF was investigated using the TNF-sensitive human breast carcinoma MCF7 cell line and its established TNF-resistant variant (R-A1). The resistance of R-A1 cells to TNF correlated with a low level of p55 TNF receptor expression and an absence of TNF signaling through TNF receptors. Stable transfection of wild-type p55 receptor in R-A1 resulted in enhancement of p55 expression and in partial restoration of TNF signaling, including nuclear factor-kappaB (NF-kappaB) activation. However, the transfected cells remained resistant to TNF-induced apoptosis. Northern blot analysis revealed a comparable induction of manganous superoxide dismutase and A20 mRNA expression in p55-transfected cells and in sensitive MCF7 cells, making it unlikely that these genes are involved in the resistance to TNF-mediated cytotoxicity. While TNF significantly stimulated both neutral and acidic sphingomyelinase (SMase) activities with concomitant sphingomyelin (SM) hydrolysis and ceramide generation in MCF7, it failed to trigger these events in TNF-resistant p55-transfected cells. In addition, the basal SM content was significantly higher in sensitive MCF7 as compared to the resistant counterparts. Furthermore, the TNF-resistant cells tested could be induced to undergo cell death after exposure to exogenous SMase or cell-permeable C6-ceramide. This study also shows that TNF failed to induce arachidonic acid release in p55-transfected resistant cells, suggesting that an alteration of phospholipase A2 activation may be associated with MCF7 cell resistance to TNF. Our findings strongly suggest a role of ceramide in the mechanism of cell resistance to TNF-mediated cell death and may be relevant in elucidating the biochemical nature of intracellular messengers leading to such resistance. 相似文献
990.
Electronic mail (e-mail) offers the potential for near-instantaneous transfer of messages and files across thousands of miles. The same message can be sent simultaneously to multiple recipients and forwarded without retyping. Messages can be sent or read at any time, eliminating "telephone tag," and, because the system is paperless, lost, blurred, and incomplete, facsimile transmissions can be minimized. Additionally, e-mail is less expensive than overnight letter services or long-distance faxes. All healthcare epidemiologists should enter the information superhighway using e-mail. This article provides basic information needed to understand and begin using e-mail. 相似文献