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排序方式: 共有394条查询结果,搜索用时 15 毫秒
21.
Kamil Musilek Dr. Ondrej Holas Jan Misik Miroslav Pohanka Dr. Ladislav Novotny Vlastimil Dohnal Dr. Veronika Opletalova Kamil Kuca Dr. 《ChemMedChem》2010,5(2):247-254
Acetylcholinesterase (AChE) reactivators are crucial antidotes to organophosphate intoxication. A new series of 26 monooxime‐monocarbamoyl xylene‐linked bispyridinium compounds was prepared and tested in vitro, along with known reactivators (pralidoxime, HI‐6, obidoxime, trimedoxime, methoxime, K107, K108 and K203), on a model of tabun‐ and paraoxon‐, methylparaoxon‐ and DFP‐inhibited human erythrocyte AChE. Although their ability to reactivate tabun‐inhibited AChE did not exceed that of the previously known compounds, some newly prepared compounds showed promising reactivation of pesticide‐inhibited AChE. The acute toxicity of the novel compounds was also determined. Docking studies using tabun‐inhibited AChE were performed for three compounds of interest. The structure–activity relationship (SAR) study confirmed the apparent influence of the xylene linkage and carbamoyl moiety on the reactivation ability and toxicity of the agents. 相似文献
22.
Veronika Kaufmann Siegfrid Scherer Ulrich Kulozik 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2010,5(42):59-64
Die ESL-Technologie stellt nach der H-Milch eine weitere Entwicklung mit hohem Zusatznutzen in Bezug auf Haltbarkeit und Vorratshaltung
dar, wovon sowohl Handel als auch Verbraucher gleicherma?en profitieren k?nnen. Im Vergleich zum herk?mmlich pasteurisierten
Produkt bringt das ESL-Konzept entscheidende Vorteile hinsichtlich der Haltbarkeit der Milch mit sich, wirkt sich dabei aber
kaum oder nur geringfügig auf die für den Verbraucher entscheidenden bzw. wertrelevanten Produkteigenschaften aus. ESL-Produkte
sind in diesem Sinne also nicht nur „l?nger haltbar”, sondern unserer Einsch?tzung nach auch „l?nger frisch”. Dass gerade
die Produktcharakteristika der ESL-Milch den Wünschen der Verbraucher entgegenkommen, zeigt sich an der stetig steigenden
Nachfrage nach diesen Produkten und dem damit einhergehenden Absatzrückgang von herk?mmlich pasteurisierter Frischmilch. Die
Verbraucher haben also durch ihr Kaufverhalten in den letzten Jahren bereits deutlich gemacht, dass sie der ESL-Milch durchaus
positiv gegenüberstehen und sich mit diesem Produktkonzept keineswegs „get?uscht” fühlen, was die hier zusammengefassten Fakten
eindeutig untermauern. 相似文献
23.
Turchik Jessica A.; Karpenko Veronika; Hammers Dustin; McNamara John R. 《Canadian Metallurgical Quarterly》2007,38(2):158
The rising costs of new psychological tests, increased frequency of test revisions, and difficulty receiving authorization and reimbursement from managed care companies make it increasingly difficult for practitioners to provide the best standard of care to clients when conducting psychological and neuropsychological assessments. Practitioners, especially those in low-income and rural areas, may struggle with handling these practical realities while maintaining ethical standards in conducting psychological assessment. Suggestions for how to manage practical challenges faced by practitioners who provide psychological assessments, such as selecting tests when authorization or reimbursement by a third-party payer is restricted or denied, purchasing psychological tests on a budget, and providing assessments with a limited number of qualified staff are discussed. The authors also provide recommendations for the future prevention of these challenges through work with test developers, test publishing corporations, third-party payers, political action groups, and the psychology profession itself. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
Veronika Kondratieva Seung-Woo Seo 《Communications Letters, IEEE》2007,11(2):149-151
Authentication based on the Merkle tree has been proposed as an energy efficient approach in a resource constrained sensor network environment. It replaces complicated certificate verification with more power efficient hash computations. While previous works assumed complete binary Merkle tree structures, which can be used efficiently only in sensor networks with a specific number of sensor nodes, we investigate incomplete Merkle trees to support any number of sensors. For the incomplete Merkle tree, we demonstrate that an optimal structure can be found through mathematical analysis and simulation. A novel tree indexing scheme is also proposed to reduce communication overhead and save sensors resources during authentication 相似文献
25.
Veronika Ostatná 《Electrochimica acta》2008,53(11):4014-4021
In proteomics and biomedicine fast techniques applicable for preliminary tests of the protein properties and structural changes are sought. Methods of electrochemical analysis have been little utilized in these fields. We show that using constant current chronopotentiometric stripping peak H, minute amounts of denatured and reduced bovine serum albumin (BSA) can be easily discriminated from native BSA. Peak H, which is due to catalytic hydrogen evolution, is greatly enhanced in the presence of non-denaturing concentrations of guanidinium chloride. The course of BSA reduction and denaturation can be followed and traces of the damaged protein can be detected in native BSA samples. 相似文献
26.
27.
Petr Zimcik Miroslav Miletin Veronika Novakova Kamil Kopecky Zuzana Dvorakova 《Dyes and Pigments》2009,81(1):35-39
Zinc tetrapyrazinoporphyrazines comprising different numbers of pyridin-2-yl and tert-butylsulfanyl substituents were prepared by the statistical condensation of two precursors – 5,6-bis(tert-butylsulfanyl)pyrazine-2,3-dicarbonitrile (A) and 5,6-dipyridin-2-yl-pyrazine-2,3-dicarbonitrile (B). The ensuing zinc tetrapyrazinoporphyrazines were chromatographically separated on silica column and characterized. Adjacent (AABB) and opposite (ABAB) isomers were not separated. The prepared zinc tetrapyrazinoporphyrazines did not differ in their Q-band position but the B-band position was shifted hypsochromically for compounds bearing more pyridyl units; in addition, a weak band at 450–520 nm decreased with increasing number of pyridyl substituents. Singlet oxygen quantum yields (ΦΔ in the range 0.69–0.53) decreased with increasing number of pyridyl units on the macrocyclic core, while fluorescence quantum yields showed the reverse tendency (ΦF in the range 0.22–0.26). 相似文献
28.
An Integrative Model of Mobile Phone Appropriation 总被引:1,自引:0,他引:1
Werner Wirth Thilo von Pape Veronika Karnowski 《Journal of Computer-Mediated Communication》2008,13(3):593-617
The evolution of mobile communication devices and services has taken up a dynamic that makes any prognosis in the field almost impossible. Whereas part of this dynamic may remain inscrutable, we believe that a much higher degree of explanation can be achieved by systematically paying closer attention to the process of appropriation. To seize upon this potential, we present an integrative model to analyze mobile phone appropriation (the "MPA model").
The model is based on existing theoretical approaches of the quantitative "adoption" paradigm (namely, Innovation Diffusion Theory and Theory of Planned Behavior) as well as the mostly qualitative research paradigm devoted to "appropriation" (Cultural studies and Frame Analysis), with the Uses-and-Gratifications approach playing a role on both sides. The model has been developed, operationalized and empirically applied in the context of mobile phone appropriation; however, with certain modifications it can be adapted to other information and communications technology (ICT) innovations. 相似文献
The model is based on existing theoretical approaches of the quantitative "adoption" paradigm (namely, Innovation Diffusion Theory and Theory of Planned Behavior) as well as the mostly qualitative research paradigm devoted to "appropriation" (Cultural studies and Frame Analysis), with the Uses-and-Gratifications approach playing a role on both sides. The model has been developed, operationalized and empirically applied in the context of mobile phone appropriation; however, with certain modifications it can be adapted to other information and communications technology (ICT) innovations. 相似文献
29.
Harald Rohm und Veronika Veits 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1989,189(6):538-543
Zusammenfassung Die in den USA entwickelte sensorische Texturprofilanalyse stellt die aussagestärkste Methode zur quantitativen und qualitativen Bewertung der Texturunterschiede von Lebensmitteln dar. Vor der Anwendung in Regionen mit anderen Konsumgewohnheiten bedarf sie jedoch einer entsprechenden Adaptierung. Mitteilung 1 berichtet über modifizierte standardisierte Intensitätsskalen zur quantitativen Einstufung der mechanischen Textureigenschaften Festigkeit, Brüchigkeit, Kaubarkeit, weichelastisches Verhalten, Viskosität und Adhäsivität. Die Anpassung an das österreichische Lebensmittelspektrum erfolgte mittels rheologischer Vorprüfungen potentieller Standardpunkte und anschließender Fixierung der Normskalen durch ein geschultes Prüferpanel unter guter Korrelation zwischen instrumentellen und sensorischen Prüfungen.
Adaption of sensory texture profile analysis 1. Scaling of mechanical properties
Summary Texture profile analysis, originally developed in the United States, represents the most complete system of both quantitative and qualitative sensory texture measurements of foodstuffs. Due to regionally varying habits of consumption, an adequate adaptation is necessary prior to application. This paper deals with the evaluation of the mechanical properties firmness, brittleness, chewiness, gumminess, viscosity and adhesiveness. Modifications of standard rating scales for typical Austrian food materials are reported. Rheological examination of commodities was followed by final establishment of standard scales with a trained panel. Good correlation between instrumental and sensory results was obtained.相似文献
30.
Dr. Kornelia Hardes Dr. Gero L. Becker Dr. Yinghui Lu Dr. Sven O. Dahms Susanne Köhler Dr. Wolfgang Beyer Prof. Kirsten Sandvig Dr. Hiroyuki Yamamoto Prof. Iris Lindberg Lisa Walz Dr. Veronika von Messling Dr. Manuel E. Than Prof. Wolfgang Garten Prof. Torsten Steinmetzer 《ChemMedChem》2015,10(7):1218-1231
New peptidomimetic furin inhibitors with unnatural amino acid residues in the P3 position were synthesized. The most potent compound 4‐guanidinomethyl‐phenylacteyl‐Arg‐Tle‐Arg‐4‐amidinobenzylamide (MI‐1148) inhibits furin with a Ki value of 5.5 pM . The derivatives also strongly inhibit PC1/3, whereas PC2 is less affected. Selected inhibitors were tested in cell culture for antibacterial and antiviral activity against infectious agents known to be dependent on furin activity. A significant protective effect against anthrax and diphtheria toxin was observed in the presence of the furin inhibitors. Furthermore, the spread of the highly pathogenic H5N1 and H7N1 avian influenza viruses and propagation of canine distemper virus was strongly inhibited. Inhibitor MI‐1148 was crystallized in complex with human furin. Its N‐terminal guanidinomethyl group in the para position of the P5 phenyl ring occupies the same position as that found previously for a structurally related inhibitor containing this substitution in the meta position, thereby maintaining all of the important P5 interactions. Our results confirm that the inhibition of furin is a promising strategy for a short‐term treatment of acute infectious diseases. 相似文献