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81.
Antigenotoxic effects of the phytoestrogen pelargonidin chloride and the polyphenol chlorogenic acid
Pelargonidin (PEL), a common anthocyanidin with estrogenic activity, was tested in HL-60 cells for its genotoxicity and possible antigenotoxic effects against 4-nitroquinoline 1-oxide (NQO), a potent mutagen and carcinogen which induces oxidative stress. To take into account potential interactions between phytochemicals within normal human nutrition, we evaluated a combination of PEL with the nonestrogenic phytochemical chlorogenic acid (CLA), one of the most abundant polyphenols in the human diet. PEL (< or = 2 microM) and CLA (< or = 800 microM) were nongenotoxic in the micronucleus test. We observed significant antigenotoxic effects against NQO with both compounds, but no additive interaction of PEL and CLA. Comet assay results showed a nonsignificant reduction in NQO-induced DNA damage with both compounds and their combination. Flow cytometric analysis of oxidative stress revealed significant protection against NQO-induced oxidative stress by PEL, CLA, and their combination. Furthermore, PEL and CLA prevented the NQO-induced reduction in GSH level. This could be a mechanism for the observed reduction in genotoxicity. In conclusion, the phytoestrogen PEL revealed antioxidative and antigenotoxic properties in HL-60 cells, but no significant additive interaction with the abundant nutritional polyphenol CLA under the tested conditions. 相似文献
82.
Knowledge generation is a cornerstone of new product development, and post‐project reviews (PPRs) are widely recognized as a facilitator of project‐to‐project learning. Empirical research on PPRs is sparse, so this paper describes four in‐depth exploratory case studies that look at how PPRs are conducted and the learning that can result. The results indicate that appropriately managed PPRs can make a significant contribution to knowledge generation and exchange. In addition, the study indicates the urgent need for more research into this important area. 相似文献
83.
84.
Rare-earth iron garnet films with in-plane anisotropy grown on (111)-oriented substrates can be used as magneto-optical indicator films for visualization of magnetic leakage fields in nondestructive evaluation. The influence of Faraday rotation, Faraday ellipticity, absorption and film thickness on the performance of a magneto-optical indicator film is investigated. A new optimization method is introduced and compared with the method of contrast optimization. The theory is experimentally verified and an application example is presented. 相似文献
85.
M. Pischetsrieder Ursula Gro? Christiane Schoetter 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1999,209(1):172-177
Two HPLC methods with diode array detection were used to separate Maillard products from milk components. The Maillard products 4-(β-d-galactopyranosyloxy)-2-hydroxy-2-methyl-2H-pyran-3(6H)-one (2), 1-[3-(β-d-galactopyranosyloxy)-2-furanyl]-1-ethanone (4), 4-(β-d-galactopyranosyloxy)-5-(hydroxymethyl)-2-methyl-3(2H)-furanone (5), isomaltol (7), maltol (9), 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one (6), and 5-hydroxymethyl-2-furfuraldehyde (8) were determined using a water-methanol gradient. Furthermore, 4,5-dihydroxy-2-(β-d-galactopyranosyloxy)-5-methyl-2-cyclopenten-1-one (3) was separated from the milk components by applying the interaction reagent octylamine. Several heated or processed milk samples were analyzed, and formation of the Maillard products was determined and quantified. Thus it was found that 2 and 3 are early products of the Maillard reaction in milk, whereas after prolonged heating 4, 5, and particularly 9 and 6 become more important. Compounds 7 and 8 were not detected, even if the samples were heated under stringent conditions. 相似文献
86.
We prove that any simplification order over arbitrary terms is an extension of an order by weight, by considering a related monadic term algebra called the spine. We show that any total ground-stable simplification order on the spine lifts to an order on the full term algebra. Conversely, under certain restrictions, a simplification ordering on the term algebra defines a weight function on the spine, which in turn can be lifted to a weight order on the original ground terms which contains the original order. We investigate the Knuth–Bendix and polynomial orders in this light. We provide a general framework for ordering terms by counting embedded patterns, which gives rise to many new orderings. We examine the recursive path order in this context. 相似文献
87.
Olaf A.M. Fisscher Klaasjan Visscher Alan Pearson Ursula Weisenfeld 《Creativity & Innovation Management》2001,10(4):251-258
Research and development departments in industrial firms may not take it for granted anymore that they are the only preferred supplier of research and development to the company of which they are a part. The growing need to be innovative and the increasing availability of innovative competencies on the market result in a pressure on these departments to become more business–like and to reconsider their sources of competitive advantage over other (potential) suppliers of research and development. Traditionally, scientific and technological knowledge and skills concerning the product were the prime source. Nowadays, managerial competencies and the ability to work for and with your clients and suppliers are becoming more important. To become a competitive business in a business, research and development departments should create the competencies that enable them to create value for their clients. This calls for good competence management, comprising management of human resources, information technology, and internal and external interfaces. In this paper we explore what it means and what it takes for research and development departments to implement competence management, elaborating it theoretically and describing a case of competence management in the research and development department of a European car company. 相似文献
88.
Prof. Dr.-Ing. Ursula Freundt Dr.-Ing. Sebastian Böning Eberhard Pelke Dipl.-Ing. 《Bautechnik》2021,98(10):736-744
Determination of object-specific traffic-load-models for existing road bridges based on traffic data For an assessment of the necessity, the efficiency and the prioritization of repair and upgrading measures for bridges, object-specific knowledge of structural stresses and structural conditions is indispensable. From the identification of traffic occupancy (quantity and quality) and the analysis of the structural reactions, statements on the current load-bearing capacity of an existing bridge will derived. A necessary data basis is the traffic data of the real traffic determined for the specific bridge. 相似文献
89.
Alexander Kutschera Ursula Schombel Dominik Schwudke Stefanie Ranf Nicolas Gisch 《International journal of molecular sciences》2021,22(6)
Lipopolysaccharide (LPS), the major component of the outer membrane of Gram-negative bacteria, is important for bacterial viability in general and host–pathogen interactions in particular. Negative charges at its core oligosaccharide (core-OS) contribute to membrane integrity through bridging interactions with divalent cations. The molecular structure and synthesis of the core-OS have been resolved in various bacteria including the mammalian pathogen Pseudomonas aeruginosa. A few core-OS structures of plant-associated Pseudomonas strains have been solved to date, but the genetic components of the underlying biosynthesis remained unclear. We conducted a comparative genome analysis of the core-OS gene cluster in Pseudomonas syringae pv. tomato (Pst) DC3000, a widely used model pathogen in plant–microbe interactions, within the P. syringae species complex and to other plant-associated Pseudomonas strains. Our results suggest a genetic and structural conservation of the inner core-OS but variation in outer core-OS composition within the P. syringae species complex. Structural analysis of the core-OS of Pst DC3000 shows an uncommonly high phosphorylation and presence of an O-acetylated sugar. Finally, we combined the results of our genomic survey with available structure information to estimate the core-OS composition of other Pseudomonas species. 相似文献
90.
In this paper we give an overview over a series of experiments to visualize and measure flow fields in the human vascular
system with respect to their diagnostic capabilities. The experiments utilize a selection of GPU-based sparse and dense flow
visualization algorithms to show the diagnostic opportunities for volumetric cardiovascular phase contrast magnetic resonance
imaging data sets. Besides classical hardware accelerated particle and line-based approaches, an extensible tublet-based visualization,
a four-dimensional volumetric line integral convolution and a new two-dimensional cutting plane tool for three-dimensional
velocity data sets have been implemented. To evaluate the results, several hearts of human subjects have been investigated
and a flow phantom was built to artificially simulate distinctive flow features. Our results demonstrate that we are able
to provide an interactive tool for cardiovascular diagnostics with complementary hardware accelerated visualizations.
Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users.
相似文献
Dieter SchmalstiegEmail: |