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911.
Damodara Reddy V Padmavathi P Gopi S Paramahamsa M Varadacharyulu NCh 《Indian journal of clinical biochemistry : IJCB》2010,25(4):419-424
The effect of Emblica officinalis fruit extract (EFE) against alcohol-induced hepatic damage in rats was investigated in the present study. In vitro studies showed that EFE possesses antioxidant as well nitric oxide (NO) scavenging activity. In vivo administration of alcohol (5 g/kg b.wt/day) for 60 days resulted increased liver lipid peroxidation, protein carbonyls, nitrite plus nitrate levels. Alcohol administration also significantly lowers the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase and reduced glutathione as compared with control rats. Administration of EFE (250 mg/kg body weight) to alcoholic rats significantly brought the plasma enzymes towards near normal level and also significantly reduced the levels of lipid peroxidation, protein carbonyls and restored the enzymic and non-enzymatic antioxidants level. This observation was supplemented by histopathological examination in liver. Our data indicate that the tannoid, flavonoid and NO scavenging compounds present in EFE may offer protection against free radical mediated oxidative stress in rat hepatocytes of animals with alcohol-induced liver injury. 相似文献
912.
M. A. Fallah V. M. Myles T. Kr��ger K. Sritharan A. Wixforth F. Varnik S. W. Schneider M. F. Schneider 《Biomicrofluidics》2010,4(2)
Accurately mimicking the complexity of microvascular systems calls for a technology which can accommodate particularly small sample volumes while retaining a large degree of freedom in channel geometry and keeping the price considerably low to allow for high throughput experiments. Here, we demonstrate that the use of surface acoustic wave driven microfluidics systems successfully allows the study of the interrelation between melanoma cell adhesion, the matrix protein collagen type I, the blood clotting factor von Willebrand factor (vWF), and microfluidic channel geometry. The versatility of the tool presented enables us to examine cell adhesion under flow in straight and bifurcated microfluidic channels in the presence of different protein coatings. We show that the addition of vWF tremendously increases (up to tenfold) the adhesion of melanoma cells even under fairly low shear flow conditions. This effect is altered in the presence of bifurcated channels demonstrating the importance of an elaborate hydrodynamic analysis to differentiate between physical and biological effects. Therefore, computer simulations have been performed along with the experiments to reveal the entire flow profile in the channel. We conclude that a combination of theory and experiment will lead to a consistent explanation of cell adhesion, and will optimize the potential of microfluidic experiments to further unravel the relation between blood clotting factors, cell adhesion molecules, cancer cell spreading, and the hydrodynamic conditions in our microcirculatory system. 相似文献
913.
Lillian V?Ortiz-FournierEmail author Eulalia?Márquez Felix Rogelio?Flores Juan C?Rivera-Vázquez Pablo A?Colon 《知识管理研究与实践》2010,8(3):203-215
This research is part of a broader investigation to analyse the processes followed by the Caguas Municipality at the Commonwealth of Puerto Rico in an effort to develop the characteristics of a ‘Smart City’ as an example of sustainable development. We describe the integration of the educational institutions’ initiatives and the municipal government strategic plan to contribute to the knowledge and intellectual capital that brings sustainability to the city. An actor's model was designed to represent this integration. The conceptual framework was based on the concepts of knowledge production and sharing as applied to the collaboration between critical representative actors. Field research consisting of in-depth interviews was performed to ascertain the integration processes and their relationship with such processes of knowledge production and sharing. The results showed that the governance paradigm implemented is already empowering the citizens to contribute with intellectual capital that brings sustainability to Caguas. 相似文献
914.
Hoopfest: Using longitudinal economic impact data to assess the success of a strategic reorientation
The authors report the economic impact of a strategy change for a nonprofit sport association, Hoopfest, over an eight year period. Hoopfest organizes the largest annual 3-on-3 basketball tournament in the world. The study employs an economic impact methodology because the local community expressed a concern with related economic development issues. An initial assessment indicated the two-day tournament had an overall economic impact on the region of about seventeen million dollars. Twenty-two thousand people competed in the tournament and at least another one hundred thousand people watched the event. Hoopfest officials were challenged by a simple question: how could they enhance the economic benefits of this basketball tournament? 相似文献
915.
916.
Little research has investigated the observational learning process from a developmental perspective. The purpose of this study was to extend previous research by considering two factors: performance versus learning and sequencing versus form scores. Children (N = 60) comprising two age groups (5-0 to 6-11 and 8-0 to 9-11 years) were randomly assigned to verbal rehearsal only, model only, or model plus verbal rehearsal conditions. The task was a 6-part motor skill sequence in which proper sequencing and quality of form were assessed. A 2 x 3 x 4 (age group by model type by trial blocks) repeated measures MANOVA revealed a significant three-way interaction. Older children performed equally well under any of the model type conditions during both performance and learning. For younger children, a model plus rehearsal was superior to rehearsal only on sequence and form at performance and learning and superior to model only on sequence scores during the first two performance trial blocks. Model only and model plus rehearsal conditions were equally effective on form scores. These results suggest that age differences exist in the modeling of motor skills under conditions varying in model type, sequence and form scores, and performance and learning phases. 相似文献
917.
918.
919.
State-of-the-art of modeling complex information systems is briefly discussed. A distinction is made between macrolevel and microlevel modeling of such systems. Modeling approaches and techniques, appropriate for each of these two levels are described and assessed. 相似文献
920.
Yu. V. Babushkina 《Scientific and Technical Information Processing》2007,34(2):106-109
The possibility of using an enterprise’s website to implement its communication policy is considered. The classification of websites is presented and the interconnection of objectives for constructing an electronic representation and its information content is described. The role of an enterprise’s information service employees in the construction, support, and promotion of the enterprise’s website is defined. 相似文献