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排序方式: 共有438条查询结果,搜索用时 31 毫秒
81.
Suvarin Pavasutthipaisit Melanie Stoff Tim Ebbecke Malgorzata Ciurkiewicz Sabine Mayer-Lambertz Theresa Strk Kevin D. Pavelko Bernd Lepenies Andreas Beineke 《International journal of molecular sciences》2021,22(13)
Neurotropic viruses target the brain and contribute to neurologic diseases. Caspase recruitment domain containing family member 9 (CARD9) controls protective immunity in a variety of infectious disorders. To investigate the effect of CARD9 in neurotropic virus infection, CARD9−/− and corresponding C57BL/6 wild-type control mice were infected with Theiler’s murine encephalomyelitis virus (TMEV). Brain tissue was analyzed by histology, immunohistochemistry and molecular analyses, and spleens by flow cytometry. To determine the impact of CARD9 deficiency on T cell responses in vitro, antigen presentation assays were utilized. Genetic ablation of CARD9 enhanced early pro-inflammatory cytokine responses and accelerated infiltration of T and B cells in the brain, together with a transient increase in TMEV-infected cells in the hippocampus. CARD9−/− mice showed an increased loss of neuronal nuclear protein+ mature neurons and doublecortin+ neuronal precursor cells and an increase in β-amyloid precursor protein+ damaged axons in the hippocampus. No effect of CARD9 deficiency was found on the initiation of CD8+ T cell responses by flow cytometry and co-culture experiments using virus-exposed dendritic cells or microglia-enriched glial cell mixtures, respectively. The present study indicates that CARD9 is dispensable for the initiation of early antiviral responses and TMEV elimination but may contribute to the modulation of neuroinflammation, thereby reducing hippocampal injury following neurotropic virus infection. 相似文献
82.
Yuan Zhao Theresa E. Feltes John R. Regalbuto Randall J. Meyer Robert F. Klie 《Catalysis Letters》2011,141(5):641-648
Abstract
The conversion of synthesis gas to hydrocarbon fuels by Co catalysts through the Fischer–Tropsch process has received renewed attention particularly with regard to the role of promoters. In this letter, we utilize scanning transmission electron microscopy imaging and electron energy-loss spectroscopy to elucidate the interaction between the Mn promoter, the Co nano-catalysts, and the TiO2 support. In-situ heating experiments show the diffusion of Mn and Ti-support onto the Co particle under reducing conditions. 相似文献83.
84.
The synthesis, characterization, and application as polymers and anti-wear additives of nanosized zinc oxide particles obtained by conventional and supercritical ethanol drying are reported in this study. The nanaoparticles of ZnO produced by the two different drying techniques were characterized using Fourier Transform Infrared (FT-IR) spectrophotometry, Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Thermogravimetric analysis (TGA) to elucidate the shape, size, composition, and stability of the nanoparticles. ZnO nanoparticles were then applied to poly (vinyl chloride) (PVC) powder and light mineral oil to assess their effectiveness and suitability as additives in diverse areas. XRD analysis revealed ZnO crystalline structure with average particle size of 24.7 nm for zinc oxide nanoparticles prepared by supercritical ethanol drying while SEM showed well-isolated and monodisperse particles with average size of 61.08 nm. 相似文献
85.
Oscar B. Zamora Lucille Elna P. de Guzman Sue Liza C. Saguiguit Ma. Theresa M. Talavera Normahitta P. Gordoncillo 《Food Security》2013,5(6):873-886
The typical Filipino diet mainly consists of rice, fish and vegetables, with rice being the greatest source of calories. The consumption of a maize, starchy roots and tubers as rice substitutes or supplements, and vegetables and fruits has generally declined, while the consumption of fats, oils and meats has increased. Stunting is the most prevalent form of malnutrition among Filipinos. Vitamin A Deficiency, Iodine Deficiency Disorder, and Iron Deficiency Anemia remain public health problems for children and pregnant and lactating women. The link between nutrition and agriculture in the Philippines has focused on leveraging agriculture to improve nutrition. The programs that had been initiated by the government, NGO/CSO or private sector were conceptualized and implemented before the elements of a nutrition-sensitive agriculture framework were identified. These programs were implemented to address food production and the nutritional needs of individuals, families, and communities only with reference to nutrition security. Many of these programs have been successful as they implemented best practices that could be applied to forge a superior approach that optimizes the agriculture-nutrition nexus. This study identified these best practices or elements of success. The elements that have been noted as reasons for the success of some of these programs are: presence of strong political will and enabling policy environment; forging of new forms of partnerships, strategic collaboration, sound coordination and structures; exploiting the best that science and technology could offer; democratizing community participation; strong capacity building component and access to reliable technical expertise; knowledge and sensitivity to local cultures, beliefs and practices; professionalized promotion and ‘messaging’; use of catchy terms for easy recall; availability of sustainable funding; use of the life cycle approach in nutrition; holistic community nutrition perspective; practice and promotion of biodiversity-based agricultural production system; and control of the means of production. 相似文献
86.
During summer, female meadow voles (Microtus pennsylvanicus) maintain territories and males do not engage in paternal care. As day length shortens, territories dissolve and males nest with females and young. Because paternal behavior has never been studied in free-living meadow voles during colder months or in the laboratory under short photoperiods, the authors examined whether males housed in short day (SD) lengths exhibited more frequent or better quality paternal behavior than males housed in long day (LD) lengths. Sexually and parentally inexperienced (naive) SD males exhibited proportionally more and qualitatively better paternal care than naive LD males. SD males were more responsive than LD males to classic social cues associated with preparturn aggression inhibition and paternal onset. SD sires also displayed qualitatively better paternal behavior than LD sires. These data suggest that meadow vole paternal state is regulated by specific social and environmental cues that may contain reliable information about ecological conditions that favor paternal care. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
Phase relations within the "V2 O3 –FeO" and V2 O3 –TiO2 oxide systems were determined using the quench technique. Experimental conditions were as follows: partial oxygen pressures of 3.02 × 10−10 , 2.99 × 10−9 , and 2.31 × 10−8 atm at 1400°, 1500°, and 1600°C, respectively. Analysis techniques that were used to determine the phase relations within the reacted samples included X-ray diffractometry, electron probe microanalysis (energy-dispersive spectroscopy and wavelength-dispersive spectroscopy), and optical microscopy. The solid-solution phases M2 O3 , M3 O5 , and higher Magneli phases (M n O2 n −1 , where M = V, Ti) were identified in the V2 O3 –TiO2 system. In the "V2 O3 –FeO" system, the solid-solution phases M2 O3 and M3 O4 (where M = V, Ti), as well as liquid, were identified. 相似文献
88.
Mendenhall Amy N.; Fristad Mary A.; Early Theresa J. 《Canadian Metallurgical Quarterly》2009,77(3):463
This study investigated the impact of psychoeducation on service utilization and mood symptom severity in children with mood disorders. Parents’ knowledge of mood disorders, beliefs about treatment, and perceptions of children’s need for treatment were hypothesized to mediate the relationship between psychoeducation and service utilization and between psychoeducation and mood symptom severity. Linear mixed effects modeling and joint significance test for mediation were used in secondary data analyses of the multifamily psychoeducation group (MFPG) study, a randomized controlled trial of 165 children ages 8 to 12 years with mood disorders. A majority of those sampled were male (73%) and White, non-Hispanic (90%), and the median range of family income was $40,000–$59,000. Participation in MFPG significantly improved quality of services utilized, mediated by parents’ beliefs about treatment. Participation in MFPG also significantly improved severity of child’s mood symptoms, mediated by quality of services utilized. MFPG appears to be a psychoeducational intervention that helps parents to become better consumers of the mental health system who access higher quality services. Children’s symptom severity decreases as a result. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
Abdulreza Tabe‐Mohammadi Juan P. Garcia Villaluenga Hyo J. Kim Theresa Chan Vanessa Rauw 《应用聚合物科学杂志》2001,82(12):2882-2895
The performances of cellulose acetate membranes prepared with casting solutions, with acetone, dimethylformamide (DMF), and N‐methylpyrrolidone (NMP) as solvents, were studied in a series of methanol/methyl tertiary butyl ether separation experiments. The flux and selectivity of the membrane samples were affected by the type of solvent used to prepare the casting solution. The sample with DMF consistently gave the highest selectivity and lowest flux, followed by the samples with NMP and acetone. The differences in the performances were attributed to the effects of the volatility and evaporation rates of the solvents. Scanning electron microscopy and atomic force microscopy techniques were used for comparing the morphologies of the membranes. In addition, we used Raman spectroscopy as a novel technique to study the sorption selectivities of the membrane samples prepared with the three different solvents. In a parallel study, the relation between the polymer concentration in the casting solution and the morphology and performance of the membrane samples was studied. Under similar preparation conditions, the morphology of the membrane changed from being porous to being dense when the membrane was prepared with casting solutions with increasing polymer concentration. Also, the selectivity increased and the permeability decreased with increasing polymer concentration in the casting solution. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2882–2895, 2001 相似文献
90.
Jonas Baumann Christian Krnig Theresa Staufer Christopher Schlesiger Oliver Schmutzler Florian Grüner Wolfgang Malzer Birgit Kanngießer 《International journal of molecular sciences》2022,23(9)
Trace elements, functionalized nanoparticles and labeled entities can be localized with sub-mm spatial resolution by X-ray fluorescence imaging (XFI). Here, small animals are raster scanned with a pencil-like synchrotron beam of high energy and low divergence and the X-ray fluorescence is recorded with an energy-dispersive detector. The ability to first perform coarse scans to identify regions of interest, followed by a close-up with a sub-mm X-ray beam is desirable, because overall measurement time and X-ray dose absorbed by the (biological) specimen can thus be minimized. However, the size of X-ray beams at synchrotron beamlines is usually strongly dependent on the actual beamline setup and can only be adapted within specific pre-defined limits. Especially, large synchrotron beams are non-trivial to generate. Here, we present the concept of graphite-based, convex reflection optics for the one-dimensional enlargement of a 1 mm wide synchrotron beam by a factor of 5 to 10 within a 1 m distance. Four different optics are tested and characterized and their reflection properties compared to ray tracing simulations. The general shape and size of the measured reflection profiles agree with expectations. Enhancements with respect to homogeneity and efficiency can be expected with improved optics manufacturing. A mouse phantom is used for a proof-of-principle XFI experiment demonstrating the applicability of coarse and fine scans with the suggested optics design. 相似文献