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排序方式: 共有137条查询结果,搜索用时 31 毫秒
81.
Catalysis Letters - Two tungstates containing platinum nanoparticles (Pt Npts) were obtained by air-calcining α-Keggin-type diplatinum(II)-coordinated polyoxotungstates,... 相似文献
82.
Two amylases of an alkalopsychrotrophic Micrococcus were purified by chromatographies of DEAE-Toyopearl, Butyl-Toyopearl and Shodex WS-2003. Molecular weights and pI values of the purified enzymes, I and II, were 185000 and 125000 by SDS-PAGE and 4.8 and 4.3 by isoelectric focusing, respectively. Enzyme I had not only amylase but also pullulanase activity. In the presence of Ca2+ ions, other properties of both enzymes were very similar: optimum temperature 55–60°C, optimum pH 7.5–8.0 km value for maltopentaose 0.09 mM. Both amylases were completely inactivated after incubation with EDTA at 30°C and thereafter, could be reactivated by an addition of CaCl2. In the absence of Ca2+ ions, amylase I became thermoresistant, while the thermostability of amylase II decreased. Neither amylase activity of enzyme I nor enzyme II was inhibited by pullulan. 相似文献
83.
84.
Junko Okuda-Shimazaki Saiko Takaku Koki Kanehira Shunji Sonezaki Akiyohshi Taniguchi 《International journal of molecular sciences》2010,11(6):2383-2392
Titanium dioxide (titania) nanoparticle aggregation is an important factor in understanding cytotoxicity. However, the effect of the aggregate size of nanoparticles on cells is unclear. We prepared two sizes of titania aggregate particles and investigated their biological activity by analyzing biomarker expression based on mRNA expression analysis. The aggregate particle sizes of small and large aggregated titania were 166 nm (PDI = 0.291) and 596 nm (PDI = 0.417), respectively. These two size groups were separated by centrifugation from the same initial nanoparticle sample. We analyzed the gene expression of biomarkers focused on stress, inflammation, and cytotoxicity. Large titania aggregates show a larger effect on cell viability and gene expression when compared with the small aggregates. This suggests that particle aggregate size is related to cellular effects. 相似文献
85.
Urita K Seki S Utsumi S Noguchi D Kanoh H Tanaka H Hattori Y Ochiai Y Aoki N Yudasaka M Iijima S Kaneko K 《Nano letters》2006,6(7):1325-1328
We present significant electrical conductivity responses of the pelletized as-prepared and oxidized (ox-) single-wall carbon nanohorns (SWNHs) on adsorption of CO(2) and O(2). The morphological and pore structures of both pelletized SWNHs were examined by transmission electron microscopy (TEM) and nitrogen adsorption isotherm, leading to explicit evidences of the formation of nanoscale windows on the wall by oxidation. The SWNH and ox-SWNH induced a semiconducting behavior, strongly responded to CO(2) and O(2) adsorptions, and each exhibited n-type- and p-type-like conductivities. The electrical conductivity increase and decrease for CO(2) and O(2) adsorption, respectively, were observed for SWNH, whereas ox-SWNH showed a marked electrical conductivity drop on CO(2) adsorption and almost no change on O(2) adsorption. The dramatically different electrical conductivity response of ox-SWNH is presumed to be ascribed to the annihilation of pentagons in the single graphene wall by oxidation. 相似文献
86.
87.
Tiago Novaes Pinheiro Milena Gomes Melo Leite Cristiane Cantiga da Silva Cleber Nunes Alexandre Lioney Nobre Cabral Hannah Marcelle Paulain Carvalho Daniel Frota de Souza Jéssica Lourdes de Aguiar Gonçalves Thales Edecherly Nasserala de Souza Nara Deise de Souza Melo Luciano Tavares Ângelo Cintra Beatriz Terumi Barreto Kanehira Gustavo Cavalcanti de Albuquerque 《Microscopy research and technique》2022,85(4):1421-1432
The current research aims to perform a comparative evaluation of vegetable matter involved lesions with oral parasitic infections found in oral mucosa, presenting histochemical methods to differentiate their microscopic similarities. Eight cases were selected out of a sample of 1.975 reports from a single Oral and Maxillofacial Pathology Service of the author's institution from 2012 to 2019. Specimens were examined by hematoxylin and eosin staining (HE), periodic acid-Schiff (PAS) staining, Gomori–Grocott staining, Ziehl–Neelsen staining, Giemsa, and mucicarmine staining. Microscopic analysis included fluorescence, polarized light, and confocal microscopy. Microscopically, in HE coloration, hookworm eggs showed as eosinophilic. Inflammatory multinucleated giant cells and lymphocytes, were usually related to the nematode eggs, forming an intense inflammatory infiltrate. Biofluorescent properties of eggs and larvae revealed to be sensitive in the detection of parasitic structures contrasting with the inflamed connective tissue. Vegetable presence was confirmed by polarized light microscopy and it was found to be associated with microbial biofilms. Confocal microscopy has showed to be an excellent method for morphotype differentiation of parasitic eggs. Parasitic infection and vegetable matter displayed similarities in the inflammatory response, but the latter can rot and agglomerate biofilms. The microscopic diagnosis of such infections requires the interpretation of challenging morphological features since the parasites are usually sectioned and mixed with an inflammatory reaction. These histochemical approaches proved to be excellent to distinguish both lesions. 相似文献
88.
The expression and activity of antioxidant enzymes in the liver of rats exposed to high‐fructose diet in the period from weaning to adulthood
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89.
Usami R Fukushima T Mizuki T Yoshida Y Inoue A Horikoshi K 《Journal of Bioscience and Bioengineering》2005,99(2):169-174
Strains of halophilic archaea, Haloarcula vallismortis and two Haloarcula strains OHF-1 and OHF-2, showed high tolerance to organic solvents at high media NaCl concentrations. For example, the lowest log Pow of the solvent which allowed growth (log Pow is the common logarithm of the partition coefficient of a given solvent in a mixture of n-octanol and water) for H. vallismortis was 5.1 at 20% NaCl and 4.4 at 30% NaCl. The solvent tolerance of Haloarcula argentinensis, on the other hand, was not affected by the NaCl concentration. Cells of strains OHF-1 and OHF-2 were of triangular or irregular morphology but became spherical in cultures in NaCl media overlaid with cyclohexane (log Pow=3.4), but returned to the triangular shape when the organic solvent evaporated from the medium. When cells of strains OHF-1, OHF-2, and H. argentinensis were grown in NaCl media in the presence of n-decane, they contained less phosphatidylglycerol and more phosphatidylglycerosulfate and phosphatidylglycerophosphate methyl ester than when grown without added n-decane. When the solvent was removed from the media after cultivation, the levels of these compounds returned to their initial ones. 相似文献
90.
Shingo Kanehira Soshu Kirihara Yoshinari Miyamoto Kazuaki Sakoda Mitsuo Wada Takeda 《Journal of the American Ceramic Society》2005,88(9):2480-2484
Three-dimensional photonic crystals with a diamond lattice structure consisting of 5 × 5 × 5 unit cells with the unit cell dimension of 15 mm were fabricated using TiO2 -based ceramic particles dispersed epoxy by stereolithography. The diamond lattice showed a perfect band gap between 14.3 and 15.8 GHz. An air cavity defect with a rectangular shape (15 mm × 45 mm × 15 mm) was introduced at the center of the crystal by extracting 3 unit cells in order to investigate the shape effect of the defect on the formation of localized defect modes of electromagnetic wave. When microwaves were radiated normal to the wide sides (45 mm × 15 mm) of the rectangular shape defect, a sharp localized mode appeared at the middle of the band gap. However, no localized mode was observed for incident waves normal to the smaller side (15 mm × 15 mm) because of the symmetry mismatching between internal eigenmodes in the defect cavity and incident plane waves. The mode analysis using a simple cavity model showed the penetration of the electric field of resonant modes about 2.4 mm into the host lattice. 相似文献