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排序方式: 共有590条查询结果,搜索用时 10 毫秒
71.
H Kubota H Tabara T Kotoh DD Kumar N Monden R Watanabe H Kohno N Nagasue 《Canadian Metallurgical Quarterly》1998,80(2):304-308
Metallothionein (MT) mRNA levels were analyzed following exposure of neonatal rat primary astrocyte cultures to physiologic pH (7.4), acidosis (pH 6.5 and 6.0), and dimethyl sulfoxide (DMSO). Treatments were carried out both in the presence and absence of the bioflavonoid, quercetin. Total RNA was probed on northern blots with [alpha32P]dCTP-labeled synthetic cDNA probes specific for rat MT isoform mRNAs. MT-I and MT-II mRNA levels in astrocytes exposed to pH 6.5 or pH 6.0 were increased compared to controls (pH 7.4). Treatment with DMSO in the presence and absence of acidosis, also increased MT-I and MT-II mRNA levels compared to controls (pH 7.4). The DMSO-induced increase in MT mRNA expression was reversed by treatment of astrocytes with quercetin, such that MT-I and MT-II mRNA levels in DMSO plus quercetin-treated astrocytes were indistinguishable from mRNA levels in their respective controls at pH 7.4, pH 6.5, and pH 6.0. These findings suggest that both acidosis and DMSO exposure are associated with increased astrocytic MT synthesis at the mRNA level, and that quercetin, effectively blocks MT mRNA induction by DMSO. 相似文献
72.
Akemi K. Horigane Masami Kawabuchi Satoshi Uchijima Mitsuru Yoshida 《Food research international (Ottawa, Ont.)》2009,42(1):41-50
The effect of seasonings on the texture of cooked spaghetti was examined by sensory and shearing tests. Spaghetti tossed with sucrose, trehalose, salt, and monosodium glutamate and their mixture retarded deterioration of the firmness of spaghetti strands. To investigate the penetration of water and seasonings, maps of spin–spin relaxation time and their profiles from the center to the surface of a spaghetti strand were acquired by magnetic resonance imaging. The homogenization of moisture distribution in cooked spaghetti during holding was delayed temporarily by salt owing to a back current caused by the gradient of salt content on the surface immediately after tossing. Monosodium glutamate rapidly penetrated into spaghetti strands and caused water T2 decrease possibly owing to the decreased mobility of water molecules in starch gel, whereas the sweeteners hardly altered the T2 maps. Salt and monosodium glutamate are considered to retard more effectively the deterioration of firmness of spaghetti. 相似文献
73.
The mode of degradation of long chain keto acids by two microorganisms was investigated.Escherichia coli K-12 converted 12-ketooctadecanoic acid to 4-ketodecanoic acid, accumulating some amounts of intermediates, 10-ketohexadecanoic,
8-ketotetradecanoic and 6-ketododecanoic acids. In contrast,Candida tropicalis completely metabolized the keto acid with transient accumulation of the metabolites mentioned above. The difference between
the metabolism byE. coli of hydroxy acid and keto acid is that 12-hydroxyoctadecanoic acid is degraded as far as 6-hydroxydodecanoic acid, while 12-ketooctadecanoic
acid can be degraded as far as 4-ketodecanoic acid. 相似文献
74.
Shinichi Tamura Kokichi Tanaka Seiji Ohmori Kozo Okazaki Akira Okada Mitsuru Hoshi 《Pattern recognition》1983,16(2):149-162
An algorithm for measuring an index of leakage in fluorescein fundus angiography is presented. The number of pixels whose gray level exceeds an automatically determined slice level is calculated. An automatic blood vessel elimination technique is introduced. Further, a method of measuring the short term change of leakage from a time series of the fluorescein fundus angiographs is described. Our system can also deal with the time series images obtained on different occasions (long term change).The features of this paper are: (1) this paper deals with double time sequence images (short and long term); (2) an automatic blood vessel recognition algorithm is employed. 相似文献
75.
76.
The vaporization of Li4TiO4 has been studied by a mass spectrometric Knudsen effusion method in the temperature range 1082–1582 K. Identified vapors are Li(g), LiO(g), Li2O(g) and Li3O(g). When the vaporization proceeds, the content of Li2O in the Li4TiO4 sample decreases and the condensed phase of the sample changes to β-Li4TiO4 plus l-Li2TiO3 below 1323 K, to β-Li4TiO4 plus h-Li2TiO3 in the range 1323–1473 K and to h-Li2TiO3 plus liquid above 1473 K. On the basis of the partial pressure data, the enthalpies of formation for β-Li4TiO4 from elements and from constituent oxides have been determined to be ΔHf,298°(β-Li4TiO4,s) = −2247.8 ± 14.3 kJ mol−1 and Δfox,298°(β-Li4TiO4, s) = −107.3 ± 14.3 kJ mol−1, respectively. 相似文献
77.
78.
Mitsuru Sekioka 《Remote sensing of environment》1985,18(2):193-203
Detailed infrared images are useful for investigating thermal features of geothermal fields. A remote sensing system which is installed on low-altitude-flying helicopters is developed to get the infrared images with high resolution. But those images can cover only a limited domain. As the system can fit visible images on infrared ones simultaneously obtained, within a common field of view, this makes it possible to determine the positions of target areas by finding out geographical and topographical features over the visible images in spite of its limited areas. Observations by means of the helicopter-borne system are described for the two geothermal fields in Japan. Finally, heat discharge from those fields are estimated by analyzing the observed thermal images. 相似文献
79.
High-performance genetic analysis on microfabricated capillary array electrophoresis plastic chips fabricated by injection molding 总被引:1,自引:0,他引:1
Dang F Tabata O Kurokawa M Ewis AA Zhang L Yamaoka Y Shinohara S Shinohara Y Ishikawa M Baba Y 《Analytical chemistry》2005,77(7):2140-2146
We have developed a novel technique for mass production of microfabricated capillary array electrophoresis (mu-CAE) plastic chips for high-speed, high-throughput genetic analysis. The mu-CAE chips, containing 10 individual separation channels of 50-microm width, 50-microm depth, and a 100-microm lane-to-lane spacing at the detection region and a sacrificial channel network, were fabricated on a poly(methyl methacrylate) substrate by injection molding and then bonded manually using a pressure-sensitive sealing tape within several seconds at room temperature. The conditions for injection molding and bonding were carefully characterized to yield mu-CAE chips with well-defined channel and injection structures. A CCD camera equipped with an image intensifier was used to monitor simultaneously the separation in a 10-channel array with laser-induced fluorescence detection. High-performance electrophoretic separations of phiX174 HaeIII DNA restriction fragments and PCR products related to the human beta-globin gene and SP-B gene (the surfactant protein B) have been demonstrated on mu-CAE plastic chips using a methylcellulose sieving matrix in individual channels. The current work demonstrated greatly simplified the fabrication process as well as a detection scheme for mu-CAE chips and will bring the low-cost mass production and application of mu-CAE plastic chips for genetic analysis. 相似文献
80.
Bakalova R Zhelev Z Jose R Nagase T Ohba H Ishikawa M Baba Y 《Journal of nanoscience and nanotechnology》2005,5(6):887-894
The present study describes an enhancement of the photoluminescence of CdSe quantum dots under long-term ultraviolet irradiation in organic solvents. The photoenhancement effect followed multiexponential kinetics and was found to depend on several factors: intensity of ultraviolet light, polarity of the solvent, presence of capping agents on the nanocrystal surface, and presence of free Cd and Se ions in the solution. High intensity ultraviolet irradiation provoked a rapid enhancement of the photoluminescence of CdSe nanocrystals, reaching the maximum with subsequent photoluminescence decay. Low-intensity ultraviolet irradiation provoked a comparatively slow enhancement of the photoluminescence of CdSe nanocrystals, reaching saturation after 5-6 hours of irradiation in organic solvents (butanol and chloroform). The photoenhancement effect was reversible or irreversible depending on the additional ingredients. The role of free Cd and Se in these processes was clarified. The results are discussed in the context of ultraviolet induced liberation of free Cd and Se ions from the nanocrystal surface and their hypothetical reversible deposition with trapping of the surface holes and influencing the efficiency of radiative versus nonradiative exciton decay during the enhancement of photoluminescence. 相似文献