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排序方式: 共有1268条查询结果,搜索用时 31 毫秒
131.
Masato Tazawa Masahisa Okada Kazuki Yoshimura Shunjiro Ikezawa 《Solar Energy Materials & Solar Cells》2004,84(1-4):159
Some of the heat mirrors, which have high transmittance in the visible region and high reflectance in the infrared, consist of three thin titanium compound stacked films, TiO2/TiN/TiO2 on glass substrate. TiO2 is known to have excellent photo-catalytic properties and the top layer may be expected to work as a photo-catalyst as well as the anti-reflection coating. However, strong thickness dependence of the photo-catalytic properties has been reported and the optimum thickness of the top layer for the heat mirror was too thin for the photo-catalytic properties for decomposition of acetaldehyde gas. In this report, we show a possibility to realize a multi-functional heat mirror which shows the photo-catalytic and heat mirror effects simultaneously by optical calculation and preliminary experiments. We found top TiO2 thickness of 350–400 nm or about 1170 nm showed high heat mirror performance. This thickness was enough to show the photo-catalytic properties. 相似文献
132.
K. Yoshimura 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1910,19(5):253-256
Ohne ZusammenfassungMitteilung aus dem Chemischen Laboratorium der Landwirtschaftlichen Hochschule zu Morioka (Japan) 相似文献
133.
134.
K Kugiyama M Ohgushi T Motoyama O Hirashima H Soejima K Misumi M Yoshimura H Ogawa S Sugiyama H Yasue 《Canadian Metallurgical Quarterly》1998,97(23):2299-2301
BACKGROUND: Oxygen free radicals have been shown to cause endothelial vasomotor dysfunction. This study examined the effect of reduced glutathione (GSH), an antioxidant, on human coronary circulation. METHODS AND RESULTS: Responses of epicardial diameter and blood flow of the left anterior descending coronary artery to intracoronary infusion of acetylcholine (ACh, 50 microg/min) were measured by quantitative coronary angiography and Doppler flow-wire technique, respectively, before and during combined intracoronary infusion of GSH (50 mg/min) or saline in 26 subjects with no significant coronary stenosis. GSH infusion suppressed the constrictor response of epicardial diameter to ACh and enhanced the increase in blood flow response to ACh. Furthermore, GSH potentiated the coronary dilator effect of nitroglycerin. A beneficial effect of GSH on the epicardial diameter response to ACh was observed in a subgroup of subjects with > or = 1 coronary risk factors but not in a subgroup without risk factors. Saline infusion did not have any effects. CONCLUSIONS: The results indicate that GSH improved coronary endothelial vasomotor function, particularly in subjects with coronary risk factors, and it potentiated the vasodilator effect of nitroglycerin in human coronary arteries. 相似文献
135.
The translocation of soluble Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) to postsynaptic densities (PSDs) was investigated. When soluble CaM kinase II previously autophosphorylated was incubated with PSDs, the kinase was precipitated by centrifugation, indicating that the soluble kinase associated with PSDs and formed a PSD-CaM kinase II complex. Ca2+-independent activity generated by autophosphorylation of the kinase was retained in the complex. A number of PSD proteins were phosphorylated by the kinase associated with PSDs in both the absence and presence of Ca2+. When PSD-CaM kinase II complex was incubated at 30 degrees C, the enzyme was dephosphorylated and released from the complex. These results indicate that CaM kinase II reversibly translocates to PSDs in a phosphorylation-dependent manner. 相似文献
136.
D Watanabe R Yoshimura M Khalil K Yoshida T Kishimoto T Taga H Kiyama 《Canadian Metallurgical Quarterly》1996,8(8):1630-1640
The localization of gp130, the signal transducing receptor component used in common for interleukin (IL)-6, IL-11, ciliary neurotrophic factor (CNTF), LIF and OSM, in the rat brain was demonstrated by immunohistochemistry using an antibody specific to gp130. The gp130 immunoreactivity was observed in both glial and neuronal cells. Two distinct neuronal staining patterns were observed. The first showed neuropil staining, observed mainly in telencephalic structures including the hippocampus, cerebral cortex and caudate-putamen. The second pattern was observed on the cytoplasmic membrane of neuronal somata and was found primarily in the lower brainstem, in the large neurons of the reticular formation, and in spinal and cranial motor neurons. Electron-microscopic analysis revealed that both types of gp130 immunoreactivity were primarily associated with the cytoplasmic membrane and were not localized exactly at synaptic sites. Further, gp130 immunoreactivity was also observed in the oligodendrocytes and subependymal zone. These widespread but characteristic patterns of gp130 immunoreactivity overlap well with those of IL-6 receptor and CNTF alpha chains, suggesting a role of cytokines and growth factors such as IL-6 and CNTF via gp130 in certain specific regions of the brain. 相似文献
137.
M Yoshimura T Oshima H Matsuura T Inoue M Kambe G Kajiyama 《Canadian Metallurgical Quarterly》1997,17(11):3356-3361
Receptor-mediated and capacitative Ca2+ entry are the primary Ca2+ entry pathways in endothelial cells (ECs). The mechanisms for Ca2+ entry via these pathways have not been fully elucidated. In this study, the effect of low and high external Mg2+ concentrations on these Ca2+ entry pathways was examined in human coronary arterial ECs. External Mg2+ concentration did not affect cytosolic free Mg2+ concentration. After exposure to thrombin in Ca(2+)-free medium, addition of Ca2+ to the medium caused a rise in cytosolic free Ca2+ concentration ([Ca2+]i), indicating thrombin-induced Ca2+ influx. Thrombin-induced Ca2+ influx was inhibited by not only low but also high external Mg2+ concentrations. After depletion of endoplasmic Ca2+ stores by thapsigargin, addition of Ca2+ to the medium induced an increase in [Ca2+]i, indicating capacitative Ca2+ entry. Capacitative entry was found to be accelerated by low external Mg2+ and inhibited by high external Mg2+ concentration. Results suggest that receptor-mediated Ca2+ influx requires external Mg2+ but is inhibited by increased external Mg2+ concentrations and that capacitative Ca2+ entry is reduced by external Mg2+ in human coronary arterial ECs. 相似文献
138.
K Nakao M Ohgushi M Yoshimura K Morooka K Okumura H Ogawa K Kugiyama Y Oike K Fujimoto H Yasue 《Canadian Metallurgical Quarterly》1997,80(5):545-549
Xanthomas may be associated with benign or malignant lymphoproliferative diseases, often with associated hypergammaglobulinema. In human immunodeficiency virus type 1 (HIV-1) disease, there is a high lymphoproliferative rate despite the immunodeficiency and increased cell death. We report three HIV-1-positive patients with facial papular xanthomatosis eruptions associated with hypergammaglobulinema, and an immunoglobulin A (IgA) gammopathy. Histopathologic features include lipid-laden macrophages, extracellular nuclear dust with phagocytosized nuclear debris, and hyalinization with areas of hyaline necrosis of collagen fibers. These distinctive papular xanthomas may be a marker of HIV-1 disease and of a pattern of immunodysregulation, immunodeficiency, and lymphoid proliferation seen in HIV-1 disease. 相似文献
139.
H Tohgi K Utsugisawa M Yoshimura M Yamagata Y Nagane K Saitoh 《Canadian Metallurgical Quarterly》1997,768(1-2):86-90
140.
It is well known that silica exposure leads in an experimental model to the development of an acute fibrotic process. In human beings two main observations have already been done: (1) silica exposure is frequently associated with the development of connective tissue disease (CTD), especially progressive systemic sclerosis; (2) 10 to 20% patients with CTD developed pulmonary fibrosis. In this context we report 26 cases of coal miners who presented with clinical, radiological, biological and functional characteristics mimicking idiopathic pulmonary fibrosis (IPF), with or without associated coal worker's pneumoconiosis (CWP). All were men; mean age was 68 +/- 9.2 years. Twenty-three were smokers. Duration of exposure was 28.8 +/- 9.1 years. All the patients had dyspnea (stage III, IV in the NHYA classification) and diffuse crackles. Eleven out of 26 had finger clubbing. Computed tomography showed honeycombing (23 cases), and/or ground glass opacities (6 cases) with bronchiectasis (3 cases) predominant in the lower lobes; 19 had radiological signs of CWP, micronodules (n = 16) and nodules (n = 3) predominant in the upper lobes. BAL exhibited an increased % of neutrophils (11.9 +/- 16.1%). Lung function demonstrated a restrictive pattern (TLC = 73 +/- 15.6% and VC = 80 +/- 18% of predicted values) associated with a decreased DLCO (51.8 +/- 23.6% of predicted values) and hypoxemia (at rest = 66.5 +/- 11.2 mmHg, upon effort = 56 +/- 12 mmHg). Lung biopsies were performed in four cases and demonstrated interstitial fibrosis of intraalveolar septum with an accumulation of immune and inflammatory cells similar to the one described in IPF. The association between IPF and silica exposure with or without associated CWP points out the problem of legal recognition of idiopathic-like pulmonary fibrosis as a complication of the occupational exposure of coal workers. 相似文献