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1.
The brain undergoes ionizing radiation exposure in many clinical situations, particularly during radiotherapy for brain tumors. The critical role of the hippocampus in the pathogenesis of radiation-induced neurocognitive dysfunction is well recognized. The goal of this study is to test the potential contribution of non-targeted effects in the detrimental response of the hippocampus to irradiation and to elucidate the mechanisms involved. C57Bl/6 mice were whole body (WBI) or partial body (PBI) irradiated with 0.1 or 2.0 Gy of X-rays or sham irradiated. PBI consisted of the exposure of the lower third of the mouse body, whilst the upper two thirds were shielded. Hippocampi were collected 15 days or 6 months post-irradiation and a multi-omics approach was adopted to assess the molecular changes in non-coding RNAs, proteins and metabolic levels, as well as histological changes in the rate of hippocampal neurogenesis. Notably, at 2.0 Gy the pattern of early molecular and histopathological changes induced in the hippocampus at 15 days following PBI were similar in quality and quantity to the effects induced by WBI, thus providing a proof of principle of the existence of out-of-target radiation response in the hippocampus of conventional mice. We detected major alterations in DAG/IP3 and TGF-β signaling pathways as well as in the expression of proteins involved in the regulation of long-term neuronal synaptic plasticity and synapse organization, coupled with defects in neural stem cells self-renewal in the hippocampal dentate gyrus. However, compared to the persistence of the WBI effects, most of the PBI effects were only transient and tended to decrease at 6 months post-irradiation, indicating important mechanistic difference. On the contrary, at low dose we identified a progressive accumulation of molecular defects that tended to manifest at later post-irradiation times. These data, indicating that both targeted and non-targeted radiation effects might contribute to the pathogenesis of hippocampal radiation-damage, have general implications for human health.  相似文献   
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BACKGROUND: Human natural xenoantibodies represent a major hurdle to the clinical application of pig lungs in transplantation by initiating hyperacute rejection within minutes to hours. OBJECTIVE: The object was to compare pig organ perfusion and specific depletion of anti-alpha-galactosyl xenoantibodies for prevention of hyperacute rejection in the pig to human lung combination. METHODS: Large White pig (20-25 kg) left lungs were removed and continuously ventilated and reperfused ex vivo either with (1) whole human blood previously perfused in situ through pig right lung (group I), liver (group II), or spleen (group III) or with (2) human plasma in vitro immunoabsorbed on columns containing alpha-galactosyl disaccharide (Gal-alpha-(1-3)Gal-beta-(CH2)3NH2; B disaccharide) (group IV). Each study group included 6 animals. RESULTS: The in situ and in vitro preperfusions depleted anti-alpha-galactosyl xenoantibodies and all in situ perfused pig organs showed histologic signs of hyperacute rejection. After the ex vivo reperfusion, group I xenografts had a significantly (P < .001) longer functional and histologic survival than did xenografts in groups II, III, and IV. Human blood reperfusing group I xenografts had a significantly (P < 0.05) lower (1) decline of clotting factors and total circulating immunoglobulins, (2) total and membrane attack complex (C5b,6,7,8,9) complement activation, and (3) hemolysis. By Western blot analysis, the in situ lung preperfusion removed antibodies against non-alpha-galactosyl proteins of low molecular weight that were not eliminated by the alpha-galactosyl column. CONCLUSIONS: Results demonstrate that specific depletion of anti-alpha-galactosyl antibodies alone incompletely protects pig lungs from hyperacute rejection. It is speculated that the more complete prevention of this rejection afforded by pig lung preperfusion relates to the removal of other, non-alpha-galactosyl antibodies.  相似文献   
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This study investigates the charge history of the Oligocene – Lower Miocene Asmari Formation reservoir at three oilfields (Karanj, Paranj and Parsi) in the southern Dezful Embayment, SW Iran, from microthermometric analyses of hydrocarbon-bearing fluid inclusions. The Asmari Formation reservoir was sampled in seven wells at depths of between 1671.5 and 3248.5 m; samples from three of the wells were found to be suitable for fluid inclusion analyses. The samples were analyzed using an integrated workflow including petrography, fluorescence spectroscopy, Raman microspectroscopy and microthermometry. Abundant oil inclusions with a range of fluorescence colours from near-yellow to near-blue were observed. Based on the fluid inclusion petrography, fluorescence and microthermometry data, two episodes of oil charging into the reservoir were identified: 7 to 3.5 Ma, and 3.5 to 2 Ma, respectively. Fluid inclusions in general homogenized at temperatures between 112 and 398°C and with salinities of 14 to 23 wt.% NaCl equivalent. Based on the burial history, the Albian Kazhdumi and Paleogene Pabdeh Formation source rocks in the study area have not reached the gas generation window. The abundant fluid inclusions containing gas-liquid phase observed in the Asmari samples studied are therefore inferred to have been derived from secondary oil-to-gas cracking which resulted from Late Pliocene uplift.  相似文献   
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Journal of Signal Processing Systems - Nowadays, Automatic Modulation Classification (AMC) plays an important role in many applications of cooperative and non-cooperative communication such as...  相似文献   
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BACKGROUND: A rat-to-primate cardiac xenograft model has been proposed as an alternative to the clinically relevant but more cumbersome pig-to-primate model for assessing the efficacy of strategies aimed at preventing xenograft hyperacute rejection. As in pig xenografts, the rejection of rat hearts was mediated by the binding of xenoreactive natural antibodies (XNA) and complement activation. The present study was conducted to identify target antigens recognized by cynomolgus and rhesus monkey IgM XNA on rat tissues and cells in comparison with pig cells. METHODS: The reactivity of rhesus or cynomolgus serum on pig and rat endothelial cells (ECs) was studied by flow cytometry, ELISA, and complement-dependent cytotoxicity, after removal of primate XNA by perfusion of pig livers, immunoadsorption on a Gal alpha(1,3)Gal affinity column, and enzymatic removal of alpha-galactosyl epitopes from the cell surface. Rat and pig EC extracts were also immunoprecipitated with primate serum and resolved in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The expression of the Gal alpha(1,3)Gal epitope was analyzed on rat tissues and ECs by immunohistochemistry, flow cytometry, and Western blot, using the isolectin B4 from Griffonia simplicifolia. RESULTS: Removal of primate XNA or of alphaGal epitopes resulted in a decrease in XNA binding to pig and rat cells, leaving a similar degree of residual reactivity in the two species. At least five proteins of 260, 210, 110, 56, and 50 kDa were immunoprecipitated on rat ECs, with molecular weight similar to several proteins identified on pig ECs. These results suggest that primate XNA recognize similar antigens on rat and pig ECs. Rat cells expressed lower levels of the Gal alpha(1,3)Gal epitope than pig cells. A large proportion, but not all, of primate XNA react with this epitope on pig and rat ECs. CONCLUSION: This study suggests that the rat is a valuable species for the evaluation of genetic engineering strategies on the vascular endothelium aimed at preventing hyperacute xenograft rejection.  相似文献   
6.
Fattahi  Nadia  Ramazani  Ali  Ahankar  Hamideh  Asiabi  Pegah Azimzadeh  Kinzhybalo  Vasyl 《SILICON》2019,11(3):1441-1450
Silicon - Tetramethylguanidine supported onto magnetic Fe3O4 nanoparticles (MNPs-TMG) was prepared and identified by several techniques such as TEM, XRD, SEM, FT-IR and TGA analyses. The...  相似文献   
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The molecularly imprinted polymer (MIP)-based electrochemical sensor has been attending recently, due to their exceptional advantages and specificity. Here, we successfully designed and fabricated a novel electrochemical nanosensor for determination of gallic acid (GA) based on its specific MIP. The MIP was synthesized using precipitation polymerization technique, via polymerization of methacrylic acid as a functional monomer. The MIP was applied in the multiwalled carbon nanotube-modified carbon paste electrode (MWCNT–CPE), and similarly, MIP and MWCNT-modified CPE (MIP–MWCNT–CPE) was prepared, which acted as the selective recognition element and pre-concentrator agent for GA. The effect of different factors such as quantity of MIP and MWCNT, GA solution pH, and GA accumulation time on an oxidation current of accumulated GA at the electrode were investigated and optimized by central composite design (CCD) as a an experimental design and response surface methodology. The results showed that fabricated nanosensors (MIP–MWCNT–CPE) have higher sensitivity compared with bare CPE, MWCNT–CPE, and MIP–CPE. This sensor showed a linear response range of 0.12–380.0 μM and detection limit of 47.0 nM. Finally, the nanosensor was applied to determine GA in apple, pineapple, orange juices, and a commercial green tea drink as real samples with satisfactory results.  相似文献   
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