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1.
ObjectiveWe investigated whether glutamate, NMDA receptors, and eukaryote elongation factor-2 kinase (eEF-2K)/eEF-2 regulate P-glycoprotein expression, and the effects of the eEF-2K inhibitor NH125 on the expression of P-glycoprotein in rat brain microvessel endothelial cells (RBMECs).MethodsCortex was obtained from newborn Wistar rat brains. After surface vessels and meninges were removed, the pellet containing microvessels was resuspended and incubated at 37°C in culture medium. Cell viability was assessed by the MTT assay. RBMECs were identified by immunohistochemistry with anti-vWF. P-glycoprotein, phospho-eEF-2, and eEF-2 expression were determined by western blot analysis. Mdr1a gene expression was analyzed by RT-PCR.ResultsMdr1a mRNA, P-glycoprotein and phospho-eEF-2 expression increased in L-glutamate stimulated RBMECs. P-glycoprotein and phospho-eEF-2 expression were down-regulated after NH125 treatment in L-glutamate stimulated RBMECs.ConclusionseEF-2K/eEF-2 should have played an important role in the regulation of P-glycoprotein expression in RBMECs. eEF-2K inhibitor NH125 could serve as an efficacious anti-multidrug resistant agent. 相似文献
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从最高人民法院的一个典型案例出发,探讨药物组合物封闭式权利要求保护范围的解读及其专利侵权判定标准,比较其他国家
的相关规定和判例,并对药物组合物封闭式权利要求的专利授权、确权审查、侵权判定以及申请文件撰写技巧提出见解,以供借鉴和参考。 相似文献
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四川雅安常见住区蝇类密度监测 总被引:2,自引:0,他引:2
根据全国常见住区蝇类密度监测课题组关于“全国常见住区蝇类密度监测实施计划”安排,雅安地区定力全国七个监测点之一,作者承担了这一任务。该项工作尚在继续进行中,现将1988年监测结果报道如下。 相似文献
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Ming-Ya Li Qing-Shan Yan Lori L. Coffey Maarten E. A. Reith 《Journal of neurochemistry》1996,66(2):559-568
Abstract: Monoamine-uptake blockers were applied focally (0.1–1,000 µ M ) through a dialysis probe in the nucleus accumbens of freely moving rats, and the extracellular concentrations of dopamine, norepinephrine, and serotonin were measured. The selective dopamine-uptake blocker GBR 12935 increased dopamine preferentially with only a small effect on norepinephrine, whereas the selective serotonin-uptake blocker fluoxetine increased serotonin output preferentially. In contrast, the selective norepinephrine-uptake blockers desipramine and nisoxetine enhanced not only norepinephrine, but also serotonin and dopamine appreciably. Cocaine increased all three amines with the greatest effects on dopamine and serotonin. As in our previous study on the ventral tegmental area, there was a positive association between dopamine and norepinephrine output when all blocker data were taken together. The present results suggest a contribution of the increase in norepinephrine, but not serotonin, to the enhancement of dopamine after cocaine applied focally in the nucleus accumbens. 相似文献
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Protein factors that bind to the murine 2',5'-oligoadenylate synthetase ME-12 gene 5' upstream regulatory region 总被引:1,自引:0,他引:1
The murine 2',5'-oligoadenylate synthetase ME-12 gene regulatory region AB forms six complexes with protein factors in murine BALB/c 3T3 cells as demonstrated by the mobility shift electrophoresis assay under the reaction conditions used. The complexes, designated C1-C6 in order of their decreasing electrophoretic mobility, showed three distinctive specificities with regulatory region AB, element A, and element B as probes or competing DNA: 1) C1 is region AB-specific (this complex did not form with either element A or B used alone or as a mixture); 2) C5 formed both with element A and element B; 3) C2, C3, C4, and C6 formed with element B, but not A. The protein factors that give rise to these complexes show differential DNA binding activities in various buffer solutions at different pH values. The C4-forming protein factor is the interferon (IFN)-alpha/beta-stimulated response factor (ISRF) which shows element B specificity. It preexists in the cytoplasm. ISRF appears to be complexed to an inhibitor (ISRFI) in the cytoplasm and to dissociate from the inhibitor and to translocate into the nucleus upon treatment of cells with IFN-alpha/beta. We propose that IFN-alpha/beta treatment of BALB/c 3T3 can trigger at least two events: 1) loosening of a tight inhibitor-ISRF complex with the release of free ISRF; this may be mediated via phosphorylation of ISRF or ISRFI; 2) translocation of ISRF into the nucleus and binding to the enhancer element B, which results in the activation of 2',5'-oligoadenylate synthetase gene expression. 相似文献
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Yan Xue Liu Jia Wu Ke-Xin Yang Nan Pan Li-Ben Song Ying Liu Yang Tang Zhong-Hua 《Journal of Plant Growth Regulation》2022,41(6):2421-2434
Journal of Plant Growth Regulation - Early-spring plants are a special type of plant that complete their life cycle promptly in cold, early spring. Very little effort has been made into researching... 相似文献
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A simple phosphorescence method is proposed for quercetin detection based on Al3+-amplified room-temperature phosphorescence (RTP) signals of 3-mercaptopropionic acid (MPA)-capped Mn-doped ZnS quantum dots (QDs). The sensor was established based on some properties as follows. Al3+ can interact with carboxyl groups on the surface of MPA-capped Mn-doped ZnS QDs via chelation, which will lead to the aggregation of QDs and amplification of RTP signals, After the addition of quercetin, it can form more stable complex with Al3+ in alkaline aqueous solution and dissociate Al3+ from the surface of Mn-doped ZnS QDs, which will result in significant recovery of RTP intensity of the MPA-capped Mn-doped ZnS–Al3+ system. Under the optimized conditions, the change of RTP intensity was proportional to the concentration of quercetin in the range from 0.1 to 6.0 mg L−1, with a high correlation coefficient of 0.996 and a detection limit of 0.047 mg L−1. The proposed method is potentially suitable for detection of quercetin in real samples without complicated pretreatment. 相似文献
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