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101.
目的通过研究辛伐他汀对动脉粥样硬化大鼠血管壁中细胞凋亡相关基因Fas及FasL蛋白表达产物的影响,探讨其在预防动脉粥样硬化发生中的可能机制。方法复制动脉粥样硬化大鼠模型,以辛伐他汀干预,取胸主动脉,观察其斑块变化,采用免疫组化Elivision法测定动脉粥样硬化血管壁中Fas、FasL蛋白表达。结果Fas蛋白表达在实验组明显高于对照组及干预组(P<0.01,P<0.05),实验组FasL蛋白表达也明显高于对照组及干预组(P<0.05)。结论Fas及FasL基因通过促进细胞凋亡作用而诱发动脉粥样硬化过程,辛伐他汀可通过调节细胞凋亡过程发挥抗动脉粥样硬化作用。  相似文献   
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103.
The Rhesus (Rh) blood group system is the most important blood group system in hemolytic disease of the fetus and newborn (HDFN). In clinical transfusions, the D antigen in the Rh blood group system comes third, behind antigens A and B which from ABO blood group system. Over the past decade, molecular technologies have been used to investigate the RHD allele in different ethnic groups. This review first introduces the basic structure of RhD protein and coding genes, then focuses on D-negative, weak D, partial D, DEL, RhDnull variants reported in the Chinese population. To date, more than 460 RHD variants have been reported around the world, but less than 70 RHD variants have been reported in the Chinese population. Further research is needed to identify more RHD polymorphism and establish criteria for blood detection and transfusion guidelines for RHD variants. Only in this way can we better guarantee the safety of blood transfusion and prevent the occurrence of HDFN. With the accumulation of research and clinical data, we should be clearer which RHD variants are to be regarded as RhD negative and which need to be regarded as RhD positive.  相似文献   
104.
The aim of this study was to investigate whether a moderate‐intensity static magnetic field (SMF) can enhance the killing effect of adriamycin (ADM) on K562 cells, and to explore the effects of SMF combined with ADM on K562 cells. We analyzed the metabolic activity of cells, cell cycle distribution, DNA damage, change in cell ultrastructure, and P‐glycoprotein (P‐gp) expression after K562 cells were exposed continuously to a uniform 8.8 mT SMF for 12 h, with or without ADM. Our results showed that the SMF combined with ADM (25 ng/ml) significantly inhibited the metabolic activity of K562 cells (P < 0.05), while neither ADM nor the SMF alone affected the metabolic activity of these cells. Cell ultrastructure was altered in the SMF + ADM group. For example, cell membrane was depressed, some protuberances were observable, and vacuoles in the cytoplasm became larger. Cells were arrested at the G2/M phase and DNA damage increased after cells were treated with the SMF plus ADM. ADM also induced the P‐gp expression. In contrast, in the SMF group and SMF + ADM group, the P‐gp expression was decreased compared with the ADM group. Taken together, our results showed that the 8.8 mT SMF enhanced the cytotoxity potency of ADM on K562 cells, and the decrease in P‐gp expression may be one reason underlying this effect. Bioelectromagnetics 32:191–199, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
105.
Paclitaxel is a widely used microtubule drug and cancer medicine. Here we report that by short exposure to paclitaxel at a low dose, multipolar spindles were induced in mitotic cells without centrosome amplification. Both TPX2 depletion and Aurora-A overexpression antagonized the multipolarity. Live cell imaging showed that some paclitaxel-treated cells accomplished multipolar cell division and a portion of the daughter cells went on to the next round of mitosis. The surviving cells grew into clones with varied genome content. The results indicated that an aneuploidy population could be induced by short exposure to paclitaxel at a low dose, implicating potential side effects of paclitaxel.  相似文献   
106.
107.
干旱对小麦幼苗诱导蛋白表达与某些生理特性的初步探讨   总被引:5,自引:0,他引:5  
试验以-1.2MPaPEG6000处理动小麦种子(TriticumaestlivumL.).SDS-PAGE图谱分析表明,水分胁迫诱导幼芽及整株均产生48.4kD、41.5kD二个蛋白质亚基。在幼根中未出现以上二个蛋白亚基。胁迫48h后,根干重/芽干重比呈上升趋势,幼芽细胞膜楔对透性增大和相对含水量降幅度均大于幼根。  相似文献   
108.
109.
从大规模癌样本基因突变扫查数据中识别癌基因具有重要的意义. 一些重要功能的改变对于癌的发生发展是必需的, 因此将它们定义为癌功能类, 并从GO(Gene Ontology)中选择一组显著富集已知癌基因的细致功能类来代表它们. 为了评价以癌相关功能类作为特征识别癌基因的效果, 将已知的蛋白激酶癌基因定义为阳性金标准, 而将其他的蛋白激酶基因定义为阴性金标准. 结果表明, 与利用选择压力作为特征的方法比较, 利用癌相关功能类作为特征的方法可以更有效地识别癌基因. 进一步结合癌相关功能类与基因非同义突变个数可以产生更可靠的预测结果. 最后, 将46个注释到癌相关功能类并且其非同义突变个数至少为3的蛋白激酶基因预测为癌基因, 预测精确率达到0.42.  相似文献   
110.
Multi-target EGFR, VEGFR-2 and PDGFR inhibitors are highly useful anticancer agents with improved therapeutic efficacies. In this work, we used two virtual screening methods, support vector machines (SVM) and molecular docking, to identify a novel series of benzimidazole derivatives, 2-aryl benzimidazole compounds, as multi-target EGFR, VEGFR-2 and PDGFR inhibitors. 2-Aryl benzimidazole compounds were synthesized and their biological activities against a tumor cell line HepG-2 and specific kinases were evaluated. Among these compounds, compounds 5a and 5e exhibited high cytotoxicity against HepG-2 cells with IC?? values at ~2 μM. Further kinase assay study showed that compound 5a have good EGFR inhibitory activity and moderate VEGFR-2 and PDGFR inhibitory activities, while 5e have moderate EGFR inhibitory activity and slightly weaker VEGFR-2 and PDGFR inhibitory activities. Molecular docking analysis suggested that compound 5a more tightly interacts with EGFR and PDGFR than compound 5e. Our study discovered a novel series of benzimidazole derivatives as multi-target EGFR, VEGFR-2 and PDGFR kinases inhibitors.  相似文献   
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