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41.
 目的:研究星形细胞上调基因1(astrocyte elevated gene-1,AEG-1)在人宫颈鳞癌细胞和组织中的表达,探讨AEG-1表达下调对宫颈癌SiHa细胞细胞周期和侵袭能力的影响,并分析其可能的分子机制。方法:采用Western blotting检测正常宫颈组织、宫颈鳞癌组织、HeLa、SiHa和CaSki细胞中AEG-1蛋白的表达。将对照siRNA和AEG-1 siRNA分别转染SiHa细胞,利用Western blotting检测SiHa细胞中AEG-1蛋白的表达,采用流式细胞术检测细胞周期分布的变化,采用Boyden小室检测细胞侵袭能力的变化,最后采用Western blotting检测cyclin D1、细胞周期素依赖性激酶 2(CDK2)和基质金属蛋白酶9(MMP-9)蛋白表达的变化。结果:宫颈鳞癌组织中AEG-1蛋白表达显著高于正常宫颈组织(P<0.05),同时3株宫颈癌细胞中AEG-1蛋白表达均显著高于正常宫颈组织,其中SiHa细胞中AEG-1蛋白表达最高(P<0.05)。此外,AEG-1 siRNA能显著下调SiHa细胞中AEG-1蛋白的表达(P<0.05),其表达下调能明显促使SiHa细胞在G0/G1期的比例增加和降低其侵袭能力。Western blotting结果表明,AEG-1 siRNA组中cyclin D1、CDK2和MMP-9蛋白的表达均显著低于未处理组和对照siRNA组(P<0.05)。结论:AEG-1在宫颈癌中的高表达可能与宫颈癌的发生发展密切相关,其表达下调介导的细胞周期静止和侵袭能力降低可能与cyclin D1、CDK2和MMP-9蛋白表达下调密切相关。  相似文献   
42.
 目的:探讨槲皮素对人卵巢癌SKOV-3细胞增殖抑制和凋亡的影响,为卵巢癌临床治疗提供依据。方法:不同浓度槲皮素处理卵巢癌SKOV-3细胞后,采用MTT实验检测细胞增殖抑制作用并计算抑制率,细胞免疫化学染色法鉴定细胞凋亡,流式细胞术检测细胞周期及细胞凋亡。结果:槲皮素能够抑制SKOV-3细胞的增殖,且呈时间和剂量依赖性,免疫荧光显示槲皮素对SKOV-3细胞具有诱导凋亡作用,流式细胞术显示SKOV-3细胞被阻滞在S期, G2/M期细胞比例降低,凋亡率上升。结论:槲皮素在体外能够抑制卵巢癌SKOV-3细胞的增殖,阻止细胞由S期向G2期移行,促进其凋亡。  相似文献   
43.
目的 为膝关节前交叉韧带损伤分度提供新的影像诊断依据。 方法 选取膝关节弥散张量成像扫描检查正常者100例和单侧前交叉韧带撕裂伤者100例,后者按照损伤程度分为Ⅰ~Ⅳ级,在工作站划分前交叉韧带损伤处及正常组相应部位感兴趣区,测量各向异性分数(fractional anisotropy,FA)和表观弥散系数(apparent diffusion coefficient,ADC),生成纤维示踪图像。 结果 前交叉韧带损伤处与正常组相应部位的FA和ADC差异有统计学意义,损伤处的FA低于正常组,ADC高于正常组。前交叉韧带Ⅰ级、Ⅱ级、Ⅲ级、Ⅳ级损伤处的FA和ADC差异有统计学意义,FA随损伤程度增高而逐渐降低,与损伤程度呈负相关;ADC则逐渐增高,与损伤程度呈正相关。FA和ADC、纤维示踪成像及MRI诊断前交叉韧带损伤程度分级的灵敏度、特异度、准确度、阳性预测值及阴性预测值差异均有统计学意义,从高到低均依次为纤维示踪成像、FA和ADC、MRI。 结论 膝关节前交叉韧带损伤处的FA和ADC与损伤程度密切相关,纤维示踪成像可以提高损伤程度分级的准确率,弥散张量成像可以为前交叉韧带损伤分级提供更准确的影像诊断依据。  相似文献   
44.
目的 观察椎动脉和第1颈神经穿经硬膜处的形态特点及毗邻结构,探讨高血压合并枕颈部疼痛的发生机制。 方法 头颈部标本18具,解剖剥离法暴露,观察椎动脉穿经硬膜处部位及毗邻结构、椎动脉与第1颈神经(C1)的位置关系。 结果 椎动脉在寰枕外侧关节内后侧穿经硬膜,穿经处形成边缘光滑的圆孔,直径6.5~9.0 mm,硬膜与椎动脉外膜由纤维结缔组织连结。C1神经前后根自脊髓发出向外侧走行于椎动脉内侧并在其下方相伴共同穿经硬膜孔(100%),其中与动脉壁相贴者66.7%(12例);神经嵌入动脉壁者22.2%(4例);隔有硬膜组织者11.1%(2例)。C1神经根出孔后走行于椎动脉与椎动脉沟之间。 结论 椎动脉穿经硬膜孔处位置固定,孔边缘致密,限制椎动脉扩张,利于颈椎活动时维持椎动脉供血,当全身血压波动时椎动脉管径不会产生明显变化,以维持后循环血液动力学稳定,但血压升高有可能将C1颈神经根卡压在硬膜边缘,椎动脉搏动刺激C1颈神经根导致椎枕肌痉挛,出现枕颈部疼痛。这可能是高血压合并枕颈部症状的形态学基础。  相似文献   
45.
Heart failure (HF) is a major cause of death in cardiovascular diseases worldwide, and its molecular mechanisms and effective prevention strategies remain to be further studied. The myocardial cytoskeleton plays a pivotal role in many heart diseases. However, little is known about the function of the membrane cytoskeleton 4.1 protein family and related regulatory mechanisms in the pathogenesis of HF. In this study, we detected the localization and expression of the protein 4.1 family and ion channel proteins in a rat HF model induced by doxorubicin (DOX), and studied the interactions between them. Our results showed that compared with the control group, the HF group displayed an increased expression level of protein 4.1R and decreased levels of protein 4.1 G and 4.1 N. The Nav1.5 protein levels were significantly increased, while the SERCA2a and Cav1.2 protein levels were significantly decreased in the HF group. Furthermore, there is co-localization and interaction between protein 4.1R and Nav1.5, protein 4.1 G and SERCA2a, protein 4.1 N and Cav1.2, respectively. Taken together, the results indicated that the protein 4.1 family might be involved in the occurrence and development of HF through its interaction with ion channel proteins, suggesting that 4.1 proteins may serve as a novel therapeutic target for HF.  相似文献   
46.
A bagasse-based 3D carbon matrix (BC) with high specific surface area and high conductivity was obtained by carbonization and pore-forming processes with bagasse as the carbon precursor and K2FeO4 as the pore-former. The microporous structure and nitrogenous functional groups were determined in the prepared carbon matrix, which could allow high sulfur loading and improve the polysulfide absorption capacity during cycling. After sulfur infusion, the S/BC composite with 68.8% sulfur content was obtained. The lithium–sulfur (Li–S) battery with the S/BC cathode shows high specific capacity and good cycling performance. It delivers a specific capacity of 1360 mA h g−1 at 0.2C and remains at 790 mA h g−1 after 200 cycles. At 1C, the Li–S with this composite cathode exhibits 601 mA h g−1 after 150 cycles. This work offers a new kind of green material and a new method for Li–S batteries.

Bagasse-based carbon matrix with microporous structure and nitrogenous functional groups could have high sulfur loading and excellent polysulfide absorption capacity.  相似文献   
47.
《Seminars in Arthroplasty》2015,26(4):218-228
Technical issues such as instability, mal-rotation, and mal-alignment continue to be issues leading to total knee replacement revision. Soft tissue balancing is critical to successful address these issues for successful total knee replacement outcomes. Intra-op sensors can now be used to dynamically balance knees in real time and mitigate negative outcomes.  相似文献   
48.
Background: Vincristine (VCR) is a chemical that is widely used in tumor therapy. While long-term use can make tumor cells resistant to VCR, the underlying mechanisms of this resistance are still unclear. Objective: This study aimed at investigating the role of microRNA (miRNA) in colon cancer drug resistance. Methods: HCT-8 colon carcinoma cells were cultured and treated with different VCR concentrations to establish an HCT-8/VCR resistant cell line. Whole-genome screens, HiSeq 2500 sequencing, and bioinformatics methods were used to detect and analyze differences in miRNA expression between the drug-resistant HCT-8/VCR cells and non-resistant HCT-8 cells. Differential expression profiles of miRNAs were constructed based on sequencing result. Results: The HCT-8/VCR resistant colon carcinoma cell line was established. With regard to the difference in drug resistance between HCT-8/VCR and HCT-8 cells, 24 miRNAs showed statistically significant differences in their expression (fold change > 4), of which 17 were up-regulated. Seven miRNAs were down-regulated. Conclusion: As abnormal expression of miRNAs was associated with VCR resistance of colon carcinoma cells, differences in miRNA expression may play a key role in VCR resistance of colon cancer cells.  相似文献   
49.
Objective To investigate whether exposure to particulate matter of diameter equal to or less than 2.5 μm(PM_(2.5)) alters the response of lung epithelial cells to extrinsic regulation by globally profiling cell surface ligands and quantifying their binding activity.Methods Human A549 lung epithelial cells(LECs) were treated with or without PM_(2.5). Ligandomic profiling was applied to these cells for the global identification of LEC-binding ligands with simultaneous quantification of binding activity. Quantitative comparisons of the entire ligandome profiles systematically identified ligands with increased or decreased binding to PM_(2.5)-treated LECs.Results We found 143 ligands with increased binding to PM_(2.5)-treated LECs and 404 ligands with decreased binding. Many other ligands showed no change in binding activity. For example,apolipoprotein E(ApoE), Notch2, and growth arrest-specific 6(Gas6) represent ligands with increased,decreased, or unchanged binding activity, respectively. Both ApoE and Gas6 are phagocytosis ligands,suggesting that phagocytic receptors on LECs after stimulation with PM_(2.5) were differentially upregulated by PM_(2.5).Conclusion These results suggest that the newly-developed ligandomics is a valuable approach to globally profile the response of LECs to PM_(2.5) in terms of regulating the expression of cell surface receptors, as quantified by ligand binding activity. This quantitative ligandome profiling will provide indepth understanding of the LEC molecular response on the cell surface to particulate matter air pollution.  相似文献   
50.
目的 探讨食管超声引导下经胸外科封堵术治疗先天性心脏病的疗效和预后.方法 选取2016年1月至2018年12月在我院行食管超声引导下经胸外科封堵治疗的先天性心脏病患者52例为研究组,同期行体外循环下修补治疗患者53例为对照组,记录并比较两组患者手术时间、术中出血量、输血量、呼吸机辅助时间、ICU停留时间、血管活性药物使用情况及术后住院时间、并发症发生率等指标,术前及出院前均采用经胸超声心动图对患者心脏结构功能进行评价,术后随访12个月观察预后情况.结果 两组患者全部手术成功,均无死亡和危及生命的严重并发症.研究组手术时间(72.69±6.14)min、术中出血量(29.96±5.99)ml、输血比例(1.92%)、呼吸机辅助时间(132.70±13.21)min、ICU停留时间(11.85±1.43)h、住院时间(6.83±0.49)d均明显少于对照组的(130.50±3.53)min、(112.80±11.93)ml、(28.30%)、(217.20±19.02)min、(20.60±0.71)h、(8.34±0.39)d(P<0.01).血管活性药物使用比例(32.69%)也明显低于对照组(90.57%),两组总并发症发生的差异也有统计学意义.术后3、6、12个月随访超声心动图检查示,52例患者封堵器均位置良好,未见残余分流及血栓形成,心电图也未见严重心律失常.结论 食管超声引导下经胸外科封堵治疗先天性心脏病是一种安全有效的方法,具有创伤小、易操作、恢复快等优点.  相似文献   
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