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11.
将p R S T98 导入不含质粒且对抗菌药物敏感的大肠杆菌、伤寒杆菌,并用十二烷基硫酸钠( S D S) 消除耐药菌株的p R S T98 ,计算接合子及 R 质粒消除前后菌株在人、兔及豚鼠的不同浓度、不同成份血清中的存活率。p R S T98 介导其宿主菌对血清杀菌的抗性,但在不同宿主菌中抵抗力不同;补体经典途径及旁路途径均参与血清杀菌过程。p R S T9 8 具有多效性,其广泛的宿主性在介导细菌多重耐药的同时,还赋予细菌抵抗血清的杀菌作用,使病原菌致病性增强。  相似文献   
12.
This Capsular Lens (ONG, type IV, to be called O.C.L.) has been developed for routinely performed extracapsular cataract extraction with lens implantation. The fundamental surgical procedure was based on continuing experience with the bimanual aspiration-irrigation technique and system developed by the author in 1971. The biomechanical properties of the asymmetric partly flexible, haptic loops are designed to give tensionfree fixation in two capsular pockets. The plano-anterior position of the lens ensures well-defined irido-lenticular clearance and proper alignment of the convex side with the posterior capsule. Consequently no iridectomy or iridotomy is needed for proper aqueous flow.  相似文献   
13.
CD98 has been described to play a crucial role in tumor progression and survival. However, the role of CD98 in biliary tract cancer remains unclear. We found that 36.7% of all patients with biliary tract cancer had a high CD98 expression. Statistical analysis using Spearman's rank correlation showed that CD98 was significantly correlated with L-type amino acid transporter 1 (LAT1, r=0.562, P<0.001), Ki-67 (r=0.230, P=0.006) and CD34 (r=0.290, P=0.005). Multivariate analysis confirmed that a high CD98 expression was an independent prognostic factor for predicting poor outcome. CD98 is closely associated with tumor growth, biological aggressiveness, and survival of patients. With these data we proposed that CD98 expression is necessary for the development and pathogenesis of biliary tract cancer.(Hepatobiliary Pancreat Dis Int 2014;13:654-657)  相似文献   
14.
目的:探讨CD98与炎症性肠病(IBD)的关系。方法:雄性Balb/c小鼠48只,分为4组。正常对照组:不进行干预,自由饮食。生理盐水组:灌肠前禁食24 h,自由饮水,于实验第1、8及15天分别用100μL的生理盐水灌肠,灌肠后自由饮食。乙醇组:用体积分数50%乙醇溶液100μL灌肠,方法和步骤同生理盐水组。TNBS+乙醇组:第1、8及15天分别用2.0、2.5和3.0 mg TNBS加体积分数50%乙醇溶液100μL灌肠,建立TNBS诱发的小鼠实验性IBD模型。实验第21天,采用流式细胞仪检测外周血CD98的表达,免疫组化SABC法检测结肠黏膜上皮组织中CD98蛋白的表达。结果:4组小鼠外周血和结肠黏膜上皮组织中CD98蛋白表达的差异均有统计学意义(F=29.460,χ2=4.567,P<0.05),TNBS+乙醇组高于其他3组。结论:CD98可能参与了IBD的发生发展。  相似文献   
15.
目的 探讨微小RNA-148a-3p(miR-148a-3p)对丝裂原活化蛋白激酶激酶激酶9(MAP3K9)的靶向调控作用及对胃癌细胞增殖和凋亡的影响。方法 向对数生长期胃癌细胞株MGC-803转染miR-148a-3p模拟物(mimics组)和阴性对照(NC组),以未转染的MGC-803细胞为对照组;采用实时定量PCR(QPCR)检测各组miR-148a-3p水平以评价转染效率,MTT法检测各组细胞增殖能力,流式细胞术检测各组细胞凋亡情况,分别采用QPCR和Western blotting检测Bcl-2、Bax、caspase-3及MAP3K9 mRNA和蛋白水平,同时采用双荧光素酶报告实验验证miR-148a-3p与MAP3K9的靶向作用关系。结果 QPCR结果显示,对照组、NC组和mimics组的miR-148a-3p水平分别为1.021±0.123、1.087±0.196和2.854±0.368,与对照组和NC组比较,mimics组的miR-148a-3p水平升高(P<0.05)。mimics组MGC-803细胞的增殖活力较其余两组减弱(P<0.05)。mimics组MGC-803细胞凋亡率为(15.2±1.6)%,高于对照组的(3.5±0.9%)%和NC组的(4.5±1.1)%,差异具有统计学意义(P<0.05)。与对照组和NC组比较,mimics组的MAP3K9和Bcl-2的mRNA和蛋白水平均下调,而Bax和caspase-3的mRNA和蛋白水平均上调(P<0.05);双荧光素酶报告实验证实MAP3K9是miR-148a-3p的直接作用靶点。结论 MiR-148a-3p可抑制胃癌细胞MGC-803的增殖并诱导其凋亡,可能通过靶向MAP3K9来发挥抑癌作用,调控miR-148a-3p/MAP3K9轴在胃癌防治中有一定应用前景。  相似文献   
16.
《Molecular immunology》2015,68(2):183-192
FC-98, a synthesized benzenediamine derivate, was reported to regulate Toll-like receptor 9-induced activation of dendritic cells in our previous study. In this study, we evaluated the anti-inflammatory properties of FC-98 both in macrophages and in septic mouse models. By using enzyme-linked immunosorbent assay and real-time quantitative PCR, we found that FC-98 (6.25, 25 and 100 μM) dose-dependently attenuated lipopolysaccharide (LPS)-induced tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and monocyte chemoattractant protein (MCP-1) productions in RAW264.7 and primary mouse peritoneal macrophages. These inhibitory effects were not due to inducing cell cytotoxicity or altering LPS binding or TLR4 expression. Subsequently, western blot, immunofluorescence and luciferase reporter assays were used to investigate the underlying mechanisms of its anti-inflammatory activities. Results showed that FC-98 blocked activation of the c-Jun N-terminal kinase (JNK), nuclear factor-κB (NF-κB) and interferon regulatory factor 3 (IRF3) signaling pathways. In vivo, FC-98 (30 or 100 mg/kg) was intraperitoneally administrated into LPS-induced or CLP-induced sepsis mice. It was observed to enhance the survival rate, inhibit pro-inflammatory mediator production, improve organ injuries and suppress bacterial propagation. In conclusion, FC-98 effectively inhibited macrophage inflammatory responses and ameliorated sepsis in mice through down-regulation of both MyD88 and TRIF-dependent pathways. These results suggest that FC-98 could be a promising therapeutic agent for inflammatory diseases.  相似文献   
17.
Multiple sclerosis (MS) is a chronic inflammatory disease and the most common neurodegenerative status. MicroRNAs play an important role in macrophage response to inflammatory processes, and alterations in miRNA levels trigger the inactivation of specific T lymphocytes. As a result, these factors can lead to autoimmune diseases such as MS. Therefore, to determine the role of MicroRNA-146a and MicroRNA-155 in MS patients, their expression levels in serum of MS patients were compared with healthy controls.In this study, the expression levels of MicroRNA-146a and MicroRNA-155 in 30 serum samples of MS and healthy patients as a control group. MicroRNA extraction and cDNA synthesis was performed according manufacture protocols. The expression levels of MicroRNAs were evaluated by Real Time-PCR.MicroRNA-146a and MicroRNA-155 levels were increased in patients with MS compared to controls. The results demonstrated that EDSS score are increased with increasing level of MicroRNA-146a and MicroRNA-155. ROC curve analysis showed that the area under curve (AUC) was significant for MicroRNA-146a and MicroRNA-155.Increased expression levels of MicroRNA-146a and MicroRNA-155 may be associated with the pathogenesis of MS disease. If this study is conducted in a larger sample population and the above results can be used to identify patients or control patients who are under medical care.  相似文献   
18.
ObjectiveCavum veli interpositi (CVI) is a potential space below the splenium of corpus callosum and sometimes presents as a cyst.Materials and methodsIn this prospective cross-sectional study, 360 fetuses with normal second trimester scan and 152 s trimester fetuses with structural abnormalities were included.ResultsThe CVI cysts were more common in fetuses with brain anomaly compared to normal fetuses and fetuses with extra-central nervous system (CNS) anomalies (23% vs 18.3% and 18% respectively; p value < 0.01). The mean size of cysts in normal fetuses, fetuses with extra-CNS anomalies and fetuses with brain abnormalities was 4.6 mm, 5.8 mm and 9.2 mm respectively. There was a significant difference between cysts size in normal fetuses and fetuses with brain anomalies (p value < 0.01) and the cut-point was 7.1 mm.ConclusionThe prevalence of CVI cysts is more in fetuses with brain anomaly. Fetuses with a cyst size >7.1 mm need a more detailed brain examination.  相似文献   
19.
目的 探讨急性脑梗死(Acute cerebral infarction,ACI)患者血清微小RNA-497(MicroRNA-497,miR-497)、肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)的表达水平变化及其临床意义。方法 选取2016年1月-2019年11月本院收治的96例ACI患者,称ACI组,并选取本院同期98例体检健康者,称对照组; 采用实时荧光定量PCR(Real-time fluorescent quantitative PCR,qRT-PCR)法检测所有研究对象血清miR-497表达水平; 采用酶联免疫吸附法(Enzyme-linked immunosorbent assay,ELISA)检测所有研究对象血清肿瘤坏死因子-α水平; 评估ACI患者神经功能缺损程度、计算脑梗死体积,比较不同神经功能缺损程度/脑梗死体积的ACI患者血清miR-497、TNF-α水平; Pearson法分析ACI患者血清miR-497、TNF-α水平与神经功能缺损程度评分(National institutes of health stroke scale,NIHSS)、脑梗死体积的关系; 采用受试者工作特征曲线(Receiver operating characteristic curve,ROC)评价血清miR-497、TNF-α对ACI的诊断价值。结果 ACI组血清miR-497、TNF-α水平均明显高于对照组(P<0.05); ACI患者血清miR-497、TNF-α水平随神经功能缺损程度加重、脑梗死体积增加均呈递增趋势(P均<0.05); ACI患者血清miR-497、TNF-α水平与脑梗死体积、NIHSS评分均呈正相关(r=0.423,0.514,0.542,0.399,P均<0.05); 血清miR-497、TNF-α对ACI诊断的曲线下面积(Area under curve,AUC)为0.848、0.806,截断值分别为1.29、1.27,相应灵敏度分别为82.3%、81.3%,特异度分别为76.5%、77.6%; 两者联合诊断ACI的AUC为0.907,其灵敏度、特异度分别为81.3%、90.8%。结论 miR-497、TNF-α在ACI患者血清中表达均上调,且与神经功能缺损程度、脑梗死体积有关,均可能在ACI进展中起一定作用,两者联合可有效提高ACI的诊断效能,有助于诊断、评估ACI患者的病情。  相似文献   
20.
We previously showed that microRNA-429 (miR-429) played an important role in epithelial–mesenchymal transition (EMT) of urothelial cell carcinoma of the bladder. We herein evaluated the expression of miR-429 in bladder cancer and its potential relevance to clinicopathological characteristics and patient survival. Relative expression levels of miR-429 in surgical bladder cancer tissue specimens obtained from 76 patients with bladder cancer were measured by chromogenic in situ hybridization. miR-429 expression was significantly higher in specimens from alive patients than expired patients in both of 5-year overall survival (OS) (0.59 ± 0.09 vs. 0.27 ± 0.12; p < 0.05) and 5-year recurrence-free survival (RFS) (0.63 ± 0.10 vs. 0.33 ± 0.10; p < 0.05). The univariate Cox proportional hazards analysis revealed that tumor grade, stage, and miR-429 expression were significantly associated with patient survival. In multivariate analysis, tumor stage and miR-429 expression were significantly associated with 5-year OS (hazard ratio [HR] 4.70, p < 0.001) and 5-year-RFS (HR 2.20, p < 0.05). The Kaplan–Meier analysis showed that patients with miR-429 expression had significantly better 5-year OS and 5-year RFS rates than those without miR-429 expression (84.4% vs. 61.4%, p < 0.05 and 71.9% vs. 45.5%, p < 0.05, respectively). miR-429 may be considered as an adjunctive prognostic marker in addition to tumor grade and stage in bladder cancer.  相似文献   
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