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991.
摘要:目的 检测胃癌细胞中T淋巴瘤侵袭转移诱导因子 1(Tiam 1)的表达,并分析其与胃癌细胞离体、在体侵袭转移能力的关系。方法 采用层粘连蛋白黏附法,由胃癌MKN 45细胞株(M0)中筛选获得高(MH)、低(ML)黏附亚株。应用RT PCR和定量细胞ELISA技术分别检测Tiam 1 mRNA与蛋白在M0,ML,MH细胞中的表达;应用Boyden小室法测定M0,ML,MH细胞的离体侵袭移行能力,并分析其与Tiam 1表达的关系。应用裸鼠接种法观察M0,ML,MH细胞的在体成瘤及转移能力。结果 MH细胞中Tiam 1 mRNA(RV=0.855±0.051)与蛋白的表达(RD=1.262±0.165)以及其离体侵袭转移能力(24.33±8.02,52.00±14.53)、在体裸鼠肺转移率(4/5=80%)均较M0细胞(RV=0.759±0.047,RD=0.911±0.104,11.67±3.79,26.00±9.54,2/5=40%),ML细胞(RV=0.743±0.039,RD=0.892±0.101,9.67±3.06,23.67±8.50,1/5=20%)为强,统计学差异显著(P< 0.05),但在M0,ML细胞间无统计学差异(P> 0.05);Tiam 1表达水平与胃癌细胞的侵袭转移能力呈完全及高度正相关(P< 0.05)。结论 Tiam 1表达水平升高有可能促进胃癌细胞侵袭转移能力的增强。 相似文献
992.
AIM: To determine the 2-year efficacy of continuous subcutaneous insulin infusion (CSII) following the current established criteria for funding of a National Health Service. METHODS: Longitudinal, prospective, observational unicentre study. Included in the study were 153 Type 1 diabetes (T1D) subjects, previously treated with multiple daily injections (MDI) of insulin, in whom CSII was started in accordance with the criteria for reimbursement of the Catalan National Health Service. At baseline, we recorded data on age, gender, duration of the disease, body mass index (BMI), insulin dose and indications for CSII. Glycated haemoglobin (HbA(1c)) and the frequency of hypoglycaemic events were used to assess glycaemic control. Quality of life was assessed using three different self-report questionnaires. After 24 months, these same items were remeasured in all subjects. Serious adverse events and injection-site complications were also recorded. RESULTS: In 96% of subjects, CSII indication included less than optimal glycaemic control using MDI. HbA(1c) fell from 7.9 +/- 1.3 to 7.3 +/- 1.1% (P < or = 0.001) after 24 months of CSII. Insulin requirements were significantly lower at the end of follow-up (0.55 +/- 0.21 U/kg body weight) in comparison with before use of CSII (0.70 +/- 0.20, P < or = 0.001). BMI increased from 24.0 +/- 3.1 to 24.4 +/- 3.2 kg/m(2) after 24 months (P < or = 0.025). The rate of episodes of diabetic ketoacidosis per year remained unchanged. Mild and severe hypoglycaemic episodes were significantly reduced. The scores in all subsets of the Diabetes Quality-of-Life (DQoL) questionnaire significantly improved after 24 months of CSII. CONCLUSIONS: CSII, commenced according to the criteria for a nationally funded clinical programme, improves glycaemic control and quality-of-life outcomes with fewer hypoglycaemic episodes in T1D subjects previously conventionally treated with MDI. 相似文献
993.
994.
Encephalopathy is a common complication of sepsis. However, little is known about the morphological changes that occur in the brain during sepsis. In this study, fecal peritonitis was induced in Wistar rats, which had been monitored for 4 h before their brains were removed and samples from the CA1 area taken. In addition to higher blood pressure with a decreasing pattern and a significant drop in rectal temperature, an increased heart rate and marked respiratory failure were observed. The tissue was investigated and compared with corresponding hippocampal samples taken from sham‐operated and not operated control groups. Significantly more peri‐microvascular edema was found in the hippocampal CA1 area in the septic group. The percentages of the peri‐microvascular edema were 158.57 ± 3.6%, 122.84 ± 1.5% and 120.24 ± 1.9% in the fecal peritonitis group, sham‐operated and not operated control groups, respectively. The results may suggest that the edema observed around the microvessels may participate in the pathogenesis of the septic encephalopathy probably by causing in the microvascular permeability characteristics. 相似文献
995.
靳维华 《航天医学与医学工程》2007,20(4):254-258
目的 探讨白细胞介素-1受体拮抗剂(interleukin-1 receptor antagonist,IL-1Ra)基因多态性与冠心病患病率及心血管事件发生的关系.方法 利用聚合酶链式反应(PCR)技术对220例冠心病患者及100例正常对照者IL-1Ra基因进行扩增;检测冠心病患者的高敏感性C反应蛋白、血清总胆固醇、甘油三酯、低密度脂蛋白和体重指数;所有冠心病患者随访12个月,了解患者在出院后1年内的心血管事件.结果 冠心病患者和正常人的IL-1Ra基因多态性分布的差别没有统计学意义;出院后未发生心血管事件的冠心病患者Ⅱ型基因型携带率高于其他基因型.结论 监测IL-1Ra基因多态性不能预测冠心病的发生;但其多态性中Ⅱ型基因对已患冠心病患者的预后有一定保护作用. 相似文献
996.
997.
Aksana I. Hubich Alexey Y. Bondar Tatsiana U. Kastsiuk Uladimir A. Kastsiuk Fyodar A. Lakhvich Mikhail V. Sholukh 《Hepatology research》2007,37(6):416-424
Aim: The cytoprotective effects of six novel synthetic prostaglandin A(2) analogs against carbon tetrachloride (CCl(4)) as a toxic agent were studied with isolated rat liver hepatocytes in vitro. Results: It was found that hepatocytes treatment with CCl(4) induced: (i) a significant increase of lactic dehydrogenase (LDH) release from cytoplasm; (ii) leakage of glutamate dehydrogenase (GDH) and acid phosphatase from mitochondria and lysosomes, respectively; (iii) 10-fold increase of trien conjugates formation; and (iv) a reduction of free SH-groups by 50%. Prostanoids U-26, U-9 and U-34 decreased cytotoxic index of CCl(4) on average by 1.5-2.0 times and were more effective than PGI(2), the well-known hepatoprotector of prostanoids type. The protective action of the prostanoids was not a cAMP- or Ca(2+)-dependent process. However, prostanoids U-26, U-9 and U-34 normalized intracellular content of SH-groups, reduced trien conjugates formation by 60-80% and strongly prevented enzyme leakage through cellular membranes. They were also able to inhibit CCl(4) effects via decreasing cytochrome P(450)2E1 activity. Conclusion: The results obtained demonstrate that prostanoids provide cytoprotective effects on liver hepatocytes through the prevention of lipid peroxidation of the plasma and the cellular membranes and maintenance of their barrier function. 相似文献
998.
目的通过测定细胞内5-Fu浓度的变化,判断5-Fu进入细胞的通道。方法细胞培养至2×107后,分为ENT非阻断组和ENT阻断组,前者培养基中仅加入100 ng/L的5-Fu,后者培养基中加入100μmol/L潘生丁和100 ng/L的5-Fu,分别作用15、30、1 h、2 h、4 h后收集细胞,测定细胞中5-Fu含量,并计算单细胞中5-Fu的浓度。结果ENT非阻断组和ENT阻断组细胞内5-Fu的含量,在五个位点上均有较大的差异性(P<0.01)。结论5-Fu既可通过ENT进入细胞,又可通过CNT进入细胞。 相似文献
999.
目的探讨褪黑素受体1B基因(MTNR1B)多态性与骨密度之间的相关性。方法选取140名16~20岁之间的正常女性,采用双能X线骨密度吸收仪测量双侧近端股骨的骨密度。同时,采取外周静脉血,采用试剂盒提取DNA。根据人类单倍体图计划(HapMap)提供的汉族人数据,我们在MTNR1B基因上选取了6个标签SNP(tagSNPs)。通过PCR-RFLP的方法检测褪黑素受体1B基因上6个标签SNP的基因型。采用ANOVA的统计学方法比较不同基因型对应骨密度大小。结果MTNR1B基因6个多态性位点各基因型所对应的骨密度,没有明显差异(P>0.05)。结论褪黑素受体1B基因多态性与骨密度之间没有相关性。 相似文献
1000.
目的探讨昆明地区汉族人群神经调节素1(NRG-1)基因SNPrs2954041多态性与精神分裂症及认知功能的关系。方法采用聚合酶链反应限制性片段长度多态性(PCR-RFLP)的方法检测141例精神分裂症患者和84名正常对照的NRG-1基因SNPrs2954041多态性;采用韦氏记忆量表(WMS)和威斯康辛卡片分类测验(WCST)评估两组人群的记忆功能和执行功能,并用PANSS量表评定患者的临床症状。结果两组NRG-1基因SNPrs2954041多态性的基因型和等位基因频率差异有统计学意义(2=34.01,P<0.05;2=30.201,P<0.05)。按性别分组后比较,结果仍同前。患者组中各基因型组间认知功能比较结果示:①各基因型组间韦氏记忆量表的理解记忆得分差异有统计学意义(P<0.05),两两比较显示G/G与T/T基因型患者间差异有统计学意义(P<0.05)。②G/G与T/T基因型患者比较,威斯康辛卡片分类测验中的错误数、持续错误数和分类个数差异有统计学意义(P<0.05)。结论NRG1基因SNPrs2954041多态性与精神分裂症存在关联,他也与精神分裂症患者的认知功能相关。 相似文献