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排序方式: 共有834条查询结果,搜索用时 15 毫秒
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目的 观察survivin特异性siRNA对胰腺癌细胞株Panc-1细胞增殖和凋亡的影响.方法 体外构建Survivin特异性siRNA表达载体p-Survivin-siRNA,转染胰腺癌细胞株Panc-1细胞系,RT-PCR和Western印迹法检验其对胰腺癌细胞株Panc-1细胞的RNA干扰(RNAi)效果.采用MTT法分析其对细胞增殖的影响,流式细胞仪检测其对细胞周期的影响.同时,采用Western印迹法检测半胱氨蛋白酶 3(caspase 3)的表达变化.结果 p-survivin-siRNA表达质粒高效而特异地剔降胰腺癌细胞株Panc-1细胞中survivin的表达,抑制肿瘤细胞增殖(P<0.01),阻断胰腺癌细胞株Panc-1细胞在G1期.随着survivin基因被沉默,caspase 3表达升高(P<0.01).结论 靶向survivin基因的siRNA表达载体可以显著抑制胰腺癌细胞株Panc-1细胞增殖,促进细胞凋亡. 相似文献
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The productive activation of CD4(+) T lymphocytes, leading to proliferation and cytokine secretion, requires precise temporal regulation of intracellular cyclic AMP concentrations. The major effector molecule activated by cyclic AMP in mammalian cells is the cyclic AMP-dependent protein kinase A (PKA). The type I PKA isozyme mediates the inhibitory effects of cyclic AMP on T-cell activation. Using laser scanning confocal microscopy, we demonstrated that the regulation of PKA type I activity involves spatial redistribution of PKA type I molecules following T-cell receptor (TCR) stimulation. In resting T cells, PKA type I was located in membrane proximal regions and distributed equally across the cell. Shortly after antigen engagement, T cells and antigen-presenting cells formed an area of intense contact, known as the immunological synapse. TCR concentrated at the synapse, whereas PKA type I molecules redistributed to the opposite cell pole within 10 min after T-cell stimulation. Type I PKA redistribution was solely dependent on TCR signalling, because we observed the same temporal and spatial distribution after antibody-mediated cross-linking of the TCR-associated CD3 complex. Segregation of TCR and PKA type I molecules was maintained for at least 20 min. Thirty minutes after stimulation, PKA type I partially colocalized with the TCR. After 60 min, PKA type I distribution again approached the resting state. Considering that initial TCR signals lead to increases in intracellular cyclic AMP, PKA type I molecules may be targeted towards localized cyclic AMP accumulations or transported away from these areas, depending on the requirements of the cellular response. 相似文献
4.
High-Throughput Generation of P. falciparum Functional Molecules by Recombinational Cloning 总被引:2,自引:0,他引:2
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Joo Carlos Aguiar Joshua LaBaer Peter L. Blair Victoria Y. Shamailova Malvika Koundinya Joshua A. Russell Fengying Huang Wenhong Mar Robert M. Anthony Adam Witney Sonia R. Caruana Leonardo Brizuela John B. Sacci Jr. Stephen L. Hoffman Daniel J. Carucci 《Genome research》2004,14(10B):2076-2082
Large-scale functional genomics studies for malaria vaccine and drug development will depend on the generation of molecular tools to study protein expression. We examined the feasibility of a high-throughput cloning approach using the Gateway system to create a large set of expression clones encoding Plasmodium falciparum single-exon genes. Master clones and their ORFs were transferred en masse to multiple expression vectors. Target genes (n = 303) were selected using specific sets of criteria, including stage expression and secondary structure. Upon screening four colonies per capture reaction, we achieved 84% cloning efficiency. The genes were subcloned in parallel into three expression vectors: a DNA vaccine vector and two protein expression vectors. These transfers yielded a 100% success rate without any observed recombination based on single colony screening. The functional expression of 95 genes was evaluated in mice with DNA vaccine constructs to generate antibody against various stages of the parasite. From these, 19 induced antibody titers against the erythrocytic stages and three against sporozoite stages. We have overcome the potential limitation of producing large P. falciparum clone sets in multiple expression vectors. This approach represents a powerful technique for the production of molecular reagents for genome-wide functional analysis of the P. falciparum genome and will provide for a resource for the malaria resource community distributed through public repositories. 相似文献
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To solve the problems existing in passive biochip systems, we designed a novel active biochip system. This system introduces negative pressure and controlling devices to adjust the antigen-antibody reaction on the nitrocellulose membrane. Computational simulation demonstrated that this system is a rapid, stable, robust and practical system that may enhance the efficiency of antigen-antibody reactions and improve the repeatability and accuracy of biochip analysis. 相似文献
7.
博乐欣与阿米替林治疗抑郁障碍对照观察 总被引:1,自引:0,他引:1
目的:探讨博乐欣与阿米替林对抑郁障碍的疗效及副反应。方法:对50例抑郁障碍患者应用博乐欣(25例)与阿米替林(25例)进行对照治疗,疗程6周。 相似文献
8.
Ping Gao Yinglin Lu Xueming Ge Wenhong Fan Shengfa Fu Shuang Liu Heping Yang 《中国癌症研究》1997,9(3):192-194
In order to investigate TGFβ1 gene expression and its effect on murine tumor growth following direct intratumoral injection
of naked plasmid DNA encoding human TGFβ1, LM3 murine lung adenocarcinoma cells were inoculated subcutaneously to T739 mice and grew to tumor nodules in 2 weeks. Multiple direct intratumoral injection of plasmid DNA, PMAMneo- TGFβ1, were given
and compared with saline or vector plasmid administration groups. The growth of tumor was observed till the 8th week when
the mice were killed for Northern blot analysis and histopathological study of tumoral tissue. The results showed that the
growth of tumor was boosted in the TGFβ1 gene treated mice as compared with the control groups, whereas there was no significant
difference in the metastatic behavior. Northern blot showed efficient expression of TGFβ1 mRNA in the treated group. The present
study indicated that TGFβ1 may stimulate tumor growthin vivo through certain mechanisms. And direct intra-tumoral injection of nude plasmid DNA may be a promising gene transfer strategyin vivo.
This work was supported by the National Natural Science Foundation of China (No. 39370761). 相似文献
9.
聚合酶链反应检测细菌16S rRNA基因 总被引:2,自引:0,他引:2
根据细菌16SrRNA基因的高度保守性,设计合成所有细菌、革兰氏阳性细菌及革兰氏阴性细菌的共同引物,采用聚合酶链反应检测已知细菌13株,三对引物分别扩增的阳性率为100%,倍比稀释法能检出细菌的最低浓度为4CFU·ml-1,同时检测临床样本40份,阳性率为675%(27/40),同期细菌培养阳性率为45%(18/40),二者比较差异有显著性(P<0.05)。结果提示聚合酶链反应检测细菌16SrRNA基因具有高度的特异性和敏感性。 相似文献
10.
前列腺增生症术后排尿困难的原因与防治(附26例分析) 总被引:2,自引:0,他引:2
目的 分析各种常见前列腺切除术后排尿困难的原因,为预防和治疗提供依据。方法 回顾分析26例前列腺切除术后发生梗阻患者的资料。耻骨上前列腺切除术后排尿困难22例,TURP术后4例。患者均有不同程度的排尿困难、尿线变细,12例呈滴沥状排尿,5例发生急性尿潴留。结果 膀胱颈挛缩6例(23%).后尿道狭窄6例(23%),腺体残留或复发4例(15.4%),膀胱颈水肿3例(11.6%),血块或脱落组织堵塞2例(7.7%).逼尿肌无力2例(7.7%),输尿管间嵴肥厚2例(7.7%),前尿道狭窄1例(3.9%)。除2例逼尿肌无力者分别行自家清洁导尿和永久性膀胱造瘘外,余经处理均愈。结论前列腺增生症术后排尿困难的原因较多,主要是手术操作及术前、术后处理不当所致。一旦发生,则可根据不同原因采取不同方法治疗,效果较佳。 相似文献