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41.
AIM: To investigate the effects of NF-κB decoy oligodeoxynucleotides (ODNs) on apoptosis in lung cancer cell A549. METHODS: The treatments of lung cancer cells (A549) were divided into three groups: group A (control group); group B (decoy ODN group) and group C (scramble decoy ODN group). FITC-labeled NF-κB decoy ODNs was transfected into A549 with LipofectAMINETM2000. The activation was observed by electrophoretic mobility shift assays (EMSA). The proliferation was observed by growth curve. The apoptosis of cells were observed by flow cytometry and TdT mediated dUTP-biotin Nick End Labeling (TUNEL). The expression of Bcl-2 and Fas were observed by Western blot. RESULTS: After FITC-labeled decoy ODNs was transfected for 1 hour, the decoy ODNs was detected in the nuclei of A549 cells. EMSA performed the depression of the NF-κB binding to the nucleus. The growth curve showed the inhibition of the A549 cell growth and the percentage of apoptosis was increased compare with control group by flow cytometry and TUNEL. The amount of apoptosis inhibitor (Bcl-2) in group A and group C were 2.0 times and 2.1 times more than that in group B, respectively. The level of apoptosis accelerator (Fas) in group B were 2.6 times and 2.3 times more than that in group A and group C, respectively via Western blot. CONCLUSION: The NF-κB decoy ODNs accelerate the apoptosis of lung cancer cell A549 and the mechanism may be due to its inhibiting the expression of Bcl-2 and increasing the level of Fas.  相似文献   
42.
维生素E对绵羊鲜精及冻精精液品质的影响   总被引:5,自引:0,他引:5  
日粮中添加维生素E可以提高绵羊鲜精的活率 ,对照组和试验组的活率分别为 0 72± 0 0 7和 0 78± 0 0 6(P <0 0 5 ) ,显著改善鲜精精液品质。采用两步稀释法在绵羊冷冻精液稀释液中添加维生素E ,可以极显著降低冷冻对精子顶体的冷刺激损害程度 ,试验组的活率 ( 0 43 5± 0 0 2 0 )极显著高于对照组 ( 0 3 65± 0 0 2 6) (P <0 0 1) ,精子顶体的总异常率试验组 ( 3 3 72 % )极显著低于对照组 ( 4 4 3 5 % ) (P <0 0 1) ,其中试验组顶体膨胀率和脱落率与对照组分别为 1 2 8%±0 5 8%、2 3 0 8%± 1 45 %与 2 68%± 0 5 9%、2 8 96%± 3 14 %。冷冻精液品质显著改善。  相似文献   
43.
运用免疫组织化学超敏 SP法对山羊胎儿脊髓发育中神经生长因子 (nerve growth factor,NGF)及其高亲和力受体 Tr KA的表达及其功能进行了系统的研究和探讨。结果显示 ,山羊胎儿脊髓灰质中存在 NGF及其受体 Tr KA,于 6周龄胚就可检测到 ,随胚龄增加 ,其表达范围及免疫反应着色程度逐渐增强。 NGF主要分布于腹角和背角的神经细胞 ,反应产物主要定位于胞质和突起 ;Tr KA的分布主要以腹角及胶状质为主 ,反应产物主要定位于胞核 ,后期胞质及突起也可见到阳性反应。在山羊胎儿脊髓白质中也可观察到 NGF及 Tr KA免疫阳性反应 ,其发育后期更为显著 ,阳性反应主要分布于神经胶质细胞核、神经纤维的轴索及雪旺氏细胞。结果提示 ,NGF不仅对交感和感觉神经元的发育起作用 ,而且还与腹角运动神经元的发育有关  相似文献   
44.
45.
Systemic acquired resistance (SAR) is induced following inoculation of Peronospora tabacina sporangia into the stems of Nicotiana tabacum plants highly susceptible to the pathogen. Previous results have shown that accumulation of acidic β-1,3-glucanases (PR-2's) following induction of SAR by P. tabacina may contribute to resistance to P. tabacina. We showed that up-regulation of the PR-2 gene, PR-2d, following stem inoculation with P. tabacina, is associated with SAR. Studies using plants transformed with GUS constructs containing the full length promoter from PR-2d or promoter deletions, provided evidence that a previously characterized regulatory element that is involved in response to salicylic acid (SA), may be involved in regulation of PR-2d following induction of SAR with P. tabacina. This work provides evidence that regulation of PR-2 genes during P. tabacina-induced SAR may be similar to regulation of these genes during infection of N-gene tobacco by TMV or following exogenous application of SA, and provides further support for the role of SA in regulation of genes during P. tabacina-induced SAR.  相似文献   
46.
Trypsin modulating oostatic factor (TMOF), a peptide hormone originally isolated from the ovaries of adult Aedes aegypti, is currently under commercial development as a new pesticide chemistry with a novel mode of action for the control of larval mosquitoes. The objective of the current research is to evaluate potential risks of the use of TMOF as an insecticide on non-target organisms. TMOF (YDPAP6) was degraded in vitro (as determined by HPLC and LC/MS) to DPAP6, PAP6, and then AP6 by leucine aminopeptidase, a pancreatic enzyme found in the digestive system of vertebrates. The rate of degradation of TMOF and PAP6 was significantly greater than that of DPAP6, while no metabolism of AP6 was found. TMOF technical insecticide was produced on a commercial scale by recombinant yeast (heat-killed before application). The technical TMOF when administered in a single dose by gavage to male and female mice at 2000 mg dry weight/kg body weight produced no negative effects as compared to controls up to 12 days after treatment. When male and female mallard ducks were treated by gavage with 1250 mg dry weight of technical TMOF/kg body weight each day for 5 days, again no toxic effects were noted through 35 days after the last treatment. TMOF technical insecticide was also applied to the shaved skin of male and female rabbits at the rate of 2000 mg/kg for 1-2 days, with no effect. The end point observations in these in vivo experiments were mortality; changes in growth rate, behavior, body structure, and color; and possible lesions observed during necropsy. Finally, Daphnia incubated with technical TMOF in rearing water at the level of 1.0 × 106 yeast cells/ml (10 mg/ml) also demonstrated no negative effects on mortality, growth, molting, time to first brood, and production of viable neonates. It appears from these studies that TMOF can be degraded by vertebrate digestive proteases and technical TMOF is not toxic to the non-target organisms examined.  相似文献   
47.
为提高真丝纤维织物的抗菌防皱性能,根据真丝纤维蛋白质主体的结构,研究了以硝酸铈铵(CAN)为引发剂,甲基丙烯酰氧乙基三甲基氯化铵(DMC)单体接枝真丝的影响因素,并对DMC接枝真丝后的回潮率、单丝强力和泛黄指数进行了研究,用红外光谱分析了接枝真丝的化学结构。当DMC浓度为06mol/L,CAN的质量分数为10%,pH=3,温度60℃保温120min时,接枝效果较好。接枝后回潮率改善,但泛黄指数有上升趋向,单丝强力也有所下降。红外光谱分析表明单体已接枝到真丝纤维上。  相似文献   
48.
通过体外和体内两种方法研究黄芩抗鸡大肠杆菌作用.通过体外抑菌作用测定黄芩水煎液对鸡大肠杆菌的最小抑菌浓度(MIC)为2.5g/ml;体内抑菌作用通过对7日龄雏鸡的攻毒与治疗试验来研究,体内治疗药物浓度5g/ml可使90%以上雏鸡获得保护,10g/ml可使100%雏鸡获得保护.以上说明黄芩可以对抗鸡大肠杆菌,可以防治鸡的大肠杆菌病.  相似文献   
49.
肉鸡大肠杆菌多价灭活蜂胶苗的研制   总被引:3,自引:0,他引:3  
从分离鉴定的49株大肠杆菌中筛选出5株致病力强、免疫原性好、具有优势血清型的大肠杆菌作为制苗菌株,经培养灭活后,以蜂胶为佐剂,研制出的肉鸡大肠杆菌多价灭活蜂胶疫苗,使用安全,免疫效果好。用该苗免疫后150d的保护率为100%,无不良反应。该苗4C下保存1年不失效。田间试验结果表明,该苗性能好,免疫后对肉仔鸡、肉种鸡的生产性能无不良影响,鸡群大肠杆菌病的死亡率明显下降。  相似文献   
50.
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