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排序方式: 共有198条查询结果,搜索用时 31 毫秒
1.
AIM:To investigate the effect of cholesterol metabolite 27-hydroxycholesterol (27-OHC) on the proliferation of lung cancer cells. METHODS:Human lung cancer A549 cells were treated with 27-OHC at different concentrations (0, 0.3125, 0.625, 1.25, 2.5, 5 and 10 μmol/L) for 24~48 h. The cell viability, cell cycle, cell prolife-ration, the intracellular cholesterol levels and cholesterol metabolism-related molecule expression were subsequently assessed by CCK-8 assay, flow cytometry, EdU staining, tissue total cholesterol detection kit, real-time PCR and Western blot. RESULTS:27-OHC decreased the viability of the A549 cells in a dose-and time-dependent manner (P<0.01) and inhibited the cell proliferation (P<0.05). The expression of typical liver X receptor (LXR) downstream target proteins including ATP-binding cassette transporter A1 (ABCA1), low-density lipoprotein receptor (LDLR), and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CR) were modulated, which promoted the efflux of intracellular cholesterol, and reduced cholesterol influx and de novo synthesis, resulting in decreased intracellular cholesterol levels and cell viability. Furthermore, the inhibitory effect of 27-OHC on A549 cell viability was significantly attenuated after the LXR pathway was partially blocked by 5 μmol/L GSK2033 treatment (P<0.05). CONCLUSION:27-OHC inhibits A549 cell prolife-ration via activation of LXR signaling pathway.  相似文献   
2.
AIM: To construct the prokaryotic expression system containing protein transduction domain (PTD) with heat shock protein 27 (HSP27) in order to prepare and purify the recombinant protein, and to verify whether the recombinant protein PTD-HSP27 has the ability to penetrate the human lens epithelial cell (HLEC) membrane and the rabbit cornea. METHODS: The plasmid pKYB-PTD-HSPB1-6His was constructed by the technique of overlap extension PCR. The plasmid was transformed and PTD-HSP27 was purified through nickel affinity chromatography column and identified by Western blotting. PTD-HSP27-6His was labeled with the fluorescein isothiocyanate (FITC). The penetrating ability of PTD-HSP27 into HLECs and rabbit cornea was tested. RESULTS: The recombinant PTD-HSP27 plasmid was successfully cloned and effectively expressed. The correctness of the recombinant protein PTD-HSP27 was demonstrated. Fluorescence microscopic examination showed that PTD-HSP27-FITC was internalized by HLECs. Fluorescent labeled PTD-HSP27 was then observed in the rabbit aqueous humor. CONCLUSION: The recombined gene PTD-HSPB1 was constructed by overlap extension PCR technique and the PTD-HSP27 fusion protein was prepared and purified by nickel affinity chromatography column. Using the technique of PTD-fusion protein, HSP27 was transduced into HLECs and passed through the cornea.  相似文献   
3.
Fsp27基因在动物脂肪代谢过程中发挥着重要的调控作用。为了研究Fsp27基因5'UTR区g.16767667位点G>A突变与绵羊尾脂沉积能力的关联性,以尾脂沉积能力极强的脂尾(臀)型绵羊品种阿勒泰羊(Ovis aries)为研究对象,采用PCR-SSCP及测序技术研究了该SNP位点不同基因型在阿勒泰羊群体中的分布,并通过比较不同基因型个体尾形数据的差异,评估其与阿勒泰羊尾脂沉积能力的关联性。结果表明,在阿勒泰羊群体中Fsp27基因5'UTR区g.16767667位点G>A突变可以检测到GG、AG和AA三种基因型,基因型频率分别47.2%、38.4%和14.4%;卡方检验结果表明该位点在阿勒泰羊群体中处于Hardy-Weinberg平衡状态(P>0.05)。通过250只不同基因型阿勒泰羊尾形数据对比发现,GG和AG基因型个体脂尾(臀)的长、宽和厚3项数据均显著高于AA基因型个体(P<0.05),GG基因型个体亦略高于AG基因型个体,但差异不显著(P>0.05),推断G等位基因有利于阿勒泰羊尾脂沉积。  相似文献   
4.
将BP人工神经网络(Artificiai neural network)技术与传统的正交试验方法相结合,提出一种新的试验分析和处理方法,利用神经网络特有的自学能力,对主要影响因素进行仿真优化,获得Bacillus velezensis Z-27菌株培养基组分,即玉米粉2.0%、豆饼粉1.5%、MnSO4· H2O 0.07%,起始pH为7.0、接种量为2.0%,应用优化得到的培养基组分进行验证试验,取得了较好的效果.  相似文献   
5.
试验结果表明,土壤烧施MGSC27后,能明显促进玉米和豆角的生长发育,增加玉米穗粒数和穗重;增加豆角单株结荚数、荚长和鲜荚重。增产效果显著,其中玉米增产10.6%,豆角增产9.9%。  相似文献   
6.
Abstract

The phytotoxicity of aluminum (Al) in relation to preculture with phosphates was examined in the rice cultivar Arkansas fortuna. In plants precultured with phosphates, Al did not inhibit shoot growth, while Al retarded shoot growth in plants precultured without phosphates. In contrast, Al inhibited root elongation, irrespective of the presence of phosphates in the preculture solution. A large proportion of the Al in roots was in unknown, insoluble forms. In phosphate‐precultured plants, Al deposition was slightly increased, presumably due to the formation of aluminum phosphates in the roots, and phosphorus levels in shoots were markedly increased. Binding with phosphates may ameliorate the toxicity of Al when it enters the shoots and account for the uninhibited shoot growth in the presence of Al in plants precultured with phosphates.  相似文献   
7.
陶侠林 《安徽农业科学》2006,34(12):2688-2688
根据多年油菜制种经验和皖油27号父母本生育特点,科学总结了制种技术。  相似文献   
8.
目的:探讨HSP27、p14^ARF和caspase-3蛋白在大肠癌中的表达及其与大肠癌I临床病理特征的关系。方法:利用sP法检测大肠癌48例和大肠腺瘤10例以及正常大肠黏膜组织15例中HSP27、p14^ARF和caspase-3蛋白的表达。结果:大肠癌组织中HSP27、p14^ARF和caspase-3蛋白阳性表达率分别为79.2%、58.4%和66.7%,大肠腺瘤组织中分别为40.0%、70.0%和100.0%,正常大肠黏膜组织中分别为33.3%、80.0%和93.3%。p14^ARF和caspase-3蛋白的表达在高、中分化癌组的表达率分别为64.1%、74.4%,明显高于低分化组22.2%、33.3%(Pd0.05)。结论:HSP27、p14^ARF和caspase-3与大肠癌的发生有关,可作为大肠癌临床评价肿瘤生物学行为的指标。  相似文献   
9.
玉米新品种豫玉27群体生理指标的研究   总被引:11,自引:0,他引:11  
对豫玉27群体生理指标进行了研究,结果表明豫玉27叶片上冲,叶向值大,株型紧凑,群体内光分布较合理。叶面积系数和光合势稳定期长,衰减慢,叶片净同化率高,后期灌浆持续时间长,强度高,全株地上部于物质积累呈“S”型曲线,从吐丝授粉开始到授粉内25d干物质积累为最终生物产量的50.9%~53.4%。适宜种植密度为63000~69000株/hm~2。  相似文献   
10.
棉花优良品种中棉所27直接胚胎发生与植株再生   总被引:3,自引:0,他引:3  
选用我国难培养基因型优良棉花品种中棉所27进行组织培养,研究了该品种体细胞胚胎发生与植株再生能力。该品种体细胞胚胎发生有2种情况:一是由外植体直接诱导获得胚性愈伤组织并形成不同发育时期的胚状体;二是先诱导获得非胚性愈伤组织,再经多次继代培养,获得胚胎发生。不同激素及其组合和浓度配比是影响中棉所27直接诱导获得胚性愈伤组织及体细胞胚胎发生的直接因素。另外,饥饿培养及继代周期对胚胎发生也有重要影响。0.1mg/LKT和0.1mg/LIAA组合、0.1mg/LKT和0.1mg/LZT组合、0.1mg/LZT单独使用,在饥饿条件下培养,均能直接高效诱导获得大量胚性愈伤组织,并有短期内形成不同发育时期的胚状体。胚状体在不含任何激素的MS B5培养基上培养有利于植株再生,并降低畸形苗形成率。另外,还发现不同培养基对中棉所27胚性愈伤组织增殖、体细胞胚形成和萌发的影响不同。  相似文献   
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