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31.
FGF4已经被证明是癌基因,它涉及肿瘤的生长和转移,为了解FGF4的表达与肿瘤微环境的关系。我们利用FGF4抗体通过免疫组化对一名肺癌患者癌旁,癌组织,癌组织小鼠移植瘤,二次移植瘤以及原代培养的细胞爬片进行FGF4检测,探究其表达差异。通过对比癌组织与对照组(癌旁组织),FGF4在癌巢中高表达;同样,移植瘤与二次移植瘤的癌巢中与癌旁组织比较,FGF4表达相对较高;但是将癌组织进行原代培养后,免疫组化检测细胞爬片FGF4,发现仅有5%±0.21%的肿瘤细胞表达FGF4,对照蛋白Cytokine作为肿瘤标记物,则在100%的肿瘤细胞中表达。研究提示免疫组化检测到FGF4在体内和体外表达不同,提示肿瘤细胞FGF4的表达与肿瘤微环境调控密切相关,肿瘤微环境对肿瘤细胞的FGF4的调控有着重要作用。 相似文献
32.
The assay was aimed to explore the biological characteristics of bone morphogenetic protein 4 (BMP4) of sheep,NCBI,DNAMAN DNAStar,TMHMM Server v.2.0,PsortⅡ,SignalP various bioinformatical softwares were used to speculate the physical and chemical properties,hydrophobic property,phosphorylation site,conservative structure domain,protein secondary structure of BMP4 protein.Also,the three-dimensional structure was forecasted with the SWISS-MODEL Workspace software.The results indicated that the BMP4 of sheep had high homologies with the BMP4 of various species.The encoded protein was a hydrophilic protein which was unstable.There was no transmembrane regions and it was likely to be located in the nucleus.What was more,there was signal peptide and eighteen phosphorylation sites.Through the forecast of functional domains,the protein had two functional domains,including the transforming growth factor-beta (TGF-beta) superfamily and TGF-beta propeptide superfamily.The result was consistent with the function of BMP4 gene family,it also demonstrated that BMP4 was a growth factor and it had the function of signal transduction.The amino acid homology between the predicted 3D structure of protein and template 3bmp.1.A was 88.29%.The bioinformatics analysis of BMP4 gene could provide reference for the further study in practice. 相似文献
33.
探讨蜂王浆对尾静脉注射4T1细胞小鼠的抗氧化和免疫力的影响.将4T1细胞或其与蜂王浆的混合物通过尾静脉注射入小鼠体内,ELISA法检测蜂王浆对小鼠血清、肝脏和肾脏中与抗氧化能力相关的指标及血清中和免疫力相关细胞因子水平的影响.结果表明,和模型对照组相比,蜂王浆(50、100 mg·mL~(-1))可以显著提高小鼠血清内T-AOC、IFN-α(P0.05)水平,降低IL-4的水平(P0.05);蜂王浆剂量为50 mg·m L~(-1)时,IFN-γ的含量显著增加(P0.05).蜂王浆(100 mg·mL~(-1))显著提高肾脏中T-AOC的水平(P0.05).可见,蜂王浆可以改善尾静脉注射4T1细胞小鼠的抗氧化能力和免疫力. 相似文献
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The environmental impact of crop production is mainly related to fossil fuels consumption and to fertilisers application. Emissions arising from the spreading of organic and mineral fertilisers are important contributors for impact categories such as eutrophication and acidification. The choice of the fertilisers and of the spreading techniques as well as the crop residues management can deeply affect the environmental impact related to crop cultivation.In this study, seven scenarios describing fertilising schemes characterised by different organic and mineral fertilisers and by different mechanisation were compared. The aim is to evaluate, using the Life Cycle Assessment (LCA) method, how the environmental performances of grain maize production were affected by these different fertilisers schemes. The study was carried out considering a cradle to farm gate perspective and 1 t grain maize was selected as functional unit. Inventory data were collected on a farm located in Po Valley (Northern Italy) during year 2013 and were processed using the composite method recommended by the International Reference Life Cycle Data System (ILCD). The compared scenarios involved organic and mineral fertiliser distribution and were: pig slurry incorporation after >3 days after spreading (BS), fast pig slurry incorporation within 2 h from spreading (AS1), direct soil injection of pig slurry (AS2), pig slurry incorporation (after >3 days) with straw collection (AS3), digestate spreading instead of pig slurry (after >3 days) (AS4), only mineral fertilisers (i.e. urea and superphosphate) distribution (AS5) and only mineral fertilisers (i.e. calcium ammonium nitrate and superphosphate) distribution (AS6).The results were not univocal, since climate and soil conditions as well as physical and chemical fertiliser characteristics differently affected the environmental load, especially for particulate matter formation, terrestrial acidification and terrestrial eutrophication impact categories. AS1 and AS2 showed the most beneficial results for these impact categories (between ↙67% and ↙73% respect to worst scenario). AS6, on the opposite, showed the highest environmental impact for those impact categories mainly affected by energy and fossil fuel consumption (climate change, ozone depletion, human toxicity with carcinogenic effect, particulate matter, freshwater eutrophication, freshwater ecotoxicity and mineral, fossil and renewable resources depletion), categories on which AS3 and AS4 were the best solutions. AS3 was the most impacting for terrestrial acidification and eutrophicationA sensitivity analysis was carried out varying grain maize yield (mostly affected: marine eutrophication) and ammonia volatilisation losses due to organic fertilisers (mainly affected: terrestrial acidification and eutrophication).The achieved results can be useful for the development of ⬓spreading rules⬽ that drive the application of organic fertilisers in agricultural areas where there is an intense livestock activity. 相似文献
36.
欧美杂交杨Pnd-LRR3基因克隆及其抗锈菌侵染表达 总被引:1,自引:0,他引:1
为深入探究欧美杂交杨(Populus nigra×P.deltoides)感病的分子机理,以及抗病基因在发病过程中所起的作用,克隆了欧美杂交杨LRR3蛋白编码基因Pnd-LRR3。对Pnd-LRR3基因进行了生物信息学分析,并对其在抗锈菌过程中的功能进行了研究。Q-PCR结果显示,强致病性的落叶松-杨栅锈菌(Melampsora larici-populina)E4菌株接种6 h,Pnd-LRR3基因表达量上调增幅较大,168 h为显著下调。说明Pnd-LRR3基因在E4侵染过程中起到一定抗性作用,但最终无法阻止锈菌的侵染。 相似文献
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38.
池永亮 《林业机械与木工设备》2015,(3):19-21,26
分别采用GB 18580标准中的干燥器法和穿孔萃取法检测中密度纤维板的甲醛释放量,并根据两种方法检测出的结果分析其相关性。结果表明,两种检测方法呈显著线性相关。 相似文献
39.
Perennial rhizomatous grasses (PRGs) tend to have a high yield combined with a low environmental impact. Cultivation in marginal or poorly cultivated land is recommended in order not to compromise food security and to overcome land use controversies. However, the environmental impacts of using different types of soil are still unclear. We thus assessed the environmental impact of two giant reed (GR) systems cultivated in a fertile soil (FS) and in a marginal soil (MS) through a cradle-to-plant gate LCA. We analyzed energy balance, GHG emissions (including LUC, not including iLUC), and the main impacts on air, water and soil quality. In both systems the annualized soil carbon sequestration was more than twofold the total GHG emitted, equal to −6464 kg CO2eq ha−1 in FS and −5757 kg CO2eq ha−1 in MS. Overall, soil characteristics affected not only GR yield level, but also its environmental impact, which seems to be higher in the MS system both on a hectare and tonne basis. The production of GR biomass in marginal soil could thus lead to higher environmental impacts and a more extensive land requirement. 相似文献
40.