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41.
为快速检测猪繁殖与呼吸综合征病毒,应用抗猪繁殖与呼吸综合征病毒单克隆抗体PRRSV-3D10株和4H11株分别作为胶体金标记物和诊断抗体,羊抗鼠IgG作为质控线,制备胶体金免疫层析抗原检测试纸。该试纸卡具有良好的特异性、敏感性、重复性和稳定性,与PCR方法对比总符合率为93.3%。研究显示,本试纸卡能够快速、准确检测猪繁殖与呼吸综合征病毒,可为临床诊断提供参考。  相似文献   
42.
在玉米高产栽培过程中,由于种植密度加大、倒伏、秃尖等现象常常出现,严重制约了玉米产量的提高。本试验研究了玉黄金不同量级、不同施用时期对玉米化控作用的影响。结果表明:玉黄金属于缓慢抑制型调节剂,在玉米8展叶时用玉黄金300 mL/hm2、兑水225 kg 喷施,株高可降低18.8 cm、穗位降低22.0 cm,茎秆增粗,抗倒能力提高,提早成熟2 d,增产8.51%,效果最好。  相似文献   
43.
条浒苔蛋白核超微结构和Rubisco及其活化酶分子定位   总被引:3,自引:0,他引:3  
何培民 《水产学报》2004,28(3):255-260
研究了条浒苔蛋白核超微结构及其Rubisco和Rubisco活化酶金相免疫分子定位。超微结构显示,条浒苔细胞具有形态及组成相同的1~2个蛋白核,每个蛋白核被淀粉鞘所包围。蛋白核中央均有1条由1个类囊体构成的纵向孔道,并有时局部特别膨大。纵向孔道两端与叶绿体基质相连接。小球藻Rubisco抗体对条浒苔Rubisco的Western印迹图谱显示仅为1条带,其位置与SDS-PAGE电泳图谱上的主带相对应,分子量大约为55kD。金相免疫分子定位的结果显示,条浒苔Rubisco金标颗粒主要分布于叶绿体的蛋白核(71.86%)和淀粉鞘(27.94%)部位中,按面积密度计算二者总和占99.8%,极少分布在叶绿体类囊体和基质中(0.2%)。Rubisco活化酶分子定位也显示其主要分布于蛋白核和淀粉鞘中。这些结果均表明条浒苔蛋白核(及淀粉鞘)与单细胞绿藻的蛋白核相同,具有光合作用功能。条浒苔Rubisco初始活性和总活性的测定结果表明,其活化率较高,高达77.62%。  相似文献   
44.
There is an increasing body of evidence of the positive impact of several marine lipids on human health. These compounds, which include ω-3 polyunsaturated fatty acids, have been shown to improve blood lipid profiles and exert anti-inflammatory and cardioprotective effects. The high instability of these compounds to oxidative deterioration and their hydrophobicity have a drastic impact in their pharmacokinetics. Thus, the bioavailability of these compounds may be affected, resulting in their inability to reach the target sites at effective concentrations. In this regard; micro/nanoparticles can offer a wide range of solutions that can prevent the degradation of targeted molecules, increase their absorption, uptake and bioavailability. In this work we will present the options currently available concerning micro- and nanodelivery systems for marine lipids; with emphasis on micro/nanoparticles; such as micro/nanocapsules and emulsions. A wide range of bottom-up approaches using casein, chitosan, cyclodextrins, among others; will be discussed.  相似文献   
45.
为探究茶多酚(Tea Polyphenols, TPs)对辛烯基琥珀酸酐(Octenyl Succinic Anhydride, OSA)酯化淀粉纳米颗粒(Starch Nanoparticles,SNPs)及其稳定的Pickering乳液性质的影响,该研究在制备OSA-SNPs的过程中添加TPs,研究TPs对OSA-SNPs的理化性质和乳化性能的影响。结果发现,添加TPs使OSA-SNPs的平均粒径增加、表面Zeta电位绝对值下降、接触角减小(P<0.05)。通过傅立叶红外光谱扫描发现,TPs与OSA-SNPs之间存在氢键和疏水相互作用。在TP-OSA-SNPs稳定的乳液中,增加TP-OSA-SNPs的质量浓度(从0.5 g/mL至2.0 g/mL),乳滴平均直径明显减小(P<0.05);当TP-OSA-SNPs的质量浓度增加至2 g/mL时,乳液形成了油滴紧密堆积的界面结构,能够抑制油滴迁移。通过加速氧化试验发现,与OSA-SNPs相比,TP-OSA-SNPs稳定的乳液中氢过氧化物值(Peroxide Value, POV)相对较低(P<0.05),说明TP-OSA-SNPs具有延缓乳液中油脂氧化的作用。结果表明,这种新型具有抗氧化功能的食品级颗粒乳化剂,对构筑淀粉基Pickering乳液载体具有潜在价值。  相似文献   
46.
吴蝉 《安徽农业科学》2014,(2):398-400,402
为了有效地评估纳米粒子对植物潜在的生物毒性,选取玉米和氧化铁纳米粒子为研究对象,探讨氧化铁纳米粒子(nailo-Fe2O3)对玉米生理效应的影响。同时,测定抗氧化酶体系的酶活性和丙二醛(MDA)含量,结果表明当受到氧化铁纳米粒子胁迫时,玉米会发生氧化应激反应,但这会激发玉米本身的保护机制,导致整个机体的抗氧化预防能力增强,使得机体的超氧阴离子自由基含量降低,减少对机体的损害。同时,通过玉米根的荧光切片和透射电镜切片,可以得出氧化铁纳米粒子从上皮层运输到皮质层主要是通过质外体途径.并且能够进入玉米细胞中、、这些为评估纳米粒子对植物的影响奠定基础。  相似文献   
47.
Aeromonas salmonicida is the causative agent of furunculosis, a disease that affects both salmonid and non‐salmonid fish. Detection of A. salmonicida can be labour intensive and time consuming because of the difficulties in distinguishing the bacterium from other species given the wide variety of existing biochemical profiles and the slow growth characteristics which allow other organisms to overgrow the A. salmonicida. Herein, we report the development of a specific immunoassay using gold‐conjugated polyclonal antibodies for the rapid detection of A. salmonicida in fish tissues. Monodispersible 13‐nm gold nanoparticles were coated with polyclonal antibodies specific to A. salmonicida. Reddish purple agglutination of gold particles indicated the presence of A. salmonicida in samples. Positive reactions were detected visually with the naked eye. No agglutination was observed when A. salmonicida antibodycoated gold nanoparticles were tested with other common bacterial fish pathogens, thereby verifying the specificity of the assay. The assay could detect A. salmonicida in fish tissues down to 1 × 104 CFU mL?1, and results were obtained within 45 min. The antibody‐coated gold nanoparticles were stable for at least 2 months at 4°C. The immunoassay using antibody‐coated gold nanoparticles represents a promising tool for the rapid and specific detection of A. salmonicida in fish tissues.  相似文献   
48.
Silver nanoparticles (AgNP) are used in a broad range of consumer products and industrial applications. During the regular product life cycle and disposal, AgNP are continuously released into the environment. Hence, the aim of this study was to investigate the potential ecotoxicological effects of AgNP exposure on amoebae. The Acanthamoeba castellanii ATCC 30234 strain and environmental isolate Acanthamoeba strain C5/2, which are both affiliated with genotype T4, were chosen as representatives of ecologically important soil protozoan organisms. The amoebae were exposed to citrate‐stabilized AgNP (30 and 70 nm in size) for 24 h and 96 h at concentrations ranging from 600 µg L−1 to 20 mg L−1. A newly adopted cell culture based microscopic assay was applied to assess the adherence ability of the amoeba trophozoites. The general metabolic activity of Acanthamoeba was determined to be a second independent endpoint by means of intracellular reduction of the redox dye AlamarBlue®. The fate of AgNP within the amoebae and test solutions was visualized by light‐ and transmission electron microscopy (TEM). Both Acanthamoeba strains showed a significant dose‐dependent decrease of adherence ability (p  < 0.04) and metabolic activity (p < 0.01) after 96 h of AgNP exposure. The environmental Acanthamoeba strain C5/2 lost both its adherence ability and metabolic activity at lower AgNP concentrations than the type strain, indicating a higher sensitivity to ionic silver. This was confirmed by the application of AgNO3, provoking a higher effect level in strain C5/2. AgNP was visualized intracellularly by transmission electron microscopy within the cytoplasm of Acanthamoeba . This is the first report to show the ecotoxicological effects of short‐term AgNP exposure on the soil protist Acanthamoeba , causing both changes in the adherence ability and metabolic activity of this amoeba. This combined approach may be a powerful tool in the future for predicting potential harmful ecotoxicological effects of AgNP exposure using soil protozoans.  相似文献   
49.
近几届奥运会,我国竞技体育竞技实力格局发生了变化。主要采用数理统计法和逻辑分析法,从近几届我国代表团的金牌分布演变、奖牌分布演变、优势与潜优势项目演变等方面进行了分析。研究结果表明:1金牌分布点逐渐增加;2奖牌分布面更广;3游泳成为金牌和奖牌的新增长点,已经成为重点优势发展项目;4我国竞技体育整体竞技水平明显提高,优势项目和潜优势项目结构发生了调整。最后,结合我国竞技体育竞技实力格局嬗变现实情况,提出了几点思考。  相似文献   
50.
鸡传染性法氏囊病快速诊断试纸的研制   总被引:3,自引:0,他引:3  
本文简述用胶体金免疫层析技术,构建鸡传染性法氏囊病快速诊断试纸。试纸主要由测试端、显色区和手柄端3部分构成,能在很短的时间内完成对鸡传染性法氏囊病的诊断,且无需任何仪器设备,具有简便、快速、敏感、特异的特点。  相似文献   
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