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Search Results: 1 - 10 of 166839 matches for " 徐文娣 "
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邻苯二甲醛荧光检测蛋白质的研究
,松林,张仁斌
分析化学 , 1987,
Abstract: 本文考察了邻苯二甲醛荧光检测蛋白质的方法中各种因素的影响,测定了其检测的线性范围,并对其灵敏度与紫外检测法进行了比较。由于此法具有反应快、检测灵敏度较高和线性范围较宽等优点,可考虑用为柱后衍生的高效液相色谱法以检测分离的蛋白质。
利用rnai逆转录病毒载体系统对人朊病毒蛋白表达的稳定抑制
婧?,,王娟?,杨怀义?
生物工程学报 , 2009,
Abstract: 朊病毒是引起可传染的致死性海绵状脑病的致病因子,细胞中正常的朊病毒蛋白(prpc)在该疾病病程发展中起着必不可少的作用。同时,prpc已被证明在胃癌、乳腺癌等癌症中发挥着保护癌细胞的作用。根据人源prpc(huprpc)cdna序列,本研究设计了4种19nt的sirna,将其构建成rnai逆转录病毒载体系统,进行了其对huprpc表达的抑制效应的分析,从中获得了能高效稳定抑制huprpc表达的3种靶向序列,其中si626(5¢-ggttgagcagatgtgtatc-3¢)的抑制效果最为明显,其抑制效率可达85%以上。随后,利用筛选出的si292和si626的稳定干扰细胞系进行了细胞浸润性实验,结果发现,prpc干扰细胞系细胞浸润能力显著下降。这为进一步研究朊病毒疾病的基因治疗、以prpc为靶标进行prpc相关癌症的辅助治疗研究奠定了一定的基础。
花棒生理生态研究及其展望
Research of Huabang(Hedysarum scoparium)Ecophysiology and Its Perspectives

金红宇,,陈国雄
- , 2018, DOI: 10.7606/j.issn.1004-1389.2018.11.002
Abstract: 花棒(Hedysarum scoparium Fish. Et Mey.),又名细枝岩黄耆,沙漠中豆科大灌木,固沙先锋植物,种子可食,嫩枝叶是优良饲草,对沙区生态建设与绿色发展具有重要意义。生理生态学研究揭示了花棒对沙漠环境的适应性机理,为其固沙造林和引种驯化提供了理论依据。近年来,花棒生理生态学研究取得了较大进展,在种子萌发方面,探明了果荚对“部分休眠”的物理限制作用、萌发所需环境条件、飞播及育苗的最佳时间;在生长发育发面,揭示了生长发育规律、繁殖策略、根际微生物及根瘤菌的促生作用;在耐逆性方面,发现了耐风蚀沙埋独特的克隆生长构型、C4途径生化亚型、耐旱光合生理及水分关系;在固沙造林方面,根据其生理生态学基础,提出了不同区域的合理布局和适宜密度,建立了固沙造林的成功案例。然而,花棒造林还存在一些问题,如耐盐性不够强、有病虫危害、易烂根等。针对这些问题,需要开展相应的生理机制和遗传育种研究,建立种质资源库,培育耐盐抗病虫害品种。花棒生理生态学进一步研究:比较不同沙区花棒的代谢组、转录组、基因组等组学特征,结合地理学和分子遗传学分析,揭示花棒在我国沙漠的进化历程。此外,花棒在沙区畜牧业、城镇园林绿化、食品与食用油等方面的开发利用研究亦具有广阔前景。
Huabang(Hedysarum scoparium Fish. Et Mey.)is a large leguminous shrub in sandy desert in China. It is a sand-fixation pioneer with edible seeds and newly growing shoots used for forage.H.scoparium is of great significance for ecological construction and green development in desert region. Ecophysiological research has revealed the adaptation mechanisms of huabang to sandy desert environment,which provides theoretical base for sand-fixation afforestation and domestication. Recently,huabang ecophysiological research has achieved great progresses.In seed germination,the physical limitation of pod on partial dormancy,the environmental conditions require for germination,and the time for aerial seeding and seedling nursery are verified. In growth and development,the characteristics of growth and development,reproductive strategies,and the growth promotion of rhizosphere microorganism and nodule bacteria are revealed. In stress tolerance,specific clone-growth patterns against sand erosion and bury,biochemical subtypes of C4 pathway,and drought-tolerance photosynthesis physiology and water relations are discovered. In sand-fixation afforestation,based on ecophysiological research,rational pattern and suitable density are proposed; some successful cases of sand-fixation afforestation are established. However,some problems remains for the sand-fixation afforestation,such as salt stress,insect and diseases damage,and root rot. To solve these problems,research of its physiological mechanisms and breeding are required; the establishment of huabang genetic bank and varieties with salt and biotic tolerance are needed. For further ecophysiological researches,the comparisons of metabolome,transcriptome,and genome of huabang from different sandy regions should be conducted; the evolution process of huabang in Chinese sandy desert should be revealed by the combination of ecophysiology with geography and molecular genetics. In addition,huabang has a great potential in developmental research on animal husbandry in sandy
Response to aluminum toxicity of four common weeds roots and border cells
四种常见杂草根系及根边缘细胞对铝胁迫的响应

周楠,刘鹏,,汪晔,孙芳华,
生态学报 , 2009,
Abstract: Four herbaceous plants, gramineae weeds (Digitaria ciliaris, Echinochloa crusgali) and composite weeds (Eclipta prostrata, Crassocephalum crepidioides) distributed in the red soils of the South China, were used to examine activity of root border cells, root relative elongation, levels of aluminum, proline, malondialdehyde (MDA), and membrane permeability (MP) in the Al-treated roots. It was found that activity of root border cells was significantly decreased with increasing Al3+ concentrations or treatment time in these four weeds. The decreasing magnitude was higher in composite weeds than in gramineae weeds, while the contents of aluminum, proline and MDA, and membrane permeability were increased in the roots. Further analysis showed that root growth was more markedly inhibited by Al in Eclipta prostrata and Crassocephalum crepidioides than in Digitaria ciliaris and Echinochloa crusgali under the same conditions. The contents of aluminum, proline and MDA, and membrane permeability in these four weeds roots reached a maximum at 1000 mg?L-1 Al3+ concentrations, while the increase in Digitaria ciliaris and Echinochloa crusgali were less than in Eclipta prostrata and Crassocephalum crepidioides. No significant increase was observed on contents of proline and MDA in gramineae weeds roots among the different exterior Al3+ levels (P>0.05). These findings suggested that the damage levels of aluminum to these four weeds were enhanced with increasing Al concentrations and exposure time; However, the relatively higher activity of the root border cells, longer root relative elongation, lower levels of aluminum, proline, MDA and MP improved the tolerance to Al stress in Digitaria ciliaris and Echinochloa crusgali. Gramineae weeds(Digitaria ciliaris, Echinochloa crusgali) were more resistant to Al toxicity than composite weeds(Eclipta prostrata, Crassocephalum crepidioides).
Effect of Cu stress on nitrogen metabolism of Nicotiana labacum L. seedling
铜胁迫对烟草幼苗氮代谢的影响

张艳英,周楠,刘鹏,,,蔡妙珍
生态学报 , 2009,
Abstract: Under solution culture, used Cu-tolerant cultivar 89112 and sensitive cultivar Shuang-70 of Nicotiana labacum L. as plant material, five Cu levels (0, 0.5, 1, 5, and 10 mg?L- 1) were applied to study the effects of copper on nitrogen metabolism. The results showed that with the increase of Cu concentration, the contents of NO-3 -N in two Nicotiana tabacum cultivars were increased firstly and then decreased, and the NO-3 -N contents in 89112 were higher than in Shuang-70. The negative effects of Cu on the assimilation of NO-3 -N were increased with the treated length., The activities of GS and GOGAT were increased firstly and then were inhibited by the increased Cu. Then, as the treated length prolonged, the inhibitory effects were increased. In constrast to Shuang-70, the enzyme activities were higher in 89112, implicating that the 89112 is more tolerant to high Cu stress. At low Cu lever, activity of glutamate-pyruvate transaminase (GPT) was increased, and content of the free amino acids was reduced. The decline of the free amino acid contents in Shuang-70 was more rapidly. Compared with the control, protein content was increased by Cu stress. In short, it is indicated that Cu stress may enhance nitrogen transformation metabolism in Nicotiana tabacum L. seedling.
中华管鞭虾(Solenocera crassicornis)蛋白酶的纯化及其生化特性研究
,薛长湖,大伦,何雄,潘云,陈士国
海洋与湖沼 , 2006,
Abstract: 采用Tris-HCl缓冲液(50mmol/L,pH7.5)抽提、Q-sepharose F.F.阴离子交换层析、Sephacryl S-300凝胶过滤层析、SDS-PAGE等方法,进行中华管鞭虾虾头蛋白酶的分离纯化、酶学性质及其动力学特性的研究。结果表明,中华管鞭虾虾头蛋白酶粗提物经层析后,得到聚丙烯酰胺凝胶电泳纯的一酶组分。该蛋白酶的比活力从359.39U/mg增加到8277.83U/mg,提高了23.03倍,回收率达37.69%,SDS-PAGE显示该蛋白酶只含一条谱带,相对分子量为24.50kDa。以偶氮酪蛋白作为底物,该酶的米氏常数Km值为0.28mg/ml,最适温度为55℃,最适pH为7.5;蛋白酶在60℃以下比较稳定,放置1h后活性仍保持在60%以上,而在60℃以上时蛋白酶活性急剧下降,80℃放置1h后,酶活性只残留21.32%。10mmol/L Cu2+、Zn2+和EDTA对该蛋白酶有较强的抑制作用,抑制率分别约为97%、96%和55%,10mmol/LMg2+能显著促进蛋白酶活性,而10mmol/L Fe2+、Ba2+、Ca2+对蛋白酶活性的影响不大。推测中华管鞭虾蛋白酶可能为一种金属蛋白酶。
海洋放线菌XS904分类鉴定及其发酵液抑菌活性的研究
,楼乔明,大伦,孙爱飞,潘云
海洋与湖沼 , 2008,
Abstract: 采用形态观察、培养特征、生理生化鉴定以及16S rDNA序列分析方法,对从宁波海域滩涂泥样中筛选到的一株放线菌XS904进行分类鉴定,同时对XS904菌株发酵液的抑菌活性和抑菌物质的理化性质进行了研究。结果表明,XS904菌株为链霉菌属灰浅红链霉菌(Streptomyces griseorubens)的变种;经液体培养,XS904菌株发酵液对革兰氏阳性细菌有显著的抑菌活性,对金黄色葡萄球菌的最小抑制浓度为0.78%;pH纸色谱和捷克八溶剂系统纸层析结果显示发酵液中的抑菌活性物质为一类中等极性的碱性抗生素,易溶于三氯甲烷,对温度较敏感,在酸性和中性条件下稳定。
直流射频等离子体增强化学气相沉积类金刚石碳薄膜的结构及摩擦学性能研究
李红轩,,陈建敏,周惠,刘惠
摩擦学学报 , 2004,
Abstract: 利用直流射频等离子增强化学气相沉积技术在单晶硅表面制备了类金刚石碳薄膜.采用Raman光谱、红外光谱、x射线光电子能谱和原子力显微镜等研究了薄膜的微观结构和表面形貌,在UMT-2MT型摩擦磨损试验机上考察了薄膜在不同载荷与滑动速度下的摩擦学性能。结果表明:所制备的类金刚石碳薄膜具有典型的类金刚石结构特征,薄膜均匀、致密,表面粗糙度小,硬度较高;薄膜与Si3N4陶瓷球对摩时显示出良好的抗磨减摩性能;随着试验载荷与滑动速度的提高,薄膜的摩擦系数降低,耐磨寿命降低;薄膜的减摩抗磨性能同其在Si3N4陶瓷球偶件磨损表面形成的转移膜相关。
摩擦偶件材料对非晶含氢碳薄膜摩擦学性能的影响
李红轩,,郝俊英,陈建敏,周惠,刘惠
摩擦学学报 , 2004,
Abstract: 利用等离子体增强化学气相沉积技术在单晶硅基底上制备了非晶含氢碳薄膜;采用Raman光谱仪、红外光谱仪和原子力显微镜等研究了碳膜的微观结构和表面形貌;采用UMT-2MT型摩擦磨损试验机考察了摩擦偶件材料对碳膜摩擦学性能的影响,并探讨了其磨损机制.结果表明:所制备的非晶含氢碳膜均匀、致密,硬度较高;当碳膜同高硬度陶瓷材料配副时,其摩擦系数低而稳定,薄膜呈现轻微擦伤和剥落磨损特征;当碳膜同低硬度的金属材料配副时,其摩擦系数高且不稳定,薄膜呈现严重粘着和磨粒磨损特征.薄膜的摩擦磨损行为同薄膜和摩擦偶件之间的相互转移有关.
黄瓜根边缘细胞生物学特性及其对铝的响应
周楠,,刘鹏,,蔡妙珍
园艺学报 , 2006,
Abstract: 以黄瓜为试验材料,研究了黄瓜根边缘细胞的生物学特性及其对铝毒的响应。试验结果表明,在黄瓜种子萌发过程中,根边缘细胞有很高的活性。当根长度在25mm,根边缘细胞数目达到最高值5480个,根伸长到10mm时,pme(果胶甲基酯酶)相对活性达到最高值,然后随着根的伸长,pme相对活性逐渐下降。在铝处理的条件下,黄瓜根长及边缘细胞的存活率会随着铝液浓度的升高依次递减,说明铝毒对根的发育有明显的抑制作用及危害,而根冠的pme活性却有所提高,说明了pme与植物铝毒胁迫之间存在着相关性。铝毒条件下边缘细胞pme活性的提高,使细胞壁的果胶去甲基化,增加了al3+的结合位点,从而避免铝更多地进入细胞内,造成对植物的毒害。
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