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应用甲基化敏感扩增多态性(MSAP)技术对6头长白公猪和50头蓝塘母猪及5头长白×蓝塘杂交F1代3个群体基因组DNA胞嘧啶甲基化位点进行检测,旨在克隆和分析父母代猪及其杂种F1代之间基因组DNA共同甲基化片段和差异片段,并找到其同源基因.结果显示,从MSAP条带中分离、克隆得到18条3个群体共同的甲基化片段、10条母代独有的甲基化片段和9条杂交一代独有的甲基化片段,其中有1条3个群体共有的甲基化片段通过EST拼接和电子延伸后在NCBI数据库中找到同源基因,即猪类酪氨酸蛋白激酶Lyn基因(GeneID:LOC100152890,序列号:XM_001926250).结果表明,长蓝杂交F1代与其父母代之间的基因组甲基化存在异同,为通过MSAP技术克隆猪基因组DNA甲基化片段及寻找其对应的甲基化基因提供可能,也会为将来研究这些甲基化基因表达调控机制奠定基础.  相似文献   
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以自然生长的典型红砂(Reaumuria songarica(Pall.)Maxim.)群落中的幼苗为研究对象,以自然降雨为对照,设定降雨量减少30%(W~-)、不变(W)和增加30%(W~+)3个降雨量水平,2个降雨时间间隔即自然降雨时间(T)、延长降雨间隔时间至1.5倍(T~+)),研究降雨格局变化对红砂幼苗根系生长和生物量分配的影响。结果表明:(1)同一降雨量条件下,降雨间隔延长促进了红砂幼苗主根的伸长生长、增加了根表面积,增大了根冠比,有利于红砂幼苗根系生长。(2)降雨量较少的条件下(W~-、W),延长降雨间隔促使红砂幼苗地下、地上及总生物量累积;而降雨量较多(W~+)条件下,延长降雨间隔使各部分生物量有所降低,但差异不显著。(3)在自然降雨间隔条件下,降雨量的增加使红砂幼苗的总生物量和主根长呈增加的变化趋势,对其生长起到促进作用。研究认为,降雨格局的变化会明显影响自然生长的红砂群落中幼苗的生长和生物量分配。  相似文献   
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Wang  Te  Jiang  Zhengzhong  Dong  Wenbo  Liang  Xiaoya  Zhang  Linghua  Zhu  Yimin 《Annals of microbiology》2019,69(13):1425-1433
At present, the nitrogen (N) removal efficiency of the microbial treatment in the high-salinity nitrogenous wastewaters is relatively low. Study on the N removal behavior and properties of moderately halophilic bacteria Halomonas under high salinity is of great significance for the microbial treatment of high-salinity nitrogenous wastewater. The response mechanism of Halomonas sp. B01 to high osmotic pressure stress was investigated by measuring the compatible solute ectoine concentration and superoxide dismutase (SOD) activity. The salt tolerance during growth and N removal of the strain was evaluated by measuring the activities of growth-related and N removal–related enzymes and the mRNA expression abundance of ammonia monooxygenase-encoding gene (amoA). The process of simultaneous heterotrophic nitrification and aerobic denitrification (SND) under high salinity was described by measuring the concentration of inorganic N. Halomonas sp. B01 synthesized ectoine under NaCl stress, and the intracellular ectoine concentration increased with increased NaCl concentration in the growth medium. When the NaCl concentration of the medium reached 120 g L−1, the malondialdehyde concentration and SOD activity were significantly increased to 576.1 μg mg−1 and 1.7 U mg−1, respectively. The growth-related and N removal–related enzymes of the strain were active or most active in medium with 30–60 g L−1 NaCl. The amoA of the strain cultured in medium with 60 g L−1 NaCl had the highest mRNA expression abundance. In the N removal medium containing 60 g L−1 NaCl and 2121 mg L−1 NH4+-N, SND by Halomonas sp. B01 was performed over 96 h and the N removal rate reached 98.8%. In addition to the protective mechanism of synthetic compatible solutes, Halomonas sp. B01 had the repair mechanism of SOD for lipid peroxidation. The growth-related and N removal–related enzymes of the strain were most active at a certain salt concentration; amoA also had the highest mRNA expression abundance under high salinity. Halomonas sp. B01 could efficiently perform N removal by SND under high salinity.  相似文献   
26.
目的和方法:本研究采用离子探针Fura2/AM 结合计算机图象分析技术,并通过施加NO合酶抑制剂LNNA和NO的作用靶———鸟苷酸环化酶(GC)的抑制剂美兰(Methylene Blue;MB),观察经培养的大鼠大脑皮层微血管内皮细胞和平滑肌细胞中的[Ca2+]i 在低氧作用后的变化以及与有关血管舒张因子NO和cGMP之间的关系。结果:低氧时大脑微血管内皮细胞和平滑肌细胞内的Ca2+ 浓度有所下降,变化幅度的大小与低氧的程度及低氧作用的时间有关,且可以被LNNA和MB所抑制。结论:低氧时大脑微血管的舒张反应与NO的产生有关,NO通过细胞内的多种机制,最终使得胞内Ca2+ 下降而导致血管舒张  相似文献   
27.
As a rich natural resource for drug discovery, Traditional Chinese Medicine (TCM) plays an important role in complementary and alternative medical systems. TCM shows a daunting complexity of compounds featuring multi-components and multi-targets to cure diseases, which thus always makes it extremely difficult to systematically explain the molecular mechanisms adequately using routine methods. In the present work, to reveal the systematic mechanism of herbal formulae, we developed a pathway-based strategy by combining the pathways integrating, target selection, reverse drug targeting and network analysis together, and then exemplified it by Reduning injection (RDN), a clinically widely used herbal medicine injection, in combating inflammation. The anti-inflammatory effects exerted by the major ingredients of RDN at signaling pathways level were systematically investigated. More importantly, our predicted results were also experimentally validated. Our strategy provides a deep understanding of the pharmacological functions of herbal formulae from molecular to systematic level, which may lead to more successful applications of systems pharmacology for drug discovery and development.  相似文献   
28.
以荒漠C3植物红砂(Reaumuria soongarica)和C4植物珍珠(Salsola passerina)为材料,在西北干旱荒漠区沿自然降水梯度,对不同降水条件下单生和混生红砂与珍珠根、茎、叶器官碳、氮、磷化学计量指标进行测定,分析其在不同生境下化学计量特征对种间关系及环境胁迫的响应规律。结果表明:(1)随干旱胁迫程度增加(降水量的减少),红砂各器官C含量平均升高7.73%,N、P含量分别平均降低6.20%、10.61%;珍珠各器官C含量平均升高7.36%,N、P含量分别平均降低5.93%、14.03%。两种植物叶片C含量升高表明其光合速率较低,生长缓慢,但对外界不利环境的防御能力增强,能更好地适应干旱环境。(2)干旱胁迫改变了红砂和珍珠的N、P含量在各器官的分配模式,两种植物N、P含量在叶部高于根部,在根、叶中N/P明显高于茎,表明两种植物不同器官受到的养分限制不同。(3)红砂各器官C、N、P含量高于珍珠,说明红砂防御能力较强,生长速率高,对资源的竞争和利用能力较珍珠强;珍珠C/N和C/P均高于红砂,表明珍珠比红砂有较强的碳同化能力和较高的营养利用效率。(4)在干旱胁迫条件下,红砂和珍珠均表现为碳素积累、氮磷素限制的格局,它们对于氮和磷的养分利用不活跃,受到氮和磷养分的限制较为均衡。  相似文献   
29.
随着畜牧业发展、宠物市场增长、气候变化、生态系统破坏以及旅行和商业全球化,人与动物之间的关系在全球范围内持续加强。人类与动物之间的联系不断升级,使得病原体的威胁也不断扩散。关于人兽共患疾病的研究多集中在由动物传染给人类的疾病,如疯牛病、艾滋病、禽流感等。但是微生物的交换是相互的,近年来越来越多的研究表明人类亦会将病原体传播给动物,包括新型冠状病毒、耐甲氧西林金黄色葡萄球菌、甲型流感病毒、隐孢子虫和蛔虫等。因此本文对人类疾病传染给动物的研究作一综述,为人与动物传染病的有效预防与控制提供参考。  相似文献   
30.
Wang Q  Yang Y  Chen X  Shao Z 《Biomacromolecules》2012,13(6):1875-1881
The conformation and eventual morphology of silk fibroin (SF) chains are crucial for the mechanical properties of SF materials, and are strongly related to the solvation step as a key stage in their processing conditions. In this work, a novel SF/AmimCl (1-allyl-3-methylimidazolium chloride) solution with unique properties is reported and compared with conventional regenerated SF aqueous solutions, based on an investigation of its rheological properties. The steady shearing behavior suggested that AmimCl is a good solvent for SF molecules, and shear thinning of semidiluted SF/AmimCl solution at high shear rates showed behavior similar to that in native spinning, which is due to the rearrangement and orientation of SF molecular chains. Fitting of experimental dynamic viscoelastic data to the Rouse model provided an effective method to estimate the molecular weight of SF. We believe that this work not only provides a better understanding of the relationship between properties of silk protein and aggregation states of their molecular chains, but also provides tools to fabricate high-performance SF-based materials.  相似文献   
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