52 resultados para Lannoy, Ghillebert de, 1386-1462.


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栉孔扇贝是我国重要的海水养殖品种,自1997年以来陆续爆发的大规模死亡,不仅造成了巨大的经济损失,而且直接威胁到现有产业的生存和发展。本研究通过比较扇贝在连续刺激条件下的不同免疫反应,推测栉孔扇贝中有无免疫致敏和记忆现象,观察短期免疫刺激对扇贝再次遇到相同病原物刺激时死亡率的影响,探讨栉孔扇贝的免疫致敏作用,并对其机制进行初步探讨,以期更好地了解扇贝的免疫防御机制,为扇贝病害防治提供参考。 利用荧光实时定量PCR技术检测了扇贝受到鳗弧菌连续等量刺激后两种重要病原识别受体(PRR)基因的表达。结果显示,在受到连续两次刺激后CfPGRP-S1、LGBP基因的表达量均有不同程度的增加。其中CfPGRP-S1基因在受到第二次刺激后表达量增加的幅度高于第一次,且基因表达显著性增加的时间比第一次提前;LGBP基因在第二次刺激后,表达量显著性增加的时间也比第一次提前。同时,对同批处理的扇贝进行重要免疫指标的检测分析发现两次刺激后吞噬率变化不显著,而第二次刺激后吞噬指数的最大峰值高于第一次,并且最大峰值出现的时间比第一次提前;血淋巴中的抗菌活力和肝胰腺中SOD、MDA含量在两次刺激前后的变化不显著。在脊椎动物中,识别能力和抗菌能力的提高是免疫记忆的两个重要特点,栉孔扇贝在第二次免疫刺激后PRR识别能力的提高和吞噬作用的增强,说明扇贝中可能存在类似脊椎动物免疫记忆的免疫致敏作用。对扇贝进行两次鳗弧菌浸泡刺激,第一次为短期浸泡刺激,第二次为长期浸泡刺激。结果发现,第一次浸泡过的扇贝在遭受相同病原第二次刺激时,在一定时间段内其死亡率比未受第一次刺激的扇贝极显著降低,表明第一次的短期病原刺激增强了扇贝对第二次刺激的抵抗能力。同时比较第二次刺激过程中扇贝免疫指标的变化发现经过短期刺激扇贝的吞噬作用、ACP和AKP活性比未受过刺激的扇贝显著增强,而其他指标包括POL、SOD则差异不显著,说明增强的吞噬作用、ACP和AKP活性与扇贝的死亡率下降有关。研究结果表明栉孔扇贝中存在免疫致敏(immune priming)现象,短期刺激可以提高扇贝的免疫反应能力,增强扇贝机体对相同病原物的抵抗能力。

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本论文对两种红树林植物海漆 (Excoecaria agallocha L.) 和海桑(Sonneratia caseolaris L.)的化学成分进行了系统研究。 采用常规的硅胶柱层析、制备薄层层析、凝胶 Sephadex LH-20 柱层析、MCI柱层析、反相硅胶柱层析、半制备型 HPLC 以及重结晶等手段,从海漆 (Excoecaria agalloch L. ) 中分离得到 40 个化合物,从海桑(Sonneratia caseolaris L.)中分离得到 30 个化合物。利用各种现代波谱技术 (IR、UV、ESI-MS、EI-MS、1D-NMR、2D-NMR等) 及其化学物理性质,确定了海漆中 32 个化合物的结构,其中包括 1 个新的三萜天然产物以及 15 个首次从海漆中报道的化合物;确定了海桑中 27 个化合物的结构,其中包括 1 个新化合物和一个首次报道其碳谱数据的化合物。本文为首次报道海桑的化学成分研究。 对海漆和海桑粗提物及分离得到的部分化合物进行了抗肝癌细胞毒活性筛选,化合物S22表现出较强活性,其IC50为2.8 μg/mL;海漆和海桑粗提物及其它部分单体化合物只表现出微弱活性;阳性对照丝裂霉素C的IC50为1.1 μg/mL。 对分离得到的部分样品还进行了抗菌活性测试,各样品在测试浓度下对测试菌均未表现出明显的抗菌活性。 首次研究了海漆挥发性成分及其季节性变化。利用水蒸汽法提取了不同季节海漆的挥发性成分,通过GC-MS鉴定其化学组成,发现脂肪酸、二萜和倍半萜是海漆挥发性成分的主要组成,不同季节的挥发性成分差异较大。

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A rapid capillary electrophoresis method for the separation of five natural pharmacologically active compounds from extracted Rhodiola, namely salidroside, tyrosol, rhodionin, gallic acid and ethyl gallate has been developed. The separation of five natural pharmacologically active compounds was carried out in a fused-silica capillary with 14 mM boric acid, 30 mM SDS and 2.5% acetonitrile, adjusted to pH 10.7 with NaOH. Applied potential was 21 kV. The temperature of the capillary was maintained at 25 degreesC by the instrument thermostating system, with the correlation coefficients of 0.9805-0.9989 for migration time, and relative standards of < 3.52% for peak areas. The established method is rapid and reproducible for the separation of five natural pharmacologically compounds from extracts of Rhodiola with satisfactory results.

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本发明涉及一种利用大黄属植物地上部分提取蒽醌类物质的工艺,该工艺设备简便、溶剂低廉、可回收重复利用,工艺提取效率高,所得提取液安全、纯度高。

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Migration carriers act as the “Bridges” connecting source rock and traps and play important roles in petroleum migration and accumulation system. Among various types of carriers, sandstone carrier constitutes the basis of carrier system consisting of connected sandstone bodies, of sand-bodies connected with other carriers, such as faults and/or unconformities. How do we understand sandstone carrier beyond the traditional reservoirs concept? How could we characterize quantitatively this kind of carriers for petroleum migration? Such subjects are important and difficult contents in dynamic studies on hydrocarbon migration and accumulation. Sandstone carrier of Chang 8 member in Longdong area of Ordos Basin is selected as the research target in this thesis. Through conducting integrated reservoir analysis on many single wells, the correlation between single sandstone thickness and oil thickness seems good. Sketch sandstone is defined in this thesis as the principal part of carrier based on systematical analysis on lithology and sandstone thickness. Geometry connectivity of sandstone bodies was identified by the spatial superposition among them and was proved by the oil property features in oilfields. The connectivity between sandstone carriers is also hydrodynamically studied by observing and analyzed various diagenetic phenomena, especially the authigenic minerals and their forming sequence. The results were used to characterize transporting capability of sandstone carriers during the key petroleum migration periods. It was found that compaction and cementation are main causes to reduce pore space, and resolution may but not so importantly increases pore space after the occurrence of first migration. The cements of ferrocalcite and kiesel seem like the efficient index to demonstrate the hydraulic connection among sandy bodies. Diagenetic sequence and its relationship with petroleum migration phases are analyzed. Sandstone carrier of Chang 8 member was then characterized by studying their pore space and permeable properties. The results show an average porosity and permeability of Chang 8 carriers are respectively 8% and 0.50md, belongs to low porosity - low permeability reservoirs. Further, the physical properties of Chang 81 member are commonly better than those of Chang 82 member. Methods to reconstruct property of sandstone carrier during petroleum migration phase (late Jurassic) are built based on diagenetic sequence. Planal porosity, porosity and permeability of sandstone carrier in this period are statistically analyzed. One combining index - product of thickness and ancient porosity - is selected as the idea parameter to characterize sandstone carrier of late Jurassic after contrast with other parameters. Reservoirs of Chang 8 member in Longdong area are lithological reservoir controlled by sand body in which oil layers in middle part are clamped with dry layers in upper and lower parts, in a sandwich way. Based a newly proposed “migration-diagensis-remigration” model in low permeability sandstone of Chang 8 member in Longdong area, oil migration and accumulation processes during different periods are simulated with the reconstructed sandstone carriers system. Results match well with current reservoir distributions. Finally, suggestions for next favorable exploration areas are given based on all research achievements.

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By first principle methods based on density functional theory (DFT),the equation of state(EOS) and elastic constants of both periclase and ferropericlase are calculated. The pressure and iron doping effects on the elastic constants of ferropericlase are investigated systematically. Firstly, we calculate the elastic constants of periclase and compare the obtained results with experimental data and other theoretical calculations, which shows a encouraging consistence and demonstrates the practicability of first-principle methods. Secondly, by adding iron into periclase crystal model, we build up ferropericlase with iron contents ranging from 0% to 25% mole percent. The corresponding elastic constants are calculated in a large pressure range(0~120GPa). Emphatically, the strong correlation of 3d electrons in transitional elements, such as iron, is difficult to treat in first-principle methods for a long time. The current solution is to make additional correction. During the initial stage of this study, the strong correlation of 3d electrons in iron is not considered, and we observed that addition of iron decreases the volume of ferropericlase, which is totally contradictory to the experimental data. By applying LDA+U approximation in order to solve the strongly correlated 3d electron of iron, we observed the expansion of volume by iron as expected. On the basis of the LDA+U approximation, the elastic constants of ferropericlase are calculated. After a detailed analysis of data obtained from theoretical calculations, we have reached the following conclusions:(1)pressure imposes positive effects on all elastic constants, and the degree of effects is C11>C12>C44. (2) Iron has no distinctive effects on C11 and C12, although some fluctuations are observed around 60GPa. However, iron has obvious softening effects on C44 The softening effects on C44 are intensified as pressure increases. Above the 100GPa, the effects increase greatly, even surpasses the pressure's positive effects in ferropericlase crystal models with iron mole percent of having 12.5%, 18.75% and 25% iron content. (3)As to the modulus deprived from elastic constants, iron has no effect on the adiabatic bulk module BS, only a little fluctuation around 60GPa. We find iron's softening effects on shear modulus G. (4)We find out that, compared with low iron content, elastic constants with iron content approaching 25mole% is consistently fluctuated,which may be caused by the limitations of the LDA+U approximation method itself. (5)We investigate the pressure and Fe doping effects on elastic anisotropy factor(A=(2C44+C12-C11)/C11) of ferropericlase and find out that iron contents will lower the critical isotropic pressure. At the same pressure, when the pressure is below the isotropic pressure, iron softens the anisotropy factor ; when pressure surpasses the isotropic pressure, iron increases the anisotropy factor.