酰化作用

It also classifies them in accordance with the compound method of triazene reagents as follows: reagents diazotizated with sodium nitrite and muriatic acid, reagents diazotizated with nitrosyl positive ion, reagents diazotizated with n-butyrate nitrite.These reagents with high sensitivity and good choice have been widely applied to the determination of microa mounts of cadmium and...

按三氮烯类试剂合成的方法进行分类，分别为在亚硝酸钠和盐酸作用下重氮化的试剂，在亚硝酰正离子作用下重氮化的试剂，在亚硝酸正丁脂作用下重氮化的试剂，此类试剂灵敏度高，选择性好，广泛应用于被镉、汞等过渡金属离子污染的环境样品的分析中。

BMI-1(B-cell-specific Moloney murine leukemia virus integration site 1), a Polycomb group repressor, is always present as a PcG complex combined with RING1, HPC2, Mph2, et al. BMI-1 prolongs cells'capacity to proliferate and represses their senescence by repressing the transcription of CDKN2A through acetylhydrolasing or deacetylhydrolasing the Polycomb response elements in chromosome.

BMI-1 (B-cell-specific Moloney murine leukemia virus integration site 1)属于PcG家族，它与该家族其他成员如RING1，HPC2，Mph2等结合形成蛋白复合体，作用于染色质PREs位点，通过对组蛋白进行乙酰化和去乙酰化修饰，从而稳定抑制CDKN2A转录，最终促进细胞的增殖并抑制细胞凋亡。

The glutamine synthetase produced by the engineering bacteria can specially act on NH4 and aminoglutaric acid, the durability to the high concentration ammonium ion has been distinctively improved because of the dissolution of adenosine acylation modification, the major bottleneck of glutamine with enzymatical production has been solved, and the concentration of the obtained glutamine can reach 47.6g/L.

本发明工程菌产的谷氨酰胺合成酶可专一性的作用于NH 4 和谷氨酸，且因解除了腺苷酰化修饰作用对高浓度铵离子的耐受能力显著提高，解决了酶法生产谷氨酰胺的重要瓶颈，生成的谷氨酰胺的浓度最高达到47.6g/L。

Firstly, 3-ethylthiobutanal was prepared from crotonaldehyde reacting with ethanehiol in triethylamine with high yield. Secondly, methyl acetoacetate was converted to 6-ethylthiohept-3-en-2-one by three steps via hydrolysis, condensation with 3-ethyltio-butanal and dehydration, then 6-ethylthiohept-3-en-2-one was cycloco ndensed with dimethyl malonate by Michael addition and Claisen condensation, followed by saponification and decarboxylation to give the intermediate of 5-(2-ethylthiopropyl)-cyclohexane-1,3-dione.

首先，以巴豆醛与乙硫醇为原料，在三乙胺的催化作用下高收率制得3-乙硫基丁醛；然后从乙酰乙酸甲酯出发，通过碱水解、与3-乙硫基丁醛缩合、脱水三步反应合成6-乙硫基-3-烯-2-庚酮，接着6-乙硫基-3-烯-2-庚酮与丙二酸二甲酯通过Michael加成和Claisen缩合成环，再通过皂化和脱羧反应生成中间体5-[2-丙基]-1，3-环己二酮；再与丙酸酐反应丙酰化，最后与0-3-氯-2-丙烯基羟胺肟化，得到目标化合物烯草酮。

In this review, we discussed the consequences of inhibiting histone deacetylases in cycling versus non-cycling cells, in light of the dynamics of histone acetylation patterns with a specific emphasis on heterochromatic regions of the genome.

本综述通过讨论HDACIs对周期和非周期细胞中组蛋白去乙酰化酶的抑制结果，来阐明组蛋白乙酰化模式的动力学特征，特别是对基因组异染色质的作用。

NOBS PAG , can obviously activate hydrogen peroxide thus , the efficiency of hydrogen peroxide bleaching can be advanced greatly .

研究结果初步表明，此类有机酰化剂类如：四乙酰乙二胺，四乙酰甘脲，异壬酰氧基苯磺酸钠，五乙酰葡萄糖等有着非常明显的活化过氧化氢的作用，从而能在很大程度上提高纸浆过氧化氢漂白的效率。

Virtually every enzyme in glycolysis, gluconeogenesis, the tricarboxylic acid cycle, the urea cycle, fatty acid metabolism, and glycogen metabolism was found to be acetylated in human liver tissue.

这一命题中的关键之处在于乙酰化在生物调控中的重要作用。目前蛋白质组学已经发现了上千的被乙酰化的哺乳动物蛋白，中国科学家的这些发现证明了代谢酶。

Methods After treated with a specific demethylating agent,Aza and acetylating agent, TSA, the status of 5'CpC island methylation of ING1b gene in HT29 human colon cancer cell line was analyzed using methylation specific polymerase chain reaction,and the level of histone acetylation was analyzed by chromatin immunoprecipitation,and reverse transcription polymerase chain reactionwas used to examine ING1b mRNA expression.

应用特异性DNA甲基转移酶抑制剂5-氮-2'-脱氧胞苷（5-Aza-2'-dc，以下简称Aza）及组蛋白去乙酰化酶抑制剂曲古抑菌素A作用人结肠癌细胞株HT29后，用甲基化特异性PCR检测该ING1b基因核心启动子区域CpG岛甲基化情况，用染色质免疫沉淀检测其乙酰化组蛋白绑定的DNA情况，并用逆转录聚合酶链反应检测ING1bmRNA表达。

Results showed that there were the morphological changes of mitochondria, such as vacuolization, degeneration and cristae swelling or disappearance, in HT-29 cells treated by C2-ceramide for 24 hours. Under the fluorescence microscope, mitochondria of apoptotic cells aggregated and emitted red fluorescence, however, mitochondria of normal cells emitted green fluorescence. The mitochondrial membrane potential began to decrease after 6 hours in HT-29 cells treated with C2-ceramide in time and dose dependent manner.

结果显示C2-神经酰胺作用HT-29细胞24小时，线粒体发生空泡化、变性、嵴肿胀或消失等形态学改变；此时荧光显微镜下可观察到线粒体聚集，发出红色荧光，而正常细胞线粒体发出绿色荧光。C2-神经酰胺作用细胞6小时，线粒体膜电位即开始降低，呈时间-剂量-效应关系。

The kinetic approach of the substrate reaction during modification of enzyme activity has been applied to a study on the kinetics of the course of inactivation of metal enzyme by metal ion chelator and reactivation of apo-enzyme by metal ion restoration.

应用邹承鲁先生建立的底物反应动力学的理论研究了含金属锌离子的氨基酰化酶在金属螯合剂的作用下去金属失活的动力学研究和去金属失活的氨基酰化酶与金属离子重组恢复活性的动力学过程的研究中。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。