终止链

Termination of free radical chairs occurs by a bimolecular reaction.

自由基链的终止产生于双分子反应。

Five plasmids for the expression of doxA gene, which were designated as pYG57, pYG502, pYG503, pYG505 and pYG506 were constructed so that the cloned doxA gene were under the control of either promoter of melanin gene or erythromycin resistant gene or their tandem promoters, and a fd terminator downstream.

构建了五个doxA基因链霉菌表达质粒pYG57、pYG502、pYG503、pYG505和pYG506，使得doxA基因在上游的Pmel启动子、红霉素抗性基因启动子或者两者的串联启动子，以及下游的fd终止子控制之下。

By using PCR method, a 1kb fragment was gained from Heliothis amigera nuclear polyhedrosis virus genome. The whole fragment was sequenced by dideoxided chain termination methods and a full open reading frame which encode 299 amino-acids was found. The molecular weight of the peptide is about 35 kilodalton.

用PCR方法从棉铃虫核多角体病毒基因组中扩增到了1kb的DNA片段，用双脱氧链终止银染测序法测定了该片段的全序列，发现它含有一个完整的开放阅读框，编码299个氨基酸残基的多肽，分子量约35KD。

To localize the functional positions of biomolecules in ciliates cell, we constructed a macronuclear artificial chromosome containing a gene encoding red fluorescence protein based on the structural characteristics of ciliates chromosome.

为了能够有效地分析生物大分子在该细胞中的功能作用位点，本研究根据该生物染色体结构的特征，构建了含有红色荧光蛋白的大核人工染色体EoMAC_R，并与之前构建的含绿色荧光的大核染色体EoMAC_G一起，对蛋白质合成终止有关的3个重要因子核糖体大亚基蛋白L11、多肽链释放因子eRF1和eRF3在八肋游仆虫细胞中进行了荧光共定位分析。

Glioma is still one of refractory disease in the neurosurgical field; the development of new primary and adjuvant treatment is vital. Recently, the gene therapy of glioma is developed rapidly and there are many methods about the gene therapy that include: suicide gene therapy, immunologic gene therapy, drug resistangce gene therapy, angiostatin gene therapy and so on. The sucide gene therapy is the most potential approach of antitumer, these nonmammalian genes encode enzyme that convert nontoxic prodrugs into highly toxic metablites. Cells transfected with suicide genes are targeted for specific negative selection, witch can be induced by administrtion of the corresponding produg. Among the enzyme/produg combinations, two of the best characterized system are herpes simplex virus thymidine kinase /ganciclovir and Escherichia coli cytosine deaminase /5-flourocytosine (5-FC). The formor can convert the antiviral nucleoside analogs acyclovir , ganciclovir to their nucleoside monophosphate derivatives, the monophosphate forms are subsequently phosphorylated by endogenus cellular kinases to triphosphates, these molecules are potent inhibitors of DNA synthesis.

近年来脑胶质瘤的基因治疗发展迅速，应运而生的方法有自杀基因、免疫基因、多药耐药基因以及抗血管生成基因等，其中自杀基因被认为是最有前景的基因治疗方法，它又称病毒介导的酶／药物前体疗法，是利用转基因技术将哺乳动物细胞中所不含有的自杀基因转入到哺乳动物肿瘤细胞中，该基因表达的产物可将无毒的药物前体转化为毒性药物，从而选择性杀伤该肿瘤细胞，常用的自杀基因有单纯疱疹病毒-胸苷激酶基因和大肠杆菌胞嘧啶脱氨酶基因，前者催化无毒性抗病毒核苷类似物如丙氧鸟苷、无环鸟苷等成为单磷酸核苷衍生物，然后在内源性细胞激酶作用下转化为具有明显毒性的三磷酸核苷，作为DNA合成链的终止剂和DNA合成酶的抑制剂，干扰细胞DNA的合成；后者编码的胞嘧啶脱氨酶可催化5-氟胞嘧啶（5-FC）脱氨成为5-氟尿嘧啶（5-FU），然后代谢为有毒性的5-氟尿嘧啶-5′三磷酸（5-FUTP）和5-氟-2′脱氧尿嘧啶-5′磷酸（5-FdUTP），5-FUTP通过与UTP竞争性结合而抑制mRNA和tRNA的合成，5-FdUTP则作用于胸苷合成酶，导致TMP衰竭而阻止DNA的合成，最终诱导肿瘤细胞凋亡。

In this study, the DNA fragments coding for amino acids 133～158 of VP1and 20～34 of VP4protein of type Asial FMDV were chemically synthesized and ligated into a tandem repeat 133～158-20～34-133～158. The sequences of signal peptide of Igκ chain and Kozak were fused to the 5'end of this tandem sequence and synthetic oligodeoxynucleotide containing CpG-ISS was fused to downstream of terminal coden of this tandem sequence. And then this long fragment was cloned into the eukaryotic expression plasmid pHook-2, forming a new secreted expression plasmid, named pAS1-E.

在第二章证明了亚洲Ⅰ型口蹄疫病毒VP1蛋白中133～158位氨基酸残基确是一重要B细胞中和抗原表位的基础上，依据第一章获得的口蹄疫病毒亚洲Ⅰ型VP1 cDNA序列及已报道Asial VP4序列，采用真核偏爱密码子化学合成了VP1中编码133～158位氨基酸及VP4中编码20～34位氨基酸这两个抗原表位基因，将其组成133～158-20～34-133～158串联结构，在其5′端加上鼠Igκ链信号肽序列，在翻译调节区加上增强表达的Kozak序列，同时在133～158-20～34-133～158串联结构3'端终止密码子下游加上CpG免疫刺激序列，将这些片段连接后，克隆到真核表达载体pHook-2上，构建成功了DNA疫苗重组表达载体pAS1-E。

Normal mammalian guanylate kinase metabolizes the monophosphate to the diphosphate form and then to the triphosphate form .

GCV-TP对细胞具有剧毒性，可抑制DNA聚合酶的活性，并可掺入到DNA链的末端作为终止剂。

The effect of residence time on the mechanism of chain termination of An freeradical polymerization was discussed.

探讨停留时间对丙烯腈聚合反应自由基链终止方式的影响。

The water aerosol fire-extinguishing agent is a new generation of Halon replacement.

水基热气溶胶灭火剂是以替代卤烃灭火介质为目的而研制的新一代灭火剂；主要通过燃烧产物中惰性气体对火焰的窒息、水蒸汽对火焰的冷却以及微细金属盐颗粒对燃烧链反应的终止来实现高效灭火的目的。

Sanger, F., et al. 1980. Cloning in single-stranded bacteriophage as an aid to rapid DNA sequencing. J. Mol. Biol.

Sanger酶学法的原理[2]即用双脱氧核苷酸作为链终止试剂，通过聚合酶的引物延伸产生一系列大小不同的分子后再进行分离的方法。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。