查询词典 mutation

Mutation of the gARID1 binding site in the cwp1 promoter resulted in a decrease of promoter activity and mRNA levels during vegetative growth and encystation, suggesting that the gARID1 binding sites are positive cis-acting elements of the cwp1 gene promoters in both trophozoites and encysting cells. Using cotransfection assay, we also found overexpession of gARID1 can increase luciferase activity and mRNA levels, while mutation of the gARID1 binding sites of the cwp1 promoter resulted loss of this transactivation.

我们也用萤光酵素基因接上cwp1基因启动子，如果将其cwp1启动子上的gARID1结合位置突变，也可以发现萤光酵素和讯息RNA的表现有明显的下；再用cotransfection assay，可发现gARID1会使萤光酵素和讯息RNA表现明显上升，然而如果将其cwp1启动子上的gARID1结合位置突变，这种转活化则消失。

The heat source in mid-Africa presents weaken mutation in 70 's, but that in the Philippines in the tropical western Pacific and the southwest of Caribbean present enhancive mutation.

5冬季南美洲北部热源具有明显的年代际变化，70年代中期存在增强突变，南非和海洋大陆至印度洋一带热源存在增强变化趋势，而澳大利亚西北至南太平洋一带热源存在减弱变化趋势。

In this paper, the advances in research of laser mutation breeding mechanism was expounded and the application and achievements in breeding of agriculture, pasturage, farrier and industry microorganism of laser mutation were introduced.

阐述了激光诱变育种机理的研究进展，介绍了激光诱变在农作物、畜牧兽医、工业微生物育种上的应用及取得的成果，并介绍了激光诱变育种的一般操作过程，最后展望了激光诱变育种今后的研究前景。

At the early iteratives, the mutation rate is bigger and the aim is to make particles to explore smaller and isolate region and to avoid the algorithm trapping to the local optimum. While the algorithm runs, the mutation rate will be decreased to reduce the disturbing to the particles. IPSO adopts a new method that congregates some neighboring individuals to form multiple sub-populations in order to lead particles to explore new search space. Additionally, our algorithm incorporates a mechanism with a simple and easy penalty function based on the largest distance between the particle and the boundary of the feasible region to handle constraint.

IPSO采用了一种新型的变异策略，变异概率随着算法的运行是动态变化的：在算法运行初期，变异概率大，其目的是使算法不但能够探测到目标空间中的孤立区域，而且避免搜索陷入局部极值；在算法运行后期，变异概率逐渐变小，以减少对粒子的扰动；算法通过将部分具有邻近距离的粒子聚集成核形成多子群引导种群中粒子的飞行；采用一个简单的基于粒子与可行域边界最远距离的罚函数处理约束的机制，使得算法高效实现。

For the disease to occur, a sperm carrying the mutation (50:50 chance) must fertilise an egg carrying the mutation (50:50 chance).

为疾病的发生，精子进行基因突变（ 50：50机会）必须受精鸡蛋进行突变（ 50：50机会）。

A new RHAG mutation was found firstly in Chinese population,it is a 582 C＞T homozygosity mutation in RHAG gene.

首次在中国人群RhD变异型标本中发现一例新的RHAG等位基因，该等位基因是RHAG外显子第582位C＞T杂合突变。

Results: Tyr486Asp missense mutation in Exon 5 of UGT1A1 gene was found and homozygote of the mutation was confirmed in the proband.

结果：该先证者UGT1A1基因的第5外显子第486密码子发生了T→G碱基的错义突变，导致了酪氨酸变成了天门冬氨酸(Tyr486Asp)。

Objective To investigate the gene mutation in two pedigrees with X-linked ichthyosis and explore the relationship between the mutation and clinical manifestations.

目的 研究X性连锁遗传鱼鳞病家系基因突变，探讨基因突变与临床表现的关系，为进一步开展基因诊断和基因治疗奠定基础。

The key points of DGA is to start evolution with initial population evenly distributed in searching space to avoid the leakiness of subspace, to accelerate the searching process by directed crossover and mutation, to improve holistic survival and adaptive ability by means of competition and parallel evolution in genetic system. However, the crossover and mutation act on different lays in space made the searching uniform.

其基本思路是以空间上均匀分布的初始点展开演化以避免子空间的遗漏，以有方向性的杂交和变异加速和调节搜索，同时杂交和变异作用在不同层面上使搜索在整体上均匀化，通过遗传系统里的并行竞争提高整个群体的生存适应力，从而达到整体优化的目的。

In this paper, we propose an improved evolutionary programming using a mixed strategy based on Gaussion mutation and single-point mutation, which is named SPCEP.

本文提出一种基于经典进化算法和单点变异算法的混合策略进化算法SPCEP。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。