自发突变

结果表明，MNNG的诱发突变率高于自发突变率27.8倍，并有剂量－效应关系。

Results showed that the mutation frequency induced by MNNG was 27.8 folds higher than that of the spontaneous mutation frequency and had dose-effect dependent .

HLFβ细胞自发突变率略有增加，但与对照细胞的差异无显著性，细胞周期分布及细胞恶性程度亦无明显改变。

No significant change was found between HLF β and the controls in spontaneous mutation frequencies , as well as cell cycle distribution and soft agar growths .

此外，细菌在有氧代谢过程中产生的ROS（reactiveoxygenspecies）是诱发自发突变的原因之一。

Moreover , reactive oxygen species ( ROS ), generated as by-products of aerobic metabolism , are thought to be the inducers of spontaneous mutations of bacteria .

背景与目的：研究小鼠淋巴瘤L5178Y3.2.7c-tk+/-细胞tk基因的自发突变频率和分子突变。

BACKGROUNDAIM : To investigate the mutation frequency and molecular mutation of spontaneous mutations on the tk gene of mouse lymphoma cells .

radiodurans这些基因在DNA错配修复途径中的作用。我们利用来自分析escherichiacoli碱基替换的突变分析系统&rpoB/Rif~R突变分析系统，测定和分析了自发突变导致D。

To further understand the functions of these genes , the rpoB / Rif ~ R mutation analysis system for analyzing base substitutions in Escherichia coli was used to D.

所有GDH~+变种，包括自亚硝酸诱发突变或自发突变来源的，都能诱导生成ADH。

All the GDH-positive mutants including those obtained by nitrous acid treatment and those of spontaneous origin are capable of inductive synthesis of ADH .

目的了解一株自发突变的宋内志贺菌S7株作为活疫苗受体的安全性。

Objective To study on the safety of a spontaneous mutant strain of Shigella sonnei S7 used as a living bacterial vaccine vector .

但是，仅pESnx／FL克隆可获得每皿50个以上的转化子和低于10－4的自发突变率，符合穿梭质粒测试系统的要求。

The spontaneous mutation frequency was less than 10-4 in pESnx / FL. Therefore , pESnx / FL accord with the requirements of shuttle vector plasmid mutation test system .

因此，除自发突变方法外，60Co-γ射线辐照诱变也被证明是一种获得发酵性能优良的Lactobacillusdelbrueckii抗噬菌体菌株的简便有效方法。

Therefore , besides spontaneous mutation , the 60Co - γ ray irradiation was also proved to be a simple and effective method for obtaining phage-resistant mutants from Lactobacillus delbrueckii strains with high technological performance .

自发突变或遗传操作（敲除或下调）造成的MSTN失活，已经被报道可以增加许多种动物的骨骼肌数量。

Dysfunction of MSTN gene either by natural mutation or induced through genetic manipulation ( knock out or knock down ) has been reported to increase the muscle mass in mammalian species .

我们从籼稻品种9311中发现一自发突变的矮秆水稻，该突变体与矮秆突变体dwarf-1相似：茎短而壮；

A spontaneous dwarf mutant used in this study was identified from a indica cultivar 9311 . The dwarf phenotype was similar with that of dwarf-1 mutant with short and stout stem , dark green , short , thick but broad leaves , little grain shape .

动物病毒的突变有自发突变和诱发突变。

Spontaneous and induced mutation occur with animals viruses .

诱发突变率为自发突变率的7.0～9.3倍，接近一个数量级。

Mutagenesis rate are higher than that of spontaneous mutation by 7.0 ~ 9.3 times .

应用自发突变的原理成功地从溶菌液中筛选到抗噬菌体的工程菌株；

An anti-bacteriophage engineering Escherichia coli was directly selected from the ferment lysate by spontaneous mutation .

但科学家们发现了一种自发突变，可使番荔枝的近亲，一种叫释迦的水果，变成无核水果。

But the scientists found a spontaneous that causes seedlessness in a cherimoya relative , the sugar apple .

正是因为生殖细胞&精子和卵细胞中的自发突变，我们每一代人之间才会产生微妙的差异。

Because of spontaneous mutations in germ cells sperm and eggs each generation of our species is subtly different .

溶源性测定结果表明，除2株自发突变获得的抗性菌株外，其他58株突变菌株的噬菌体抗性均与溶源性无关。

Except for 2 spontaneous mutants , the phage-resistant mechanisms of the last 58 mutants were irrelevant with lysogeny .

通过多次转化筛选，获得了一种高量表达绿色荧光蛋白基因gfpmut2的自发突变质粒。

By repeating transformation and selection , a spontaneous mutant of plasmid over expressing green fluorescent protein was obtained .

他们同时也检查这些基因瑕疵是否是自发突变，而不是从父母传递给子女的。

They also checked whether those gene glitches were spontaneous mutations , which weren 't passed down from parent to child .

传统理论认为肿瘤细胞有很高的自发突变几率，随着时间的推移，自然就产生抗药的细胞。

Traditionally , tumor cells are considered to have a high spontaneous mutation rate , so drug-resistance tumor cells will emerge naturally .

存在修复机制，由此导致了生物体的特殊基因座不同的自发突变频率。

Lastly there was a sort of repair-mechanism , and hence it leaded to the different frequency of spontaneous mutation of bion 's special-genes place .

自发突变的可能性，这在经济领域中通常称为创新，主要是（不过不一定总是）技术方面的。

The potential for spontaneous mutation , usually referred to in the economic world as innovation and primarily , though by no means always , technological .

此外，还就诱发突变和自发突变矮源的共性以及寻找或创造新的非等位矮源的意义进行了讨论。

The common property between induced dwarf mutant and spontaneous dwarf mutant and the significance of seeking or creating newly non-allelic dwarfs have also been discussed .

香蕉是世界重要的热带水果，因其多为三倍体，长期以来，香蕉育种多以筛选突变体为主，然而，人们对香蕉自发突变的分子机理知之甚少。

Banana ( Musa spp. ) is very important fruits around the world . For a long time , the principal means for banana breeding were selected mutants because of its triploid . However , the molecular mechanism of banana mutations poorly understood .

啤酒酵母的改良途径有：诱变选育，选择自发突变株，无外源遗传损伤，较稳定，但突变频率低，需富集；

The improvement measures for beer yeast were as follows : culture selection by induction mutation , it refered the selection of spontaneous mutation strains which were comparatively stable in quality and suffered no exterior inheritance damage , but the low mutation frequency required the accumulation of microbes ;

更重要的是小鼠遗传资源丰富，已经成功培育478个近交系，通过自发突变、诱发突变和转基因技术等途径培育并保存了2000多个突变品系。

The most important characteristics of mouse are their abundant genetic resources . Up to now , 478 inbred strains have been cultured , and more than 2 000 mutant strains have been established by either spontaneous , inducible methods or transgenic technology , and conserved in world .

丙烯酰胺诱发突变主要由点突变和缺失两部分组成（40.0%～66.7%，33.3%～60.0%），而自发突变几乎全是点突变（90.0%以上），两种细胞均无全基因缺失型；

The most frequent spontaneous mutation was point mutation (≥ 90.0 % ) and acrylamide induced mutation mainly included partial deletion and point mutation ( respectively 40.0 % - 66.7 % , 33.3 % - 60.0 % ) . Total gene deletion was not discovered in both of cells .

但每秒也有数百万个这样的错误纯粹是偶然发生&这种随机自发的突变可能是最普遍的一种致癌因素。

But millions every second occur purely by chance & random , spontaneous glitches that may be the most pervasive carcinogen of all .

要充分利用突变小鼠作为研究模式，则需要诱发突变或自发基因突变之正确基因表现型特徵。

Making full use of mutant mice as research models requires correct characterization of the phenotypes that result from induced or spontaneous genetic mutations .

此类突变小鼠通常由自发或诱发突变得来。

This mutant mouse can be obtained by spontaneity or artificial method .