突变形成

Mutants related to shoot branching are isolated in pea? Arabidopsis? petunia? rice? tomato and maize, such as revoluta? pinhead? monoculm1(moc1)? lateral suppressor? blind/torosa related to axillary meristem initiation; more axillary growth? ramosus? decreased apical dominance associated with axillary meristem outgrowth; supershoot/bushy? Teosinte branched1 (Tb1) contacted with axillary meristem initiation and outgrowth.

在豌豆、拟南芥、矮牵牛、水稻、番茄和玉米中获得到很多与分枝发育相关的突变体，如与腋生分生组织的形成有关的revoluta、pinhead、monoculm1(moc1)、lateral suppressor、blind/torosa等突变体；与腋生分生组织的生长有关的more axillary growth、ramosus、decreased apical dominance等突变体；与腋生分生组织的形成和生长都有关的、supershoot/bushy、teosinte branched1(tb1)等突变体。

The results showed that the changes of the types were not caused by new cell mutation, but by translocation of the different cell types of variegation. The changes of division direction of white cells and green cells resulted that some of the green epidermal cells translocated into the second layer and it pushed furthermore the origin white cells of the second layer into the third layer, so that the variegation altered.

Pollock'突变型异化不是由于细胞突变形成，而是由于质体突变型白色细胞和原型绿色细胞在生长发育过程中相互竞争转轨所致，即白色细胞和原型绿色细胞改变了分裂方向，部分表皮绿色细胞进人第二层，挤压第二层白色细胞转轨进人第三层，导致细胞类型的移位，从而形成异型斑。

A sudden or marked change.突变 Of or regulated by one gene or one of a pair of allelic genes.

一个基因分子内部进行带基本性质的重新组合所形成的突变。

In the current study, we have detected the mtDNA mutation in lung cancer, investigated the correlation between the mtDNA mutations and carcinogenesis, and explored the possibility of mtDNA mutations as a biomarker. We also analyzed the reasons for the homoplasmic mutations of mtDNA.

为了探讨mtDNA突变在肺癌发生中的意义、mtDNA突变在肺癌早期诊断中作为分子标记的可能性以及mtDNA多态性与肺癌易感性的关系，我们检测了肺癌mtDNA突变，分析了肿瘤中mtDNA同质性突变的形成原因。

After the selection from one to three generations, several mutants were obtained. The major mutants included non-nodule mutants (18 lines) which failed to nodulate after inoculated with rhizobia for two weeks, ineffective nodulation mutants (9 lines) which had less uneven and white or transparent nodules, an abnormal leaf and flower mutant which was dwarf without stipules, abnormal flowers and less nodules, and a slender mutant with a thin stem and smaller leaves.

从种植的三代植株中，筛选到多种共生固氮根瘤的突变体，其中不结根瘤突变体18个株系，表现为接种根瘤菌两周后无根瘤形成；结无效根瘤突变体9个株系，表现为根瘤数目少且分布不均匀，根瘤呈白色，有些为半透明；花叶形态异常突变体1个株系，表现为除根瘤数目少外，植株矮小、托叶消失、花形态异常；纤细突变体1个株系，表现为除根瘤数目少外，植株变小、茎细叶小。

Systematic infection of mice is used as a model to test the virulence of several mutants. According with their ability to form hyphae, nonfilamentous mutant is avirulent, and hyphae defective mutants have decreased virulence.

用系统感染小鼠模型分析这些突变株的致病能力，同它们形成菌丝的能力相一致，野生菌的致病能力最强，形成菌丝弱的突变株致病能力也减弱，不能形成菌丝的cph1 efg1突变株和crk1则无毒性。

All the LOH on 〓 and 〓 was observed in invasive ductal carcino- ma, carcinoma simplex, medulary carcinoma and scirrhous carcino- ma, no deletions at these sites were observed in any invasive lobular carcinoma and others. These results imply an etiological difference.P53 gene is a hot point gene in the occurrence and development of breast, cancer. PCR-SSCP analysis was performed to detect P53 gene point mutation in the region between exon 5 and 8, 5 of 12 (41. 6%) stage I breast cancer patients contain mutation of P53, 3 of 5 patients were accompanied by 〓 deletion. These results suggested that point mutation and allelic loss of P53 gene are two vi- tal genetic events in earlier stage of breast tumorigenesis.

我们还发现，〓和〓位点LOH均分布在乳腺浸润性导管癌、单纯癌、髓样癌及硬癌中，在浸润性小叶癌和某些特殊类型乳腺癌中全部为LOH阴性，上述位点LOH可能与某些组织学类型乳腺癌的发生有关。P53基因是乳腺癌形成过程中的一个热点基因，本研究对12例Ⅰ期乳腺癌组织标本中P53基因热点区域第5、6、7、8外显子点突变进行了测定，发现41.6％（5／12）的病人有P53基因一个或多个点突变，其中3例同时伴有〓位点LOH，表明P53基因点突变和等位基因缺失是发生在乳腺癌形成早期的一个重要遗传学事件。

To treat them implicitly as mutations, by analogy to biological evolution, merely evades the issue.

通过与生物进化的类比，将它们处理为突变形成的，只不过是在逃避问题。

The properties of light-adapted and dark-adapted BR D96N films and their transformation mechanism were studied by measuring and analyzing the kinetic absorption spectra of the sample under light illumination.

通过对菌紫质D96N基因突变形成的薄膜样品在光照下动态光谱的测定和分析，研究了此样品的光适应型、暗适应型特性及其之间的转化机制。

Neural stem cells have a strong self-renew mechanism and it can transform after a little break. Neural stem cells have a long term survival, which mean that it has more probability of wrong copy than mature cells. These cells are formed glioma stem cells in the end. The genes who adjust neural stem cells can express in glioma stem cells, which hold out glioma stem cells from neural stem cells. There is another presume that glioma stem cells come from differentiated cells. Through the gene break of these cells, they can obtain characteristics of stem cells, then form glioma stem cells.

神经干细胞具有很强的自我更新机制，获得较少突变即有可能恶性转化，而且干细胞存活时间较长，这意味着干细胞比成熟细胞发生细胞复制的错误几率更大，因外界环境的刺激而发生突变的机会更多，最终形成脑胶质瘤干细胞，同时调节神经干细胞增殖和自我更新的基因在脑胶质瘤的脑胶质瘤干细胞中也表达，这也是支持神经干细胞是脑胶质瘤干细胞来源的；也有推测认为它可能起源于已分化的细胞，由这些细胞突变发生去分化得来，并通过基因突变而获得了干细胞自我更新的特性，从而形成脑胶质瘤干细胞。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。