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1.
目的分析家蚕近交系IS-c108A的遗传纯度,为家蚕实验动物化的培育工作提供指导。方法应用经过筛选的20条随机引物对家蚕近交系IS-c108A(F10)的3个蛾区各30个个体和该近交系的亲本系统c108、对照实用化品种871各30个个体的基因组DNA进行RAPD扩增,计算个体间和蛾区间的相似系数及遗传距离。结果家蚕近交系IS-c108A(F10)的3个蛾区内的多态性带频率分别为1.807%、1.841%、1.841%,平均为1.830%;起点亲本c108个体间多态性带频率为7.207%,对照品种871个体间的多态性带频率为7.08%;而近交系IS-c108A与c108之间的多态性带频率为49.20%,c108和871品种之间的多态性带频率为58.33%。家蚕近交系IS-c108A10的3个蛾区内个体之间遗传相似系数的平均值分别为0.99581、0.99555、0.99551,总平均为0.99562。结论家蚕近交系IS-c108A(F10)已具有较高的遗传纯合度,家蚕具有易于获得高纯的有利条件。  相似文献   
2.
苎麻雄性不育系生化代谢和育性遗传研究   总被引:1,自引:0,他引:1  
用不同温度和日长处理盆栽材料,测试苎麻雄性不育系的温光反应;于雌雄性器官发育期取盆栽植株顶部展开叶往下数第7叶,分析不育系的生化代谢;根据杂交及自交后代育性分离情况,鉴定不育系的不育性遗传方式.结果如下高温加速营养生长,而短日促进生殖生长,短日高温明显加快不育系的发育进度,但高温的促进作用随日长增加而减弱,以至消失.不育系的叶片粗蛋白质、氨基酸含量比可育系减少,尤其是天门冬氨酸、谷氨酸、甘氨酸、胱氨酸、缬氨酸、苯丙氨酸和精氨酸减少明显,但游离脯氨酸含量增加.这些物质代谢的变化,可能是导致苎麻雄性不育的原因.不育系GS14-1、SS370、GSA-2、GS15-8和SS387等的不育性遗传与1对相对性状的遗传方式相符,已找到不育系的保持系和恢复系.  相似文献   
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从GenBank获取已公布的人及相应国家禽感染的H5N1禽流感病毒HA核酸和蛋白序列,用生物软件ClustalX1.83和MEGA4.0对HA基因序列和蛋白分析,构建HA核苷酸遗传进化树.结果表明,HA蛋白上再次出现既能与人又能与禽受体特异性结合的QNG;东南亚和东亚人感染毒株亲缘关系密切,西亚、南亚和非洲人感染毒株遗传距离近;进化树组成和HA蛋白关键位点氨基酸的变异,揭示多数国家的人感染的毒株与当地禽感染毒株高度同源,具有地域性特征,部分国家之间存在着病毒扩散现象.  相似文献   
5.
苯丙酮尿症分子遗传学研究进展   总被引:7,自引:0,他引:7  
张誌  何蕴韶 《遗传》2004,26(5):729-734
苯丙酮尿症是由于苯丙氨酸羟化酶基因突变引起的常染色体隐性遗传病。文章综述了苯丙酮尿症中的苯丙氨酸羟化酶基因的定位、结构、突变、调控以及突变基因的体外表达和苯丙氨酸羟化酶的三维结构特点等分子遗传学进展,阐述了苯丙氨酸羟化酶基因的突变对苯丙氨酸羟化酶的体外表达及其三维结构的影响, 以及部分基因型与表型相关的分子机制。 Abstract: Phenylketonuria(PKU) is one kinds of autusomal recessive disease caused by phenylalanine hydroxylase(PAH) gene mutation. This article reviews the recent molecular heredity progress on the phenylalanine hydroxylase gene’s orientation、structureand gene mutation and gene regulation. At same time, mutation gene in vitro expression and the character of 3D structure of PAH in PKU are involved. In this paper, also discussed the inflence of vitro expression and 3D protein structure by gene mutations and the molecular mechanism of the relationship between genotype and phenotype in PKU patient.  相似文献   
6.
采用套袋自交结实率和自然结实率为主,花粉育性和田间目测整株育性为辅的综合性状,判定新型细胞质雄性不育系马协A以及它与明恢63的杂种F_1、F_2和BF_1的植株育性,并以野败型珍汕97A作对照,比较研究了其不育性的遗传规律。结果表明,马协A与珍汕97A不育性的遗传均由两对基因控制,但新型细胞质雄性不育系马协A两对基因的作用方式与珍汕97A不同。前者F_2群体的育性分离符合9:3:3:1的比例,BF_1符合1:2:1的比例;后者相应群体则符合12:3:1和2:1:1的比例,两对基因间表现为显性上位。斯米尔诺夫检验也表明马协A/明恢63和珍汕97A/明恢63的F_2群体的结实率频率分布差异显著(P<0.01)。并讨论了细胞质雄性不育的遗传机理及分子基础。  相似文献   
7.
There is a high burden of mental and neurological disorders in Africa. Nevertheless, there appears to be an under-representation of African ancestry populations in large-scale genomic studies. Here, we evaluated the extent of under-representation of Africans in neurogenomic studies in the GWAS Catalog. We found 569 neurogenomic studies, of which 88.9% were exclusively focused on people with European ancestry and the remaining 11.1% having African ancestry cases included. In terms of population, only 1.2% of the total populations involved in these 569 GWAS studies were of African descent. Further, most of the individuals in the African ancestry category were identified to be African-Americans/Afro-Caribbeans, highlighting the huge under-representation of homogenous African populations in large-scale neurogenomic studies. Efforts geared at establishing strong collaborative ties with European/American researchers, maintaining freely accessible biobanks and establishing comprehensive African genome data repositories to track African genome variations are critical for propelling neurogenomics/precision medicine in Africa.  相似文献   
8.
Memory studies in biological systems distinguish three informational processes that are generally sequential—production/acquisition, storage, and retrieval/use. Identification of DNA as a storage form for hereditary information accelerated progress in that field. Assuming the path of successful elucidation in one memory field (heredity) to be heuristic for elucidation in another (brain), then progress in neuroscience should accelerate when a storage form is identified. In the 19th century Ewald Hering and Samuel Butler held that heredity and brain memory both involved the storage of information and that the two forms of storage were the same. Hering specified storage as ‘molecular vibrations’ but, while making a fuller case, Butler was less committal. In the 20th century, the ablation studies of Karl Lashley failed to identify unique sites for storage of brain information, and Donald Hebb's ‘synaptic plasticity’ hypothesis of distributed storage over a neuronal network won favor. In the 21st century this has come under attack, and the idea that brain and hereditary information are stored as DNA is advocated. Thus, albeit without attribution, Butler's idea is reinstated. Yet, while the case is still open, the synaptic plasticity and DNA hypotheses have problems. Two broad alternatives remain on the table. Long term memory is located: (1) in the brain, either in some other macromolecular form (e.g. protein, lipid) or in some sub-molecular form (e.g. quantum computing and ‘brain as holograph’ hypotheses) or (2) outside the brain. The suggestion of the medieval physician Avicenna that the brain ‘cupboard’ is bare—i.e. the brain is a perceptual, not storage, organ—is consistent with a mysterious ‘universe as holograph’ model. Understanding how Butler came to contribute could be heuristic for future progress in a field fraught with ‘fractionation and disunity’.  相似文献   
9.
The effects of hereditary and environmental factors upon the growth in stature of children living in Guatemala City has been studied. Heights at yearly examinations were fitted, by individual, to a double logistic curve in samples of Guatemalan and European children attending a private school in Guatemala City. These two samples differed genetically yet shared the same environment. Their growth was compared, by a multivariate analysis of the parameterized curves, to that of children from the Berkeley Growth Study, genetically similar to the European sample, yet living in different environments. The European children in Guatemala grew, before adolescence, more similar to Guatemalan and differed significantly from the Berkeley sample children. However, the amount of growth during the adolescent years experienced by the European children was similar to that of the Berkeley sample and differed from their Guatemalan counterparts.  相似文献   
10.
推导证明出有理真分式高阶导数的Q(n)公式,开发出双螺旋结构DNA分子的基因精简形式的数学模型,提出了生物杂交、测交遗传相对性状的数量计算方法,揭示出基因表达及其调控的微分定律,建立了微分定律的数学模型,给出了遗传信息系统基本结构的公式化诠释和推断的图解.该成果填补了遗传基本规律的理论空白,对生物遗传信息系统的结构研究和遗传工程问题的数学分析具有开拓性的意义.  相似文献   
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