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121.
122.
[目的]脂肪酸合成酶(Fatty acid synthase,FASN)是影响哺乳动物脂肪酸合成的关键酶,但有关水牛FASN基因的群体遗传组成特征还不清楚。[方法]本研究采用PCR产物直接测序法和PCR-SSCP方法对88头河流型和122头沼泽型水牛、54头牦牛和40头大额牛FASN基因外显子37进行群体变异检测,并结合已发表的牛科物种序列进行生物信息学分析。[结果]结果表明,仅在水牛中发现2个SNP位点,为c.6363CT和c.6372CT,均为同义替换。河流型和沼泽型水牛共享这2个SNP位点,但它们在两类水牛中的群体遗传组成不同。确定水牛特有的核苷酸位点3个,即c.6183A,c.6255T和c.6394A,其中c.6394A导致水牛FASN蛋白第2132位氨基酸与其它牛科物种不同,在水牛中为M而其它牛科物种中为V;山羊特有的位点2个,为c.6189A和c.6267T。普通牛、山羊和绵羊中具有异义替换SNP位点,分别为1个、3个和7个。普通牛的异义替换SNP位点c.6365GA对蛋白质功能影响不显著(subPSEC-3);山羊的这些异义替换SNP位点c.6296TC、c.6301CT和c.6341TC对其蛋白质功能影响均有显著影响(subPSEC-3);绵羊7个异义替换SNP位点中的2个,即c.6286AC和c.6406AG对FASN功能有显著影响(subPSEC-3)。[结论]这些核苷酸差异引起的氨基酸差异可能引起不同牛科物种间FASN功能的差异。  相似文献   
123.
乳酸菌基因组学研究现状   总被引:3,自引:3,他引:0  
作者对乳酸菌基因组学的研究现状,包括乳酸菌基因组测序及基本特征、乳酸菌基因代谢特点、重要的功能基因等方面进行了概述。  相似文献   
124.
Remarkable progress has been made towards a deeper understanding of mosquito biology since the completion of the Anopheles gambiae Giles genome project. Combined with the development of efficient transgenic technologies for genetic modification of major vector species and the availability of powerful molecular, genetic and bioinformatics tools, this is allowing the identification of genes involved in mosquito biological functions crucial to malaria transmission, ranging from host-seeking behaviour and innate immunity to insecticide resistance. Moreover, population genetic studies are beginning to elucidate the complex structure of vector populations. Finally, novel methods for malaria control are emerging that are based on the use of genetically modified mosquitoes either to interrupt the journey of the Plasmodium parasite within its insect host or to suppress those mosquito species that function as vectors for parasite transmission.  相似文献   
125.
Allelopathy studies the interactions among plants, fungi, algae and bacteria with the organisms living in a certain ecosystem, interactions that are mediated by the secondary metabolites produced and exuded into the environment. Consequently, allelopathy is a multidisciplinary science where ecologists, chemists, soil scientists, agronomists, biologists, plant physiologists and molecular biologists offer their skills to give an overall view of the complex interactions occurring in a certain ecosystem. As a result of these studies, applications in weed and pest management are expected in such different fields as development of new agrochemicals, cultural methods, developing of allelopathic crops with increased weed resistance, etc. The present paper will focus on the chemical aspects of allelopathy, pointing out the most recent advances in the chemicals disclosed, their mode of action and their fate in the ecosystem. Also, attention will be paid to achievements in genomics and proteomics, two emerging fields in allelopathy. Rather than being exhaustive, this paper is intended to reflect a critical vision of the current state of allelopathy and to point to future lines of research where in the authors' opinion the main advances and applications could and should be expected.  相似文献   
126.
RNA干拢技术是近几年发展起来的一种新技术,以其特异性、高效性对特定基因进行有效沉默。本文主要对siRNA的作用机制及应用做一简要概述。  相似文献   
127.
Plants and plant crops have always been, and will continue to be, of vital importance for humankind. They are an essential source of food, feed, raw materials, energy and pleasure. One of the main concerns in agriculture has always been to improve the quality of seed. Today, at the beginning of the 3rd Millennium, agriculture is confronted with a wide range of complex challenges. With diminishing availability of farming land, climatic changes and the threat of declining water resources, the task is to meet the growing demand for food, feed, fibre, fuel, industrial products and products based on ‘functional’ plants. Future‐oriented, knowledge‐based and added‐value agriculture will have to become reality. This will mean reduced use and redisposition of resources – in other words, ‘Do more with less!’ Within this context, the possibilities offered by efficiency developments in conventional seed breeding, supported by gene technology and plant genomic research, will improve the prospects of being able to use our limited natural resources to best effect in the 21st Century. The appropriate use and timely development of these important aspects will ensure sustainable production of food, feed, fibre, fuel and industrial products in the future.  相似文献   
128.
Some novel concepts of chemomics/molomics are proposed including hydrocarbomics, alcophenomics, carboxomics, pepitomics, metabonomics, etc. like genomics, protomics and glycomics in bioomics. Some examples are given to demonstrate the chemomics and/or molomics methodology and technology based chemoinformatics and bioinformatics and their wide applications in Chemistry and Biology.  相似文献   
129.
以凯氏定氮法测定“9409”饲用玉米的粗蛋白质为91.9g/kg。用Beckman 121型氨基酸分析仪测定其18种氨基酸含量(88.3252g/kg)占粗蛋白质含量的96.11%,13种必需氨基酸含量为4.3731g/kg。以90日龄未取盲肠公鸡测定中的氨基酸真可利用率在84.65%~96.21%。以蛋鸡和肉仔鸡理想蛋白质为模型,计算氨基酸平衡性指数,表明饲用玉米是家禽的良好蛋白源。  相似文献   
130.
检测由遗传修饰引起的非期望效应是进行转基因作物安全性评价的一项重要内容.以“实质等同性”概念为基础的评价方法,重点对转基因作物和非转基因亲本中的关键性成分进行定性、定量分析和比较难以充分考虑到一些不可预见因素的发生.“组学”技术通过对转基因作物的整个功能基因组、蛋白质组以及代谢组进行分析,将结果与非转基因亲本进行比较,完善了目前所广泛采用的以“实质等同性”概念为基础的定向方法.“组学”技术是很有潜力的.综述介绍了功能基因组学、蛋白质组学和代谢组学所用技术的原理和方法,重点讨论了这三大“组学”技术在评价转基因作物非期望效应中的应用和局限性,介绍了转基因食品食用安全性评价中非期望效应检测方面的最新进展.  相似文献   
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