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81.
传染性法氏囊病病毒的PCR引物设计与Internet检索分析 总被引:1,自引:0,他引:1
研究了传染性法氏囊病病毒(IBDV)A片断的cDNA的结构,并使用PrimerDesign引物设计软件,在VP5和VP2的重叠基因区设计了一对引物,各种IBDV毒株在此部位有非常高的同源性,在对引物进行Internet检索中得到了证实。经过对4种IBDV的疫苗标准毒株,1种野毒株,1例病鸡标本试检测,验证引物设计符合要求,具有良好的适应性和较高的灵敏度。 相似文献
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Inter simple sequence repeat (ISSR) polymorphism and its application in plant breeding 总被引:46,自引:0,他引:46
Inter simple sequence repeat (ISSR)-PCR is a technique, which involvesthe use of microsatellite sequences as primers in a polymerase chainreaction to generate multilocus markers. It is a simple and quick methodthat combines most of the advantages of microsatellites (SSRs) andamplified fragment length polymorphism (AFLP) to the universality ofrandom amplified polymorphic DNA (RAPD). ISSR markers are highlypolymorphic and are useful in studies on genetic diversity, phylogeny, genetagging, genome mapping and evolutionary biology. This review providesan overview of the details of the technique and its application in geneticsand plant breeding in a wide range of crop plants. 相似文献
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以沙田柚、强德勒柚、红江橙为材料,利用优化的柑橘ISSR体系,对100个ISSR引物进行了筛选.结果表明:28个引物能够扩增出2~12条稳定、清晰的条带,多态性条带为1~9条,多态率为25%~90%,其中P807,P808,P809,P810,P811,P812,P814,P815,P820,P821,P822,P826,P827,P830,P834,P835,P840,P845等18个引物在沙田柚和红江橙之间有差异,P812,P814,P815,P827,P834,P840等6个引物在沙田柚和强德勒柚之间有差异.用2个差异引物P827和P834可从36株沙田柚×强德勒柚杂交后代中鉴定出31株为真杂种,用P810,P811,P812,P835等4个引物可以把52株沙田柚×红江橙杂种后代全部鉴定出来,并且获得了一个适用于沙田柚和红江橙杂交后代鉴定分析的完全显性标记P810. 相似文献
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Jack Rojahn Dianne M. Gleeson Elise Furlan Tim Haeusler Jonas Bylemans 《水产资源保护:海洋与淡水生态系统》2021,31(4):990-997
- The presence of threatened or endangered species often strongly influences management and conservation decisions. Within the Murray–Darling Basin (MDB), Australia, the presence of threatened native fish affects the management and allocation of water resources. In New South Wales, these decisions are currently based on traditional fisheries data and a predictive MaxEnt model. However, it is important to verify the model's predictive power given the implication it may have, but this requires methods with a high detection sensitivity for rare species.
- Although the use of environmental DNA (eDNA) monitoring, in particular eDNA metabarcoding, achieves a higher detection sensitivity compared with traditional methods, earlier surveys in the MDB have shown that the highly abundant and invasive common carp (Cyprinus carpio) can reduce detection probabilities for rare species. Consequently, a polymerase chain reaction (PCR) blocking primer designed to block the amplification of carp eDNA could increase the detection probabilities for rare native species while simultaneously reducing the required sampling effort and survey costs. Although PCR blocking primers are often used in ancient DNA and dietary studies, no aquatic eDNA metabarcoding study to date has evaluated the potential benefits of using PCR blocking primers.
- A laboratory and field-based pilot study was used to address this knowledge gap and assess the impact of a blocking primer, targeting cyprinid fishes (including carp), on the detection probabilities of native species and the minimum sampling effort required.
- Results showed that the inclusion of the blocking primer increased the detection probabilities for native species by 10–20% and reduced the minimum required sampling effort by 25–50%. These findings provide important insights into possible methods for optimizing eDNA metabarcoding surveys for the detection of rare aquatic species.
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【目的】 研究玉米杂种优势类群划分高多态SSR引物筛选。【方法】 遴选均匀分布在玉米10个连锁群上160对SSR引物,在104份玉米自交系DNA中扩增,根据引物的染色体分布和PIC值,分别取40、30、20和10对高多态引物建立4套新引物体系,检测104份自交系的分类效果。【结果】 (1)160对引物中的63对引物带型稳定,多态性高,最高PIC值0.762 3,高于过去常用核心SSR引物,63对引物中过去常用核心SSR引物仅保留40%左右;(2)4套引物体系中,40和30对引物体系的分类结果与已知自交系类群高度吻合,20对体系与40对体系比较具90.5%一致性,10对体系与40对体系比较的一致性81.0%;(3)40对体系分类104份材料为5大类群,分别是瑞德、改良瑞德、兰卡斯特、黄改和和旅大红骨,与目前国内利用的优势群划分结果一致,也能鉴别出每个群中亲缘关系最远的亚群是相近群间二环系来源的混合基因型;(4) 各群的代表自交系是单一遗传结构成分,亚群是多遗传结构成分。【结论】 部分SSR引物的多态性在新自交系中会出现下降,建立的新的40对引物体系有精确的分类功能,可应用于类群划分,20对体系的分类精确性稍低,但检测工作量减半,在批量材料分类中有利用价值。 相似文献
89.
Lucia Liviero Elena Maestri Mariolina Gulli Eviatar Nevo Nelson Marmiroli 《Genetic Resources and Crop Evolution》2002,49(2):133-144
Long primer PCR (LP-PCR) markers specifically targeted to sequences involved in the response to abiotic stress were utilised to analyse genetic variation within and among wild barley populations from Israel.Populations were sampled in locations reflecting a wide range of habitats and the potential correlation between genetic variation and ecogeographic parameters was examined. A high level of polymorphism was observed. Most of the variability was due to differences within populations, however a substantial portion of genetic variation (36%) could be attributed to differences among populations, indicating local adaptation of genotypes to microclimatic conditions. Moreover, clustering and ordination techniques showed that genotypes grouped together according to their area of origin and were separated on thebasis of ecogeography, chiefly by a combination of temperature, altitude and rainfall variables. Finally, 28% of the polymorphic PCR fragments were significantly correlated with ecogeographic parameters. Our results demonstrate the effectiveness of PCR-based molecular markers targeted to environmentally regulated genes in detecting useful variation andthus in monitoring the impact exerted by adaptation to the environment ongenetic differentiation. 相似文献
90.
旨在筛选出适合于甜菜分子生物学实验的SSR核心引物,为后续构建甜菜指纹图谱及遗传多样性分析奠定重要基础。本文利用4种不同的甜菜种质资源和4个不同的甜菜品种,对基于甜菜全基因组编码区序列设计的247对SSR引物进行了初步筛选。结果表明,247对引物中绝大多数引物没有多态性或者多态性不好,只有27对引物具有较高的多态性,这27对引物总共扩增出103条带,其中多态性条带95条,多态性比率为90.43%。这些引物多态性信息量(PIC)范围为0.549~0.983,平均每一对引物的PIC值为0.841。试验结果表明虽然经过了电子PCR的筛选,想要找到合适的甜菜SSR引物依然比较困难,说明甜菜的遗传基础比较狭窄。这27对SSR引物适用于甜菜分子标记,为甜菜品种标准化鉴定体系的大规模构建和应用奠定了重要基础。 相似文献