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61.
BACKGROUND: The occurrence of carboxylic acid amide (CAA)‐fungicide‐resistant Plasmopara viticola populations is becoming a serious problem in the control of grapevine downy mildew worldwide. RESULTS: The authors have developed a method, which utilises PCR‐RFLP, for the rapid detection of resistance to the CAA fungicide mandipropamid in P. viticola populations. With this method, a glycine‐to‐serine substitution at codon 1105 of the cellulose synthase gene PvCesA3 of CAA‐fungicide‐resistant P. viticola was easily detected, although no resistant P. viticola was detected from 398 isolates in Japan. CONCLUSION: It is proposed that the PCR‐RFLP method is a reliable tool for the rapid detection of CAA‐fungicide‐resistant P. viticola isolates. Only 4 h was required from the sampling of symptoms to the phenotyping of fungicide resistance. Copyright © 2011 Society of Chemical Industry 相似文献
62.
Debora Giorgi Renato D'Ovidio Oronzo A. Tanzarella Enrico Porceddu 《Genetic Resources and Crop Evolution》2002,49(2):145-151
The phylogenetic relationships among theAegilops species belonging to the Sitopsis section were investigated using RFLP (restriction-fragment-length polymorphism) analysis. Twenty-five probes, each of which hybridised to oneor more restriction fragments located in the B-genomechromosomes of cultivated wheats, were used. At least one and in most cases two fragments were located in every B genome chromosome arm. Adendrogram derived from a cluster analysis of the complete RFLP dataset showed a subdivision of the species belonging to the Sitopsis section into one group comprising the species of the Truncata subsection and another group comprised of the species of theEmarginata subsection. Dendrograms also were produced using RFLP data from loci located in different combinations of only three chromosomes, and some of these showed different subdivisions of the species. This demonstrates the importance in obtaining reliable classification data of using probes that detect loci evenly distributed in the genome and located in each chromosomearm. 相似文献
63.
This paper describes the identification and utilisation of a sequence-characterised amplified region (SCAR) marker specific for the Trichoderma virens biocontrol isolate GV4. The marker was developed from a RAPD-PCR amplification product unique to isolate GV4. When used as a hybridisation probe in Southern blot analysis, it hybridised to the DNA of the species T. virens alone and not to that of other Trichoderma species or closely related genera Gliocladium and Verticillium. The marker also produced a GV4-specific RFLP, distinguishing it from other T. virens isolates when probed to blots with HindII, BamHI or PstI genomic DNA digests. Primers designed from the sequence of the RAPD marker produced a diagnostic amplification product of 346 bp for GV4 alone, distinguishing it from all other test isolates. With the exception of one, test isolates did not produce an amplification product with the SCAR primers. The exception was a single Verticillium psalliotae isolate (ICMP5509) that produced a product of approx. 400 bp that was easily distinguished from the 346 bp product of GV4. The reliability of the SCAR-based diagnostic test was further improved with the introduction of a positive PCR reaction control to each test, achieved by converting the test to a duplex PCR system. Two universal primers flanking the two ITS and the 5.8S region of the ribosomal gene complex were introduced to each reaction to provide a test for PCR reaction inhibitors to eliminate false negatives in the diagnosis. Amplification of this multi-copy genomic region did not reduce diagnostic sensitivity of the single copy SCAR marker. To further increase the sensitivity of detecting GV4 propagules while maintaining a fast sample assessment assay, soil was amended with cornmeal, as a nutrient source, and a mix of antibiotics to favour Trichoderma growth. The soil mix was subsequently incubated for 5 d before total DNA was extracted. Under these conditions, the duplex soil PCR assay detected GV4 down to a concentration of 10 spores g−1 soil in non-sterile agricultural field soil. This study is the first to report the use of a duplex-PCR diagnostic bioassay for a species within the Hypocrea/Trichoderma genus. 相似文献
64.
The RFLP technique has been employed to investigate phylogenetic relationships between species of the Hedysarum genus. Homologous DNA probes were used to generate patterns from a set of the Mediterranean group. The degree of band sharing was used to estimate genetic distances between species and to draw phylogenetic trees. These are in good agreement with phylogeny based on morphological and isozyme markers, but contain novel insights. The results are discussed in the context of current work in molecular biosystematics in Hedysarum complex. Attempts made in this approach to access the extent of variability at the DNA level occurring with the domestication process have been investigated. With the availability of the tested probes, it has been assumed that the genetic structure is not affected by the domestication process. 相似文献
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传染性支气管炎病毒中国地方分离株RFLP基因分型的研究 总被引:5,自引:1,他引:4
为初步确定我国不同地区流行的传染性支气管炎病毒(IBV)的基因分型,对分离自国内8个不同地域疫区的IBVQD、GZ、ZZ、TJ、DL、YC、JS1和JS2及参考株M41、H52和T的S1基因RT-PCR扩增cDNA进行HaeⅢ的RFLP分析。结果,QD与MD41、H52同属Massachussete基因型,GZ、ZZ、YC与T的基因型相同,DL、JS1和JS2则表现为各自独立的基因型,而TJ则为DL和T2种基因型毒株的混合感染,表明我国的广大地域内存在着Mass基因型、T基因型和可能的变异株IBV的流行。 相似文献
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Plant parasitic nematodes of the family Trichodoridae cause substantial yield losses in many agricultural crops. Rapid and accurate identification of trichodorids to the species level is critical for selection of appropriate measures for control. This study analysed 99 sequences of the D2–D3 expansion segments of the 28S rRNA gene and 131 sequences of the 18S rRNA gene from the stubby nematodes belonging to the genera Nanidorus, Paratrichodorus and Trichodorus. Species delimiting was based on the integration of morphological identification, which is not provided in the present article, and molecular‐based phylogenetic inference and sequence analysis. Twenty‐two valid species and several species complexes were identified among nematodes included in the analysis. PCR‐RFLPs of the partial 18S rDNA and the D2–D3 expansion segments of the 28S rDNA were tested and proposed for identification of these nematodes. Gel PCR‐RFLP profiles and tables with restriction fragment lengths for several diagnostic enzymes are provided for identification. Some problems of taxonomy and phylogeny of nematodes of the family Trichodoridae are also discussed. 相似文献
70.
脂蛋白脂酶(LPL)是机体脂质和脂蛋白代谢的关键酶,在脂质代谢、转运和能量代谢方面发挥着重要作用,影响着动物的生长发育。为探讨湘西黄牛LPL基因的分子遗传特征和寻找与生长性状相关的分子标记,采用PCR产物测序的方法检测了湘西黄牛LPL基因的SNP位点,并进行了LPL基因exon 5的g.365458G>A位点进行了群体遗传多态与生长性状的关联分析。SNP检测结果表明,LPL基因在Intron 4上新发现了3个SNP(g.365186A>C、g.365248C>T和g.365249C>T),在exon5的182 bp处检测到了1个SNP(g.365458G>A)。g.365458G>A位点的多态性检测结果表明,g.365458G>A位点存在AA、AG和GG 3种基因型,呈中度多态,且达到了Hardy-Weinberg平衡状态。多态性与生产性状的相关性分析结果表明,湘西黄牛AA基因型个体的体高和胸围显著大于GG基因型个体(P<0.05),AA基因型个体的体长和体重极显著大于GG基因型个体(P<0.01)。A等位基因对湘西黄牛的体高、体长、胸围和体重都为正效应,而G等位基因都为负效应。推测LPL基因exon5的g.365458G>A位点有可能作为湘西黄牛生长性状的分子遗传标记位点。 相似文献