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排序方式: 共有6947条查询结果,搜索用时 15 毫秒
81.
Ghada Baraket Ahmed Ben Abdelkrim Olfa Saddoud Khaled Chatti Messaoud Mars Mokhtar Trifi Amel Salhi-Hannachi 《Scientia Horticulturae》2010
The trnL (UAA) intron and the intergenic spacer between the 3′ exon of trnL (UAA) and trnF (GAA) sequences were used as genetic markers for differentiating Ficus carica cultivars and establishing refined genetic relationships. The study was based on 20 fig cultivars, collected from south and centre of Tunisia. Since, the intron was thought to be more variable among close relatives than is the chloroplast spacer. The size of these non-coding regions varied from 554 to 589 and from 989 to 1022 bases pairs for the intron and the combined sequences correspondingly. The average of GC content was 33.9% and 34.6% in the intron and the combined intron and spacer respectively. High values of A + T contents were detected in both data sets and may explain the high proportions of transversions founded. The observed variation pattern of plastid DNA provides evidence of an important genetic diversity. The overall transition/transversion bias (R) was 0.202 in the intron and 0.27 in the combined regions. The RI index of 0.592 indicates that these combined sequences have clearly more homoplasy then the intron (RI = 0.705) and spacer (RI = 0.777) sequences separately. Phylogenetic trees were generated based on maximum parsimony (MP) and neighbor-joining (NJ) analysis of the chloroplast sequences data. Results proved that a typically continuous genetic diversity characterizes the local fig germplasm. In fact, relationships inferred from the cpDNA analysis suggest several clades, which do not show geographical or tree sex correspondence. Although the level of apparent diversity is considerable, we may conclude that non-coding regions of chloroplast genome provide a new and practical opportunity to evaluate genetic diversity and to discriminate fig cultivars. Revealed cytoplasmic DNA markers are reliable to elaborate a molecular data base to conduct management and breeding programs on local fig germplasm. 相似文献
82.
野生大豆遗传多样性研究Ⅰ4个天然居群等位酶水平的分析 总被引:7,自引:0,他引:7
本文采用水平淀粉凝胶电泳技术对分布于北京、山东和大连4个野生大豆天然居群共计120个体进行了等位酶水平遗传多样性分析。7个酶系统13个等位酶位点的检测表明,该地区野生大豆天然居群遗传变异水平较高,多态位点比率P=69.20,等位基因平均数A=1.77,平均期望杂合度He=0.133,居群间有较明显的遗传分化,基因分化系数Gst=0.391,即有39.1%的遗传变异存在于居群间。本文结果表明该地区遗 相似文献
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85.
I. Halila M. J. Cobos J. Rubio T. Millán M. Kharrat M. Marrakchi J. Gil 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(1):87-92
A second gene conferring resistance to the chickpea wilt pathogen, Fusarium oxysporum f. sp ciceris race 0, has been mapped to linkage group 2 (LG2) of the chickpea genetic map. Resistance to race 0 is controlled by two genes
which segregate independently; one present in accession JG62 (Foc0
1
/foc0
1
) and mapping to LG5 and the second present in accession CA2139 (Foc0
2
/foc0
2
) but remaining unmapped. Both genes separately confer complete resistance to race 0 of the wilt pathogen. Using a Recombinant
Inbred Line (RIL) population that segregated for both genes (CA2139 × JG62) and the genotypic information provided by two
markers flanking Foc0
1
/foc0
1
ten resistant lines containing the resistant allele Foc0
2
/foc0
2
were selected. Genotypic analysis using these ten resistant lines paired with ten susceptible RILs, selected in the same
population, revealed that sequence tagged microsatellite sites (STMS) markers sited on LG2 were strongly associated with Foc0
2
/foc0
2
. Linkage analysis, using data from two mapping populations (CA2139/JG62 and CA2156/JG62), located Foc0
2
/foc0
2
in a region where genes for resistance to wilt races 1, 2, 3, 4 and 5 have previously been reported and which is highly saturated
with tightly-linked STMS markers that could be used in marker-assisted selection (MAS). 相似文献
86.
87.
苜蓿新品系Dy-2006亲缘关系的SSR分析 总被引:1,自引:0,他引:1
应用SSR分子标记对苜蓿新品系Dy-2006等6个苜蓿品种(品系)亲缘关系进行了分析.8对SSR引物共扩增出128个位点,106个位点显多态性,多态位点比率82.81%;不同苜蓿品种(品系)SSR多态性百分率存在一定差异,在32.81%~45.31%之间.遗传相似度(F)和遗传距离(D)的变化分别范围在0.9062~0.9689和0.0326~0.0762.聚类分析结果显示,新品系Dy-2006与龙牧801亲缘关系相对较近,与阿尔冈金亲缘关系较远,并与其它供试品种存在一定差异,为一个相对独立的品系. 相似文献
88.
乌龙茶种质资源种群遗传多样性AFLP评价 总被引:18,自引:1,他引:18
以银染法AFLP分子标记技术用5对引物组合对来自福建武夷山市、安溪县、台湾省和广东潮安县45份乌龙茶品种资源进行遗传多样性分析。结果表明,5对引物扩增出208条多态性条带,多态性为92.03%;最大遗传距离为0.481,最小遗传距离为0.124,种质资源间遗传多样性估值较高,达0.311。按照地理分布分组分析表明,种群内遗传多样性以武夷山最高,其次为安溪乌龙茶种质资源,以台湾的乌龙茶种质资源遗传多样性最小;种群间遗传相似性,以武夷山与安溪种群间最高,达0.9505,以台湾和潮安县类型间的相似性最低,相似性系数为0.77。构建的种间和种群间进化树表明,可将45份乌龙茶品种划分为二大类型,福建类型和广东潮安类型。结合种群间相似系数,提出乌龙茶种质资源与其加工工艺的演化路径是一致的,也是由武夷山向安溪再向台湾传播。 相似文献
89.
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