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61.
Identification of a diverse mini‐core panel of Indian rice germplasm based on genotyping using microsatellite markers 下载免费PDF全文
Kapil K. Tiwari Anshuman Singh Sasmita Pattnaik Maninder Sandhu Sukhdeep Kaur Sourabh Jain Sushma Tiwari Shweta Mehrotra Mahender Anumalla Rashmita Samal Jyoti Bhardwaj Neha Dubey Vikrant Sahu Gayle A. Kharshing Patu K. Zeliang Kadiri Sreenivasan Pankaj Kumar Swarup K. Parida Sevanthi V. A. Mithra Vandana Rai Wricha Tyagi Pawan K. Agrawal Atmakuri R. Rao Arunava Pattanayak Girish Chandel Ashok K. Singh Ishwari S. Bisht Kangila V. Bhat Gundimeda J. N. Rao Jitendra P. Khurana Nagendra K. Singh Trilochan Mohapatra 《Plant Breeding》2015,134(2):164-171
Identification of a small core germplasm set representing the available genetic diversity is essential for its proper evaluation and subsequent utilization in rice improvement programmes. For constituting a small diverse mini‐core panel of Indian rice germplasm, a representative set of 6912 accessions drawn based on their geographic origin from the whole rice germplasm collection available in the National Gene Bank was genotyped using 36 microsatellite markers. Automated fragment analysis of amplicons yielded a total of 435 alleles, with an average 12.4 and range of 3–29 alleles per locus. Polymorphism information content (PIC) ranged from 0.08 (RGNMS190) to 0.86 (RM552) with an average of 0.528. Based on genotyping data, a mini‐core consisting of 98 genotypes was identified. Ninety‐four per cent of the alleles present in the core set were present in the mini‐core. The identified small but diverse panel will be useful for further intensive trait‐specific evaluation and utilization in allele mining. 相似文献
62.
新疆8个棉花品种(系)的指纹图谱分析 总被引:2,自引:0,他引:2
利用ISSR对8个新疆品种(系)进行指纹图谱构建。通过基因组多态性分析,从60条引物中筛选到11条扩增效果好的引物,用其中2条引物UBC809,UBC841建立8个品种的指纹图谱,统计品种鉴定的置信概率达到1/8388608。结果显示,ISSR分子标记技术对棉花品种的指纹图谱构建具有高效性和准确性。 相似文献
63.
Vine-1 retrotransposon-based sequence-specific amplified polymorphism for Vitis vinifera L. genotyping 总被引:1,自引:0,他引:1
The sequence‐specific amplification polymorphism (S‐SAP) method, derived from the amplified fragment length polymorphism (AFLP) technique, produces amplified fragments containing retrotransposon long terminal repeat ( LTR ) sequence at one end and a host restriction site at the other. The development and application of this procedure to the LTR of the Vine‐1 element from grapevine is reported. Two primers derived from one of the LTR sequences flanking the retrotransposon were used in combination with MseI degenerated primers on 15 grapevine accessions. S‐SAP results were compared with AFLP data. The heterozygosity and gene diversity values were higher for S‐SAP than for the AFLP procedure. Results show that S‐SAP amplification is effective in identifying polymorphisms and defining genetic distances among cultivars, and could be used for fingerprinting and for ‘Traminer’ clone identification. To the contrary Vine‐1 retrotransposon‐based S‐SAP was not able to distinguish ‘Pinot’ clones. 相似文献
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SCAR marker tagged to the alien leaf rust resistance gene Lr19 uniquely marking the Agropyron elongatum-derived gene Lr24 in wheat: a revision 总被引:3,自引:0,他引:3
A sequence characterized amplified region (SCAR) marker tagged to an Agropyron elongatum‐derived leaf rust resistance (Lr) gene Lr19 was validated on 18 known alien Lr gener in near‐isogenic lines (NILs) in the variety ‘Thatcher’, along with three wheat cultivers carrying Lr24 and two carrying Lr19. The marker was expressed only in the Lr24 lines confirming that the marker tagged the geneLr24. The monomorphic expression of the SCAR marker in 10NIL pairs for Lr19 and Lr24 revealed that each NIL pair possessed the same gene, Lr24. The donor parents used in the NIL pairs for Lr19 (‘Sunstar*6/C80‐1′) and Lr24 (‘TR380‐14*7/3Ag#14′) amplified the same fragment. Nonsegregation for leaf rust in the F2 population of the cross between the above donor parents confirmed the presence of the same gene in the two parents. Apparently, a genuine parent stock of ‘Sunstar*6/C80‐1’ was not involved in the development of the NIL pairs for Lr19 due to an improper maintence bredding protocol either at source or destination which went undetected in the absence of signs of virulence for either gene in the region. 相似文献
68.
壳斗科(Fagaceae)栗属(Castanea)植物的7个种分布广泛,不仅可用于木材生产,而且在坚果生产上也占有独特地位。基于形态学、同工酶、子叶储藏蛋白和RAPD数据,通过对分布于亚洲、欧洲和北美的栗属植物的遗传多样性研究表明中国板栗(Castaneamollissima)是世界栗属植物的原始种,长江流域是中国板栗的遗传多样性中心,土耳其是欧洲板栗的起源中心之一。在分子标记辅助育种方面,已发表了基于形态学、同工酶、RAPD和ISSR数据的两张栗属植物的遗传连锁图谱,其中一个是用欧洲板栗种内杂交后代F1全部单株构建的,另一张是用美洲板栗与中国板栗种间杂交后代F2单株构建的,并已经定位了3个假定的栗疫病抗性位点;并且证明在多年生木本果树上同工酶基因可通过连锁关系分析与形态基因整合为1个单一基因图而无需另外的杂交。从栗属植物中已分离纯化了包括可抑制HIV-1反转录酶活性的Mollisin在内的几丁质酶等抗真菌蛋白、胱氨酸蛋白酶抑制剂、热击蛋白、红血球凝集素、脱水素、花粉过敏原等功能蛋白质,并已经克隆了包括伤害应答基因在内的部分功能蛋白质相关基因。因此,作为具有独特性质的栗属植物,有必要开展更多的研究,就此本文对栗属植物遗传多样性、分子标记辅助育种和功能蛋白纯化和有关基因克隆等几方面的研究进展进行了总结,希望能位同行提供参考。 相似文献
69.
The gene Pi15 for resistance of rice to Magnaporthe grisea was previously mapped to a ≈0.7-cM region on chromosome 9. To further define the chromosomal region of the Pi15 locus, a contig spanning the locus was constructed, in silico , through bioinformatics analysis using a reference sequence of the cultivar 'Nipponbare'. One simple sequence repeat marker adopted from the International Rice Microsatellite Initiative and six candidate resistance gene (CRG) markers, developed from gene annotation of the reference sequence of the contig, were used for linkage analysis in a mapping population consisting of 504 extremely susceptible F2 plants. The Pi15 locus was delimited to a ≈0.5-cM region flanked by the markers CRG5 and CRG2 and co-segregated with the markers BAPi15782 , CRG3 and CRG4, which was physically converted to a 44-kb interval. 相似文献
70.
利用363对SSR标记分析了在我国小麦生产和育种中发挥了重要作用的11份国外引进品种和33份选育品种的遗传组成,旨在揭示国外种质对我国小麦品种改良的遗传贡献,指导种质资源引进和利用。国外种质包含了选育品种所发现等位变异的76.3%。与不同时期小麦品种等位基因多样性比较发现,国外种质的平均等位变异数最多(3.92),20世纪60年代(2.86)和70年代(3.01)基本一致,80年代有所升高(3.46)。品种间遗传距离比较与品种等位基因多样性结果相吻合。比较引进和选育品种在SSR位点的等位变异频率变化,发现至少在33个SSR位点,国外种质等位变异在我国小麦育种中被优先选择(该等位变异在引进和选育品种的分布频率均高于70%),其中一些位点已知与产量、生育期和抗病等性状密切相关。表明引进品种在以上基因组区域对我国小麦品种具有非常高的遗传贡献。 相似文献