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71.
采用CodonW1.4.2软件和CUSP程序,以普通羊肚菌(Morchella conica)全基因组蛋白质编码序列(coding sequence,CDS)为对象,解析了该菌的有效密码子数(effective number of codon,ENC)、密码子3个位点的 GC含量、相对同义密码子使用度(relative synonymous codon usage,RSCU)和高表达优越密码子。结果表明:普通羊肚菌全基因组密码子第2位密码子的 GC含量明显低于第1位和第3位,第3位密码子与第1位含量差异不大,分别为57.8%和56.8%,RSCU 值大于等于1的密码子总共35个,其中以 G 或 C 结尾的25个,占71.4%,确定了25个高表达优越密码子。 相似文献
72.
RAN Xu-hua CAO Si ZHANG Yao WEI Xiao-man WEN Xiao-bo NI Hong-bo ZHU Zhan-bo 《中国畜牧兽医》2015,42(5):1104-1109
Rotavirus is a major cause of acute diarrhea in both many kinds of young animals and children under 5 years old.Rotavirus NSP1, a 55 ku RNA binding protein, is the product of gene 5, which can subvert innate immune responses and be one of virulent determinant factors.According to the sequence in GenBank, specific primers targeting to NSP1 gene were designed and the gene was amplified by RT-PCR, following by being cloned into the pET-28a(+) vector.It showed that the full length of NSP1 gene was 1 473 bp, encoding 491 amino acids.The NSP1 shared the highest identity with WC3 strain.The recombinant protein was induced in E.coli Rosetta(DE3) by IPTG and was analyzed by SDS-PAGE and Western blotting.The results revealed that NSP1 recombinant protein existed in the form of inclusion body with the molecular weight of 55 ku.The purified recombinant protein could be recognized by His-tag antibody.This study laid the foundation for further research on the relationship between the intracytoplasmic location of NSP1 protein and its activity. 相似文献
73.
74.
长链酯酰辅酶A合成酶(ACSLs)是长链脂肪酸通过硫代酯化进而合成酰基辅酶A衍生物所必需的酶,也是脂肪酸代谢的第一步。哺乳动物ACSL家族由ACSL1、ACSL3、ACSL4、ACSL5和ACSL65个不同的成员组成,ACSL1是主要的异构体之一。为探讨黄羽肉鸡ACSL1基因作为腹脂性状分子标记的可行性,本实验采用PCR-直接测序技术对黄羽肉鸡ACSL1基因进行遗传多态性分析。结果显示:黄羽肉鸡ACSL1基因第17到第18外显子区域(1295 bp)SNPs位点较丰富,T32126C、C32013T、A31958G这3个位点的等位基因频率符合哈代-温伯格平衡,且A31958G突变位点、T32126C突变位点与腹脂重、腹脂率不相关,C32013T突变位点对鸡的腹脂重与腹脂率有显著影响,提示能够利用C32013T突变位点对黄羽肉鸡腹脂重进行分子标记辅助选择。 相似文献
75.
Nazgol Emrani Mario Hasler Dilan S. R. Patiranage Maldonado-Taipe Nathaly Elodie Rey Christian Jung 《Plant Breeding》2020,139(6):1190-1200
Quinoa offers a promising alternative for staple food, considering its outstanding nutritional value and tolerance to abiotic stresses. To develop breeding programmes in quinoa, a reliable crossing method for increasing the genetic variation is required. In the following study, we aimed to develop segregating populations in quinoa. We tested the efficiency of three different crossing methods (hand emasculation, warm water emasculation and no emasculation). Moreover we developed a two-stage selection strategy based on morphological traits and molecular markers for the selection of hybrid plants. We reported hand emasculation to be the most efficient crossing method, followed by warm water emasculation and no emasculation. Our results demonstrated that crosses in quinoa can be successfully performed, despite its complicated flower structure and high self-pollination rate. Additionally, we developed 30 segregating populations from crosses between accessions of different origins with varying phylogenetic relationship, which offers a promising perspective for quinoa breeding programmes in the future. 相似文献
76.
77.
为了探究不同年代的大丽轮枝菌(Verticillium dahliae Kleb.)菌株生物学特性和遗传多样性方面的差异,本文以我国黄河流域和长江流域主产棉区6个省的不同年代大丽轮枝菌菌株为研究对象,观察培养性状,测定致病类型(致病力、落叶型),同时采用ISSR指纹图谱分析其遗传多样性。结果显示,不同年代大丽轮枝菌之间菌丝生长速率无显著差异,但菌核型菌株所占比例有减少趋势;2007~2009年和2017年的菌株全部为落叶型菌株,而1983~2000年的菌株中落叶型菌株仅占28.6%,表明随着年代的推移,黄河流域和长江流域的落叶型菌株所占比例呈上升趋势;不同年代菌株之间致病力存在显著差异,1983~2000年、2007~2009年和2017年的菌株中强致病力类型菌株分别占21.4%、25.0%和38.9%,仅有的5株弱致病力类型菌株均为1983~2000年的菌株;与2000年后的菌株相比,1983~2000年的菌株,Nei′s基因多样性指数为0.205 1,Shannon信息指数为0.299 0,表现出更丰富的多样性,利用NTSYS软件和Structure软件对ISSR指纹图谱进行聚类分析,两种方法均将所有供试菌株分为4个类群,且聚类结果与致病力和不同年代之间均具有一定的相关性,与地理来源无明显相关性。本研究结果表明,过去30年间我国黄河流域和长江流域棉田黄萎病菌落叶型和强致病力类型菌株所占比例逐渐升高,且不同年代和不同致病力的菌株在遗传上有差异,为进一步探究大丽轮枝菌的遗传与进化奠定了基础。 相似文献
78.
【目的】随着不同棉种序列数据库的逐步完善以及高通量测序技术的发展,棉花单核苷酸多态性(Single nucleotide polymorphism,SNP)标记开发可利用的公共数据资源逐步增加。【方法】本研究基于陆地棉祖先基因组的现代种亚洲棉表达序列标签(Expressed sequence tag,EST)数据库,利用CAP3对亚洲棉EST数据库进行拼接。拼接获得7 187个重叠群(Contig),再利用Quality SNP软件进行SNP位点分析。【结果】在807条含有4条以上EST序列的Contig中查找到2 690个SNP位点。通过筛选次要等位基因频率大于30%的位点,获得953个可靠度较高的候选SNP,通过电子筛选,最终获得可用于陆地棉分析的SNP 149个,利用位点特异性聚合酶链式反应以及酶切扩增多态序列验证了EST-SNP的准确性。【结论】本研究证实基于亚洲棉EST数据库挖掘用于陆地棉研究的EST-SNP切实可行,并有望将EST-SNP用于陆地棉遗传图谱构建、重要性状的基因定位以及分子标记辅助育种。 相似文献
79.
Trevor J. Gilliland Paolo Annicchiarico Bernadette Julier Marc Ghesquière 《Grass and Forage Science》2020,75(3):227-241
Herbage production is regarded as having environment-friendly credentials. However, as the ruminant production it supports is facing major challenges on sustainability, environmental footprint and human health concerns, EU herbage cultivar testing must contribute to the solutions. Before new cultivars can be sold in a member state (MS) and gain EU-wide marketing, they must pass official tests to prove they are both novel (distinct, uniform and stable, DUS) with improved value for cultivation and use (VCU). Herbage species present specific challenges, as their allogamy imposes a wide within-cultivar variation that adds complexity to DUS tests and their “value” is only realized in ruminant produce. Current VCU systems measure production, chemical composition and disease/stress tolerances, often on large numbers of candidate cultivars, but prohibitive labour costs and logistics mean that animal intake, ruminant output or environmental benefits cannot be measured directly. Furthermore, some candidate cultivars with proven superior VCU fail DUS even though the non-distinct comparison is with a significantly lower performing registered cultivar. To resolve these problem cases, a “vmDUS” distinctness tool is proposed, which uses molecular markers but conforms to UPOV-declared principles. A short overview of current grassland research shows smart proxy measures of animal value can easily and quickly be adopted into an integrated pan-European (EU-VCU) test network. The proposed EU-VCU scheme will reallocate test resources to conduct these additional tests by placing MS in data sharing collaborations, while retaining their national listing authority. The benefits to all stakeholders from adopting these new testing procedures are considered. 相似文献
80.
《Veterinary microbiology》2015,175(2-4):185-194
Cyprinid herpesvirus 3 (CyHV3), also known as koi herpesvirus (KHV), can be subdivided primarily into European and Asian genotypes, which are represented by CyHV3-U or CyHV3-I and CyHV3-J, respectively. In this study, the whole genome sequence of a novel Chinese CyHV3 isolate (GZ11) was determined and annotated. CyHV3-GZ11 genome was found to contain 295,119 nucleotides with 52.9% G/C content, which is highly similar to those of published CyHV3-U, CyHV3-I, and CyHV3-J strains. With reference to CyHV3-U, CyHV3-I, and CyHV3-J, CyHV3-GZ11 was also classified into 164 open reading frames (ORF), which include eight repeated ORFs. On the basis of the 12 alloherpeviruses core genes, results from phylogenetic analysis showed that CyHV3-GZ11 had closer evolutionary relationships with CyHV3-U and CyHV3-I than with CyHV3/KHV-J, which were also supported by genome wide-based single nucleotide substitution analysis and the use of a series of developed molecular markers. This study was the first to reveal the presence of a distinct European CyHV3 genotype in East and Southeast Asia at a whole genome level, which will evoke new insights on exploring the origin, evolution, and epidemiology of the virus. 相似文献