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161.
Previous studies showed that the yellow seed color gene of a yellow mustard was located on the A09 chromosome. In this study, the sequences of the molecular markers linked to the yellow seed color gene were analyzed, the gene was primarily mapped to an interval of 23.304 to 29.402M. Twenty genes and eight markers’ sequences in this region were selected to design the IP and SCAR primers. These primers were used to screen a BC8S1 population consisting of 1256 individuals. As a result, five IP and five SCAR markers were successfully developed. IP4 and Y1 were located on either side of the yellow seed color gene at a distance of 0.1 and 0.3 cM, respectively. IP1, IP2 and IP3 derived from Bra036827, Bra036828, Bra036829 separately, co-segregated with the target gene. BLAST analysis indicated that the sequences of newly developed markers showed good collinearity with those of the A09 chromosome, and that the target gene might exist between 27.079 and 27.616M. In light of annotations of the genes in this region, only Bra036828 is associated with flavonoid biosynthesis. This gene has high similarity with the TRANSPARENT TESTA6 gene, Bra036828 was hence identified as being the gene possibly responsible for yellow seed color, in our research. 相似文献
162.
Carotenoids are not only important to the plants themselves but also are beneficial to human health. Since citrus fruit is a good source of carotenoids for the human diet, it is important to study carotenoid profiles and the accumulation mechanism in citrus fruit. Thus, in the present paper, we describe the diversity in the carotenoid profiles of fruit among citrus genotypes. In regard to carotenoids, such as β-cryptoxanthin, violaxanthin, lycopene, and β-citraurin, the relationship between the carotenoid profile and the expression of carotenoid-biosynthetic genes is discussed. Finally, recent results of quantitative trait locus (QTL) analyses of carotenoid contents and expression levels of carotenoid-biosynthetic genes in citrus fruit are shown. 相似文献
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为了建立健全产品质量安全风险管理体系,加强产品质量安全风险预警的要求,同时最大程度地利用过去成功的风险评估案例,构建了基于案例推理的产品质量安全风险评估系统。针对某种产品,根据专家的知识建立风险评估指标体系,并将每个评估指标赋权重,计算与案例库中的各个案例相似度,寻找出最大相似度案例,据此,辅助相关人员对目标案例进行风险分析与评估。 相似文献
166.
J. P. Emmet‐Booth P. D. Forristal O. Fenton B. C. Ball N. M. Holden 《Soil Use and Management》2016,32(4):623-634
Soil structure forms a key component of soil quality, and its assessment by semi‐quantitative visual soil evaluation (VSE) techniques can help scientists, advisors and farmers make decisions regarding sampling and soil management. VSE techniques require inexpensive equipment and generate immediate results that correlate well with quantitative measurements of physical and biochemical properties, highlighting their potential utility. We reviewed published VSE techniques and found that soils of certain textures present problems and a lack of research into the influence of soil moisture content on VSE criteria. Generally, profile methods evaluate process interactions at specific locations within a field, exploring both intrinsic aspects and anthropogenic impacts. Spade methods focus on anthropogenic characteristics, providing rapid synopses of soil structure over wider areas. Despite a focus on structural form, some methods include criteria related to stability and resiliency. Further work is needed to improve existing methods regarding texture influences, on‐farm sampling procedures and more holistic assessments of soil structure. 相似文献
167.
经过多年探索和发展,封闭型植物工厂无论在材料、装置和技术都取得了快速进步,生产产量成数倍增长。在介绍发展封闭型植物工厂必要性的基础上,着重分析了封闭型植物工厂的发展现状、设施分类、栽培形式选择、栽培技术选择,最后指出了存在的问题,并对未来的封闭型植物工厂外部设施及其栽培技术进行了展望。 相似文献
168.
Sulfated polysaccharides produced by microalgae, which are known to exhibit various biological activities, may potentially serve as natural antioxidant sources. To date, only a few studies have examined the antioxidant bioactivity of red microalgal polysaccharides. In this research, the effect of different salts on the antioxidant activities of two red microalgal sulfated polysaccharides derived from Porphyridium sp. and Porphyridium aerugineum were studied in a soy bean-based infant milk formula. Salt composition and concentration were both shown to affect the polysaccharides’ antioxidant activity. It can be postulated that the salt ions intefer with the polysaccharide chains’ interactions and alter their structure, leading to a new three-dimensional structure that better exposes antiooxidant sites in comparison to the polysaccharide without salt supplement. Among the cations that were studied, Ca2+ had the strongest enhancement effect on antioxidant activities of both polysaccharides. Understanding the effect of salts on polysaccharides’ stucture, in addition to furthering knowledge on polysaccharide bioactivities, may also shed light on the position of the antioxidant active sites. 相似文献
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基于GIS的土壤肥力质量综合评价——以天然云冷杉针阔混交林为例 总被引:2,自引:1,他引:1
以吉林汪清林业局金沟岭林场中41块天然云冷杉针阔混交林样地为对象,采用主成分-聚类分析,结合GIS技术,对该区域土壤肥力质量进行综合评价。结果表明,按主成分-聚类分析结果将41块样地分为4类:第1类土壤肥力质量综合得分为11.17~18.86(优),包括5块样地;第2类土壤肥力质量综合得分为3.01~7.44(良),包括8块样地;第3类土壤肥力质量综合得分为-6.97~1.27(一般),包括24块样地;第4类土壤肥力质量综合得分为-12.40~-9.63(差),包括4块样地。然后采用Arc GIS软件对综合得分进行普通Kriging插值,其标准均方根预测为0.9544,在1的附近,这基本达到插值精度的要求。从生成的研究区土壤肥力质量综合得分空间分布图来看,森林土壤肥力质量由西向东呈现先降低后升高的趋势;由北向南,森林土壤肥力质量变化幅度逐步减小,表明研究区南部土壤肥力质量变化较北部均匀。就研究区的整体土壤肥力质量而言,土壤肥力质量中等以上(优,良,一般)样地数占所研究区样地总数比例为90.24%,表明所研究区森林土壤肥力质量整体处于良好水平。 相似文献