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近年来,中国非常规军事突发事件频发,传统的"预测—应对"应急处置模式遇到了前所未有的挑战,构建"情景—应对"型非常规军事突发事件应急处置智能信息服务理论体系成为非常规军事突发事件应急处置领域的重要研究内容。对军事突发事件情景数据进行了分析,从用户数据、项目数据和军事突发事件情景数据3个维度建立了军事突发事件信息服务情景数据模型,为军事突发事件应急处置信息服务研究奠定了基础。 相似文献
73.
Rongbo Wang Shuzhun Chen Bowen Zheng Peiqing Liu Benjin Li Qiyong Weng Qinghe Chen 《Forest Pathology》2019,49(5)
Taxus chinensis is a valuable tree with uses for timber, medicinal, ornamental and landscape purposes. Most importantly, it is a source of the anti‐cancer drug paclitaxel. In 2016, needle spot disease was observed on T. chinensis in Fujian Province of China. Five isolates of similar morphology were isolated from diseased samples. The pathogen was identified as Neopestalotiopsis clavispora based on morphological and cultural characteristics and confirmed by sequence analysis of the internal transcribed spacer region (ITS) and the large subunit ribosomal RNA gene (LSU). The pathogenicity of the isolates was confirmed by fulfilling Koch's postulates. To the best of our knowledge, this is the first report to indicate that the causal agent of needle spot disease on Chinese yew in China is N. clavispora. 相似文献
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Hongchang Zhao Shaohua Zhu Tingting Guo Mei Han Bowen Chen Guoyan Qiao Yi Wu Chao Yuan Jianbin Liu Zengkui Lu Weibo Sun Tianxiang Wang Fanwen Li Yajun Zhang Fujun Hou Yaojing Yue Bohui Yang 《Journal of animal science》2021,99(9)
To investigate single nucleotide polymorphism (SNP) loci associated with yearling wool traits of fine-wool sheep for optimizing marker-assisted selection and dissection of the genetic architecture of wool traits, we conducted a genome-wide association study (GWAS) based on the fixed and random model circulating probability unification (FarmCPU) for yearling staple length (YSL), yearling mean fiber diameter (YFD), yearling greasy fleece weight (YGFW), and yearling clean fleece rate (YCFR) by using the whole-genome re-sequenced data (totaling 577 sheep) from the following four fine-wool sheep breeds in China: Alpine Merino sheep (AMS), Chinese Merino sheep (CMS), Qinghai fine-wool sheep (QHS), and Aohan fine-wool sheep (AHS). A total of 16 SNPs were detected above the genome-wise significant threshold (P = 5.45E-09), and 79 SNPs were located above the suggestive significance threshold (P = 5.00E-07) from the GWAS results. For YFD and YGFW traits, 7 and 9 SNPs reached the genome-wise significance thresholds, whereas 10 and 12 SNPs reached the suggestive significance threshold, respectively. For YSL and YCFR traits, none of the SNPs reached the genome-wise significance thresholds, whereas 57 SNPs exceeded the suggestive significance threshold. We recorded 14 genes located at the region of ±50-kb near the genome-wise significant SNPs and 59 genes located at the region of ±50-kb near the suggestive significant SNPs. Meanwhile, we used the Average Information Restricted Maximum likelihood algorithm (AI-REML) in the “HIBLUP” package to estimate the heritability and variance components of the four desired yearling wool traits. The estimated heritability values (h2) of YSL, YFD, YGFW, and YCFR were 0.6208, 0.7460, 0.6758, and 0.5559, respectively. We noted that the genetic parameters in this study can be used for fine-wool sheep breeding. The newly detected significant SNPs and the newly identified candidate genes in this study would enhance our understanding of yearling wool formation, and significant SNPs can be applied to genome selection in fine-wool sheep breeding. 相似文献
76.
为明确杂交大豆核心亲本的遗传多样性特点及群体结构特征,以来源中国东北和国外的100份杂交大豆核心亲本为材料,通过SRAP分子标记多态性分析和UPGMA聚类分析等方法进行聚类分析。结果表明:1)SRAP标记共扩增出2 135条条带,其中多态性条带2 130条,多态性位点占比99.76%,每对引物组合扩增出的多态性谱带数为137~204条,平均为178条,引物的多态性信息含量范围在0.074 0~0.153 7,平均值为0.125 7;2)根据遗传相似系数于0.450 0处划分为2个类群,在遗传相似系数0.460 0处将类群Ⅰ划分2个亚群,又在遗传相似系数0.480 0处将类群Ⅱ划分2个亚群,并将主要来源于中国东北的保持系材料划分为类群Ⅰ,主要来源于美国的恢复系材料划分为类群Ⅱ;3)通过对10个已审定强优势杂交种的13个亲本进行分析发现,杂交种亲本间的遗传相似性多分布在0.329 2~0.637 6;4)通过遗传多样性分析发现,类群I与类群Ⅱ内遗传多样性相似,4个亚群中的亚群Ⅰ-1和Ⅱ-2遗传多样性均大于亚群Ⅰ-2和Ⅱ-1;通过主坐标分析,亲本同样被划分为2个类群,验证了聚类分析的结果。综上,基于SRAP分子标记成功将100份春大豆杂交种核心亲本划分为两大类群;其中,类群Ⅰ的中国东北材料与类群Ⅱ的国外材料之间杂交配制组合存在较强的杂种优势。 相似文献
77.
脉孢霉(Neurospora)是食用菌栽培中常见竞争性杂菌,其感染率高而且传播迅速,致使培养基质大量报废、菌袋成品率下降及栽培场所污染。从香菇栽培料中分离鉴定出好食脉孢霉(N.sitophila)菌株,采用药剂平板方法分析6个稀释浓度植物源农药对脉孢霉菌丝的生长抑制效果。结果表明:供试5种农药中,高于500倍稀释浓度药液均可对供试菌株生长产生显著抑制,抑菌率为55%~100%。其中丁子香酚和乙蒜素抑菌率最高,同为100%;印楝素抑菌率最低,为55%。值得一提的是,丁子香酚的1 000倍和2 000倍稀释液平板抑菌率也达100%,乙蒜素同浓度稀释液抑菌率与其相近。以上结果说明:乙蒜素和丁子香酚可作为食用菌脉孢霉绿色防控的优选植物源农药。 相似文献
78.
Xiaobo Guo Jun Chen Jin Yang Qin He Bowen Luo Yafei Lu Tiande Zou Zirui Wang Jinming You 《Journal of animal physiology and animal nutrition》2021,105(6):1063-1074
This study aimed to investigate the protective effects and underlying mechanism of seaweed polysaccharide (SWP) on intestinal epithelial barrier dysfunction induced by E. coli in an IPEC-J2 model. A preliminary study was done to screen optimum SWP concentrations by cell viability, cytotoxicity, apoptosis and proliferation evaluation. The regular study was conducted to evaluate the protective effects of SWP against E. coli challenge via the analysis of transepithelial electrical resistance (TEER), tight junction proteins, NF-κB signalling pathway, proinflammatory cytokines and the E. coli adhesion and invasion. Our results show that 4 h E. coli challenge down-regulated tight junction proteins expression, decreased TEER, activated NF-κB signalling pathway and increased proinflammatory response, which indicates that the E. coli infection model was well-established. Pre-treatment with 240 μg/ml SWP for 24 h alleviated the 4 h E. coli -induced intestinal epithelial barrier dysfunction, as evidenced by the up-regulated expression of Occludin, Claudin-1 and ZO-1 at both mRNA and protein level and the increased TEER of IPEC-J2 cells. Pre-incubation with 240 μg/ml SWP for 24 h inhibited the activation of the NF-κB signalling pathway by 4 h E. coli challenge, including the decreased mRNA expression of TLR-4, MyD88, IκBα, p-65, as well as the reduced ratio of protein expression of p-p65/p65. Also, pre-treatment with 240 μg/ml SWP for 24 h decreased proinflammatory response (IL-6 and TNF-α) induced by 4 h E. coli challenge and decreased the E. coli adhesion and invasion. In conclusion, SWP mitigated intestinal barrier dysfunction caused by E. coli through NF-κB pathway in IPEC-J2 cells and 240 μg/ml SWP exhibited better effect. Our results also provide a fundamental basis for SWP in reducing post-weaning diarrhoea of weaned piglets, especially under E. coli -infected or in-feed antibiotic-free conditions. 相似文献
79.
杨木预水解过程中化学组分的降解行为及P因子调控作用 总被引:1,自引:0,他引:1
预水解具有环境友好性,符合生物炼制的理念。前期关于预水解的研究多集中于半纤维素的降解、分离和利用,而有关预水解过程中木质素降解的系统研究鲜有报道。以杨木为原料,在130~210℃条件下保温30~120 min进行预水解,结合P因子研究得率、葡聚糖、木聚糖、酸不溶木质素和酸溶木质素的降解率,揭示P因子对木质素降解行为的调控作用,探讨各化学组分在预水解过程中的相互作用。研究表明,预水解过程中木质素发生了一定程度的碎片化。随温度升高和时间延长,酸不溶木质素降解率均逐渐升高;当温度为190和210℃时,随时间延长,酸溶木质素降解率先升高后降低。试验证明,P因子对杨木木质素的降解具有调控作用。随着P因子增加,酸不溶木质素降解率呈指数上升,且分为快速降解(P因子<1500)和缓慢降解(P因子>1500)两个阶段;酸溶木质素降解率先上升后下降,在P因子为1926时达到最大值45.9%。此外,预水解过程中碳水化合物和木质素的降解具有相互作用关系。碳水化合物的降解为木质素的溶出打开了物理通道,同时木质素的重新吸附阻碍了其进一步降解。 相似文献
80.