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Henipaviruses and lyssaviruses target nucleolar treacle protein and regulate ribosomal RNA synthesis
Stephen M. Rawlinson Tianyue Zhao Katie Ardipradja Yilin Zhang Patrick F. Veugelers Jennifer A. Harper Cassandra T. David Vinod Sundaramoorthy Gregory W. Moseley 《Traffic (Copenhagen, Denmark)》2023,24(3):146-157
The nucleolus is a common target of viruses and viral proteins, but for many viruses the functional outcomes and significance of this targeting remains unresolved. Recently, the first intranucleolar function of a protein of a cytoplasmically-replicating negative-sense RNA virus (NSV) was identified, with the finding that the matrix (M) protein of Hendra virus (HeV) (genus Henipavirus, family Paramyxoviridae) interacts with Treacle protein within nucleolar subcompartments and mimics a cellular mechanism of the nucleolar DNA-damage response (DDR) to suppress ribosomal RNA (rRNA) synthesis. Whether other viruses utilise this mechanism has not been examined. We report that sub-nucleolar Treacle targeting and modulation is conserved between M proteins of multiple Henipaviruses, including Nipah virus and other potentially zoonotic viruses. Furthermore, this function is also evident for P3 protein of rabies virus, the prototype virus of a different RNA virus family (Rhabdoviridae), with Treacle depletion in cells also found to impact virus production. These data indicate that unrelated proteins of viruses from different families have independently developed nucleolar/Treacle targeting function, but that modulation of Treacle has distinct effects on infection. Thus, subversion of Treacle may be an important process in infection by diverse NSVs, and so could provide novel targets for antiviral approaches with broad specificity. 相似文献
54.
David J. Eide Jamie T. Bridgham Zhong Zhao James R. Mattoon 《Molecular genetics and genomics : MGG》1993,241(3-4):447-456
Mutations in the GEF2 gene of the yeast Saccharomyces cerevisiae have pleiotropic effects. The gef2 mutants display a petite phenotype. These cells grow slowly on several different carbon sources utilized exclusively or primarily by respiration. This phenotype is suppressed by adding large amounts of iron to the growth medium. A defect in mitochondrial function may be the cause of the petite phenotype: the rate of oxygen consumption by intact gef2 cells and by mitochondrial fractions isolated from gef2 mutants was reduced 60%–75% relative to wild type. Cytochrome levels were unaffected in gef2 mutants, indicating that heme accumulation is not significantly altered in these strains. The gef2 mutants were also more sensitive than wild type to growth inhibition by several divalent cations including Cu. We found that the cup5 mutation, causing Cu sensitivity, is allelic to gef2 mutations. The GEF2 gene was isolated, sequenced, and found to be identical to VMA3, the gene encoding the vacuolar H +-ATPase proteolipid subunit. These genetic and biochemical analyses demonstrate that the vacuolar H +-ATPase plays a previously unknown role in Cu detoxification, mitochondrial function, and iron metabolism. 相似文献
55.
黑龙江宁安盆地穆棱组及其孢粉型组合新发现 总被引:8,自引:2,他引:6
黑龙江宁安盆地是一个具有油气勘探远景的中小型盆地,主要目的层为下白垩统。新发现了一套相当于邻区穆棱组的地层,孢粉化石十分丰富,建立了5个孢粉组合带,通过对两口石油探井生物地层的研究,建立了该舅地新的地层层序,并对穆棱组的时代和沉积环境进行了讨论。 相似文献
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Summary Xanthan fermentations in W/O dispersions performed better than the control in both small flasks and a 6.6-L fermentor. The better bulk mixing and oxygen transfer achieved in the dispersion resulted in a still rising xanthan concentration of 65 g/L, compared with 26 g/L in the control. A phase inversion phenomenon was observed when n-hexadecane recovered from previous runs was used as the oil. 相似文献
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Apurinic/apyrimidinic endonuclease 1 (APE1) is a multifunctional DNA repair protein localized in different subcellular compartments. The mechanisms responsible for the highly regulated subcellular localization and “interactomes” of this protein are not fully understood but have been closely correlated to the posttranslational modifications in different biological context. In this work, we attempted to develop a bio-nanocomposite with antibody-like properties that could capture APE1 from cellular matrices to enable the comprehensive study of this protein. By fixing the template APE1 on the avidin-modified surface of silica-coated magnetic nanoparticles, we first added 3-aminophenylboronic acid to react with the glycosyl residues of avidin, followed by addition of 2-acrylamido-2-methylpropane sulfonic acid as the second functional monomer to perform the first step imprinting reaction. To further enhance the affinity and selectivity of the binding sites, we carried out the second step imprinting reaction with dopamine as the functional monomer. After the polymerization, we modified the nonimprinted sites with methoxypoly (ethylene glycol) amine (mPEG-NH2). The resulting molecularly imprinted polymer-based bio-nanocomposite showed high affinity, specificity, and capacity for template APE1. It allowed for the extraction of APE1 from the cell lysates with high recovery and purity. Moreover, the bound protein could be effectively released from the bio-nanocomposite with high activity. The bio-nanocomposite offers a very useful tool for the separation of APE1 from various complex biological samples. 相似文献
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杨树拟茎点菌溃疡病的研究 总被引:1,自引:0,他引:1
本病系我国杨树新发生的一种病害。病原菌的分生孢子有2种形状,无色透明、单胞,呈纺缍形孢子大小为1.64—2.74×9.59—13.7μm。线形孢子顶端弯钩状大小为1.37—1.78×15—27.4μm。病原菌适宜生长的培养基为PDA、麦芽粉、豆饼粉培养基;温度为25—32℃和pH6—10。本病于4月下旬发病,5月中下旬分生孢子成熟,6月中下旬为分生孢子飞散高峰期。经室内采用多菌灵、甲基托布津、福美砷的200倍液浸泡插穗30、60、90分钟处理均有药害,采用100—200倍液浸泡10分钟无药害,对病害有防效。造林地幼树可采用上述药剂的100倍液进行刮破病斑涂抹,防效可达87.5%。 相似文献
60.
Hejun Liu Xiaoyu Zhao Gui Xue Chuansheng Chen Qi Dong Xuping Gao Li Yang Chunhui Chen 《Genes, Brain & Behavior》2023,22(1):e12835
Genetic studies on attention have mainly focused on children with attention-deficit/hyperactivity disorder (ADHD), so little systematic research has been conducted on genetic correlates of attention performance and their potential brain mechanisms among healthy individuals. The current study included a genome-wide association study (GWAS, N = 1145 healthy young adults) aimed to identify genes associated with sustained attention and an imaging genetics study (an independent sample of 483 healthy young adults) to examine any identified genes' influences on brain function. The GWAS found that TTLL11 showed genome-wide significant associations with sustained attention, with rs13298112 as the most significant SNP and the GG homozygotes showing more impulsive but also more focused responses than the A allele carriers. A retrospective examination of previously published ADHD GWAS results confirmed an un-reported, small but statistically significant effect of TTLL11 on ADHD. The imaging genetics study replicated this association and showed that the TTLL11 gene was associated with resting state activity and connectivity of the somatomoter network, and can be predicted by dorsal attention network connectivity. Specifically, the GG homozygotes showed lower brain activity, weaker brain network connectivity, and non-significant brain-attention association compared to the A allele carriers. Expression database showed that expression of this gene is enriched in the brain and that the G allele is associated with lower expression level than the A allele. These results suggest that TTLL11 may play a major role in healthy individuals' attention performance and may also contribute to the etiology of ADHD. 相似文献