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991.
rmlB and rmlC genes are essential for growth of mycobacteria 总被引:4,自引:0,他引:4
992.
Fontán-Lozano A López-Lluch G Delgado-García JM Navas P Carrión AM 《Molecular neurobiology》2008,38(2):167-177
Aging is associated with the decline of cognitive properties. This situation is magnified when neurodegenerative processes
associated with aging appear in human patients. Neuronal synaptic plasticity events underlie cognitive properties in the central
nervous system. Caloric restriction (CR; either a decrease in food intake or an intermittent fasting diet) can extend life
span and increase disease resistance. Recent studies have shown that CR can have profound effects on brain function and vulnerability
to injury and disease. Moreover, CR can stimulate the production of new neurons from stem cells (neurogenesis) and can enhance
synaptic plasticity, which modulate pain sensation, enhance cognitive function, and may increase the ability of the brain
to resist aging. The beneficial effects of CR appear to be the result of a cellular stress response stimulating the production
of proteins that enhance neuronal plasticity and resistance to oxidative and metabolic insults; they include neurotrophic
factors, neurotransmitter receptors, protein chaperones, and mitochondrial biosynthesis regulators. In this review, we will
present and discuss the effect of CR in synaptic processes underlying analgesia and cognitive improvement in healthy, sick,
and aging animals. We will also discuss the possible role of mitochondrial biogenesis induced by CR in regulation of neuronal
synaptic plasticity. 相似文献
993.
Molecular identification and dynamics of microbial communities in reactor treating organic household waste 总被引:1,自引:0,他引:1
Juliana Cardinali-Rezende Renan B. Debarry Luis F. D. B. Colturato Eduardo V. Carneiro Edmar Chartone-Souza Andrea M. A. Nascimento 《Applied microbiology and biotechnology》2009,84(4):777-789
The prokaryotic diversity associated with organic household waste (OHW), leachate (start-up inoculum), and mesophilic anaerobic
digestion processes in the degradation of OHW for 44 and 90 days was investigated using a culture-independent approach. Bacterial
and archaeal 16S rRNA and mcrA gene clone libraries were constructed from community DNA preparations. Bacterial clones were affiliated with 13 phyla, of
which Firmicutes, Proteobacteria, and Bacteroidetes were represented in all libraries, whereas Actinobacteria, Thermotogae, Lentisphaerae, Acidobacteria, Chloroflexi, Cyanobacteria, Synergistetes, Spirochaetes, Deferribacteres, and Deinococcus-Thermus were exclusively identified in a single library. Within the Archaea domain, the Euryarchaeota phylum was the only one represented. Corresponding sequences were associated with the following orders of hydrogenotrophic
methanogens: Methanomicrobiales (Methanoculleus genus) and Methanobacteriales (Methanosphaera and Methanobacterium genera). One archaeal clone was not affiliated with any order and may represent a novel taxon. Diversity indices showed greater
diversity of Bacteria when compared to methanogenic Archaea. 相似文献
994.
利用全基因组连锁不平衡估计中国荷斯坦牛有效群体大小 总被引:2,自引:0,他引:2
有效群体大小是群体遗传学研究的一个重要内容,有助于我们更清楚地了解群体的遗传变异、进化和复杂性状的遗传机制等。随着高密度SNP标记的出现,越来越多的研究利用SNP标记间连锁不平衡估计有效群体大小。文章采集北京地区中国荷斯坦牛2 093个样本,并利用牛SNP芯片(Illumina BovineSNP50,含5 4001 SNPs)进行基因型测定,估计不同世代中国荷斯坦牛的有效群体大小。质量控制标准设定为SNP检出率0.95,最小等位基因频率>0.05,样本检出率0.95,哈代温伯格平衡检验显著性水平P<0.0001。经过质量控制,共1 968个样本和38 796个SNPs用于连锁不平衡分析。文章选取SNP间距0.1、0.2、0.5、1、2、5、10、15(Mb),估计中国荷斯坦牛在4世代之前有效群体大小。结果表明,中国荷斯坦牛的有效群体呈逐代下降趋势,至4世代前,中国荷斯坦牛平均有效群体为45头左右。 相似文献
995.
Analysis of trehalose-6-phosphate synthase (TPS) gene family suggests the formation of TPS complexes in rice 总被引:2,自引:0,他引:2
Trehalose-6-phosphate (T6P), an intermediate in the trehalose biosynthesis pathway, is emerging as an important regulator
of plant metabolism and development. T6P levels are potentially modulated by a group of trehalose-6-phosphate synthase (TPS)
and trehalose-6-phosphate phosphatase (TPP) homologues. In this study, we have isolated 11 TPS genes encoding proteins with both TPS and TPP domains, from rice. Functional complement assays performed in yeast tps1 and tps2 mutants, revealed that only OsTPS1 encodes an active TPS enzyme and no OsTPS protein possesses TPP activity. By using a yeast two-hybrid analysis, a complicated
interaction network occurred among OsTPS proteins, and the TPS domain might be essential for this interaction to occur. The
interaction between OsTPS1 and OsTPS8 in vivo was confirmed by bimolecular fluorescence complementation and coimmunoprecipitation
assays. Furthermore, our gel filtration assay showed that there may exist two forms of OsTPS1 (OsTPS1a and OsTPS1b) with different
elution profiles in rice. OsTPS1b was particularly cofractionated with OsTPS5 and OsTPS8 in the 360 kDa complex, while OsTPS1a
was predominantly incorporated into the complexes larger than 360 kDa. Collectively, these results suggest that OsTPS family members may form trehalose-6-phosphate synthase complexes and therefore potentially modify T6P levels to regulate
plant development. 相似文献
996.
Eduard Akhunov Charles Nicolet Jan Dvorak 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,119(3):507-517
Single nucleotide polymorphisms (SNPs) are indispensable in such applications as association mapping and construction of high-density
genetic maps. These applications usually require genotyping of thousands of SNPs in a large number of individuals. Although
a number of SNP genotyping assays are available, most of them are designed for SNP genotyping in diploid individuals. Here,
we demonstrate that the Illumina GoldenGate assay could be used for SNP genotyping of homozygous tetraploid and hexaploid
wheat lines. Genotyping reactions could be carried out directly on genomic DNA without the necessity of preliminary PCR amplification.
A total of 53 tetraploid and 38 hexaploid homozygous wheat lines were genotyped at 96 SNP loci. The genotyping error rate
estimated after removal of low-quality data was 0 and 1% for tetraploid and hexaploid wheat, respectively. Developed SNP genotyping
assays were shown to be useful for genotyping wheat cultivars. This study demonstrated that the GoldenGate assay is a very
efficient tool for high-throughput genotyping of polyploid wheat, opening new possibilities for the analysis of genetic variation
in wheat and dissection of genetic basis of complex traits using association mapping approach.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
997.
Miyamoto K Okunishi M Nukui E Tsuchiya T Kobayashi T Imada C Tsujibo H 《Archives of microbiology》2007,188(6):619-628
998.
Pectinase was immobilized on a sodium alginate support using glutaraldehyde and retained 66% activity. The optimal pH for
activity shifted from 3.0 to 3.5 after immobilization; however, the optimum temperature remained unchanged at 40°C. The immobilized
enzyme also had a higher thermal stability and reusability than the free enzyme, and retained 80% of initial activity after
11 batch reactions. 相似文献
999.
植物D型细胞周期蛋白 总被引:1,自引:0,他引:1
D型细胞周期蛋白(cyclinD,CycD)调控着细胞周期G1/S的转换,基本过程为CycD在外界环境刺激下积累,并与周期蛋白依赖激酶(cyclin-dependentkinase,CDK)形成有活性的激酶,促进成视网膜细胞瘤蛋白(retinoblastoma,Rb)磷酸化,使E2F因子释放,由此促使G1/S转换,这一调控系统在高等真核生物中具有很高的保守性。CycD与其他细胞周期蛋白表达有所不同,其受到生长因子的强烈诱导,去掉生长因子后,表达水平迅速下降,导致细胞被抑制在G1期。大量研究表明,CycD是细胞周期中一个关键的“感受因子”,CycD基因的表达是细胞周期进程中的限速因子,影响着植物的生长发育。现对植物CycD的特征以及在细胞周期中的功能进行综述,并探讨了其在植物生长发育中的作用。 相似文献
1000.
Ogawa S Tokumoto Y Miyake J Nagamune T 《In vitro cellular & developmental biology. Animal》2011,47(7):464-469
Induced pluripotent stem cells (iPSCs) prepared from somatic cells might become a novel therapeutic tool in regenerative medicine,
especially for the central nervous system (CNS). In this study, we attempted to induce O4-positive (O4+) oligodendrocytes from adult human fibroblast-derived iPSCs in vitro. We used two adult human iPSC cell lines, 201B7 and
253G1. 201B7 was induced by four-gene transduction (oct4, sox2, klf4, c-myc), and 253G1 was induced by three-gene transduction
(oct4, sox2, klf4). We treated these cells with two in vitro oligodendrocyte-directed differentiation protocols that were
optimized for human embryonic stem cells. One protocol used platelet-derived growth factor as the major mitogen for oligodendrocyte
lineage cells, and the other protocol used epidermal growth factor (EGF) as the mitogen. Although the differentiation efficiency
was low (less than 0.01%), we could induce O4+ oligodendrocytes from 253G1 cells using the EGF-dependent differentiation protocol. This is the first report of the in vitro
induction of oligodendrocytes differentiation from human iPSCs. 相似文献