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排序方式: 共有166条查询结果,搜索用时 31 毫秒
91.
Auwerx J Avner P Baldock R Ballabio A Balling R Barbacid M Berns A Bradley A Brown S Carmeliet P Chambon P Cox R Davidson D Davies K Duboule D Forejt J Granucci F Hastie N de Angelis MH Jackson I Kioussis D Kollias G Lathrop M Lendahl U Malumbres M von Melchner H Müller W Partanen J Ricciardi-Castagnoli P Rigby P Rosen B Rosenthal N Skarnes B Stewart AF Thornton J Tocchini-Valentini G Wagner E Wahli W Wurst W 《Nature genetics》2004,36(9):925-927
The European Mouse Mutagenesis Consortium is the European initiative contributing to the international effort on functional annotation of the mouse genome. Its objectives are to establish and integrate mutagenesis platforms, gene expression resources, phenotyping units, storage and distribution centers and bioinformatics resources. The combined efforts will accelerate our understanding of gene function and of human health and disease. 相似文献
92.
Methane oxidation by an extremely acidophilic bacterium of the phylum Verrucomicrobia 总被引:4,自引:0,他引:4
Dunfield PF Yuryev A Senin P Smirnova AV Stott MB Hou S Ly B Saw JH Zhou Z Ren Y Wang J Mountain BW Crowe MA Weatherby TM Bodelier PL Liesack W Feng L Wang L Alam M 《Nature》2007,450(7171):879-882
Aerobic methanotrophic bacteria consume methane as it diffuses away from methanogenic zones of soil and sediment. They act as a biofilter to reduce methane emissions to the atmosphere, and they are therefore targets in strategies to combat global climate change. No cultured methanotroph grows optimally below pH 5, but some environments with active methane cycles are very acidic. Here we describe an extremely acidophilic methanotroph that grows optimally at pH 2.0-2.5. Unlike the known methanotrophs, it does not belong to the phylum Proteobacteria but rather to the Verrucomicrobia, a widespread and diverse bacterial phylum that primarily comprises uncultivated species with unknown genotypes. Analysis of its draft genome detected genes encoding particulate methane monooxygenase that were homologous to genes found in methanotrophic proteobacteria. However, known genetic modules for methanol and formaldehyde oxidation were incomplete or missing, suggesting that the bacterium uses some novel methylotrophic pathways. Phylogenetic analysis of its three pmoA genes (encoding a subunit of particulate methane monooxygenase) placed them into a distinct cluster from proteobacterial homologues. This indicates an ancient divergence of Verrucomicrobia and Proteobacteria methanotrophs rather than a recent horizontal gene transfer of methanotrophic ability. The findings show that methanotrophy in the Bacteria is more taxonomically, ecologically and genetically diverse than previously thought, and that previous studies have failed to assess the full diversity of methanotrophs in acidic environments. 相似文献
93.
94.
95.
MicroRNAs can generate thresholds in target gene expression 总被引:2,自引:0,他引:2
Mukherji S Ebert MS Zheng GX Tsang JS Sharp PA van Oudenaarden A 《Nature genetics》2011,43(9):854-859
MicroRNAs (miRNAs) are short, highly conserved noncoding RNA molecules that repress gene expression in a sequence-dependent manner. We performed single-cell measurements using quantitative fluorescence microscopy and flow cytometry to monitor a target gene's protein expression in the presence and absence of regulation by miRNA. We find that although the average level of repression is modest, in agreement with previous population-based measurements, the repression among individual cells varies dramatically. In particular, we show that regulation by miRNAs establishes a threshold level of target mRNA below which protein production is highly repressed. Near this threshold, protein expression responds sensitively to target mRNA input, consistent with a mathematical model of molecular titration. These results show that miRNAs can act both as a switch and as a fine-tuner of gene expression. 相似文献
96.
Suhre K Wallaschofski H Raffler J Friedrich N Haring R Michael K Wasner C Krebs A Kronenberg F Chang D Meisinger C Wichmann HE Hoffmann W Völzke H Völker U Teumer A Biffar R Kocher T Felix SB Illig T Kroemer HK Gieger C Römisch-Margl W Nauck M 《Nature genetics》2011,43(6):565-569
We present a genome-wide association study of metabolic traits in human urine, designed to investigate the detoxification capacity of the human body. Using NMR spectroscopy, we tested for associations between 59 metabolites in urine from 862 male participants in the population-based SHIP study. We replicated the results using 1,039 additional samples of the same study, including a 5-year follow-up, and 992 samples from the independent KORA study. We report five loci with joint P values of association from 3.2 × 10(-19) to 2.1 × 10(-182). Variants at three of these loci have previously been linked with important clinical outcomes: SLC7A9 is a risk locus for chronic kidney disease, NAT2 for coronary artery disease and genotype-dependent response to drug toxicity, and SLC6A20 for iminoglycinuria. Moreover, we identify rs37369 in AGXT2 as the genetic basis of hyper-β-aminoisobutyric aciduria. 相似文献
97.
Higgins GC Devenish RJ Beart PM Nagley P 《Cellular and molecular life sciences : CMLS》2011,68(22):3725-3740
Primary neurons undergo insult-dependent programmed cell death. We examined autophagy as a process contributing to cell death
in cortical neurons after treatment with either hydrogen peroxide (H2O2) or staurosporine. Although caspase-9 activation and cleavage of procaspase-3 were significant following staurosporine treatment,
neither was observed following H2O2 treatment, indicating a non-apoptotic death. Autophagic activity increased rapidly with H2O2, but slowly with staurosporine, as quantified by processing of endogenous LC3. Autophagic induction by both stressors increased
the abundance of fluorescent puncta formed by GFP-LC3, which could be blocked by 3-methyladenine. Significantly, such inhibition
of autophagy blocked cell death induced by H2O2 but not staurosporine. Suppression of Atg7 inhibited cell death by H2O2, but not staurosporine, whereas suppression of Beclin 1 prevented cell death by both treatments, suggesting it has a complex
role regulating both apoptosis and autophagy. We conclude that autophagic mechanisms are activated in an insult-dependent
manner and that H2O2 induces autophagic cell death. 相似文献
98.
Smith UM Consugar M Tee LJ McKee BM Maina EN Whelan S Morgan NV Goranson E Gissen P Lilliquist S Aligianis IA Ward CJ Pasha S Punyashthiti R Malik Sharif S Batman PA Bennett CP Woods CG McKeown C Bucourt M Miller CA Cox P Algazali L Trembath RC Torres VE Attie-Bitach T Kelly DA Maher ER Gattone VH Harris PC Johnson CA 《Nature genetics》2006,38(2):191-196
Meckel-Gruber syndrome is a severe autosomal, recessively inherited disorder characterized by bilateral renal cystic dysplasia, developmental defects of the central nervous system (most commonly occipital encephalocele), hepatic ductal dysplasia and cysts and polydactyly. MKS is genetically heterogeneous, with three loci mapped: MKS1, 17q21-24 (ref. 4); MKS2, 11q13 (ref. 5) and MKS3 (ref. 6). We have refined MKS3 mapping to a 12.67-Mb interval (8q21.13-q22.1) that is syntenic to the Wpk locus in rat, which is a model with polycystic kidney disease, agenesis of the corpus callosum and hydrocephalus. Positional cloning of the Wpk gene suggested a MKS3 candidate gene, TMEM67, for which we identified pathogenic mutations for five MKS3-linked consanguineous families. MKS3 is a previously uncharacterized, evolutionarily conserved gene that is expressed at moderate levels in fetal brain, liver and kidney but has widespread, low levels of expression. It encodes a 995-amino acid seven-transmembrane receptor protein of unknown function that we have called meckelin. 相似文献
99.
Perry GH Dominy NJ Claw KG Lee AS Fiegler H Redon R Werner J Villanea FA Mountain JL Misra R Carter NP Lee C Stone AC 《Nature genetics》2007,39(10):1256-1260
Starch consumption is a prominent characteristic of agricultural societies and hunter-gatherers in arid environments. In contrast, rainforest and circum-arctic hunter-gatherers and some pastoralists consume much less starch. This behavioral variation raises the possibility that different selective pressures have acted on amylase, the enzyme responsible for starch hydrolysis. We found that copy number of the salivary amylase gene (AMY1) is correlated positively with salivary amylase protein level and that individuals from populations with high-starch diets have, on average, more AMY1 copies than those with traditionally low-starch diets. Comparisons with other loci in a subset of these populations suggest that the extent of AMY1 copy number differentiation is highly unusual. This example of positive selection on a copy number-variable gene is, to our knowledge, one of the first discovered in the human genome. Higher AMY1 copy numbers and protein levels probably improve the digestion of starchy foods and may buffer against the fitness-reducing effects of intestinal disease. 相似文献
100.
Kassmann CM Lappe-Siefke C Baes M Brügger B Mildner A Werner HB Natt O Michaelis T Prinz M Frahm J Nave KA 《Nature genetics》2007,39(8):969-976
Oligodendrocytes myelinate axons for rapid impulse conduction and contribute to normal axonal functions in the central nervous system. In multiple sclerosis, demyelination is caused by autoimmune attacks, but the role of oligodendroglial cells in disease progression and axon degeneration is unclear. Here we show that oligodendrocytes harbor peroxisomes whose function is essential for maintaining white matter tracts throughout adult life. By selectively inactivating the import factor PEX5 in myelinating glia, we generated mutant mice that developed normally, but within several months showed ataxia, tremor and premature death. Absence of functional peroxisomes from oligodendrocytes caused widespread axonal degeneration and progressive subcortical demyelination, but did not interfere with glial survival. Moreover, it caused a strong proinflammatory milieu and, unexpectedly, the infiltration of B and activated CD8+ T cells into brain lesions. We conclude that peroxisomes provide oligodendrocytes with an essential neuroprotective function against axon degeneration and neuroinflammation, which is relevant for human demyelinating diseases. 相似文献