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Citromicrobium bathyomarinum, a novel aerobic bacterium isolated from deep-sea hydrothermal vent plume waters that contains photosynthetic pigment-protein complexes. 下载免费PDF全文
We have taxonomically and phylogenetically characterized a new aerobic bacterial strain (JF-1) that contains photosynthetic pigment-protein complexes and which was recently isolated from black smoker plume waters of the Juan de Fuca Ridge. Strain JF-1 is a gram-negative, yellow-pigmented, motile bacterium that is salt-, pH-, and thermotolerant. These properties are consistent with an oligotrophic adaptation to varied environmental conditions thought to exist around deep-sea hydrothermal vents. The analysis of 16S rDNA sequences revealed that strain JF-1 forms a separate phylogenetic branch between the genus Erythromonas and the Erythromicrobium-Porphyrobacter-Erythrobacter cluster within the alpha subclass of the Proteobacteria. The taxonomic name Citromicrobium bathyomarinum (gen. nov., sp. nov.) is proposed for strain JF-1. 相似文献
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Emily Olfson Catherine E. Cottrell Nicholas O. Davidson Christina A. Gurnett Jonathan W. Heusel Nathan O. Stitziel Li-Shiun Chen Sarah Hartz Rakesh Nagarajan Nancy L. Saccone Laura J. Bierut 《PloS one》2015,10(9)
The American College of Medical Genetics and Genomics (ACMG) recommends that clinical sequencing laboratories return secondary findings in 56 genes associated with medically actionable conditions. Our goal was to apply a systematic, stringent approach consistent with clinical standards to estimate the prevalence of pathogenic variants associated with such conditions using a diverse sequencing reference sample. Candidate variants in the 56 ACMG genes were selected from Phase 1 of the 1000 Genomes dataset, which contains sequencing information on 1,092 unrelated individuals from across the world. These variants were filtered using the Human Gene Mutation Database (HGMD) Professional version and defined parameters, appraised through literature review, and examined by a clinical laboratory specialist and expert physician. Over 70,000 genetic variants were extracted from the 56 genes, and filtering identified 237 variants annotated as disease causing by HGMD Professional. Literature review and expert evaluation determined that 7 of these variants were pathogenic or likely pathogenic. Furthermore, 5 additional truncating variants not listed as disease causing in HGMD Professional were identified as likely pathogenic. These 12 secondary findings are associated with diseases that could inform medical follow-up, including cancer predisposition syndromes, cardiac conditions, and familial hypercholesterolemia. The majority of the identified medically actionable findings were in individuals from the European (5/379) and Americas (4/181) ancestry groups, with fewer findings in Asian (2/286) and African (1/246) ancestry groups. Our results suggest that medically relevant secondary findings can be identified in approximately 1% (12/1092) of individuals in a diverse reference sample. As clinical sequencing laboratories continue to implement the ACMG recommendations, our results highlight that at least a small number of potentially important secondary findings can be selected for return. Our results also confirm that understudied populations will not reap proportionate benefits of genomic medicine, highlighting the need for continued research efforts on genetic diseases in these populations. 相似文献
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Breakage of the T cell receptor α chain locus in non malignant clones from patients with ataxia telangiectasia 总被引:3,自引:0,他引:3
A. Heppell S. V. Butterworth R. J. Hollis A. A. Kennaugh D. W. Beatty A. M. R. Taylor 《Human genetics》1988,79(4):360-364
Summary Patients with ataxia telangiectasia (A-T) develop specific chromosome translocations, which may confer a proliferative advantage, resulting in the appearance of large clones in the peripheral blood lymphocytes. These lymphocytes are not malignant. Using in situ hybridisation techniques we have investigated a consistent 14q11 translocation break-point observed in a t(X;14)(q28;q11) translocation clone from each of two different patients and a t(14;14)(q11;q32) clone from a third patient. In all cases the chromosome translocation involved breakage within the chain locus of the T cell receptor (TCR), between the variable and constant regions, at 14q11. Chromosome rearrangement involving breakage within TCR can therefore precede the development of malignancy. Further chromosomal rearrangement may be required in these patients, for progression to the leukaemic state. 相似文献
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Beatty J 《Journal of the history of biology》1988,21(2):245-263
Conclusion: Scientists qua engineers Of all the scientists discussed by Mitman, Keller, and Taylor, Odum stands out most as the technocrat, the social engineer. But less obvious candidates, like Allee, also fancied themselves in this capacity: Our task as biologists and as citizens of a civilized country, is a practical engineering job. Allee had in mind the establishment of an international cooperative order based on his biological principles. He apparently did not recognize the extent to which his principles were themselves an engineering feat: he had already constructed a world in which eternal peace and order were possible.To an engineer in the traditional sense, the world is changeable, but not in all respects; there are constraints, and these constraints are taken very seriously. Scientists acting as engineers, in the traditional sense, must also pay attention to constraints. But scientists sometimes also take the option of engineering the very constraints, intellectually reconstructing the world so that it can (supposedly) be physically manipulated in the desired direction. There seems to be a lot of engineering, in the extended sense, going on in the very interesting stories that Mitman, Keller, and Taylor tell. 相似文献
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Adhesion-mediating molecules of human monocytes 总被引:1,自引:0,他引:1
Adhesion of monocytes to each other and to T cells and substrates is increased by phorbol esters. In the presence of these compounds monocyte aggregation was almost completely inhibited (greater than 90%) by monoclonal antibody 60.3. This antibody recognizes GP90 (CD18), a leukocyte surface glycoprotein which is separately and noncovalently associated to either GP160 (CD11a), GP155 (CD11b), or GP130 (CD11c). Anti-LFA-1 antibody (CD11a) was only partially inhibitory (35%) while antibodies 60.1 (CD11b) and anti-Leu-M5 (CD11c) had a minimal inhibitory effect (10%). Antibody LB-2 recognizing a single glycoprotein distinct from the GP90-GP160 complex and expressed on activated B and T cells, monocytes, and vascular endothelial cells was partially inhibitory (22%). Monoclonal antibodies anti-C3bR (CD35), T29/33 (CD45, leukocyte common antigen 200). TA-1 (CD11a), OKM1 (CD11b), F10-44-2 (brain-leukocyte antigen), OKM5 (monocyte-endothelial cell antigen) and to class I or class II molecules exerted no inhibition on the monocyte aggregation. Fab fragments of antibody 60.3 efficiently inhibited not only monocyte aggregation in the absence or presence of phorbol esters but also adhesion of these cells to autologous or allogeneic T lymphocytes and, to a lesser extent, to plastic surfaces. It is thus concluded that GP90, either alone or associated to the larger glycoproteins, and LB-2 antigen mediate monocyte adhesion. 相似文献
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