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81.
25 neuronal tumours with a panel of antibodies were studied and it was found that vimentin was present in 15 tumours. It was also found in a few cells within rosettes. PGP 9.5 showed a somatic pattern of staining with nuclear and perinuclear positivity in 23. Neurofilament reactivity was found in 14. Retinal S-antigen was detected only in one medulloblastoma, 3/4 pineal tumours and 2/2 retinoblastomas. Reactivity, for synaptophysin was present in 2/5 medulloblastomas, 3/10 neuroblastomas and 2/2 retinoblastomas. GFAP was demonstrated in scattered tumour cells in 4/5 medulloblastomas. Two of these were the only tumours featuring bipolar differentiation whilst it was unipolar in the remainder. The significance of these findings in relation to the ontogeny of these tumours is discussed.  相似文献   
82.
PARP inhibition can induce anti-neoplastic effects when used as monotherapy or in combination with chemo- or radiotherapy in various tumor settings; however, the basis for the anti-metastasic activities resulting from PARP inhibition remains unknown. PARP inhibitors may also act as modulators of tumor angiogenesis. Proteomic analysis of endothelial cells revealed that vimentin, an intermediary filament involved in angiogenesis and a specific hallmark of EndoMT (endothelial to mesenchymal transition) transformation, was down-regulated following loss of PARP-1 function in endothelial cells. VE-cadherin, an endothelial marker of vascular normalization, was up-regulated in HUVEC treated with PARP inhibitors or following PARP-1 silencing; vimentin over-expression was sufficient to drive to an EndoMT phenotype. In melanoma cells, PARP inhibition reduced pro-metastatic markers, including vasculogenic mimicry. We also demonstrated that vimentin expression was sufficient to induce increased mesenchymal/pro-metastasic phenotypic changes in melanoma cells, including ILK/GSK3-β-dependent E-cadherin down-regulation, Snail1 activation and increased cell motility and migration. In a murine model of metastatic melanoma, PARP inhibition counteracted the ability of melanoma cells to metastasize to the lung. These results suggest that inhibition of PARP interferes with key metastasis-promoting processes, leading to suppression of invasion and colonization of distal organs by aggressive metastatic cells.  相似文献   
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This article addresses the semiotic problem of how meaning is agentially grounded: how actual meaning is possible and is justifiably supported by agents’ capabilities and purposes. This article is particularly focused on human agential grounding; however, to a great degree, insights presented here can be extended to other living beings. Specifically, agential meaning is examined here inside the framework of agentive semiotics and embodied, situated and enactive cognition theories, in line with the mind-life continuity general thesis (which intends to naturalize mind and experience). To offer clarity and methodological precision about agential grounding, three explanation categories (called recurrences) are proposed: phylogenetic recurrence, the evolutionary basis for corporal/embodied grounding; ontogenetic recurrence, the developmental basis for individual meaning grounding; and collective recurrence, the basis for meaning recognized, attributed and assigned inside social contexts. These recurrences are conceived as three types of general processes that constantly enclose possibilities for purpose and meaning emergence in humans. As a result of these types of recurrences, two categories of human agendas or purposes are also proposed: individual and collective. Finally, remarks about how these categories can be useful for semiotic analysis and further research are suggested.  相似文献   
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Plasmid genes or regions that are conditionally lethal to Escherichia coli have been called kil and those lethal to Klebsiella but not to E. coli have been called kik. Both classes of genes are found in or close to the N pilus region of the plasmid pCU1 and the closely related plasmid pKM101. Here we describe two new and overlapping lethal genes that are located between kikA and traA of the plasmid pCU1 and display host specificity. KilC is lethal in E. coli and Klebsiella while kikC is lethal only in Klebsiella. The previously identified korA gene is sufficient to override the lethality of kilC in trans or in cis but is insufficient to override kikC. kilC expression in E. coli leads to cell death accompanied by an increase in average cell length without affecting septum formation.  相似文献   
87.
Gadolinium-containing carbon nanomaterials are a new class of contrast agent for magnetic resonance imaging. They are characterized by a superior proton relaxivity to any current commercial gadolinium contrast agent and offer the possibility to design multifunctional contrasts. Intense efforts have been made to develop these nanomaterials because of their potential for better results than the available gadolinium contrast agents. The aim of the present work is to provide a review of the advances in research on gadolinium-containing carbon nanomaterials and their advantages over conventional gadolinium contrast agents. Due to their enhanced proton relaxivity, they can provide a reliable imaging contrast for cells, tissues or organs with much smaller doses than currently used in clinical practice, thus leading to reduced toxicity (as shown by cytotoxicity and biodistribution studies). Their active targeting capability allows for improved MRI of molecular or cellular targets, overcoming the limited labelling capability of available contrast agents (restricted to physiological irregularities during pathological conditions). Their potential of multifunctionality encompasses multimodal imaging and the combination of imaging and therapy.  相似文献   
88.
Microorganisms strongly influence and are required to generate the selective substrate that provides nutrients and support for fungal growth, and ultimately to induce mushroom fructification under controlled environmental conditions. In this work, the fungal and bacterial microbiota living in the different substrates employed in a commercial crop (compost phase I, II and III, flush 1 and 2, and casing material on day 1, 6 and 8 after compost casing and during flush 1 and 2) have been characterized along the different stages of cultivation by metataxonomic analysis (16S rRNA and ITS2), analysis of phospholipid fatty acid content (PLFAs) and RT-qPCR. Additionally, laccase activity and the content of lignin and complex carbohydrates in compost and casing have been quantified. The bacterial diversity in compost and casing increased throughout the crop cycle boosted by the connection of both substrates. As reflected by the PLFAs, the total living bacterial biomass appears to be negatively correlated with the mycelium of the crop. Agaricus bisporus was the dominant fungal species in colonized substrates, displacing the pre-eminent Ascomycota, accompanied by a sustained increase in laccase activity, which is considered to be a major product of protein synthesis during the mycelial growth of champignon. From phase II onwards, the metabolic machinery of the fungal crop degrades lignin and carbohydrates in compost, while these components are hardly degraded in casing, which reflects the minor role of the casing for nourishing the crop. The techniques employed in this study provide a holistic and detailed characterization of the changing microbial composition in commercial champignon substrates. The knowledge generated will contribute to improve compost formulations (selection of base materials) and accelerate compost production, for instance, through biotechnological interventions in the form of tailored biostimulants and to design environmentally sustainable bio-based casing materials.  相似文献   
89.

Biodecolorization and biodegradation of azo dyes are a challenge due to their recalcitrance and the characteristics of textile effluents. This study presents the use of Halomonas sp. in the decolorization of azo dyes Reactive Black 5 (RB5), Remazol Brilliant Violet 5R (RV5), and Reactive Orange 16 (RO16) under high alkalinity and salinity conditions. Firstly, the effect of air supply, pH, salinity and dye concentration was evaluated. Halomonas sp. was able to remove above 84% of all dyes in a wide range of pH (6–11) and salt concentrations (2–10%). The decolorization efficiency of RB5, RV5, and RO16 was found to be ≥ 90% after 24, 13 and 3 h, respectively, at 50 mg L−1 of dyes. The process was monitored by HPLC-DAD, finding a reduction of dyes along the time. Further, Halomonas sp. was immobilized in volcanic rocks and used in a packed bed reactor for 72 days, achieving a removal rate of 3.48, 5.73, and 8.52 mg L−1 h−1, for RB5, RV5 and RO16, respectively, at 11.8 h. The study has confirmed the potential of Halomonas sp. to decolorize azo dyes under high salinity and alkalinity conditions and opened a scope for future research in the treatment of textile effluents.

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