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101.

Background

Suboptimal activation of T lymphocytes by melanoma cells is often due to the defective expression of class I major histocompatibility antigens (MHC-I) and costimulatory molecules. We have previously shown that geranylgeranyl transferase inhibition (done with GGTI-298) stimulates anti-melanoma immune response through MHC-I and costimulatory molecule expression in the B16F10 murine model [1].

Methodology/Principal Findings

In this study, it is shown that vaccination with mIFN-gand GGTI-298 pretreated B16F10 cells induces a protection against untreated tumor growth and pulmonary metastases implantation. Furthermore, using a human melanoma model (LB1319-MEL), we demonstrated that in vitro treatment with hIFN-γ and GGTI-298 led to the up regulation of MHC-I and a costimulatory molecule CD86 and down regulation of an inhibitory molecule PD-1L. Co-culture experiments with peripheral blood mononuclear cells (PBMC) revealed that modifications induced by hIFN-γ and GGTI-298 on the selected melanoma cells, enables the stimulation of lymphocytes from HLA compatible healthy donors. Indeed, as compared with untreated melanoma cells, pretreatment with hIFN-γ and GGTI-298 together rendered the melanoma cells more efficient at inducing the: i) activation of CD8 T lymphocytes (CD8+/CD69+); ii) proliferation of tumor-specific CD8 T cells (MelanA-MART1/TCR+); iii) secretion of hIFN-γ; and iv) anti-melanoma specific cytotoxic cells.

Conclusions/Significance

These data indicate that pharmacological treatment of melanoma cell lines with IFN-γ and GGTI-298 stimulates their immunogenicity and could be a novel approach to produce tumor cells suitable for vaccination and for stimulation of anti-melanoma effector cells.  相似文献   
102.
After treatment of sarcoplasmic reticulum Ca(2+)-ATPase with proteinase K (PK) in the presence of Ca(2+) and a protecting non-phosphorylated ligand (e.g. adenosine 5'-(beta,gamma-methylenetriphosphate), we were able to prepare in high yield an ATPase species that only differs from intact ATPase because of excision of the MAATE(243) sequence from the loop linking the A domain with the third transmembrane segment. The PK-treated ATPase was unable to transport Ca(2+) and to catalyze ATP hydrolysis, but it could bind two calcium ions with high affinity and react with ATP to form a classical ADP-sensitive phosphoenzyme, Ca(2)E1P, with occluded Ca(2+). The ability of Ca(2)E1P to become converted to the Ca(2+)-free ADP-insensitive form, E2P, was strongly reduced, as was the ability of PK-treated ATPase to react with orthovanadate or to form an E2P intermediate from inorganic phosphate in the absence of Ca(2+). PK-treated ATPase also reacted with thapsigargin to form a complex with altered properties, and the tryptic cleavage "T2" site in the A domain was no longer protected in the absence of Ca(2+). It is probable that disrupting the C-terminal link of the A domain with the transmembrane region severely compromises reorientation of A and P domains and the functionally critical cross-talk of these domains with the membrane-bound Ca(2+) ions.  相似文献   
103.
Plant and Soil - Phytoextraction is an in situ technique that can be applied to minerals and mining wastes using hyperaccumulator plants to purposely bio-concentrate high levels of metals or...  相似文献   
104.
105.
The built environment is the largest single emitter of CO2 and an important consumer of energy. Much research has gone into the improved efficiency of building operation and construction products. Life Cycle Assessment (LCA) is commonly used to assess existing buildings or building products. Classic LCA, however, is not suited for evaluating the environmental performance of developing technologies. A new approach, anticipatory LCA (a‐LCA), promises various advantages and can be used as a design constraint during the product development stage. It helps overcome four challenges: (i) data availability, (ii) stakeholder inclusion, (iii) risk assessment, and (iv) multi‐criteria problems. This article's contribution to the line of research is twofold: first, it adapts the a‐LCA approach for construction‐specific purposes in theoretical terms for the four challenges. Second, it applies the method to an innovative prefabricated modular envelope system, the CleanTechBlock (CTB), focusing on challenge (i). Thirty‐six CTB designs are tested and compared to conventional walls. Inclusion of technology foresight is achieved through structured scenario analysis. Moreover, challenge (iv) is tackled through the analysis of different environmental impact categories, transport‐related impacts, and thickness of the wall assemblies of the CTB. The case study results show that optimized material choice and product design is needed to reach the lowest environmental impact. Methodological findings highlight the importance of context‐specific solutions and the need for benchmarking new products.  相似文献   
106.
107.
Birds exhibit a range of wintering behaviour from strictly migrant to strictly resident species. In partially migrating ones, some birds overwinter within their breeding region (resident birds) while others, although breeding in the same area, winter far away (migrant birds). Accordingly, choosing a wintering region is a key stage in the annual life cycle of birds, notably for inexperienced first‐year individuals. The present study aimed to investigate this issue, and more specifically to study the distribution pattern during winter and factors influencing the wintering behaviour of first‐year pied avocets Recurvirostra avosetta. Based on a 10‐yr ringing study carried out on five of the major French breeding colonies distributed along the Atlantic coast, we showed the coexistence of different wintering tactics. The resident tactic was predominant (approximately 86% of the 575 birds re‐sighted), while the other birds adopted migration. Among resident individuals, two different tactics occurred: 43% of birds overwintered within their natal colony, whereas the others wintered in another site located at relatively close proximity along the French Atlantic coast. Hatching date was a consistent predictor of all wintering tactics. More specifically, the probability of migrating was the highest for early‐hatched birds, and for resident ones, the probability of wintering within their natal colony rather than in another French site was the highest for both median‐ and late‐hatched individuals. In addition, a colony effect was demonstrated for resident birds. Several biological interpretations, including social system, variations in both individual body condition and habitat quality, were put forward to explain these correlates.  相似文献   
108.
With the aim of forming bioactive guides for peripheral nerve regeneration, silk fibroin was electrospun to obtain aligned nanofibers. These fibers were functionalized by incorporating Nerve Growth Factor (NGF) and Ciliary NeuroTrophic Factor (CNTF) during electrospinning. PC12 cells grown on the fibers confirmed the bioavailability and bioactivity of the NGF, which was not significantly released from the fibers. Primary neurons from rat dorsal root ganglia (DRGs) were grown on the nanofibers and anchored to the fibers and grew in a directional fashion based on the fiber orientation, and as confirmed by growth cone morphology. These biofunctionalized nanofibers led to a 3-fold increase in neurite length at their contact, which was likely due to the NGF. Glial cell growth, alignment and migration were stimulated by the CNTF in the functionalized nanofibers. Organotypic culture of rat fetal DRGs confirmed the complementary effect of both growth factors in multifunctionalized nanofibers, which allowed glial cell migration, alignment and parallel axonal growth in structures resembling the ‘bands of Bungner’ found in situ. Graftable multi-channel conduits based on biofunctionalized aligned silk nanofibers were developed as an organized 3D scaffold. Our bioactive silk tubes thus represent new options for a biological and biocompatible nerve guidance conduit.  相似文献   
109.
Histidine protein methylation is an unusual posttranslational modification. In the yeast Saccharomyces cerevisiae, the large ribosomal subunit protein Rpl3p is methylated at histidine 243, a residue that contacts the 25S rRNA near the P site. Rpl3p methylation is dependent upon the presence of Hpm1p, a candidate seven-beta-strand methyltransferase. In this study, we elucidated the biological activities of Hpm1p in vitro and in vivo. Amino acid analyses reveal that Hpm1p is responsible for all of the detectable protein histidine methylation in yeast. The modification is found on a polypeptide corresponding to the size of Rpl3p in ribosomes and in a nucleus-containing organelle fraction but was not detected in proteins of the ribosome-free cytosol fraction. In vitro assays demonstrate that Hpm1p has methyltransferase activity on ribosome-associated but not free Rpl3p, suggesting that its activity depends on interactions with ribosomal components. hpm1 null cells are defective in early rRNA processing, resulting in a deficiency of 60S subunits and translation initiation defects that are exacerbated in minimal medium. Cells lacking Hpm1p are resistant to cycloheximide and verrucarin A and have decreased translational fidelity. We propose that Hpm1p plays a role in the orchestration of the early assembly of the large ribosomal subunit and in faithful protein production.  相似文献   
110.
DNA molecules coding either for mature porcine D-amino acid oxidase or for truncated forms of the enzyme have been obtained by stepwise addition of synthetic oligonucleotides to a partial cDNA. Under the control of the lambda PL thermoregulatable promoter, these DNAs were respectively expressed in Escherichia coli as 36, 28 and 25 kilodalton polypeptides, specifically recognised by antibodies raised against the natural enzyme. None of the truncated proteins were biologically active whereas the mature recombinant species was able to hydrolyze D-alanine in vitro as efficiently as the natural product.  相似文献   
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