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201.
Objective The “Triarchic body-pathway relaxation technique” (TBRT) is a form of ancient Chinese mindfulness-based meditation professed to give rise to positive emotions and a specific state of consciousness in which deep relaxation and internalized attention coexist. The purpose of this study was to examine the EEG pattern generated during the practice of this mindfulness exercise, and compare it to music listening which has been shown to induce positive emotions. Methods Nineteen college students (aged 19–22 years) participated in the study. Each participant listened to both the TBRT and music audiotapes while EEG was recorded. The order of presentation was counterbalanced to avoid order effect. Two EEG indicators were used: (1) alpha asymmetry index, an indicator for left-sided anterior activation, as measure of positive emotions, and (2) frontal midline theta activity, as a measure for internalized attention. Results Increased left-sided activation, a pattern associated with positive emotions, was found during both TBRT exercise and music conditions. However, only TBRT exercise was shown to exhibit greater frontal midline theta power, a pattern associated with internalized attention. Conclusions These results provided evidence to support that the TBRT gives rise to positive emotional experience, accompanied by focused internalized attention.  相似文献   
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The inhibition of cyclooxygenase enzymes plays an important role in the treatment of inflammatory diseases. N-Hydroxy-4-(5-methyl-3-phenylisoxazol-4-yl)benzenesulfonamide (3)—a primary metabolite of the highly selective COX-2 inhibitor valdecoxib—was synthesized and stabilized as its monohydrate (3a·H2O). The anti-inflammatory properties of 3a·H2O were investigated in carrageenan-induced edema and in acute and chronic pain models. Based on our biological investigation, we conclude that N-hydroxy-valdecoxib 3a is an active metabolite of valdecoxib.  相似文献   
204.
Invasion of bacteria into nonphagocytic host cells is an important pathogenicity factor for escaping the host defence system. Gram-positive organisms, for example Staphylococcus aureus and Listeria monocytogenes, are invasive in nonphagocytic cells, and this mechanism is discussed as an important part of the infection process. Uropathogenic Escherichia coli and Staphylococcus saprophyticus can cause acute and recurrent urinary tract infections as well as bloodstream infections. Staphylococcus saprophyticus shows strong adhesion to human urinary bladder carcinoma and Hep2 cells and expresses the 'Microbial Surface Components Recognizing Adhesive Matrix molecule' (MSCRAMM)-protein SdrI with collagen-binding activity. MSCRAMMs are responsible for adhesion and collagen binding in S. aureus and are discussed as an important pathogenicity factor for invasion. To investigate internalization in S. aureus, several fluorescence activated cell sorting (FACS) assays have been described recently. We used a previously described FACS assay, with slight modifications, in addition to an antibiotic protection assay and transmission electron microscopy to show that S. saprophyticus ATCC 15305 and the wild-type strain 7108 were internalized into the human urinary bladder carcinoma cell line 5637. The discovery of the internalization of S. saprophyticus may be an important step for understanding the pathogenicity of recurrent infections caused by this organism.  相似文献   
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The MSMEG_4626 gene was cloned from Mycobacterium smegmatis MC2 155. It codes for a protein of 1,037 amino acids, identified as ribonuclease E by matching to the protein family HMM TIGR00757. The protein was expressed and purified. Although its calculated molecular weight is 112.7 kDa, it has an aberrant mobility in SDS-polyacrylamide gels, like other ribonuclease E enzymes (it migrates as a 180 kDa protein). The central part of the protein displays high similarity to the catalytic domains of other RNase E enzymes. Mass spectrometric analysis revealed the presence of the chaperonin GroEL, ribosomal proteins, a negative regulator of genetic competence and GTP pyrophosphokinase in the affinity-purified preparation. It is a very unstable protein; despite the use of protease inhibitors in addition to the full-length RNase E its proteolytic fragments were detected.  相似文献   
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Antibody based manipulation of the CD137 (4‐1BB) co‐signaling pathway is an attractive option for the treatment of cancer and autoimmune disease. We developed a chimeric anti‐human CD137 monoclonal antibody (GG) and characterized its function. As a component of planned preclinical studies, we evaluated the binding of GG to activated peripheral blood mononuclear cells (PBMCs) from cynomolgus macaque and baboon against human. Interestingly, GG only recognized human CD137, while a commercial anti‐CD137 mAb (4B4‐1), recognized activated PBMCs from both human and non‐human primates (NHP). Subsequent analysis revealed that the amino acid sequence of CD137 is largely conserved between primate species (~95% identical), with the extracellular domain differing by only 9–10 amino acids. Based on these data, we generated mutant constructs in the extracellular domain, replacing NHP with human CD137 sequences, and identified 3 amino acids critical for GG binding. These residues are likely part of a conformational epitope, as a peptide spanning this region is unable to block mAb binding. These data demonstrate that subtle sequence variations of defined co‐stimulatory molecules amongst primate species can be employed as a strategy for mapping residues necessary for antibody binding to conformational epitopes. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
208.
A series of 5-vinyl-3-pyridinecarbonitriles were synthesized and evaluated as PKCθ inhibitors. The systematic optimization of 4-[(4-methyl-1H-indol-5-yl)amino]-5-[(E)-2-phenylvinyl]-3-pyridinecarbonitrile 3 resulted in the identification of compound 23e as a potent PKCθ inhibitor with good selectivity over PKCδ.  相似文献   
209.
We previously reported that a 3-pyridinecarbonitrile analog with a furan substituent at C-5 and a 4-methylindol-5-ylamino substituent at C-4, 1, was a potent inhibitor of PKCθ (IC50 = 4.5 nM). Replacement of the C-5 furan ring of 1 with bicyclic heteroaryl rings, led to compounds with significantly improved potency against PKCθ. Analog 6b with a 4-methylindol-5-ylamino group at C-4 and a 5-[(4-methylpiperazin-1-yl)methyl]-1-benzofuran-2-yl group at C-5 had an IC50 value of 0.28 nM for the inhibition of PKCθ.  相似文献   
210.
There are currently two Food and Drug Administration-approved classes of biologic agents that target tumor necrosis factor-α (TNF-α): anti-TNF monoclonal antibodies (mAbs) (adalimumab and infliximab), and soluble TNF receptors (etanercept). This study examined the ability of the TNF antagonists to: (1) bind various polymorphic variants of cell surface-expressed Fc receptors (FcγRs) and the complement component C1q, and (2) mediate Ab-dependent cellular cytotoxicity (ADCC) and complement-mediated cytotoxicity (CDC) killing of cells expressing membrane-bound TNF (mTNF) in vitro. Both mAbs and the soluble TNF receptor demonstrated low-level binding to the activating receptors FcγRI, FcγRIIa, and FcγRIIIa, and the inhibitory receptor FcγRIIb, in the absence of exogenous TNF. However, upon addition of TNF, the mAbs, but not etanercept, showed significantly increased binding, in particular to the FcγRII and FcγRIII receptors. Infliximab and adalimumab induced ADCC much more potently than etanercept. In the presence of TNF, both mAbs bound C1q in in vitro assays, but etanercept did not bind C1q under any conditions. Infliximab and adalimumab also induced CDC in cells expressing mTNF more potently than etanercept. Differences in the ability to bind ligand and mediate cell death may account for the differences in efficacy and safety of TNF antagonists.  相似文献   
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