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101.
Inhibitors of the programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) immune checkpoint system are used for treating various malignancies. However, evidence on their use in soft tissue sarcomas (STS) is limited. This study aimed to retrospectively investigate the relationship between the expression of PD-1/PD-L1 and related antigens in STS, and their association with clinical characteristics. Immunostaining for CD4, CD8, PD-1, PD-L1, IL-2, and IFN-γ was performed using pathological specimens harvested at the time of biopsy from 10 patients with undifferentiated pleomorphic sarcoma (UPS), nine with myxofibrosarcoma (MFS), and three with malignant peripheral nerve sheath tumor (MPNST) who were treated at our hospital. Subsequently, the positive immunostaining cell rates were calculated. We also examined the correlation between each immune positive cell rate and age, tissue grade, size, and maximum standardized uptake (SUV-max) values. The 3-year event-free survival (EFS) and overall survival (OS) rates were compared between the positive and negative groups (positive rate >10%; negative <10%) for various immune stains. The positive rates were also compared between the presence and absence of events groups. There was positive staining for the immune checkpoint molecules in every STS type except for PD-1 in MPNST. CD4, CD8, and PD-1 stained lymphocytes in close proximity to the tumor in adjacent tissue sections. A positive correlation was observed between the positive cell rates of each immune component including inflammatory cytokines such as IL-2 and IFN-γ. Additionally, the clinical features positively correlated with the positive PD-1/PD-L1 expression rates. No significant differences in the 3-EFS and OS rates were observed between the PD-1/PD-L1 positive and negative groups. Our results suggest that an inducible immune checkpoint mechanism may be involved in UPS, MFS, and MPNST.Key words: Immune checkpoint inhibitors, PD-1/PD-L1, soft tissue sarcoma, programmed death-1, programmed death-ligand 1  相似文献   
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Isoniazid (INH) has neurotoxic effects such as seizure, poor concentration, subtle reduction in memory, anxiety, depression and psychosis. INH-induced toxic effects are thought to be through increased oxidative stress, and these effects have been shown to be prevented by antioxidant therapies in various organs. Increased oxidative stress may be playing a role in these neurotoxic effects. N-methyl D-aspartat receptors (NMDA) are a member of the ionotropic group of glutamate receptors. These receptors are involved in a wide variety of processes in the central nervous system including synaptogenesis, synaptic plasticity, memory and learning. Erdosteine is a potent antioxidant and mucolytic agent. We aimed to investigate adverse effects of INH on rat hippocampal NMDAR receptors, and to elucidate whether erdosteine prevents possible adverse effects of INH. In the present study, compared to control group, NMDAR2A (NR2A) receptors were significantly decreased and malondialdehyde (MDA), end product of lipid peroxidation, production was significantly increased in INH-treated group. On the other hand, administration of erdosteine to INH-treated group significantly increased NR2A receptors and decreased MDA production. In conclusion, decreasing NR2A receptors in hippocampus and increasing lipid peroxidation correlates with the degree of oxidative effects of INH and erdosteine protects above effect of INH on NR2A receptors and membrane damage due to lipid peroxidation by its antioxidant properties.  相似文献   
105.
Multiple myeloma (MM) is a neoplastic disorder characterized by monoclonal multiplying of plasma cells. Although radiation, environmental factors, viruses and other factors have been suggested as potential causes of the disease, the aetiopathogenesis of MM is still obscure. This clinical study was designed to investigate the role of reactive oxygen species (ROS) in the aetiopathogenesis of the disease and the possible relationships between treatment and ROS production. For this purpose, erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities as well as plasma nitric oxide (NO) and malondialdehyde (MDA) levels were measured in 14 MM patients newly diagnosed at stage III. The relationship between the above-mentioned parameters and vincristine-adriamycin-dexamethasone (VAD) therapy were also investigated in the same patients. All the enzyme activities and the parameters of oxidative stress were found to be significantly reduced after VAD therapy. These findings suggest that ROS may be involved in the aetiopathogenesis of MM. Further investigations with a larger cohort of MM patients are needed to provide definitive data about the role of ROS in MM and the alternative therapeutic approaches to MM.  相似文献   
106.
It is difficult to understand precisely the physiological actions of herbs because they contain a complex array of constituent molecules. In the present study we used DNA microarray data for 12600 genes to examine the anti-proliferative activity of the herb Coptidis rhizoma and eight constituent molecules against eight human pancreatic cancer cell lines. We identified 27 genes showing strong correlation with the 50% inhibitory dose (ID50) of C. rhizoma after 72-h exposure. Hierarchical cluster analysis with correlation coefficients between expression levels of these 27 C. rhizoma-related genes and the ID50 of each constituent molecule classified these test molecules into two clusters, one consisting of C. rhizoma and berberine and the other consisting of the remaining seven molecules. Our results suggest that one molecule, berberine, can account for the majority of the anti-proliferative activity of C. rhizoma and that DNA microarray analyses can be used to improve our understanding of the actions of an intact herb.  相似文献   
107.
The purpose of this study was to investigate the effect of cool exposure on lipolytic response during prolonged intermediate-intensity exercise in humans. Eight male subjects participated in this study; they performed 120-min cycle ergometer exercise at 60% of maximal oxygen uptake (VO2max) in a climatic chamber at 10 degrees C (C) and 30 degrees C (WH). There were no significant differences in oxygen uptake and respiratory exchange ratio between the two conditions during the prolonged exercise. Significant influences of cool exposure were observed in the changes in both heart rate and rectal temperature (p<0.01). Although cool exposure had no significant effects on plasma triglyceride, free fatty acid, and glycerol levels, changes in adrenaline and noradrenaline levels at C were significantly lower than WH during the prolonged exercise (p<0.01). Changes in the ratio of glycerol to noradrenaline (Gly/Nad), as an index of lipolytic efficiency, were significantly high at C as compared with WH (p<0.01). These results suggest that cool exposure has an influence on lipid metabolism during prolonged intermediate-intensity exercise, from the viewpoint of efficiency in lipolysis.  相似文献   
108.
The ClpX chaperone modulates assembly of the tubulin-like protein FtsZ   总被引:4,自引:1,他引:3  
Summary Assembly of the tubulin-like cytoskeletal protein FtsZ into a ring structure establishes the location of the nascent division site in prokaryotes. Factors that modulate FtsZ assembly are essential for ensuring the precise spatial and temporal regulation of cytokinesis. We have identified ClpX, the substrate recognition subunit of the ClpXP protease, as an inhibitor of FtsZ assembly in Bacillus subtilis. Genetic data indicate that ClpX but not ClpP inhibits FtsZ-ring formation in vivo. In vitro, ClpX inhibits FtsZ assembly in a ClpP-independent manner through a mechanism that does not require ATP hydrolysis. Together our data support a model in which ClpX helps maintain the cytoplasmic pool of unassembled FtsZ that is required for the dynamic nature of the cytokinetic ring. ClpX is conserved throughout bacteria and has been shown to interact directly with FtsZ in Escherichia coli. Thus, we speculate that ClpX functions as a general regulator of FtsZ assembly and cell division in a wide variety of bacteria.  相似文献   
109.
An inhibitor of the complex of factor VIIa and tissue factor (fVIIa/TF), 2-substituted-4-amidinophenylpyruvic acid 1a, was structurally modified with the aim of increasing its potency and selectivity. The lead compound 1a was originally found in our factor Xa (fXa) inhibitor library on the basis of structural similarity of the primary binding sites of fVIIa and fXa. The design was based on computational docking studies using the extracted active site of fVIIa. Compound 1j was found to inhibit factor VIIa/TF at nanomolar concentration with improved selectivity versus fXa and thrombin and it preferentially prolonged the clotting time in the TF-dependent extrinsic pathway.  相似文献   
110.
We have previously detected two brain-specific and development-dependent N-glycans [H. Shimizu, K. Ochiai, K. Ikenaka, K. Mikoshiba, and S. Hase (1993) J. Biochem. 114, 334-338]. In the present study we attempted to analyze specific N-glycans detected in neurological mutant mice. N-glycans in cerebrum and cerebellum obtained from 3-week-old neurological mutant mice (jimpy, staggerer, and shiverer) were compared with those obtained from normal mice. N-glycans liberated from the cerebrum and cerebellum by hydrazinolysis-N-acetylation were pyridylaminated, and pyridylamino derivatives of N-glycans thus obtained were separated into neutral and five acidic fractions by anion exchange chromatography. PA-N-glycans in each fraction were compared with those obtained from normal mice by reversed-phase HPLC, and the following results were obtained. The ratio of the two brain-type N-glycans, Manalpha1-3(GlcNAcbeta1-2Manalpha1-6)(GlcNAcbeta1-4)Manbeta1-4GlcNAcbeta1-4(Fucalpha1-6)GlcNAc (BA-1) to GlcNAcbetaManalpha1-3(GlcNAcbeta1-2Manalpha1-6)(GlcNAcbeta1-4)Manbeta1-4GlcNAcbeta1-4(Fuca1-6)GlcNAc (BA-2), was higher in staggerer mice than other mutant mice and normal mice. Sia-Gal-BA-2, triantennary N-glycans, and bisected biantennary N-glycans were found in the cerebellum of shiverer and staggerer mice but not in normal or jimpy mice. High-mannose type N-glycans were not altered in mutant mice brains. The amounts of disialylbiantennary N-glycans and disialylfucosylbiantennary N-glycans were lower in jimpy mouse cerebellum than in normal mouse cerebellum, but were higher in shiverer mouse. Some alterations of N-glycans specific to mutations were successfully identified, suggesting that expression of component(s) of the N-glycan biosynthetic pathway was specifically affected in neurological mutations.  相似文献   
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