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61.
Tumor cell-derived factors, such as interleukin 10 (IL-10), polarize macrophages toward a regulatory M2 phenotype, characterized by the expression of anti-inflammatory cytokines and protumorigenic mediators. Here we explored molecular mechanisms allowing IL-10 to upregulate the protumorigenic protein NGAL in primary human macrophages. Reporter assays of full-length or deletion constructs of the NGAL promoter provided evidence that NGAL production is STAT3 dependent, activated downstream of the IL-10-Janus kinase (Jak) axis, as well as being C/EBPβ dependent. The involvement of STAT3 and C/EBPβ was shown by chromatin immunoprecipitation (ChIP) and ChIP-Western analysis, as well as decoy oligonucleotides scavenging both STAT3 and C/EBPβ in human macrophages. Furthermore, the production of NGAL in macrophages in response to IL-10 induces cellular growth and proliferation of MCF-7 breast cancer cells. We conclude that both STAT3 and C/EBPβ are needed to elicit IL-10-mediated NGAL expression in primary human macrophages. Macrophage-secreted NGAL shapes the protumorigenic macrophage phenotype to promote growth of MCF-7 breast cancer cells. Our data point to a macrophage-dependent IL-10-STAT3-NGAL axis that might contribute to tumor progression.  相似文献   
62.
The purpose of this study was to ascertain whether vitamin C supplementation during chronic exercise training alters rat brain antioxidant content. Female Wistar albino rats were exercised on a treadmill for 30 min/day for 6.5 weeks and were administered daily intraperitoneal injections of vitamin C (20 mg/kg). After the training period, chronically exercised rats showed no significant changes in total brain thiobarbituric acid reactive substances (TBARS) levels. In contrast, rats supplemented with vitamin C during the training period showed significantly elevated brain TBARS levels. If such results were extrapolated to man, where vitamin supplementation is a common practice, this would indicate that vitamin C supplementation may not protect brain tissue against exercise-induced oxidative damage, in such circumstances, this water-soluble antioxidant behaves as a pro-oxidant. (Mol Cell Biochem xxx: 135–138, 2005)  相似文献   
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Analysis of affective picture processing by means of EEG has invaded the literature. The methodology of event-related EEG coherence is one of the essential methods used to analyze functional connectivity. The aims of the present study are to find out the long range EEG connectivity changes in perception of different affective pictures and analyze gender differences in these long range connected networks. EEGs of 28 healthy subjects (14 female) were recorded at 32 locations. The participants passively viewed emotional pictures (IAPS, unpleasant, pleasant, neutral). The long-distance intra-hemispheric event-related coherence was analyzed for delta (1–3.5 Hz), theta (4–7.5 Hz), and alpha (8–13 Hz) frequency ranges for F3–T7, F4–T8, F3–TP7, F4–TP8, F3–P3, F4–P4, F3–O1, F4–O2, C3–O1, C4–O2 electrode pairs. Unpleasant pictures elicited significantly higher delta coherence values than neutral pictures (p < 0.05), over fronto-parietal, fronto-occipital, and centro-occipital electrode pairs. Furthermore, unpleasant pictures elicited higher theta coherence values than pleasant (p < 0.05) and neutral pictures (p < 0.05). The present study showed that female subjects had higher delta (p < 0.05) and theta (p < 0.05) coherence values than male subjects. This difference was observed more for emotional pictures than for neutral pictures. This study showed that the brain connectivity was higher during emotional pictures than neutral pictures. Females had higher connectivity between different parts of the brain than males during emotional processes. According to these results, we may comment that increased valence and arousal caused increased brain activity. It seems that not just single sources but functional networks were also activated during perception of emotional pictures.  相似文献   
65.
Phe-Tyr dipeptide which was investigated in Wakame food with greatest ACE-inhibitory activity is used as a pharmaceutical drug for the treatment of hypertension, cardiovascular diseases, and diabetic nephropathy. To improve the bioavailability of Phe-Tyr, a delivery system based on poly (lactic-co-glycolic acid) (PLGA) nanoparticles loaded with Phe-Tyr (Phe-Tyr-PLGA NPs) for treating hypertension and cardiovascular diseases was prepared in this study. In the experiments, poly(lactic-co-glycolic acid) (PLGA) and Phe-Tyr dipeptide-loaded PLGA nanoparticles were prepared using the double emulsion (w/o/w) method. The characterizations of the nanoparticles were performed with a UV–vis spectrometer, the Zeta-sizer system, and FTIR spectrometer. The optimum size of the Phe-Tyr dipeptide-loaded PLGA nanoparticle was obtained with a 213.8 nm average particle size, and a 0.061 polydispersity index, ?19.5 mV zeta potential, 34% of loaded and 90.09% of encapsulation efficiency. From TEM analysis, it was clearly seen that the dipeptide loaded nanoparticles had the spherical and non-aggregated morphology and Phe-Tyr dipeptide loaded-PLGA nanoparticles were obtained successfully. Cell toxicity of nanoparticles at different concentrations was assayed with XTT methods on L929 fibroblast cells. This study determined that the nanoparticles have low toxicity at lower concentration and toxicity augmented with increasing concentration of dipeptide. To analyze the effect of solvents on structure of Phe-Tyr, Molecular dynamics simulation was performed with GROMACS program and molecular orbital calculations were carried out to obtain structural and electronic properties of dipeptide. Moreover, molecular docking calculations were also employed to model and predict protein–drug interactions.  相似文献   
66.
The aerial parts of Turkish Fumaria vaillantii yielded 26 isoquinoline alkaloids. Of these, oxysanguinarine, (±)-8-acetonyldihydrosanguinarine, (±)-8-methoxydihydrosanguinarine and fumaramidine are reported for the first time from this plant. New alkaloids for the genus Fumaria are dihydrosanguinarine, norsanguinarine, (+)-isocorydine, (?)-corledine and (+)-juziphine. This is the first occurrence of the isoquinolone N-methylcorydaldine in a member of the Fumariaceae. Spectral data are given for the new compound, E-fumaramine.  相似文献   
67.
In Turkish population, plasma HDL‐C levels were found to be lower than in any other country and it is suggested that this is associated with genetic origin. The cholesteryl ester transfer protein (CETP) ?629C > A polymorphism is associated with lower plasma CETP concentration, with increased HDL‐C level. In the present study, the frequency of ?629C > A polymorphism in patients with coronary artery disease (CAD) was investigated and the effect of genotype on HDL‐C was evaluated in a Turkish population. For this aim CETP ?629C > A polymorphism was studied in angiographically documented CAD patients and healthy controls. There was no statistical significance in the distribution of genotypes between patients and controls. Although A allele carriers with CAD had significantly lower HDL‐C levels than controls, plasma lipid levels showed no difference according to the genotypes. Adjustment by a logistic regression model predicting CAD status through HDL‐C and including some risk factors as covariate indicated that the HDL‐C doesn't have a significant association with CAD risk in CA and AA genotype carriers. Smoking, gender and hypertension were the common predictors for the HDL‐C levels in CA and AA carriers. Although HDL‐C appeared to be the only significant predictor of CAD in our study groups, the contribution of CETP ?629C > A polymorphism to the alterations in HDL‐C level appears to be weak to mention a protective effect of this polymorphism for CAD. In conclusion, the findings of the present study indicate that the CETP ?629C > A polymorphism is not among the determinants of the coronary artery disease in Turks. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
68.
Elevated intraocular pressure (IOP) is a major risk factor for glaucoma and is influenced by genetic and environmental factors. Recent genome-wide association studies (GWAS) reported associations with IOP at TMCO1 and GAS7, and with primary open-angle glaucoma (POAG) at CDKN2B-AS1, CAV1/CAV2, and SIX1/SIX6. To identify novel genetic variants and replicate the published findings, we performed GWAS and meta-analysis of IOP in >6,000 subjects of European ancestry collected in three datasets: the NEI Glaucoma Human genetics collaBORation, GLAUcoma Genes and ENvironment study, and a subset of the Age-related Macular Degeneration-Michigan, Mayo, AREDS and Pennsylvania study. While no signal achieved genome-wide significance in individual datasets, a meta-analysis identified significant associations with IOP at TMCO1 (rs7518099-G, p = 8.0 × 10?8). Focused analyses of five loci previously reported for IOP and/or POAG, i.e., TMCO1, CDKN2B-AS1, GAS7, CAV1/CAV2, and SIX1/SIX6, revealed associations with IOP that were largely consistent across our three datasets, and replicated the previously reported associations in both effect size and direction. These results confirm the involvement of common variants in multiple genomic regions in regulating IOP and/or glaucoma risk.  相似文献   
69.
The present study was conducted to evaluate the serum selenium levels in first-degree relatives of diabetic patients (FDR) according to controls. Insulin resistance, serum lipid levels, inflammation markers, and blood pressure were also studied in these patients. Serum levels of selenium in FDR were significantly lower than control group (74.65 ± 5.9 vs 88.7 ± 8.7 μg/dl, p < 0.0001). HsCRP, HOMA-IR, insulin, homocysteine levels were significantly higher in FDR according to the control group (1.32 ± 0.9 vs 0.63 ± 0.4 mg/dL, p < 0.0001; 2.07 ± 0.84 vs 1.51 ± 0.69, p < 0.0001; 9.26 ± 3.8 vs 6.8 ± 2.98 μU/MI, p < 0.0001; 15.7 ± 7.4 vs 11.5 ± 5.1 μmol/L, p < 0.0001, respectively). There was significant correlation between selenium levels and hsCRP (r = − 0.450, p < 0.0001). There was also weak significant correlation also between HOMA-IR and selenium levels (r = −0.227, p = 0.003). There was a correlation between systolic blood pressure and BMI (r = 0.365, p < 0.0001). But there was no correlation between selenium levels and blood pressure or other parameters. HsCRP, HOMA-IR, homocysteine levels in individuals with selenium levels < 80 μg/L (n = 78) was significantly higher than hsCRP HOMA-IR, homocysteine levels in individuals with selenium levels ≥ 80 (n = 91; 1.23 ± 0.98 vs 0.81 ± 0.76 mg/dL, p < 0.003; 1.99 ± 0.88 vs 1.64 ± 0.74, p < 0.005; 15.0 ± 7.6 vs 12.9 ± 5.7 μmol/L, p < 0.049, respectively). Selenium deficiency may contribute to cardiovascular disease risk in FDR.  相似文献   
70.
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