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41.
Reactive oxygen and nitrogen species have been implicated in the pathogenesis of bleomycin-induced lung fibrosis. The effects of aminoguanidine and erdosteine on the bleomycin-induced lung fibrosis were evaluated in rats. The animals were placed into five groups: Vehicle + vehicle, vehicle + bleomycin (2.5 U/kg), bleomycin + aminoguanidine (200 mg/kg), bleomycin + erdosteine (10 mg/kg), and bleomycin + erdosteine + aminoguanidine. Bleomycin administration resulted in prominent lung fibrosis as measured by lung hydroxyproline content and lung histology, which is completely prevented by erdosteine and aminoguanidine. A strong staining for nitro tyrosine antibody in lung tissue and increased levels of lung NO were found in bleomycin group, that were significantly reduced by aminoguanidine and erdosteine. Aminoguanidine and erdosteine significantly prevented depletion of superoxide dismutase and glutathione peroxidase and elevated myeloperoxidase activities, malondialdehyde level in lung tissue produced by bleomycin. Data presented here indicate that aminoguanidine and erdosteine prevented bleomycin-induced lung fibrosis and that nitric oxide mediated tyrosine nitration of proteins plays a significant role in the pathogenesis of bleomycin-induced lung fibrosis. Also our data suggest that antifibrotic affect of antioxidants may be due to their inhibitory effect on nitric oxide generation in this model.  相似文献   
42.
Since overexcitation of excitatory amino acid is an important mechanism in seizure genesis wherein free radicals have recently been suggested to play a critical role, we explored the effects of caffeic acid phenethyl ester (CAPE) administration in pentylenetetrazole (PTZ)-induced seizure in mice. CAPE prevents the oxidative damage in brain tissue induced by PTZ, scavenging reactive oxygen species (ROS). Our results demonstrate that CAPE treatment which prevents free radical production and ameliorates seizure severity may be useful at least as an adjunctive treatment of seizure disorders.  相似文献   
43.
It has been proposed that the virulence of nosocomial Staphylococcus infections associated with indwelling medical devices is related to the ability of the bacterium to colonise these materials by forming a biofilm composed of multilayered cell clusters embedded in a slime matrix. However, the pathogenic role of exopolysaccharide biofilms is not fully understood. A new method was sought for differentiating the structure of slime from two closely related bacterial strains, Staphylococcus aureus and Staphylococcus epidermidis. Using PCR it was confirmed that these strains were positive for the icaA and icaD genes and the complete ica operon (2.7 kb). Monosaccharide analysis by thin-layer chromatography revealed an identical profile for both strains, with xylose and glucose present among the four visible bands. Using Fourier-transformed infrared spectroscopy and hierarchical cluster analysis, three of four S. aureus samples (75%), and four of five S. epidermidis samples were grouped according to species. A novel FTIR approach in classifying slime produced by S. aureus and S. epidermidis is reported.  相似文献   
44.
Nontyphoid salmonella (NTS) serotypes can cause gastroenteritis, bacteriemia, and focal infections. However, these focal infections, including urinary tract infections (UTI), are occasionally observed; in particular, the presence of several predisposing factors, such as immunodeficiency and structural abnormality in the urinary tract, increase the possibility of the occurrence of infection. We present a case of UTI caused by Salmonella enterica serovar Virchow in an elderly and debilitated patient with benign prostatic hyperplasia (BPH). Administration of appropriate antibiotic treatment resulted in recovery of the patient's clinical course.  相似文献   
45.
Background: The mouse double minute 2 (MDM2) gene represents one of the central nodes in the p53 pathway. A naturally occurring T/G single nucleotide polymorphism (SNP) in the intronic promoter of MDM2, SNP309 (rs2279744), was shown to influence MDM2 expression and p53 activity. SNP in the promoter region of MDM2 gene has recently been shown to be associated with accelerated tumor formation in both hereditary and sporadic cancers in humans. In this study, we aim to evaluate the association of SNP309 with the risk of hepatocellular carcinoma (HCC) development among Turkish population. Methods: MDM2 SNP309 polymorphism was investigated in 110 confirmed subjects with HCC and 110 cancer-free control subjects matched on age, gender, smoking and alcohol consumption by using a polymerase chain reaction-restriction fragment length polymorphism assay. Results: The allele frequencies of case subjects (T, 0.48; G, 0.52) were significantly different from those of control subjects (T, 0.65; G, 0.35) (p = 0.003). The proportion of GG genotype of the SNP309 in patients with HCC (26%) was significantly higher than that in patients without HCC (14%). We observed that compared with the TT genotype, the genotypes containing G allele [TG (OR, 2.19; 95% CI, 1.18–4.07; p = 0.013) or GG (OR, 3.63; 95% CI, 1.65–8.00; p = 0.001)] were associated with significant increased susceptibility to HCC. Conclusion: Our findings suggest that the MDM2 promoter SNP309 G allele is associated with presence of HCC in Turkish population.  相似文献   
46.
Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease caused by the arbovirus Crimean-Congo hemorrhagic fever virus (CCHFV). The CCHFV has a single-stranded RNA genome of negative sense. MicroRNAs (miRNAs) are key players in virus-host interactions and viral pathogenesis. We investigated the miRNA gene expression profiles in patients with CCHF using microarray for the first time in the world. Microarray analysis was performed using mirBase Ver 21 (Agilent Technologies, Santa Clara, CA). All statistical analyses were performed across the case-control, fatal-control, and fatal-nonfatal case groups using Genespring (Ver 3.0). Fifteen miRNAs were statistical significant in patients with CCHF compared with the controls (5 were upregulated, 10 were downregulated). Seventy-five and sixty-six miRNAs are in fatal compared with control and nonfatal case, respectively (fold change ([FC] ≥50) were statistically significant. In this study, the target genes of important miRNAs were identified and Gene Ontology analyses were performed across all groups. As a result of this study, we propose that the detection of miRNAs in patients with CCHF will allow the determination of therapeutic targets in diseases. CCHF is an important public health problem that can often be fatal. In this study, we investigated miRNA expression in case-control, fatal-control, and fatal-nonfatal case groups. Significant miRNAs associated with fatality were detected in CCHF. This study will serve as a source of data for the development of an antagomir-based therapy against CCHF using miRNAs in the future.  相似文献   
47.
Gentiana cruciata L. (Cross gentian) is a medicinal and ornamental plant, threatened in its natural habitats. The wild root extracts of this species are known to exhibit many curative properties. In the present study, an efficient protocol for in vitro propagation of G. cruciata L. was developed from node culture. A semi-solidified Murashige and Skoog (MS) basal medium supplemented with 2.22 μM 6-benzyladenine (BA), 2.46 μM indole-3-butyric acid (IBA) and sucrose (3% w/v) improved the production of multiple shoots directly from nodal segments, providing 3.9 shoots per explants on average. The highest rooting (81.7%) was observed with half-strength MS medium supplemented with 2.46 μM IBA. Plants with well-developed roots were transferred to pots containing turf/vermiculite mixtures and acclimatized in plant growth chamber conditions. Acclimatized plants showed 100% survival and remained healthy. The content of secondary metabolites in the clones was determined by HPLC, and the presence of gentiopicroside, loganic acid, swertiamarin, and sweroside in the samples was confirmed. Gentiopicroside was found to be the major compound.  相似文献   
48.
Severe burn injuries cause functional impairment in distant internal organs. Although this mechanism is not clear, it is possible that free radical toxicity plays an important role. Research in animals and clinical studies have shown that there is a close relationship between a lipid peroxidative reaction and secondary pathological changes following thermal injury. It has been demonstrated that antioxidant treatment prevents oxidative tissue damage associated with thermal trauma. This study was designed to determine the possible protective effect of caffeic acid phenethyl ester (CAPE) treatment against oxidative damage in the kidney and lung induced by thermal injury. Rats were decapitated either 1, 3 or 7 days after burn injury. CAPE was administered intraperitoneally immediately after thermal injury. Kidney and lung tissues were taken for the determination of malondialdehyde (MDA) level, myeloperoxidase (MPO), catalase (CAT), superoxide dismutase (SOD) and xanthine oxidase (XO) activities. Severe skin thermal injury caused a significant decrease in SOD and CAT activities, as well as significant increases in MDA level, XO and MPO activities in tissues during the postburn period. Treatment of rats with CAPE (10 micromol/kg) significantly elevated the decreased SOD and CAT activities, while it decreased MDA levels and MPO as well as XO activity.  相似文献   
49.
Abstract

It has been proposed that the virulence of nosocomial Staphylococcus infections associated with indwelling medical devices is related to the ability of the bacterium to colonise these materials by forming a biofilm composed of multilayered cell clusters embedded in a slime matrix. However, the pathogenic role of exopolysaccharide biofilms is not fully understood. A new method was sought for differentiating the structure of slime from two closely related bacterial strains, Staphylococcus aureus and Staphylococcus epidermidis. Using PCR it was confirmed that these strains were positive for the icaA and icaD genes and the complete ica operon (2.7 kb). Monosaccharide analysis by thin-layer chromatography revealed an identical profile for both strains, with xylose and glucose present among the four visible bands. Using Fourier-transformed infrared spectroscopy and hierarchical cluster analysis, three of four S. aureus samples (75%), and four of five S. epidermidis samples were grouped according to species. A novel FTIR approach in classifying slime produced by S. aureus and S. epidermidis is reported.  相似文献   
50.
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