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91.
Antibody titers to several heat shock proteins (anti-Hsps) have been reported to be associated with the severity and progression of cardiovascular disease. However, there are little data regarding anti-Hsp27 titers in patients with coronary artery disease (CAD). A total of 400 patients with suspected CAD were recruited. Based on the results of coronary angiography, these patients were classified into CAD+ (n = 300) and CAD (n = 100) groups defined as patients with ≥50% and <50% stenosis of any major coronary artery, respectively. Eighty-three healthy subjects were also recruited as the control group. Serum anti-Hsp27 IgG titers were measured using an in-house enzyme-linked immunosorbent assay. CAD+ patients had significantly higher anti-Hsp27 titers compared with both CAD and control groups. Anti-Hsp27 titers were also higher in the CAD group compared with the control group. With regard to the number of affected vessels in the CAD+ group, patients with three-vessel disease had higher anti-Hsp27 titers compared with both two-vessel disease (2VD) and one-vessel disease (1VD) subgroups. However, there was no significant difference between 1VD and 2VD subgroups. In multiple linear regression analysis, the number of narrowed vessels and smoking were significant independent determinants of serum anti-Hsp27 titers. The present findings indicate that serum anti-Hsp27 titers may be associated with the presence and severity of coronary artery disease.  相似文献   
92.
It was previously reported that tumour samples had shorter telomeres than the surrounding normal tissue. Hereby, the initial sign of correlation between malignant tissue and telomere behaviour could be noticed. Bridging knowledge between germ and somatic cells could facilitate understanding cellular evolution. The aim of our investigation was to provide evidence for the evolutionary hypothesis of TL (telomere length) in primary BC (breast cancer) and BTs (brain tumours), which might be applied as a prognostic and/or predictive marker. DNA extraction from the frozen tissues was performed using high pure PCR template preparation kit. Standard protocol of Telo TTAGGG Telomere Length Assay kit, a non‐radioactive chemiluminescent assay, was used. The protein expression in extracted cells was analysed by immunofluorescence. We also detected telomerase activity. The G/T (genomic/tumour ratio) for TL in two groups of patients affected with primary BC and primary BT revealed significant differences in both BC patients (P=0.025) and in BTs (P=0.001). The pattern of telomere signals by Q‐FISH (quantitative fluorescent in situ hybridization) show that in all samples, except one, SI (signal intensity) has been significantly decreased in tissue related to blood, either in BC patients or in patients with BTs (0.041≥P≥0.001). However, the data achieved by Q‐FISH support the results of Southern blot. These data reflect a significant diversity either in BC or in BT patients, providing evidence for the evolutionary hypothesis of TL in cancer development and progression.  相似文献   
93.
94.
Essential tremor (ET) is a complex genetic disorder for which no causative gene has been found. Recently, a genome-wide association study reported that two variants in the LINGO1 locus were associated to this disease. The aim of the present study was to test if this specific association could be replicated using a French-Canadian cohort of 259 ET patients and 479 ethnically matched controls. Our genotyping results lead us to conclude that no association exists between the key variant rs9652490 and ET (Pcorr = 1.00).  相似文献   
95.
96.
Recombinant PCR has been used to generate linear fragments for promoter replacement by transformation in Aspergillus nidulans. A cassette vector carrying the pyr-4 non-homologous selectable marker and conditional promoter Pr-alcA was constructed for use as a template for PCR, and is suitable for testing the function of essential genes. Two genes involved in polar growth, cotA and bemA, were used to assess the system. Efficient targeting was possible with both genes using approximately 500bp of flanking homologous sequence. Depending on yield, the linear PCR product could be used directly for transformation, or after first cloning into a suitable vector. bemA, a putative homologue of the Saccharomyces cerevisiae BEM1 gene was identified through sequence comparison. In A. nidulans, this protein appears to have a similar role to the yeast Bem1p, which acts as a scaffold protein involved in the establishment of cell polarity.  相似文献   
97.
A series of N-(5-benzylthio-1,3,4-thiadiazol-2-yl) and N-(5-benzylsulfonyl-1,3,4-thiadiazol-2-yl) derivatives of piperazinyl quinolones was synthesized and evaluated for antibacterial activity against Gram-positive and Gram-negative microorganisms. Some of these derivatives exhibit high activity against Gram-positive bacteria; Staphylococcus aureus and Staphylococcus epidermidis, comparable or more potent than their parent N-piperazinyl quinolones norfloxacin and ciprofloxacin as reference drugs. The SAR of this series indicates that both the structure of the benzyl unit and the S or SO(2) linker dramatically impact antibacterial activity.  相似文献   
98.
Efficient oxidation of Hantzsch 1,4-dihydropyridines to their corresponding pyridine derivatives with (Bu(4)N)IO(4) catalyzed by tetraphenylporphyrinatomanganese(III) chloride [Mn(TPP)Cl] is reported. This catalytic system shows high efficiency in the oxidation of 1,4-dihydropyridines at room temperature in the presence of imidazole.  相似文献   
99.
To determine the role of superoxide (O(2)(-)) formation in the kidney during alterations in the renin-angiotensin system, we evaluated responses to the intra-arterial infusion of an O(2)(-) - scavenging agent, tempol, in the denervated kidney of anesthetized salt-depleted (SD, n=6) dogs and salt-replete (SR, n=6) dogs. As expected, basal plasma renin activity was higher in SD than in SR dogs (8.4 +/- 1.0 vs. 2.3 +/- 0.6 ng angiotensin 1/ml/hr). Interestingly, the basal level of urinary F(2)-isoprostanes excretion (marker for endogenous O(2)(-) activity) relative to creatinine (Cr) excretion was also significantly higher in SD compared to SR dogs (9.1 +/- 2.8 vs. 1.6 +/- 0.4 ng F(2)-isoprostanes/mg of Cr). There was a significant increase in renal blood flow (4.3 +/- 0.5 to 4.9 +/- 0.6 ml/min/g) and decreases in renal vascular resistance (38.2 +/- 5.8 to 33.2 +/- 4.7 mm Hg/ml/min/g) and mean systemic arterial pressure (148 +/- 6 to 112 +/- 10 mm Hg) in SD dogs but not in SR dogs during infusion of tempol at 1 mg/kg/min for 30 mins. Glomerular filtration rate and urinary sodium excretion (U(Na)V) did not change significantly during tempol infusion in both groups of dogs. Administration of the nitric oxide synthase inhibitor nitro-L-arginine (50 mug/kg/min) during tempol infusion caused a reduction in U(Na)V in SR dogs (47% +/- 12%) but did not cause a decrease in SD dogs. These data show that low salt intake enhances O(2)(-) activity that influences renal and systemic hemodynamics and thus may contribute to the regulation of arterial pressure in the salt-restricted state.  相似文献   
100.
Saccharomyces cerevisiae Scc2 binds Scc4 to form an essential complex that loads cohesin onto chromosomes. The prevalence of Scc2 orthologs in eukaryotes emphasizes a conserved role in regulating sister chromatid cohesion, but homologs of Scc4 have not hitherto been identified outside certain fungi. Some metazoan orthologs of Scc2 were initially identified as developmental gene regulators, such as Drosophila Nipped-B, a regulator of cut and Ultrabithorax, and delangin, a protein mutant in Cornelia de Lange syndrome. We show that delangin and Nipped-B bind previously unstudied human and fly orthologs of Caenorhabditis elegans MAU-2, a non-axis-specific guidance factor for migrating cells and axons. PSI-BLAST shows that Scc4 is evolutionarily related to metazoan MAU-2 sequences, with the greatest homology evident in a short N-terminal domain, and protein–protein interaction studies map the site of interaction between delangin and human MAU-2 to the N-terminal regions of both proteins. Short interfering RNA knockdown of human MAU-2 in HeLa cells resulted in precocious sister chromatid separation and in impaired loading of cohesin onto chromatin, indicating that it is functionally related to Scc4, and RNAi analyses show that MAU-2 regulates chromosome segregation in C. elegans embryos. Using antisense morpholino oligonucleotides to knock down Xenopus tropicalis delangin or MAU-2 in early embryos produced similar patterns of retarded growth and developmental defects. Our data show that sister chromatid cohesion in metazoans involves the formation of a complex similar to the Scc2-Scc4 interaction in the budding yeast. The very high degree of sequence conservation between Scc4 homologs in complex metazoans is consistent with increased selection pressure to conserve additional essential functions, such as regulation of cell and axon migration during development.  相似文献   
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