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41.
Most patients with Parkinson's disease (PD) have sporadic form of the disease with a multifactorial etiology due to interactions between environmental conditions and the genetic constitution of the individuals. We have analyzed by APEX technology 50 single nucleotide polymorphisms (SNPs) in 19 genes related to cholecystokinin, serotonin, dopamine and opioid neurotransmission. Significant differences in the allele and genotype frequencies between the controls and PD patients were detected for four SNPs from three genes (serotonin 2A receptor (rs6311, P = 0.043), Wolfram syndrome 1 (rs1801211, P = 0.007), proopiomelanocortin (rs28930368, P = 0.026 and rs2071345, P = 0.027) genes). Two SNPs in proopiomelanocortin (POMC) gene were also associated with different clinical forms of PD. Our data suggest that at least three genes involved in neurotransmitter systems may have more specific role in genetic predisposition to PD.  相似文献   
42.
In the direct C–H arylation with arylhalogenides in the presence of Pd(OAc)2, trifluoromethyl-containing antipyrine reacts very slowly and incompletely owing to the low nucleophilicity of its C4 center. However, it was effective in modifying polyfluoroalkyl-substituted 4-bromo- and 4-iodo antipyrines by the Suzuki and Sonogashira reactions. It was established that using Pd2(dba)3 as catalyst and XPhos as phosphine ligand was the optimal catalytic system for the synthesis of 4-aryl- and 4-phenylethynyl-3-polyfluoroalkyl-antipyrines. Moreover, iodo-derivatives as the initial reagents were found to be more advantageous compared to bromo-containing analogs. It was found that 4-phenylethynyl-5-CF3-antipyrine has a moderate activity against the influenza virus A/Puerto Rico/8/34 (H1N1) and 4-iodo-5-CF3-antipyrine reveals a weak activity against the vaccine virus (strain Copenhagen) and bovine diarrhea virus (strain VC-1).

Peculiarities of heterocyclic systems with electron-withdrawing groups (polyfluoroalkyl-containing antipyrines) in Pd-catalyzed C–H arylation and cross-coupling reactions.  相似文献   
43.
Semax is a synthetic peptide consisting of the ACTH fragment (4–7) and the C-terminal Pro-Gly-Pro peptide. It promotes neuron survival during hypoxia and increases selcective attention and memory consolidation. It has been shown that semax influences the expression of some genes, particularly nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF). In the present study, we performed an analysis of the time course of the expression of NGF and BDNF genes in the hippocampus and frontal cortex in rats after a single intranasal administration of semax at a dose of 50 μg/kg. We found that semax administration resulted in a rapid long-term activation of the NGF and BDNF genes expression, which was specific for different rat brain structures investigated.  相似文献   
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Previous studies have shown that synthetic tuftsin analogue Selank and its fragments cause a number of alterations in the expression of certain genes involved in inflammation in mouse spleen. In this work we studied the effect of Selank and its short fragment Gly-Pro on the temporary dynamics of C3, Casp1, Il2rg, and Xcr1 genes expression in mouse spleen after single intraperitoneal injection (100 μg/kg) of peptides using real-time PCR method. We found a significant 3-fold decrease in the C3 mRNA level just 30 min after Selank injection and similar alteration this gene mRNA level after Gly-Pro administration. A wave-like alteration in the Casp1 mRNA level was observed after Selank injection. We found a significant alteration in the mRNA level of the Il2rg gene at early time points after Selank and Gly-Pro administration and an almost equal reduction in the Xcr1 mRNA level 90 min after the administration of Selank and its fragment. Our results showed that, Selank and its short fragment Gly-Pro influence the expression of genes that mediate different types of immune responses, thereby maintaining the balance of the immune system. It should be noted that in most cases, there was a coincidence in the expression profiles of the studied genes after Selank and Gly-Pro administration. This might indicate an active contribution of the dipeptide to the final effect of Selank.  相似文献   
47.

Background

Residing in greener places may be protective against diabetes mellitus (DM) but evidence is scarce and comes mainly from developed countries.

Objectives

To investigate associations of residential greenness with DM prevalence and glucose-homeostasis markers in Chinese adults and whether these associations were mediated by air pollution, physical activity, and body mass index.

Methods

In 2009, a total of 15,477 adults from the cross-sectional 33 Communities Chinese Health Study provided blood samples and completed a questionnaire. We considered fasting and 2-h glucose and insulin concentrations, as well as the homoeostasis model assessment of insulin resistance and β-cell function, as glucose-homeostasis markers. DM was defined according to the American Diabetes Association's recommendations. Residential greenness was estimated by two satellite-derived vegetation indexes – Normalized Difference Vegetation Index (NDVI) and Soil Adjusted Vegetation Index (SAVI). Nitrogen dioxide and particulate matter ≤2.5?μm were used as air pollution proxies. Associations were assessed by two-level adjusted logistic and linear regression models.

Results

A 0.1-unit increase in NDVI500 m and SAVI500 m was significantly associated with lower odds of DM by factors of 0.88 (95% Confidence Interval 0.82–0.94) and 0.80 (0.72–0.90), respectively. Higher greenness was also significantly associated with lower fasting and 2-h glucose levels, 2-h insulin level, as well as lower insulin resistance and higher β-cell function. Air pollution and body mass index significantly mediated 6.9–51.1% and 8.6–78.7% these associations, respectively, while no mediation role was observed for physical activity.

Conclusions

Higher residential greenness appears to be associated with a lower prevalence of DM. This association might be due to glucose and insulin metabolism and pancreatic β-cell function. Lower levels of air pollution and body mass index can be pathways linking greenspace to diabetes.  相似文献   
48.
Clinical and Experimental Medicine - Recently, the association of polymorphism rs1800562 (p.C282Y) in the hemochromatosis (HFE) gene with the increased risk of venous ulceration was shown. We...  相似文献   
49.
Anemia in β-thalassemia is related to ineffective erythropoiesis and reduced red cell survival. Excess free heme and accumulation of unpaired α-globin chains impose substantial oxidative stress on β-thalassemic erythroblasts and erythrocytes, impacting cell metabolism. We hypothesized that increased pyruvate kinase activity induced by mitapivat (AG-348) in the Hbbth3/+ mouse model for β-thalassemia would reduce chronic hemolysis and ineffective erythropoiesis through stimulation of red cell glycolytic metabolism. Oral mitapivat administration ameliorated ineffective erythropoiesis and anemia in Hbbth3/+ mice. Increased ATP, reduced reactive oxygen species production, and reduced markers of mitochondrial dysfunction associated with improved mitochondrial clearance suggested enhanced metabolism following mitapivat administration in β-thalassemia. The amelioration of responsiveness to erythropoietin resulted in reduced soluble erythroferrone, increased liver Hamp expression, and diminished liver iron overload. Mitapivat reduced duodenal Dmt1 expression potentially by activating the pyruvate kinase M2-HIF2α axis, representing a mechanism additional to Hamp in controlling iron absorption and preventing β-thalassemia–related liver iron overload. In ex vivo studies on erythroid precursors from patients with β-thalassemia, mitapivat enhanced erythropoiesis, promoted erythroid maturation, and decreased apoptosis. Overall, pyruvate kinase activation as a treatment modality for β-thalassemia in preclinical model systems had multiple beneficial effects in the erythropoietic compartment and beyond, providing a strong scientific basis for further clinical trials.  相似文献   
50.

Objectives

We assessed a novel approach to percutaneous renal denervation for uncontrolled hypertension consisting of ablation beyond the proximal main renal artery (Y-pattern), including the primary branches, and compared it to the standard procedure applied only within the main vessel. We also assessed the safety and practicality of a brachial access approach.

Methods and results

Renal denervation was performed on 119 consecutive patients (60?±?13?years). In 68 of the patients, femoral arterial vascular approach was used and in 51 brachial. In 80 patients treated with the standard ablation, 12.0?±?3.0 total ablations (both sides) were applied while 20.4?±?3.9 total ablations were delivered for the group of 39 patients with Y-pattern denervation (P?<?0.001). Technically successful renal denervation was achieved in all patients. Office blood-pressure levels at baseline were 170?±?17/93?±?10?mm?Hg for the standard group and 169?±?13/96?±?9?mm?Hg for the Y-pattern group. No major adverse events occurred during the procedure or in the postprocedural in-hospital period. Renal denervation was associated with significant decreases in both office and ambulatory systolic and diastolic blood pressure in both groups. The reduction in 24-hour mean ambulatory systolic blood pressure at 6?months was significantly greater (P?=?0.002) for the Y-Pattern group (?22.1?±?15.4?mm?Hg) compared to the Standard group (?11.8?±?16.2?mm?Hg). Changes in diastolic office and ambulatory pressure were also significantly greater at 6?months in the Y-pattern ablation group. Indices of blood pressure variability improved in both groups.

Conclusion

Renal denervation using a Y-pattern ablation strategy combined with a greater number of lesions is safe and resulted in significant greater decreases in mean 24-hour ambulatory systolic and diastolic blood pressure compared to the conventional approach in this single-centre matched cohort study. Brachial artery access was shown to be feasible and safe for renal denervation.  相似文献   
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