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91.
The presence of T-wave inversion (TWI) at 12-lead electrocardiogram (ECG) in competitive athletes is one of the major diagnostic challenges for sports physicians and consulting cardiologists. Indeed, while the presence of TWI may be associated with some benign conditions and it may be occasionally seen in healthy athletes presenting signs of cardiac remodeling, it may also represent an early sign of an underlying, concealed structural heart disease or life-threatening arrhythmogenic cardiomyopathies, which may be responsible for exercise-related sudden cardiac death (SCD). The interpretation of TWI in athletes is complex and the inherent implications for the clinical practice represent a conundrum for physicians. Accordingly, the detection of TWI should be viewed as a potential red flag on the ECG of young and apparently healthy athletes and warrants further investigations because it may represent the initial expression of cardiomyopathies that may not be evident until many years later and that may ultimately be associated with adverse outcomes. The aim of this review is, therefore, to report an update of the literature on TWI in athletes, with a specific focus on the interpretation and management.  相似文献   
92.

Aims

Osteoprotegerin (OPG) is a secretory glycoprotein that belongs to the tumor necrosis factor receptor family and plays a role in atherosclerosis. OPG has been hypothesized to modulate vascular functions; however, its role in mediating atherosclerosis is controversial. Epidemiological data in patients with cardiovascular disease (CVD) indicate that OPG serum levels are associated with several inflammatory markers, myocardial infarction events, and calcium scores, suggesting that OPG may be causative for CVD.

Methods

The present study aimed to evaluate whether the OPG gene (TNFRSF11B) polymorphisms are involved in the development of peripheral arterial occlusive disease (PAOD) and critical limb ischemia (CLI) in patients with type 2 diabetes. This genetic association study included 402 diabetic patients (139 males and 263 females) with peripheral arterial occlusive disease and 567 diabetic subjects without peripheral arterial occlusive disease (208 males and 359 females). The T245G, T950C, and G1181C polymorphisms of the OPG gene were analyzed by polymerase chain reaction and restriction fragment length polymorphism.

Results

We found that the T245G, T950C, and G1181C gene polymorphisms of the OPG gene were significantly (27.9 vs. 12.2 %, P < 0.01; 33.6 vs. 10.4 %, P < 0.01 and 24.4 vs. 12.7 %, P < 0.01, respectively) and independently (adjusted OR 4.97 (3.12–6.91), OR 7.02 (4.96–11.67), and OR 2.85 (1.95–4.02), respectively) associated with PAOD. We also found that these three polymorphisms act synergistically in patients with PAOD and are associated with different levels of risk for PAOD and CLI, depending on the number of high-risk genotypes carried concomitantly by a given individual.

Conclusion

The TNFRSF11B gene polymorphisms under study are associated with PAOD, and synergistic effects between these genotypes might be potential markers for the presence and severity of atherosclerotic disorders.  相似文献   
93.
European Journal of Nuclear Medicine and Molecular Imaging - To compare the incremental diagnostic value of amyloid-PET and CSF (Aβ42, tau, and phospho-tau) in AD diagnosis in patients with...  相似文献   
94.
The aim of this in vitro study was to evaluate the interaction between ciprofloxacin and amoxicillin against beta-lactamase-producing Staphylococcus aureus. Concentration-dependent curves for each individual drug were carried out to obtain the mean inhibitory concentration in the agar well diffusion assay. Then, different ratios of the ciprofloxacin–amoxicillin combination (0.5:0.5, 0.8:0.2, 0.2:0.8, 0.9:0.1, 0.1:0.9, 0.95:0.05, and 0.05:0.95) were assessed. Data were analyzed using the isobolographic analysis and interaction index. The isobolographic evaluation shows that the 0.9:0.1 and 0.95:0.05 ratios of the ciprofloxacin–amoxicillin combination produced a synergistic antimicrobial interaction, the 0.8:0.2, 0.2:0.8, 0.1:0.9, and 0.05:0.95 proportions showed an additive antibacterial effect, and the 0.5:0.5 proportion induced antagonistic antimicrobial effects. The interaction index showed similar outcomes to the isobolographic analysis. In conclusion, the data of this study mainly show antimicrobial additive results of the ciprofloxacin–amoxicillin combination against beta-lactamase-producing S. aureus.  相似文献   
95.
96.

Background

Melanocortin 1 Receptor (MC1R) is expressed in a majority of melanoma biopsies and cell lines. We previously demonstrated that three hydrophobic low-affinity HLA-A2-restricted MC1R-derived peptides: MC1R291–298, MC1R244–252 and MC1R283–291 can elicit cytotoxic T-lymphocytes (CTL) responses from normal donor peripheral blood lymphocytes (PBL). Moreover, peptide-specific CTL recognized a panel of MHC-matched melanomas, demonstrating that human melanoma cell lines naturally present MC1R epitopes. However, the natural presence of MC1R-specific T cells in melanoma patient's tumour and blood remains unknown.

Methods

The presence of anti-MC1R specific CD8+ T cells was established in a population of melanoma-specific T cells derived from peripheral blood mononuclear cells (PBMC) and tumour-infiltrating lymphocytes (TIL) from HLA-A2+ melanoma patients.

Results

CTLs specific for the three MC1R-derived peptides that lysed allogeneic HLA-A2+MC1R+ melanomas were elicited from PBMC, demonstrating the existence of an anti-MC1R T cell repertoire in melanoma patients. Moreover, TILs also recognized MC1R epitopes and HLA-A2+ melanoma cell lines. Finally, HLA-A2/MC1R244-specific CD8+ T cell clones derived from TILs and a subset of MC1R291 specific TILs were identified using HLA-A2/MC1R tetramers.

Conclusion

Our results demonstrate that MC1R-derived peptides are common immunogenic epitopes for melanoma-specific CTLs and TILs, and may thus be useful for the development of anti-melanoma immunotherapy.  相似文献   
97.

Introduction

Intracanal disinfection is a crucial step in regenerative endodontic procedures. Most published cases suggest the use of sodium hypochlorite (NaOCl) as the primary irrigant. However, the effect of clinically used concentrations of NaOCl on the survival and differentiation of stem cells is largely unknown. In this study, we tested the effect of various concentrations of NaOCl on the stem cells of the apical papilla (SCAPs) survival and dentin sialophosphoprotein (DSPP) expression.

Methods

Standardized root canals were created in extracted human teeth and irrigated with NaOCl (0.5%, 1.5%, 3%, or 6%) followed by 17% EDTA or sterile saline. SCAPs in a hyaluronic acid–based scaffold were seeded into the canals and cultured for 7 days. Next, viable cells were quantified using a luminescence assay, and DSPP expression was evaluated using quantitative real-time polymerase chain reaction.

Results

There was a significant reduction in survival and DSPP expression in the group treated with 6% NaOCl compared with the untreated control group. Comparable survival was observed in the groups treated with the lower concentrations of NaOCl, but greater DSPP expression was observed in the 1.5% NaOCl group. In addition, 17% EDTA resulted in increased survival and DSPP expression partially reversing the deleterious effects of NaOCl.

Conclusions

Collectively, the results suggest that dentin conditioning with high concentrations of NaOCl has a profound negative effect on the survival and differentiation of SCAPs. However, this effect can be prevented with the use of 1.5% NaOCl followed by 17% EDTA. The inclusion of this irrigation regimen might be beneficial in regenerative endodontic procedures.  相似文献   
98.
Objective:To investigate the time course of osteocyte death in a mouse model of orthodontic tooth movement (OTM) and its association to the caspase-3 activation pathway and osteoclast formation.Materials and Methods:Twenty-five male wild type CD-1 mice (8–12 weeks old) were loaded with an orthodontic appliance. A spring delivering 10–12 g of force was placed between the right first molar and the incisor to displace the first molar mesially. The contralateral unloaded sides served as the control. The animals were equally divided into five different time points: 6, 12, 24, and 72 hours and 7 days of orthodontic loading. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, caspase-3 immunostaining, and tartrate-resistant acid phosphatase (TRAP) staining was performed on histologic sections of the first molars. The labeling was quantified in osteocytes on the compression side of the alveolar bone at each time point.Results:TUNEL labeling significantly increased at 12, 24, and 72 hours after orthodontic loading; the peak was observed at 24 hours. Elevated caspase-3 labeling was noted at 12, 24, and 72 hours and 7 days after loading, although the increase was not significant. Significant osteoclast formation was initially evident after 72 hours and progressively increased up to 7 days.Conclusions:Osteocyte death during OTM peaks at 24 hours, earlier than initial osteoclast activation. However, only a slight trend for increased caspase-3 activity suggests that other mechanisms might be involved in osteocyte death during OTM.  相似文献   
99.
BackgroundThe bicuspid aortic valve (BAV) affects 0.5 to 2% of the population and is associated with valve and aortic alterations. There is a lack of studies on the profile of these patients in the Brazilian population.ObjectiveTo describe the profile of patients with BAV undergoing valve and/or aortic surgery in a tertiary cardiology center, in addition to the outcomes related to the intervention.MethodsRetrospective cohort including 195 patients (mean age 54±14 years, 73.8% male) diagnosed with BAV who underwent surgical approach (valvular and/or aorta) from 2014 to 2019. Clinical data, echocardiographic and tomographic studies were evaluated, as well as characteristics of the intervention and events in 30 days. A value of p<0.05 was considered statistically significant.ResultsWe found a high prevalence of aortic aneurysm (56.5%), with a mean diameter of 46.9±10.2 mm. Major aortic regurgitation was found in 25.1% and major aortic stenosis in 54.9%. Isolated aortic valve surgery was performed in 48.2%, isolated aortic surgery in 6.7% and combined surgery in 45.1%. The 30-day mortality was 8.2%. In the multivariate analysis, the predictors of the combined outcome at 30 days (death, atrial fibrillation and reoperation) were age (OR 1.044, 95% CI 1.009-1.081, p=0.014) and left ventricular mass index (OR 1.009, 95% CI 1.000-1.018, p=0.044).ConclusionPatients with BAV approached in our service have a higher incidence of aortopathy, with the additional need to evaluate the aorta with computed tomography or magnetic resonance imaging.  相似文献   
100.
Diet is a matter of interest in the pathogenesis and management of Crohn’s Disease (CD). Little is known about CD children’s dietary habits. Our aim was assessing the quality and the amount of nutrient intake in a group of CD pediatric patients. Data were compared with those of healthy subjects (HS). In total, 20 patients (13 males) and 48 HS (24 males) aged 4–18 years were provided with a food diary to fill out for one week. Winfood software performed the bromatological analysis, providing data about intakes of proteins and amino acids, fatty acids, carbohydrates, cholesterol, fibers, minerals, vitamins, and polyphenols. Estimates of the antioxidant activity of foods and of the dietetic protein load were also calculated. The diet of CD patients was poorer in fibers, polyphenols, vitamin A, beta-carotene, and fatty acids, and richer in animal proteins, vitamin B12, and niacin. PRAL was higher in CD patients’ diets, while ORAC was higher in HS. No significant differences were observed in carbohydrate and other macro- and micronutrient consumptions. CD dietary habits seem to reflect the so-called Western diet, possibly involved in CD pathogenesis. Furthermore, analysis of dietary habits allows for prevention of nutritional deficiencies and timely correction through education and supplementation.  相似文献   
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