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21.
Vaping of synthetic cannabinoids via e‐cigarettes is growing in popularity. In the present study, we tentatively identified 12 by‐products found in a pure sample of the synthetic cannabinoid Cumyl‐5F‐PINACA (1‐(5‐fluoropentyl)‐N‐(2‐phenylpropan‐2‐yl)‐1H‐indazole‐3‐carboxamide), a prevalent new psychoactive substance (NPS) in e‐liquids, via high‐resolution mass spectrometry fragmentation experiments (HRMS/MS). Furthermore, we developed a procedure to reproducibly extract this synthetic cannabinoid and related by‐products from an e‐liquid matrix via chloroform and water. The extracts were submitted to flash chromatography (F‐LC) to isolate the by‐products from the main component. The chromatographic impurity signature was subsequently assessed by ultra‐high‐performance liquid chromatography coupled to mass spectrometry (UHPLC–MS) and evaluated by automated integration. The complete sample preparation sequence (F‐LC + UHPLC–MS) was validated by comparing the semi‐quantitative signal integrals of the chromatographic impurity signatures of five self‐made e‐liquids with varying concentrations of Cumyl‐5F‐PINACA [0.1, 0.2, 0.5, 0.7 and 1.0% (w/w)], giving an average relative standard deviation of 6.2% for triplicate measurements of preparations of the same concentration and 10.5% between the measurements of the five preparations with different concentrations. Lastly, the chromatographic signatures of 14 e‐liquid samples containing Cumyl‐5F‐PINACA from police seizures and Internet test purchases were evaluated via hierarchical cluster analysis for potential links. For the e‐liquid samples originating from test purchases, it was found that the date of purchase, the identity of the online shop, and the brand name are the critical factors for clustering of samples.  相似文献   
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Background

We examined the association of cognitive vulnerability to depression with changes in homogeneous measures of depressive symptoms.

Methods

Baseline and 1-year follow-up data were obtained from 2981 participants of the Netherlands study of depression and anxiety. Multivariate regression analyses were carried out on cognitive reactivity, locus of control and implicit and explicit self-depressive associations in combination with negative life events. The purpose of this analysis was to predict changes on the mood/cognition and anxiety/arousal subscales of the inventory of depressive symptomatology - self report.

Results

Cognitive reactivity, locus of control and explicit self-depressive associations were independently associated with changes in depressive symptoms after adjustment for covariates and baseline severity (all p<0.01). Negative life-events interacted with cognitive vulnerability to depression to predict depressive symptoms. Locus of control (b1=0.16, SE=0.02, η2=0.01; b2=0.10, SE=0.02, η2=0.004, F=8.69, p<0.01) and explicit self-depressive associations (b1=0.10, SE=0.03, η2=0.02; b2=0.02, SE=0.04, F=7.50, p<0.01) were more strongly associated with the cognitive (b1) than the somatic (b2) symptom dimension of depression.

Limitations

The study sample is over-inclusive of depressed patients. Therefore it might be problematic generalizing the findings to the general population.

Conclusion

Cognitive etiological factors may play a role in a “cognitive” subtype of depression. The findings strengthen the notion that homogeneous measures of depressive symptoms enable a greater degree of discrimination between subtypes than a multidimensional conception of depression.  相似文献   
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The advent of massive parallel sequencing is rapidly changing the strategies employed for the genetic diagnosis and research of rare diseases that involve a large number of genes. So far it is not clear whether these approaches perform significantly better than conventional single gene testing as requested by clinicians. The current yield of this traditional diagnostic approach depends on a complex of factors that include gene‐specific phenotype traits, and the relative frequency of the involvement of specific genes. To gauge the impact of the paradigm shift that is occurring in molecular diagnostics, we assessed traditional Sanger‐based sequencing (in 2011) and exome sequencing followed by targeted bioinformatics analysis (in 2012) for five different conditions that are highly heterogeneous, and for which our center provides molecular diagnosis. We find that exome sequencing has a much higher diagnostic yield than Sanger sequencing for deafness, blindness, mitochondrial disease, and movement disorders. For microsatellite‐stable colorectal cancer, this was low under both strategies. Even if all genes that could have been ordered by physicians had been tested, the larger number of genes captured by the exome would still have led to a clearly superior diagnostic yield at a fraction of the cost.  相似文献   
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BackgroundThe randomized SOLVE-TAVI (compariSon of secOnd-generation seLf-expandable vs. balloon-expandable Valves and gEneral vs. local anesthesia in Transcatheter Aortic Valve Implantation) trial compared newer-generation self-expanding valves (SEV) and balloon-expandable valves (BEV) as well as local anesthesia with conscious sedation (CS) and general anesthesia (GA) in patients undergoing transfemoral transcatheter aortic valve replacement (TAVR). Both strategies showed similar outcomes at 30 days.ObjectivesThe purpose of this study was to compare clinical outcomes during 1-year follow-up in the randomized SOLVE-TAVI trial.MethodsUsing a 2 × 2 factorial design 447 intermediate- to high-risk patients with severe, symptomatic aortic stenosis were randomly assigned to transfemoral TAVR using either the SEV (Evolut R, Medtronic Inc., Minneapolis, Minnesota) or the BEV (Sapien 3, Edwards Lifesciences, Irvine, California) as well as CS or GA at 7 sites.ResultsIn the valve-comparison strategy, rates of the combined endpoint of all-cause mortality, stroke, moderate or severe paravalvular leakage, and permanent pacemaker implantation were similar between the BEV and SEV group (n = 84, 38.3% vs. n = 87, 40.4%; hazard ratio: 0.94; 95% confidence interval: 0.70 to 1.26; p = 0.66) at 1 year. Regarding the anesthesia comparison, the combined endpoint of all-cause mortality, stroke, myocardial infarction, and acute kidney injury occurred with similar rates in the GA and CS groups (n = 61, 25.7% vs. n = 54, 23.8%; hazard ratio: 1.09; 95% confidence interval: 0.76 to 1.57; p = 0.63).ConclusionsIn intermediate- to high-risk patients undergoing transfemoral TAVR, newer-generation SEV and BEV as well as CS and GA showed similar clinical outcomes at 1 year using a combined clinical endpoint. (SecOnd-generation seLf-expandable Versus Balloon-expandable Valves and gEneral Versus Local Anesthesia in TAVI [SOLVE-TAVI]; NCT02737150)  相似文献   
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Ligands of the endothelial-enriched tunica interna endothelial cell kinase 2 (Tie2) are markedly imbalanced in severe infections associated with vascular leakage, yet regulation of the receptor itself has been understudied in this context. Here, we show that TIE2 gene expression may constitute a novel vascular barrier control mechanism in diverse infections. Tie2 expression declined rapidly in wide-ranging models of leak-associated infections, including anthrax, influenza, malaria, and sepsis. Forced Tie2 suppression sufficed to attenuate barrier function and sensitize endothelium to permeability mediators. Rapid reduction of pulmonary Tie2 in otherwise healthy animals attenuated downstream kinase signaling to the barrier effector vascular endothelial (VE)-cadherin and induced vascular leakage. Compared with wild-type littermates, mice possessing one allele of Tie2 suffered more severe vascular leakage and higher mortality in two different sepsis models. Common genetic variants that influence TIE2 expression were then sought in the HapMap3 cohort. Remarkably, each of the three strongest predicted cis-acting SNPs in HapMap3 was also associated with the risk of acute respiratory distress syndrome (ARDS) in an intensive care unit cohort of 1,614 subjects. The haplotype associated with the highest TIE2 expression conferred a 28% reduction in the risk of ARDS independent of other major clinical variables, including disease severity. In contrast, the most common haplotype was associated with both the lowest TIE2 expression and 31% higher ARDS risk. Together, the results implicate common genetic variation at the TIE2 locus as a determinant of vascular leak-related clinical outcomes from common infections, suggesting new tools to identify individuals at unusual risk for deleterious complications of infection.Among vascular-enriched receptor tyrosine kinases, Tie2 is unusual in at least two functional aspects. First, Tie2 phosphorylation is tightly controlled by the interplay of several proteins: a paralogous receptor, Tie1; a tyrosine phosphatase, vascular endothelial-protein tyrosine phosphatase (VE-PTP); and two secreted ligands, angiopoietin (Angpt)-1 and Angpt-2, the latter of which can act as an agonist, partial agonist, or antagonist depending upon context (16). Second, unlike classic growth factor receptors, Tie2 is heavily expressed and phosphorylated throughout the quiescent adult vasculature (7), suggesting that Tie2 signaling has one or more roles in vascular maintenance.Based largely on Angpt-1 overexpression studies, Tie2 has been implicated in vascular barrier defense (8, 9). However, adult-specific deletion of Angpt-1 does not appear to trigger vascular leakage (10). Moreover, Angpt-1 has repeatedly been ascribed functions that are independent of Tie2 (1113). Finally, observational studies in humans suffering clinical manifestations of vascular leakage have consistently shown a marked imbalance in Tie2 ligands tilting in favor of Angpt-2 (reviewed in 14). Although decreased Tie2 activity has been inferred from these reports, the role of TIE2 gene expression has not been directly queried experimentally or in clinical settings.This question is important not only for understanding control mechanisms of the circulatory system but also to guide the development of strategies to predict, stratify, and treat patients affected by acute vascular leakage. If tonic Tie2 signaling is indeed necessary for vascular barrier maintenance, then reducing the pool of receptors could constitute a ligand-independent means to attenuate barrier-protective signaling in the endothelium. We therefore hypothesized that the level of Tie2 expression modulates the sensitivity of blood vessels, and thereby the entire organism, to noxious stimuli. Cellular, rodent, and human genetics studies were undertaken to test this concept.  相似文献   
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Cytomegalovirus (CMV) infection is common among infants of HIV-infected mothers in resource-limited settings. We examined the prevalence and timing of infant CMV infection during the first year of life using IgG antibody and avidity among HIV-exposed infants in Malawi and correlated the results with the presence of detectable CMV DNA in the blood. The Breastfeeding, Antiretrovirals and Nutrition (BAN) study randomized 2,369 mothers and their infants to maternal antiretrovirals, infant nevirapine, or neither for 28 weeks of breastfeeding, followed by weaning. Stored plasma specimens were tested for CMV IgG and antibody avidity from a random subset of infants who had been previously tested with blood CMV PCR and had available specimens at birth and at 24 and 48 weeks of age. Ninety-four of 127 infants (74.0%) tested at 24 weeks of age had CMV IgG of low or intermediate avidity, signifying primary CMV infections. An additional 22 infants (17.3%) had IgG of high avidity; 19 of them had CMV DNA detected in their blood, indicating infant infections. Taken together, these results show that the estimated prevalence of CMV infection at 24 weeks was 88.9%. By 48 weeks of age, 81.3% of infants had anti-CMV IgG; most of them (70.9%) had IgG of high avidity. The CMV serology and avidity testing, combined with the PCR results, confirmed a high rate of primary CMV infection by 6 months of life among breastfeeding infants of HIV-infected mothers. The CMV PCR in blood detected most, but not all, infant CMV infections.  相似文献   
29.
Nephrolithiasis is a less common side effect of the antiepileptic drug topiramate. We report the case of a 3‐year‐old boy who presented to the emergency department with abdominal pain; examinations revealed a large calcification in the left kidney. Regular ultrasound examinations are recommended in children using topiramate.  相似文献   
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