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991.
γ-Hydroxybutyrate (GHB) and its precursor γ-butyrolactone (GBL) are commonly abused drugs with a narrow therapeutic index. Therefore, overdoses occur readily with recreational use, and severe poisoning can occur after deliberate self-poisoning. We report the sequelae in a patient who ingested a massive dose of GBL, with suicidal intent. Severe metabolic acidosis and an asystolic cardiac arrest were successfully treated with standard resuscitation, supportive care, and continuous venovenous hemodiafiltration. Plasma GHB concentrations were the highest reported to date. The acidosis was attributed to rapid systemic absorption of GBL, followed by rapid metabolism to GHB.  相似文献   
992.
993.
Draft genome of the red harvester ant Pogonomyrmex barbatus   总被引:3,自引:0,他引:3  
We report the draft genome sequence of the red harvester ant, Pogonomyrmex barbatus. The genome was sequenced using 454 pyrosequencing, and the current assembly and annotation were completed in less than 1 y. Analyses of conserved gene groups (more than 1,200 manually annotated genes to date) suggest a high-quality assembly and annotation comparable to recently sequenced insect genomes using Sanger sequencing. The red harvester ant is a model for studying reproductive division of labor, phenotypic plasticity, and sociogenomics. Although the genome of P. barbatus is similar to other sequenced hymenopterans (Apis mellifera and Nasonia vitripennis) in GC content and compositional organization, and possesses a complete CpG methylation toolkit, its predicted genomic CpG content differs markedly from the other hymenopterans. Gene networks involved in generating key differences between the queen and worker castes (e.g., wings and ovaries) show signatures of increased methylation and suggest that ants and bees may have independently co-opted the same gene regulatory mechanisms for reproductive division of labor. Gene family expansions (e.g., 344 functional odorant receptors) and pseudogene accumulation in chemoreception and P450 genes compared with A. mellifera and N. vitripennis are consistent with major life-history changes during the adaptive radiation of Pogonomyrmex spp., perhaps in parallel with the development of the North American deserts.  相似文献   
994.
Objectives:We aimed to compare the quantitative angiographic aortic regurgitation (AR) into the left ventricular out flow tract (LVOT-AR) of five different types of transcatheter self-expanding valves and to investigate the impact of the learning curve on post-TAVR AR.Background:Quantitative video densitometric aortography is an objective, accurate, and reproducible tool for assessment of AR following TAVR.Methods and results:This retrospective academic core-lab analysis, analyzed 1150 consecutive cine aortograms performed immediately post-TAVR. Quantitative angiographic AR of post-procedural aortography in 181 consecutive patients, who underwent TAVR with the Venus A-valve in a single Chinese center, were compared to the results of Evolut Pro, Evolut R, CoreValve, (Medtronic, Dublin, Ireland) and Acurate Neo (Boston Scientific, Massachusetts, US) transcatheter heart valves (THVs), from a previously published pooled database. Among the 181 aortograms of patients treated with the Venus A-Valve, 113 (62.4%) were analyzable for quantitative assessment of AR. The mean LVOT-AR was 8.9% ± 10.0% with 14.2% of patients having moderate or severe AR in the Venus A-valve group. No significant difference in mean LVOT-AR was observed between Evolut Pro, Evolut R, Acurate Neo, and Venus A-valve. The incidence of LVOT-AR >17%, which correlates with echocardiographic derived ≥ moderate AR, with the Evolut Pro was lower than with the Venus A-valve (5.3% vs. 14.2%, p = 0.034), but was not different from the Evolut R (5.3% vs. 8.8%, p = 0.612), or the Acurate Neo (5.3% vs. 11.3% p = 0.16) systems. A landmark analysis after recruitment of the first half of patients treated with the Venus A valve (N = 56), showed a significantly lower mean LVOT-AR in the second half of the series (11.3% ± 11.9% vs. 6.5% ± 7.1%, p = 0.011). The incidence of LVOT-AR >17% in the latest 57 cases was also numerically lower (7.0% vs. 21.4%, p = 0.857) and compared favorably with the best in class of the self-expanding valves.ConclusionThe Venus A-valve has comparable mean LVOT-AR to other self-expanding valves but has a higher rate of moderate or severe AR than the Evolut Pro THV. However, after completion of a learning phase, results improved and compared favorably with the best in class of the commercially available self-expanding valves. These findings should be confirmed in prospective randomized comparisons of AR between different THVs.  相似文献   
995.
Although comorbid depression is a predictor of poor treatment response in obsessive-compulsive disorder (OCD), there is limited understanding of factors that contribute to depression severity in OCD. The current study examines the influence of OCD-related factors (autogenous obsessions and obsessional beliefs) and non-specific factors (avoidance and anxiety) on depression severity in a sample of OCD patients. There were 56 participants with only OCD and 46 with OCD and comorbid depression. Self-report questionnaires measuring depression, OCD-related factors, and non-specific factors were completed. Although there were no significant differences between the two groups on these variables, depression severity was positively correlated with anxiety, avoidance, obsessional beliefs, and autogenous obsessions in the whole sample. When entered into a multiple regression model to predict depression severity, these factors accounted for 51% of the variance. While OCD-related factors remained significant predictors after controlling for non-specific factors, the non-specific factors made the most significant contributions to the model. Our findings suggest that in addition to dealing with autogenous obsessions, addressing anxiety and avoidance might lead to improvements in the treatment of OCD with comorbid depression.  相似文献   
996.
Studies of supervised Categorization have demonstrated limited Categorization performance in participants with autism spectrum disorders (ASD), however little research has been conducted regarding unsupervised Categorization in this population. This study explored unsupervised Categorization using two stimulus sets that differed in their difficulty of Categorization according to the simplicity model. ASD participants displayed a greater tendency to categorise according to one dimension as compared with mental-aged matched participants in the easily categorised sets, but both ASD and Control groups became more prone to one-dimensional sorting as the difficulty of the Categorization task increased. These results are discussed in terms of the processes underlying over-selective responding.  相似文献   
997.
998.
ABSTRACT Background: Previous studies have shown that the presence of depressive symptoms among older persons was evidently associated with subsequent physical and functional decline. However, few studies have directly examined the impact of changes in depressive symptoms or depressed mood on changes in functional ability. The present prospective study examined whether changes in the levels and remission of depressive symptoms were associated with changes in functional ability among community-living older persons who were treated for depressive symptoms in a primary care setting. Methods: Older persons aged 60 and above with depressive symptoms (N = 267) were followed up in a primary care treatment program over 12 months. Geriatric Depression Scale (GDS-15), and instrumental and basic activities of daily living (IADL and ADL) were measured at baseline and at 12-month follow-up. The associations of GDS change scores and conversion to non-depressed status with ADL and IADL change scores, controlling for baseline covariates including chronic medical comorbidity and Mini-Mental State Examination (MMSE), were examined in multiple regression analyses. Results: An improvement in GDS scores (baseline score minus 12-month score) was significantly associated with improvement (12-month score minus baseline score) in ADL (β = 0.355, p < 0.001) and IADL scores (β = 0.165, p = 0.018) after adjusting for baseline functional status, MMSE, chronic medical comorbidities, and other variables. In particular, conversion in GDS status to "non-depressive" state (GDS ≤4) was associated with an improvement in ADL change scores (β = 0.281, p = 0.019). Conclusion: In depressed older persons, an improvement in depressive symptoms was associated with improved functional ability.  相似文献   
999.
OBJECTIVES:: To examine age- and sex-related differences in risk and protective factors for mild cognitive impairment (MCI) in community-based elderly individuals. DESIGN:: Cross-sectional study. SETTING:: The population-based Sydney Memory and Ageing Study. PARTICIPANTS:: A total of 757 nondemented, community-dwelling elderly individuals from an English-speaking background categorized as younger (70-79 years) or older (80-90 years). MEASUREMENTS:: Risk of MCI was determined for sociodemographic, lifestyle, and cardiac, physical, mental, and general health factors using age- (and sex-) adjusted multiple regressions comprising initially significant univariate factors. RESULTS:: The point prevalence of MCI within our sample was 39.1% overall: it was lowest in younger women (32.3%) and similar across men and older women (41.9%-43.6%). The risk of MCI across all participants was increased by the APOE ?4 allele, high homocysteine, and heart disease; and decreased by better odor identification, visual acuity, and mental activity. Risk factors in all younger participants were slow 6-m walk, poor odor identification, and high homocysteine. Risk of MCI was associated in younger women with history of depression, less mental activity, slower 6-m walk, poorer visual acuity, and higher homocysteine; and in younger men with poorer odor identification and higher homocysteine. Older participants showed no significant risk factors for MCI, except for poorer visual acuity in men. Supporting these findings were statistically significant interactions that reflected the differences in risk factor profiles between age and/or sex groups. CONCLUSIONS:: Risk factors for MCI differ in men and women and vary with age. This has implications for preventing MCI and possibly dementia.  相似文献   
1000.

Objective

We determined the utility of electrocorticography (ECoG) and stimulation for detecting language-related sites in patients with left-hemispheric language-dominance on Wada test.

Methods

We studied 13 epileptic patients who underwent language mapping using event-related gamma-oscillations on ECoG and stimulation via subdural electrodes. Sites showing significant gamma-augmentation during an auditory-naming task were defined as language-related ECoG sites. Sites at which stimulation resulted in auditory perceptual changes, failure to verbalize a correct answer, or sensorimotor symptoms involving the mouth were defined as language-related stimulation sites. We determined how frequently these methods revealed language-related sites in the superior-temporal, inferior-frontal, dorsolateral-premotor, and inferior-Rolandic regions.

Results

Language-related sites in the superior-temporal and inferior-frontal gyri were detected by ECoG more frequently than stimulation (p < 0.05), while those in the dorsolateral-premotor and inferior-Rolandic regions were detected by both methods equally. Stimulation of language-related ECoG sites, compared to the others, more frequently elicited language symptoms (p < 0.00001). One patient developed dysphasia requiring in-patient speech therapy following resection of the dorsolateral-premotor and inferior-Rolandic regions containing language-related ECoG sites not otherwise detected by stimulation.

Conclusions

Language-related gamma-oscillations may serve as an alternative biomarker of underlying language function in patients with left-hemispheric language-dominance.

Significance

Measurement of language-related gamma-oscillations is warranted in presurgical evaluation of epileptic patients.  相似文献   
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