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981.
BNP (B-type natriuretic peptide) has been reported to be elevated in preclinical states of vascular damage. To elucidate the relationship between plasma BNP and endothelial function, we have investigated the relationship between BNP and endothelial function in a cohort of subjects comprising healthy subjects as well as at-risk subjects with cardiovascular risk factors. To also clarify the relative contribution of different biological pathways to the individual variation in endothelial function, we have examined the relationship between a panel of multiple biomarkers and endothelial function. A total of 70 subjects were studied (mean age, 58.1±4.6?years; 27% had a history of hypertension and 18% had a history of hypercholesterolaemia). Endothelium-dependent vasodilatation was evaluated by the invasive ACH (acetylcholine)-induced forearm vasodilatation technique. A panel of biomarkers of biological pathways was measured: BNP, haemostatic factors PAI-1 (plasminogen-activator inhibitor 1) and tPA (tissue plasminogen activator), inflammatory markers, including cytokines [hs-CRP (high sensitive C-reactive protein), IL (interleukin)-6, IL-8, IL-18, TNFα (tumour necrosis factor α) and MPO (myeloperoxidase] and soluble adhesion molecules [E-selectin and sCD40 (soluble CD40)]. The median BNP level in the study population was 26.9 pg/ml. Multivariate regression analyses show that age, the total cholesterol/HDL (high-density lipoprotein) ratio, glucose and BNP were independent predictors of endothelial function, and BNP remained an independent predictor (P=0.009) in a binary logistic regression analysis using FBF (forearm blood flow) as a dichotomous variable based on the median value. None of the other plasma biomarkers was independently related to ACH-mediated vasodilatation. In a strategy using several biomarkers to relate to endothelial function, plasma BNP was found to be an independent predictor of endothelial function as assessed by endothelium-dependent vasodilatation in response to ACH.  相似文献   
982.
Fetal cardiac function has been shown to be a marker of disease severity in many conditions, including intrauterine growth restriction, congenital heart defects or disease (CHD), twin-to-twin transfusion syndrome, idiopathic hydrops, fetal arrhythmias, and others. It is often targeted for evaluation of patient management, for providing complete and accurate diagnoses in CHD, for patient counseling, or in referring for fetal cardiac interventions. In this review we will describe the use of M-mode and 4D spatiotemporal image correlation in fetal cardiac evaluation, the parameters that can be measured, and their application to clinical practice.  相似文献   
983.
984.

Background

Serbia has proclaimed access to healthcare as a human right. In a context wherein the Roma population are disadvantaged, the aim of this study was to assess whether the Roma population are able to effectively access primary care services, and if not, what barriers prevent them from doing so. The history of the Roma in Serbia is described in detail so as to provide a context for their current vulnerable position.

Methods

Disaggregated data were analyzed from three population groups in Serbia; the general population, the Roma population, and the poorest quintile of the general population not including the Roma. The effective coverage framework, which incorporates availability, affordability, accessibility, acceptability, and effectiveness of health services, was used to structure the secondary data analysis. Acute respiratory infection (ARI) in children less than five years of age was used as an example as this is the leading cause of death in children under 5 years old in Serbia.

Results

Roma children were significantly more likely to experience an ARI than either the general population or the poorest quintile of the general population, not including the Roma. All three population groups were equally likely to not receive the correct treatment regime of antibiotics. An analysis of the factors that affect quality of access to health services reveal that personal documentation is a statistically significant problem; availability of health services is not an issue that disproportionately affects the Roma; however the geographical accessibility and affordability are substantive issues that disproportionately affect the Roma population. Affordability of services affected the Roma and the poorest quintile and affordability of medications significantly affected all three population groups. With regards to acceptability, mothers from all three population groups are equally likely to recognize the importance of seeking treatment.

Conclusions

The Roma should be assisted in applying for personal documentation, the geographical accessibility of clinics needs to be addressed, and the costs of healthcare visits and medications should be reviewed. Areas for improvement specific to ARI are the costs of antibiotics and the diagnostic accuracy of providers. A range of policy recommendations are outlined.  相似文献   
985.
986.
The development of critical consciousness is seen as a key stage in communities increasing levels of dialogue about priority problems and effecting structural change for health. However, relatively little research identifies concrete methods for programmes to build critical consciousness. We examined how a South African structural intervention used critical consciousness as a tool for prevention of intimate partner violence and HIV infection. We collected qualitative data in the form of in-depth interviews with managers, trainers, and participants of the Intervention with Microfinance for AIDS and Gender Equity intervention (IMAGE) in rural South Africa. The data were analysed through a coding structure developed in QSR NVivo. We draw practical lessons from IMAGE to guide other HIV programmes aiming to promoting critical consciousness and social mobilization. This research suggests that specific curricular tools can work towards critical consciousness and that mobilization efforts in future programmes can be strengthened by including individual and collective efforts by participants.  相似文献   
987.
988.

Objective

To examine the factor structure of the Missoula Vitas Quality of Life Index (MVQOLI) in palliative care patients in South Africa and Uganda and to assess the tool’s appropriateness for measuring quality of life (QOL) in this context.

Study Design and Setting

Cross-sectional survey using the MVQOLI, a 26-item QOL measure containing five subscales (Function, Symptoms, Interpersonal, Well being, and Transcendent), in five palliative care services in South Africa and Uganda.

Results

Two hundred eighty-five patients were recruited; mean age was 40.1 years; 197 (69.1%) were female; primary diagnoses were human immunodeficiency virus infection (80.7%) and cancer (17.9%). A five-factor solution, accounting for 55% of variance, presented the best model of fit. The factors corresponded relatively closely to the original subscales, with only 4 of the 20 items not loading on the factor corresponding to the appropriate subscale. Internal consistency was high (α = 0.83).

Conclusion

We found evidence of five factors underpinning the MVQOLI in a large sample of South African and Ugandan palliative care patients. The five factors corresponded reasonably well to the original subscales, suggesting that it is a promising measure for use in this population. However, further testing of its psychometric properties, comprehensibility, and scoring require further research in sub-Saharan Africa.  相似文献   
989.
We studied the neural correlates of rapid eye movement during sleep (REM) by timing REMs from video recording and using rapid event-related functional MRI. Consistent with the hypothesis that REMs share the brain systems and mechanisms with waking eye movements and are visually-targeted saccades, we found REM-locked activation in the primary visual cortex, thalamic reticular nucleus (TRN), 'visual claustrum', retrosplenial cortex (RSC, only on the right hemisphere), fusiform gyrus, anterior cingulate cortex, and the oculomotor circuit that controls awake saccadic eye movements (and subserves awake visuospatial attention). Unexpectedly, robust activation also occurred in non-visual sensory cortices, motor cortex, language areas, and the ascending reticular activating system, including basal forebrain, the major source of cholinergic input to the entire cortex. REM-associated activation of these areas, especially non-visual primary sensory cortices, TRN and claustrum, parallels findings from waking studies on the interactions between multiple sensory data, and their 'binding' into a unified percept, suggesting that these mechanisms are also shared in waking and dreaming and that the sharing goes beyond the expected visual scanning mechanisms. Surprisingly, REMs were associated with a decrease in signal in specific periventricular subregions, matching the distribution of the serotonergic supraependymal plexus. REMs might serve as a useful task-free probe into major brain systems for functional brain imaging.  相似文献   
990.
Driving while intoxicated remains a major public health hazard. Driving is a complex task involving simultaneous recruitment of multiple cognitive functions. The investigators studied the neural substrates of driving and their response to different blood alcohol concentrations (BACs), using functional magnetic resonance imaging (fMRI) and a virtual reality driving simulator. We used independent component analysis (ICA) to isolate spatially independent and temporally correlated driving-related brain circuits in 40 healthy, adult moderate social drinkers. Each subject received three individualized, separate single-blind doses of beverage alcohol to produce BACs of 0.05% (moderate), 0.10% (high), or 0% (placebo). 3 T fMRI scanning and continuous behavioral measurement occurred during simulated driving. Brain function was assessed and compared using both ICA and a conventional general linear model (GLM) analysis. ICA results replicated and significantly extended our previous 1.5T study (Calhoun et al. [2004a]: Neuropsychopharmacology 29:2097-2017). GLM analysis revealed significant dose-related functional differences, complementing ICA data. Driving behaviors including opposite white line crossings and mean speed independently demonstrated significant dose-dependent changes. Behavior-based factors also predicted a frontal-basal-temporal circuit to be functionally impaired with alcohol dosage across baseline scaled, good versus poorly performing drivers. We report neural correlates of driving behavior and found dose-related spatio-temporal disruptions in critical driving-associated regions including the superior, middle and orbito frontal gyri, anterior cingulate, primary/supplementary motor areas, basal ganglia, and cerebellum. Overall, results suggest that alcohol (especially at high doses) causes significant impairment of both driving behavior and brain functionality related to motor planning and control, goal directedness, error monitoring, and memory.  相似文献   
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