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941.
OBJECTIVES: To determine whether ethnicity was associated with baseline and 18-month health status within a merged sample of older adults with knee osteoarthritis (OA) from the Fitness Arthritis in Seniors Trial and the Arthritis, Diet, and Activity Promotion Trial. DESIGN: Cross-sectional and prospective study. SETTING: Center-based exercise therapy at two universities. PARTICIPANTS: A total of 584 African-American (n=143) and Caucasian-American (n=441) adults aged 60 and older with knee OA were examined for baseline and 18-month health status. MEASUREMENTS: Six-minute-walk distance, 36-item Short Form General Health Scale (SF-36 GHS), and Physical Functioning Questionnaire index score. Ethnicity was obtained via self-report. RESULTS: Analyses of covariance testing the effect of ethnicity, adjusted for demographic and health status covariates, revealed significant effects for ethnicity upon baseline 6-minute-walk distance and SF-36 GHS, with Caucasian Americans reporting better scores (P=.001), although these differences were not significant after 18 months of exercise therapy. CONCLUSION: Ethnicity and baseline function are important factors that should not be overlooked in knee OA research involving exercise interventions. Moreover, not only should physical activity be recommended to improve functional outcomes, it may also be a useful strategy in reducing health disparities.  相似文献   
942.
This article examines the effect of convictions for domestic violence or a related charge on the recidivism of batterers. Findings indicate that convictions reduce the likelihood of domestic violence recidivism. The variance explained by the conviction variable is modest; however, conviction remains significant when the batterers' histories of domestic violence charges and other background variables are introduced. The article also explores the associations between batterers' background characteristics and court convictions, as well as the effect of sanctions on the recidivism of convicted batterers.  相似文献   
943.
944.
945.
Evidence for sensory prediction deficits in schizophrenia   总被引:5,自引:0,他引:5  
OBJECTIVE: Patients with schizophrenia experiencing delusions and hallucinations can misattribute their own actions to an external source. The authors test the hypothesis that patients with schizophrenia have defects in their ability to predict the sensory consequences of their actions. METHOD: The authors measured sensory attenuation of self-produced stimuli by patients with schizophrenia and by healthy subjects. RESULTS: Patients with schizophrenia demonstrated significantly less sensory attenuation than healthy subjects. CONCLUSIONS: Patients with a diagnosis of schizophrenia have a dysfunction in their predictive mechanisms.  相似文献   
946.
OBJECT: The ability to map cerebrovascular reactivity (CVR) at the tissue level in patients with moyamoya disease could have considerable impact on patient management, especially in guiding surgical intervention and assessing the effectiveness of surgical revascularization. This paper introduces a new noninvasive magnetic resonance (MR) imaging-based method to map CVR. Preoperative and postoperative results are reported in three cases to demonstrate the efficacy of this technique in assessing vascular reserve at the microvascular level. METHODS: Three patients with angiographically confirmed moyamoya disease were evaluated before and after surgical revascularization. Measurements of CVR were obtained by rapidly manipulating end-tidal PCO2 between hypercapnic and hypocapnic states during MR imaging. The CVR maps were then calculated by comparing the percentage of changes in MR signal with changes in end-tidal PCO2. Presurgical CVR maps showed distinct regions of positive and negative reactivity that correlated precisely with the vascular territories supplied by severely narrowed vessels. Postsurgical reactivity maps demonstrated improvement in the two patients with positive clinical outcome and no change in the patient in whom a failed superficial temporal artery-middle cerebral artery bypass was performed. CONCLUSIONS: Magnetic imaging-based CVR mapping during rapid manipulation of end-tidal PCO2 is an exciting new method for determining the location and extent of abnormal vascular reactivity secondary to proximal large-vessel stenoses in moyamoya disease. Although the study group is small, there seems to be considerable potential for guiding preoperative decisions and monitoring efficacy of surgical revascularization.  相似文献   
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948.
OBJECTIVE: This open-label, prospective, observational, Post-Marketing Surveillance (PMS) study assessed the efficacy and safety of donepezil in patients who had been switched from therapies currently used in Germany to treat Alzheimer's disease (AD), such as memantine and nootropics, due to insufficient efficacy or poor tolerability. A treatment-naive population was included as a comparator. RESEARCH DESIGN AND METHODS: Patients with AD were treated with donepezil and observed for a period of approximately 3 months. A cognitive assessment was made using the Mini-Mental State Examination (MMSE). Quality of life (QoL) was assessed by the investigators who answered the question 'How did therapy with donepezil influence the QoL of the patient and/or his family over the observation period?' and was graded using three ratings: improved/unchanged/worsened. Adverse events (AEs) were also monitored. RESULTS: A total of 913 patients entered the study (mean +/- SD MMSE score 18.03 +/- 5.34). Efficacy assessments were analyzed for three groups: an overall group of patients who had received any form of prior AD drug therapy (N+ group; n = 709); a subgroup of patients from the N+ group who had received prior memantine therapy only (M+ group; n = 111) and patients who were drug treatment naive (N- group; n = 204). In the evaluable population donepezil improved MMSE scores by 2.21 +/- 3.47 points on average, with similar improvements observed in all three groups. QoL was judged to be improved in at least 70% of patients, again with similar results obtained for all three groups. Donepezil was well tolerated, with 85 of 913 (9.3%) patients reporting AEs. The most common AEs were those typically seen with cholinergic therapies (i.e., diarrhoea, vomiting and nausea). CONCLUSIONS: In this observational PMS study, donepezil was shown to be efficacious and well tolerated in patients who were being insufficiently treated with memantine or nootropic therapy. The magnitude of response was similar to that observed in patients who were previously treatment naive, suggesting prior medication does not effect donepezil's efficacy.  相似文献   
949.
Benzodiazepine poisoning causes coma and respiratory depression. Our objective was to determine whether, and to what extent, arterial blood gas disturbances correlated with blood or cerebral kinetics of midazolam. A 160 mgkg(-1) single dose of midazolam was infused intravenously over 20 min in catheterized male Sprague-Dawley rats. Midazolam kinetics was simultaneously determined in plasma and brain using striatal microdialysis. Midazolam concentrations were measured using a high-performance liquid chromatographic assay with ultraviolet detection. Midazolam (160 mgkg(-1)) reproducibly induced deep coma with respiratory acidosis. Plasma midazolam kinetics was well described by a bi-exponential model, with an elimination half-life of 6.4+/-1.8 h. The striatal dialysate concentration peaked at 50.0+/-8.9 min after the end of infusion, with a significant delay to peak concentration compared to plasma. Respiratory depression, assessed by the elevation in PaCO2, was more closely correlated with midazolam striatal dialysate rather than plasma kinetics. These results suggest a central mechanism for midazolam respiratory effects at toxic doses in rats. In conclusion, our study showed a delayed onset in peak PaCO2 and pH effects after the slow infusion of a toxic dose of midazolam in rats. The effects on arterial blood gases were better correlated with midazolam striatal concentrations than with plasma concentrations. This study may contribute to better understanding of benzodiazepine-induced respiratory depression in poisonings.  相似文献   
950.
BACKGROUND: Subliminal presentation of visual abandonment cues leads to greater levels of eating, despite a lack of conscious awareness of the information involved. The current study examined whether this behavioral impact can be countered by the subliminal presentation of contradictory, counterschematic information (unification cues). METHOD: Ninety-six nonclinical women were presented with subliminal abandonment cues, either preceded or followed by neutral or unification cues. The dependent variable was the amount eaten after the task. RESULTS: Presenting subliminal unification information before or after the subliminal abandonment cue significantly reduced the amount eaten (relative to the impact of neutral cues). DISCUSSION: These findings are consistent with a model where preconscious processing of unification cues has the effect deactivating abandonment schemas, either through inoculation or restoration. Preconscious presentation of unification cues might play a role in the broader cognitive-behavioral treatment of bulimic behaviors.  相似文献   
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