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911.
This study investigated the incidence of injury in sub-elite Rugby League players before and after the introduction of the limited interchange rule. The incidence of injury was prospectively studied in one sub-elite Rugby League club over three competitive seasons. Two seasons were played under the unlimited interchange rule, while the third season was played under the limited interchange rule. Players participated in 91 matches under the unlimited interchange rule and 44 matches under the limited interchange rule. Injury was defined as any pain, disability or injury that occurred as a result of a competition game that caused the player to miss a subsequent game. The relative risk (RR) of injury significantly decreased (RR = 0.70 [0.65 to 0.75], P<0.05) following the introduction of the limited interchange rule, with the incidence of injury decreasing from 72.5 (58.2 to 86.8) per 1000 playing hr under the unlimited interchange rule to 51.0 (33.8 to 68.1) per 1000 playing hr under the limited interchange rule. The risk of sustaining thigh and calf injuries (RR= 0.27 [0.12 to 0.59], P < 0.05), muscular strains (RR= 0.23 10.17 to 0.31]., P<0.05), and high intensity running injuries (RR= 0.16 [0.04 to 0.691, P<0.05) was significantly reduced following the introduction of the limited interchange rule. These findings demonstrate that the risk of injury in sub-elite Rugby League players is significantly reduced following the introduction of the limited interchange rule. The reduced injury risk may reflect a fatigue-induced reduction in match speed and impact forces associated with physical collisions and tackles.  相似文献   
912.

BACKGROUND AND PURPOSE

Cannabidiol (CBD) has emerged as an interesting compound with therapeutic potential in several CNS disorders. However, whether it can modulate synaptic activity in the CNS remains unclear. Here, we have investigated whether CBD modulates synaptic transmission in rat hippocampal cultures and acute slices.

EXPERIMENTAL APPROACH

The effect of CBD on synaptic transmission was examined in rat hippocampal cultures and acute slices using whole cell patch clamp and standard extracellular recordings respectively.

KEY RESULTS

Cannabidiol decreased synaptic activity in hippocampal cultures in a concentration-dependent and Pertussis toxin-sensitive manner. The effects of CBD in culture were significantly reduced in the presence of the cannabinoid receptor (CB1) inverse agonist, LY320135 but were unaffected by the 5-HT1A receptor antagonist, WAY100135. In hippocampal slices, CBD inhibited basal synaptic transmission, an effect that was abolished by the proposed CB1 receptor antagonist, AM251, in addition to LY320135 and WAY100135.

CONCLUSIONS AND IMPLICATIONS

Cannabidiol reduces synaptic transmission in hippocampal in vitro preparations and we propose a role for both 5-HT1A and CB1 receptors in these CBD-mediated effects. These data offer some mechanistic insights into the effects of CBD and emphasize that further investigations into the actions of CBD in the CNS are required in order to elucidate the full therapeutic potential of CBD.  相似文献   
913.

Introduction

Although Hispanics are a rapidly growing ethnic minority in the United States, the effect of acculturation on the proportion of Hispanics who meet national objectives for fruit and vegetable consumption has not been fully investigated. Our objective was to determine the extent to which ethnicity and acculturation (indicated by survey language preference) are associated with fruit and vegetable consumption among Hispanics in the United States.

Methods

Fruit and vegetable consumption among adult respondents to the 2009 Behavioral Risk Factor Surveillance System was determined from data collected from the 31 states and 2 territories that offered the fruit and vegetable screener in Spanish and English (n = 287,997). Logistic regression analyses were used to determine whether ethnicity (Hispanic vs non-Hispanic white) and survey language preference (English vs Spanish) were related to meeting objectives of consuming fruit 2 or more times per day and vegetables 3 or more times per day.

Results

More Hispanics (37.6%) than non-Hispanic whites (32.0%) and more Spanish-speaking Hispanics (41.0%) than English-speaking Hispanics (34.7%) ate fruit 2 or more times per day. Conversely, more non-Hispanic whites (28.5%) than Hispanics (18.9%) and more English-speaking Hispanics (21.8%) than Spanish-speaking Hispanics (15.8%) ate vegetables 3 or more times per day. All associations remained significant after controlling for covariates.

Conclusion

Our findings have implications regarding how brief screeners can be used to determine possible dietary disparities among the Hispanic population in the United States and to monitor population goals to eliminate racial and ethnic health disparities.  相似文献   
914.

Objective

Atherosclerosis is a chronic inflammatory process. Poly(ADP-ribose) polymerase-1 (PARP), a nuclear enzyme linked to DNA repair, has been shown to be involved in atherogenesis; however, the effects on dendritic cells, T cells and serum auto-antibody levels are not fully understood.

Methods

Male Apoe-/- mice on a western diet were treated with the PARP inhibitor 1NO-1001 (n = 15), while the control group (n = 15) received 5% glucose solution for 10 weeks.

Results

Inhibition of PARP markedly reduced atherosclerotic lesion development (p = 0.001). Immunohistochemistry and mRNA analysis revealed a reduced inflammatory compound inside the lesion. Focusing on dendritic cells, INO-1001 reduced number of cells (p = 0.04), grade of activation, represented by I/12 (p = 0.04) and Cd83 (p = 0.03), and grade of attraction, represented by Mip3α (p = 0.02) in the plaque. Furthermore, INO-1001 decreased number of T lymphocyte (p = 0.003) in the lesion and grade of activation after stimulation with oxLDL in vitro. Moreover, serum IgM antibody levels to oxLDL were significantly lower in INO-1001 treated mice (p = 0.03).

Conclusions

Functional blockade of PARP by INO-1001 reduces atherosclerotic lesion development. The anti-atherogenic effect is beside already known mechanisms also moderated due to modulation of DC and T cell invasion and activation, DC attraction as well as IgM antibody levels to oxLDL.  相似文献   
915.
Fifteen plant species were collected from the Nelspruit Botanical Garden based on a list of plants provided by Phytomedicine Programme at the University of Pretoria and their ethnopharmacological information. Hexane, dichloromethane (DCM), acetone and methanolic extracts were screened for antimycobacterial activity against Mycobacterium smegmatis. The acetone extract of Milletia stulhimannii was the most active, showing activity against Mycobacterium smegmatis with minimum inhibitory concentration (MIC) value of 0.13 mg/ml. Acetone extracts for all plants had lower MIC values ranging between 0.11–1.25 mg/ml against M. smegmatis. Milletia stulhimannii, Albizia gummifera, Xanthocercis zambesiaca and Barringtonia racemosa have shown great potential as anti-tuberculosis agents. They were active against M. smegmatis with average MIC values of acetone extracts of 0.13 mg/ml.  相似文献   
916.
917.
918.
Introduction: This study examines the feasibility of atrial fibrillation (AF) ablation using registered three-dimensional computed tomography (CT) images of the left atrium with fluoroscopy.
Methods and Results: A total of 50 consecutive patients with symptomatic AF refractory to medical therapy (32 paroxysmal, 18 persistent, age 55 ± 10 years) were randomized to undergo a catheter-based AF ablation procedure with or without the CT-fluoroscopy guidance system. All patients underwent preprocedural contrast-enhanced CT imaging and segmentation of the left atrium. For the CT-fluoroscopy group, circumferential lesions encompassing the pulmonary vein (PV) antrum and linear lesions along the roof of the left atrium between the superior PVs and the mitral isthmus were created on the CT image, which was registered with real-time fluoroscopy. The registered images were then used to navigate the ablation catheters to the sites of planned ablation. After the ablation sites were completed, any remaining PV potentials were isolated with electrophysiological guidance. In the control patients, the same technique was performed without using the CT-fluoro guidance system. CT scans were accurately registered to fluoroscopic images with minimal manual correction. Operators could navigate catheters on the registered images to preplanned, extraostial sites for ablation. CT-fluoroscopy guidance decreased procedure duration and fluoro times (P < 0.05). At a mean follow-up of 9 ± 2 months, 21 patients (84%) in the CT-fluoro guidance group and 16 patients (64%) in the control group have had no recurrence of AF.
Conclusion: CT-fluoroscopic-guided left atrial ablation is feasible and allows appropriate catheter manipulation in the left atrium.  相似文献   
919.
OBJECTIVE: To determine whether boys meeting diagnostic criteria for juvenile mania and attention deficit hyperactivity disorder (mania-ADHD) may be distinguished from boys with ADHD alone on a range of clinical and family variables. METHODOLOGY: Boys aged 9-13 years with mania-ADHD (n = 25), ADHD alone (n = 99), or no psychiatric diagnosis (n = 27) were compared on parent and teacher report Child Behavior Checklists (CBCL) and Conners Questionnaires, self-report CBCLs, patterns of comorbidity, intellectual functioning, and family variables. RESULTS: Mania-ADHD subjects had significantly higher mean ratings than ADHD only subjects on the parent CBCL for the Withdrawn, Thought Problems, Delinquent Behavior and Aggressive Behavior scales and significantly higher rates of comorbid depression, anxiety and psychotic symptoms. Other variables did not distinguish the mania-ADHD and ADHD only groups. CONCLUSIONS: These data confirm previous research indicating that the CBCL may be used to assist in the clinical identification of manic children.  相似文献   
920.
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