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991.
AIMS: This study was undertaken to evaluate the association between cigarette smoking behavior and DSM-IV nicotine dependence. DESIGN: Drawing on a sample of first year college students selected for representation across a continuum of smoking behavior, current DSM-IV nicotine dependence criteria were assessed among participants reporting any smoking in the preceding week on a web-based survey protocol. Logistic regression and receiver operator characteristic analyses were used to estimate the overall concordance between smoking and DSM-IV nicotine dependence. FINDINGS: Relationships were supported between both quantity and frequency of smoking in the past week and DSM-IV nicotine dependence showing higher prevalence of dependence at higher levels of use (p<0.05). While the highest prevalence of nicotine dependence was seen among those reporting the most frequent and heavy smoking, a substantial number of participants reporting daily and/or heavy smoking did not meet criteria for nicotine dependence. Conversely, nicotine dependence was seen among a subgroup of participants reporting relatively low levels of non-daily smoking. Diagnostic concordance was found to be moderate for both quantity and frequency and was not improved by combining information from these two indices. CONCLUSIONS: Aside from confirming DSM-IV nicotine dependence at relatively low levels of smoking, these results may be used to inform research aimed at identifying samples of nicotine dependent youth across the range of smoking levels.  相似文献   
992.
PURPOSE: Anaphylaxis is a life-threatening condition; drug-related anaphylaxis represents approximately 10% of all cases. We assessed the utility of a statewide emergency department (ED) database for identifying drug-related anaphylaxis in children by developing and validating an algorithm composed of ICD-9-CM codes. METHODS: There were 1 314,760 visits to South Carolina (SC) emergency departments (EDs) for patients <19 years in 2000-2002. We used ICD-9-CM disease or external cause of injury codes (E-codes) that suggested drug-related anaphylaxis or a severe drug-related allergic reaction. We found 50 cases classifiable as probable or possible drug-related anaphylaxis and 13 as drug-related allergic reactions. We used clinical evaluation by two pediatricians as the 'alloyed gold standard'1 for estimating sensitivity, specificity, and positive predictive value (PPV) of our algorithm. RESULTS: ED-treated drug-related anaphylaxis in the SC pediatric population was 1.56/100,000 person-years based on the algorithm and 0.50/100,000 person-years based on clinical evaluation. Assuming the disease codes we used identified all potential anaphylaxis cases in the database, the sensitivity was 1.00 (95%CI: 0.79, 1.00), specificity was 0.28 (95%CI: 0.16, 0.43), and the PPV was 0.32 (0.20, 0.47) for the algorithm. Sensitivity analyses improved the measurement properties of the algorithm. CONCLUSIONS: E-codes were invaluable for developing an anaphylaxis algorithm although the frequently used code of E947.9 was often incorrectly applied. We believe that our algorithm may have over-ascertained drug-related anaphylaxis patients seen in an ED, but the clinical evaluation may have under-represented this diagnosis due to limited information on the offending agent in the abstracted ED records. Post-marketing drug surveillance using ED records may be viable if clinicians were to document drug-related anaphylaxis in the charts so that billing codes could be assigned properly.  相似文献   
993.
Selective CB2 receptor agonists are promising potential therapeutic agents for the treatment of inflammatory and neuropathic pain. A focused screen identified a pyrimidine ester as a partial agonist at the CB2 receptor with micromolar potency. Subsequent lead optimization identified 35, GW842166X, as the optimal compound in the series. 35 has an oral ED50 of 0.1 mg/kg in the rat FCA model of inflammatory pain and was selected as a clinical candidate for this indication.  相似文献   
994.
Thymomas are the most common tumours of the anterior mediastinum, with most cases presenting incidentally. We present a case of extensive pleural thymoma initially thought to be unresectable, which was treated with neoadjuvant chemotherapy and pleuro pneumonectomy. We discuss the multimodality approach to management of this tumour, in particular the use of neoadjuvant chemotherapy prior to surgical resection.  相似文献   
995.
OBJECTIVE: This research evaluated a brief mailed intervention for alcohol use as an adjunct to a brief treatment for college students with depression symptoms. The intervention aimed to correct normative misperceptions and reduce students' drinking and related consequences. METHOD: One hundred seventy seven college students (70% Female) with elevated scores on the Beck Depression Inventory were randomly assigned to intervention or control group. Participants in the intervention were mailed feedback and information detailing their reported alcohol use, moderation strategies, and accurate normative information regarding student drinking. RESULTS: Results indicated no main effects of the intervention on drinking or related problems but students receiving feedback showed significant reductions in their perception of drinking norms compared to the control group. Furthermore, students whose normative perceptions reduced showed significant reductions in total drinks per week and total alcohol related problems compared to those whose norms did not reduce. CONCLUSIONS: Results support the importance of correcting normative perceptions and provide direction for selective prevention of alcohol use and related problems among college students with depressed mood.  相似文献   
996.
Previous research has evaluated marijuana motives among adolescents and emerging adults using a predetermined set of motives, largely adapted from the alcohol literature. This research was designed to identify marijuana motives from the perspective of the user. Recent high school graduates who reported using marijuana (N=634) provided self-generated reasons for using. The most frequently reported reasons included enjoyment/fun, conformity, experimentation, social enhancement, boredom, and relaxation. Regression analyses revealed that experimentation was consistently associated with less use and fewer problems whereas enjoyment, habit, activity enhancement, and altered perception or perspectives were associated with heavier use and more problems.  相似文献   
997.
The unique drinking patterns of college students call for Event-Specific Prevention (ESP) strategies that address college student drinking associated with peak times and events. Despite limited research evaluating ESP, many college campuses are currently implementing programming for specific events. The present paper provides a review of existing literature related to ESP and offers practical guidance for research and practice. The prevention typology proposed by DeJong and Langford [DeJong, W. & Langford, L. M. (2002). A typology for campus-based alcohol prevention: Moving toward environmental management strategies. Journal of Studies on Alcohol, 140-147.] provides a framework for strategic planning, suggesting that programs and policies should address problems at the individual, group, institution, community, state, and society level, and that these interventions should focus on knowledge change, environmental change, health protection, and intervention and treatment services. From this typology, specific examples are provided for comprehensive program planning related to orientation/beginning of school year, homecoming, 21st birthday celebrations, spring break, and graduation. In addition, the University of Connecticut's efforts to address problems resulting from its annual Spring Weekend are described as an illustration of how advance planning by campus and community partners can produce a successful ESP effort.  相似文献   
998.
To study the affect of mechanical stimuli on human laryngeal fibroblasts, we developed bioreactors capable of vibrating cell seeded substrates at frequencies and displacements comparable to measured phonation values in human subjects. In addition, we developed a means of harvesting the secreted matrix as a bulk biomaterial by removing the polymer foam using an organic solvent. Using the system human derived laryngeal fibroblasts were subjected to vibrational stimuli (100 Hz) for 1-21 days. Following mechanical conditioning, extracellular matrix and matrix related gene expression, cytokine production, matrix protein accumulation, and construct material properties were assessed with DNA microarray, enzyme linked immunosorbent, indirect immunofluorescent, and uni-axial tensile assays respectively. The results show that vocal fold-like vibrational stimuli is sufficient to influence the expression of several key matrix and matrix related genes, enhance the secretion of the profibrotic cytokine TGFbeta1, increase the accumulation of the extracellular matrix proteins, fibronectin and collagen type 1, as well as enhance construct stiffness compared to non-stimulated controls. Our results demonstrate that high frequency substrate vibration, like cyclic strain, can accelerate matrix deposition from human derived laryngeal fibroblasts. The study supports the notion that preconditioning regimens using human cells may be useful for producing cell derived biomaterials for therapeutic application.  相似文献   
999.
Brucella strains produce abortion and infertility in their natural hosts and a zoonotic disease in humans known as undulant fever. These bacteria do not produce classical virulence factors, and their capacity to successfully survive and replicate within a variety of host cells underlies their pathogenicity. Extensive replication of the brucellae in placental trophoblasts is associated with reproductive tract pathology in natural hosts, and prolonged persistence in macrophages leads to the chronic infections that are a hallmark of brucellosis in both natural hosts and humans. This review describes how Brucella strains have efficiently adapted to their intracellular lifestyle in the host.  相似文献   
1000.
Steep action potential duration (APD) restitution has been shown to facilitate wavebreak and ventricular fibrillation. The global APD restitution properties in cardiac patients are unknown. We report a combined clinical electrophysiology and computer modelling study to: (1) determine global APD restitution properties in cardiac patients; and (2) examine the interaction of the observed APD restitution with known arrhythmia mechanisms. In 14 patients aged 52-85 years undergoing routine cardiac surgery, 256 electrode epicardial mapping was performed. Activation-recovery intervals (ARI; a surrogate for APD) were recorded over the entire ventricular surface. Mono-exponential restitution curves were constructed for each electrode site using a standard S1-S2 pacing protocol. The median maximum restitution slope was 0.91, with 27% of all electrode sites with slopes<0.5, 29% between 0.5 and 1.0, and 20% between 1.0 and 1.5. Eleven per cent of restitution curves maintained slope>1 over a range of diastolic intervals of at least 30 ms; and 0.3% for at least 50 ms. Activation-recovery interval restitution was spatially heterogeneous, showing regional organization with multiple discrete areas of steep and shallow slope. We used a simplified computer model of 2-D cardiac tissue to investigate how heterogeneous APD restitution can influence vulnerability to, and stability of re-entry. Our model showed that heterogeneity of restitution can act as a potent arrhythmogenic substrate, as well as influencing the stability of re-entrant arrhythmias. Global epicardial mapping in humans showed that APD restitution slopes were organized into regions of shallow and steep slopes. This heterogeneous organization of restitution may provide a substrate for arrhythmia.  相似文献   
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