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41.
42.
The study evaluated a multifaceted educational intervention systematically designed to increase physician involvement in cholesterol-lowering practices. We hypothesized that knowledge, perceptions and behaviours would be enhanced in participating physicians, compared with controls. Method: Fifty-one family physicians were assigned randomly to three groups; the two experimental groups attended a training workshop, received physician and patient education materials and ongoing consultant support. One experimental group also received a “cuing” intervention. The control group received no interventions. Outcome measures included knowledge and attitude scores, self-efficacy perceptions, and physician dietary counselling behaviour. Measures were taken at pretest, 6 weeks and 15 months later. Results: Intervention group physicians achieved significantly higher knowledge scores than the control group at the six-week test; the differences disappeared at 15 months. Attitudes, self-reported practices and overall self-efficacy scores were similar across groups. Within group variation was highly significant. Physician dietary counselling scores were significantly higher in the intervention groups (p = 0.0001). Some associations were seen among knowledge, attitude, self-efficacy and dietary counselling scores. Conclusion: Physician behaviour change in cholesterol reduction may not depend entirely upon knowledge, attitudes and perceptions. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
43.
  • ? Nursing practice is based on experience, tradition, intuition, common sense, untested theory and sometimes research.
  • ? There are a number of reasons why nurses may see research as irrelevant to their practice.
  • ? This paper provides a model identifying possible strategies to help nurses develop research-based practice.
  相似文献   
44.
Quinidine and verapamil are widely used as antiarrhythmic agents and their combination is often used in the treatment of supraventricular tachycardia. This study was undertaken to clarify, whether these drugs exert proarrhythmic effects on the ventricles in therapeutic concentrations and whether possible arrhythmogenic effects might be enhanced by combination. Isolated rabbit hearts perfused according to the Langendorff technique were treated with increasing concentrations of quinidine (0.05 to 3.5 M) or verapamil (5 to 50 M) or of their combination (70:1 or 10:1; quinidine:verapamil) corresponding to common low, medium and high free therapeutic concentrations. The epicardial activation process was measured using a computer assisted mapping system for unipolar multichannel recording (256 channels simultaneously).Both substances prolonged the atrioventricular conduction time PQ. This effect was even more pronounced if the 70:1 combination was administered. The activation pattern was altered by both drugs and their combination to the same extent as became obvious from analysis of local activation vectors and of localisation of breakthroughpoints of epicardial activation for heart beats under control conditions and under drug treatment. The epicardial potential durations were prolonged by quinidine and to the same degree by the combinations, but not by verapamil alone. The total activation time was prolonged under the influence of quinidine and if the 70:1 combination was given. Both substances exerted a negative inotropic effect which was enhanced in an additive manner if both drugs were combined. In parallel the coronary flow was diminished.From these results it is concluded that (1) in this therapeutic concentration range quinidine possess a greater proarrhythmic risk than verapamil, (2) that both drugs' PQ prolonging effect can be enhanced by combination, (3) that combination does not enhance the proarrhythmic effects but the negative inotropic effects.  相似文献   
45.
Summary The recognition of recurring sites of chromosome changes in malignancies has greatly facilitated the identification of genes implicated in the pathogenesis of human cancers. Based especially upon recent studies [1–4], it appears increasingly likely that a subset of recurring chromosome alterations will be recognized in human breast cancer. Currently recognized chromosome changes characterizing breast carcinoma include the recognition of cytologic features of gene amplification (e.g. double minutes [dmins] and homogeneously staining regions [HSRs]) [5–8]. As these and other chromosome regions are implicated in recurring abnormalities in breast cancer, it will become increasingly important to have band-or region-specific genomic libraries and probes in order to facilitate high resolution physical mapping and ultimately to clone breast cancer related genes [9]. Toward this end an important recent development in physical mapping has been the establishment of chromosome microdissection as a rapid and reproducible approach to rapidly isolate and characterize chromosome region-specific DNA, greatly facilitating the initial steps in positional cloning of disease-related genes [10–13]. In this brief report, we will highlight the application of chromosome microdissection to the generation of region-specific probes for both fluorescent in situ hybridization (FISH) and the generation of genomic microclone libraries. Additionally, efforts using this methodology to generate a microclone library encompassing the early onset breast/ovarian cancer (BRCA1) gene will be presented.Presented by Jeffrey M. Trent at the 16th Annual San Antonio Breast Cancer Symposium, San Antonio TX, USA, November 4, 1993; Minisymposium on Molecular Genetics in Breast Cancer.  相似文献   
46.
47.
In binding assays, both dynorphin B and alpha-neoendorphin are relatively selective for the kappa1b site, unlike U50,488H which has high affinity for both kappa1a and kappa1b sites. In vivo, U50,488H, dynorphin B and alpha-neoendorphin analgesia are reversed by the kappa1-selective antagonist, nor-binaltorphimine (norBNI). Antisense mapping the three exons of KOR-1 revealed that probes targeting all three exons blocked U50,488H analgesia, as expected. However, the selectivity profile of dynorphin B and alpha-neoendorphin analgesia towards the various antisense oligodeoxynucleotides differed markedly from U50,488H, implying a different receptor mechanism of action.  相似文献   
48.
Community-based public health projects have become increasinglyimportant as a tool for health promotion. This approach hasbeen considered appropriate also in addressing socio-economicdifferences in health, although little is known about socio-economicdifferences in perception of health as a community issue. Ouraim was to study socio-economic differences in awareness andknowledge about the Kirseberg Project and in attitudes towardsthe concept of health as a local community issue. The KirsebergProject was initiated in 1988. The primary prevention aims areto reduce alcohol consumption in the population in order todecrease the incidence of alcohol-related problems. Kirsebergis an area with 10000 inhabitants in the north-eastern partof the city of Malmö (population 230000), Sweden. A sampleof 400 people in the area between the ages of 20 and 75 yearsof age was randomised from the population register and interviewedby telephone. Of the sample, 73.3% responded. Of the respondents,65.2% were aware of the project and 38.6% had knowledge aboutit. Socio-economic differences were found both regarding knowledgeand attitudes. Individuals in the high socio-economic status(SES)-group were better informed about the project than thelow SES-group, more often associated the project with the promotionof the community spirit, tended to give more positive answersto the questions about important local health issues, demonstratedhigher adherence to the social environment issues and were moreinterested in local health promotion activities. Our conclusionis that the socio-economic knowledge differences which werefound in the Kirseberg Project should be seen as shortcomingsin the health educational campaign rather than as a first stepin a determined social process. The issue of how the explicitnotions and the hidden agenda of a health promotion campaigncorrespond with central attitudes and values in different populationgroups in the target community must be carefully investigated.  相似文献   
49.
This study identifies brain regions participating in the execution of eye movements for voluntary positive accommodation (VPA) during open-loop vergence conditions. Neuronal activity was estimated by measurement of changes in regional cerebral blood flow (rCBF) with positron emission tomography and 15O-water. Thirteen naive volunteers viewed a checkerboard pattern with their dominant right eye, while a lens interrupted the line of gaze during alternate 1.5 s intervals. Three counterbalanced tasks required central fixation and viewing of a stationary checkerboard pattern: (i) through a 0.0 diopter (D) lens; (ii) through a -5.0-D lens while avoiding volitional accommodation and permitting blur; and (iii) through a -5. 0-D lens while maintaining maximal focus. The latter required large-amplitude, high-frequency VPA. As an additional control, seven of the subjects viewed passively a digitally blurred checkerboard through a 0.0-D lens as above. Optometric measurements confirmed normal visual acuity and ability to perform the focusing task (VPA). Large-amplitude saccadic eye movements, verified absent by electro-oculography, were inhibited by central fixation. Image averaging across subjects demonstrated multifocal changes in rCBF during VPA: striate and extrastriate visual cortices; superior temporal cortices; and cerebellar cortex and vermis. Decreases in rCBF occurred in the lateral intraparietal area, prefrontal and frontal and/or supplementary eye fields. Analysis of regions of interest in the visual cortex showed systematic and appropriate task dependence of rCBF. Activations may reflect sensorimotor processing along the reflex arc of the accommodation system, while deactivations may indicate inhibition of systems participating in visual search.  相似文献   
50.
The Human Genome Project will have an enormous impact on our ability to study and understand human disease by providing maps of human genes. However, many of the most prevalent human diseases result from the complex interaction of numerous genes. Even with the use of a catalogue of human genes, the task of analyzing complex genetic and environmental interactions involved in the common human disorders will be formidable. Due to its demographic specificities and large size, the Chinese population offers a unique resource for the study of human genetics and the ability to capitalize upon the recent revolution in biotechnology. Reasons that China provides an exceptional population for genetic studies of complex diseases include: (i) the resource of 1.3 billion people makes obtaining a large number of subjects with rare (and common) diseases possible; (ii) relative genetic homogeneity in many regions has been preserved; (iii) stratification is distinct; (iv) urban/rural and geograph ic contrasts, both in environmental factors and disease occurrence, are quite marked; (v) family members tend to stay congregated; and (vi) epidemiologic study is cost-beneficial.  相似文献   
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