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11.
Purpose Reduced cement film thicknesses can improve crown seating and decrease marginal discrepancies. Improved marginal adaptation has the potential to reduce plaque accumulation, periodontal disease, and cement dissolution. Studies have indicated that dynamic seating methods can reduce seating discrepancies associated with zinc phosphate and resin cements. However, other types of cements and other dynamic techniques have not yet been studied or compared, nor has the mechanism for improved seating been fully explained. Therefore, the purpose of this study was to investigate the effect of a variety of loading methods on the film thicknesses of current types of crown and fixed partial denture cements compressed between glass plates. Materials and Methods This study investigated the effect of three dynamic loading methods on film thickness of six representative fixed prosthodontic cements. These included zinc phosphate, resin-modified glass ionomer, encapsulated glass ionomer, adhesive composite resin, composite resin, and polycarboxylate. The method was derived from American Dental Association specifications for cement film thickness. In control groups, the cements were placed between two glass plates and statically loaded with a 15-kg weight. The test groups were initially similarly loaded, and then for 30 seconds further subjected to simulated repeated patient opening and closing, vibrations from an electromallet, or an ultrasonic device. Results Mean film thicknesses ranged from 7.4 μm for polycarboxylate/ultrasound up to 40.3 μm for composite resin/static. Two-way analysis of variance revealed that the effects of material type and cementation method and their interaction all significantly affected film thickness (P < .0001). Multiple range analysis showed that dynamic methods were generally superior to static loading and that the ultrasonic method was the best overall. Conclusions The different dynamic loading methods all significantly decreased cement film thicknesses between glass plates. The ultrasonic method was the most effective. The type of cement used also influenced film thickness. Composite resins were more affected than other materials.  相似文献   
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AIMS: To evaluate short-term patient compliance with 5 conservative temporomandibular disorder (TMD) treatments (jaw relaxation, jaw stretching, heat application, cold application, and occlusal splint use) and the association of compliance with changes in pain intensity, pain-related activity interference, and jaw use limitations. METHODS: Eighty-one TMD patients were given 1 to 5 treatment recommendations as part of usual care in a TMD specialty clinic. Compliance with each recommendation and pain, pain-related activity interference, and jaw use limitation measures were calculated from electronic interviews conducted 3 times daily for 2 weeks. RESULTS: Median compliance with individual treatment modalities ranged from 7.7% for heat application to 92.7% for jaw relaxation; median overall compliance was 54.8%. Participants with higher initial pain intensity and jaw use limitations were significantly more compliant with their recommended treatment regimen (P < .05). The authors controlled for age, gender, education, and initial jaw use limitations. Overall compliance was associated significantly and positively with 2-week jaw use limitations (P = .03). A trend toward a statistically significant positive association was found between compliance and 2-week pain intensity (P = .09). CONCLUSION: Compliance varied widely across patients and therapies. Patients with higher initial pain and jaw use limitation levels were more compliant with treatment recommendations. Although compliance was associated with slight increases in pain and jaw use limitations in this preliminary study, further research is needed to evaluate the longer-term effects of compliance with recommended therapies.  相似文献   
13.
OBJECTIVES: The purpose of this study was (i) to assess the coping strategies of 11-year-old children when dealing with pain at the dentist, (ii) to determine the extent to which the level of the children's dental fear and their experience with pain at the dentist are related to their ability to cope and their choice of strategies, and (iii) to analyse the possible differences between subsamples concerning dental caries. METHODS: The coping strategies were investigated using the Dental Cope Questionnaire (n = 597); the level of dental fear was assessed using the Children's Fear Survey Schedule (CFSS-DS); a question is asked whether a child had experienced pain at the dentist in the past and dental caries was assessed using the DMFS index. RESULTS: The results show that 11-year olds use a variety of coping strategies. Internal strategies are used most frequently, external coping strategies are used less frequently, and destructive strategies are hardly used. The subjects rate internal and external strategies as effective. Children with pain experience and fearful children use more coping strategies, with fearful children using more internal strategies. Reported pain and anxiety were related to the dental status. CONCLUSIONS: The use and choice of coping strategies seems to be at least partly determined by the level of dental fear and the child's experience with pain.  相似文献   
14.
BACKGROUND: The purpose of this study was to review the literature on the effects of a mouthrinse containing essential oils (EO) on plaque and parameters of gingival inflammation. METHODS: The MEDLINE and Cochrane Central Register of Controlled Trials were searched up to and including December 2006 to identify appropriate studies. The primary outcome measure was gingivitis. Secondary parameters were plaque and, when reported, staining. RESULTS: Independent screening of titles and abstracts of 566 papers resulted in 11 publications that met the criteria of eligibility. In all studies, EO was used as an adjunct to regular daily toothbrushing. A statistically significant reduction in overall gingivitis was noted compared to the control (weighted mean difference [WMD]: -0.32, 95% confidence interval [CI]: -0.46 to -0.19, P <0.00001; test for heterogeneity: P <0.00001, I(2) = 96.7%). For interproximal sites the use of the test mouthrinse resulted in significantly more gingivitis reduction compared to control mouthrinse (WMD: -0.29, 95% CI: -0.48 to -0.11, P = 0.002; test for heterogeneity: P <0.00001, I(2) = 95.18%), whereas no differences were observed compared to dental floss. With respect to plaque scores, EO produced significant overall reductions in plaque (WMD: -0.83, 95% CI: -1.13 to -0.53, P <0.00001; test for heterogeneity: P <0.00001, I(2) = 96.1%). Separate analysis for interproximal areas revealed that EO resulted in more pronounced plaque drops compared to the control mouthrinse (WMD: -1.02, 95% CI: -1.44 to -0.60, P <0.00001; test for heterogeneity: P <0.00001, I(2) = 96.1%) or the use of floss (WMD: -0.75, 95% CI: -1.15 to -0.363, P <0.0002; test for heterogeneity: P <0.0002, I(2) = 93.0%). Most studies agreed that EO did not produce more staining than the control products. CONCLUSION: When used as an adjunct to unsupervised oral hygiene, EO provides an additional benefit with regard to plaque and gingivitis reduction as compared to a placebo or control.  相似文献   
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16.
Abstract -  Objectives: To develop a standardized method for measuring the variables affecting fluoride ingestion from toothpaste in young children between the ages of 1.5 and 3.5 years, and to use the method at seven European sites. Methods: Random samples of children were invited to take part in the study. Parents who gave consent were visited at home. The children brushed their teeth using the toothpaste brand and toothbrush type currently in use. Variables measured were: type of toothpaste used, fluoride concentration of toothpaste used, weight of toothpaste used, frequency of brushing and body weight of the child. Results: It was not possible to follow the agreed protocol in all seven countries and in three countries appropriate alternative methods were employed. There was considerable variation between countries in the variables investigated. Use of children's toothpaste ranged from 69% in Ireland to 98% in Portugal. In the Netherlands up to 60% of the children were using toothpaste containing <400 ppm F and in Finland up to 27% of children were using toothpaste containing >1200 ppm F. Over half of the children used <0.25 g of toothpaste per brushing and the majority of children brushed once or twice per day. Conclusion: Although adherence to the agreed protocol was not possible at all study sites there was a clear picture of considerable variation in the oral hygiene practices of young children throughout Europe.  相似文献   
17.
Abstract -  Objectives: The aim of this study was to collate data on national policies for the use of fluoride in the seven European countries participating in the FLINT project. Methods: Policies on the use of fluoride were obtained for each of the study areas. Data collected included the presence of water fluoridation and regulations governing fluoride toothpaste and fluoride supplements. Results: In Ireland 74% of the population had a fluoridated water supply but in all the other countries fluoride toothpaste was the principal form of delivering fluoride, usually recommended as a dose of a pea-sized amount. Fluoride supplement use varied considerably between countries. The Netherlands had the clearest regulations covering the use of fluoride supplements and definition of at-risk individuals. Most countries, even if they recognized particular caries-risk did not define the term clearly. In Iceland all children were regarded as being at high risk of developing caries. Conclusion: Considerable variation exists between European countries in their policies for fluoride use and no clear definitions of high-caries-risk individuals were found. The results show that there is even a lack of coherent thought and planning within the different countries, let alone between them.  相似文献   
18.
Issues in Financing Dental Care for the Elderly   总被引:1,自引:0,他引:1  
The elderly make up an increasingly larger segment of the patient population in dental practices. This article reviews recent epidemiologic, demographic, and health services research, and concludes that significant segments of the elderly are at high risk for oral disease and/or limited access to dental treatment, and consequently warrant classification as high-risk groups for policy considerations. It then proposes policy options to the dental community and public decision makers. Oral care can be viewed as having three components. Two basic components are the primary care component--which includes diagnostic, preventive restorative, and periodontal care--and the acute care component--i.e., the treatment of oral pain, trauma, and infection. The third, rehabilitative component, has to do with the restoration of oral function, including prosthodontics and cosmetic dentistry. Viewing dental care in this perspective may help link funding for dental primary care services with that for other primary health services, and link restoration of function and improvement of quality of life with similar health services, like hearing, vision, and social services. In addition, approaching dental care policy makers on several levels--i.e., federal, state, and local--will contribute to our ability as a profession, in the decades ahead, to meet the oral health needs of more elders: including the frail, those at high risk for oral disease, and those with limited access to care.  相似文献   
19.
The baseline caries experienced of approximately 5,000 children in South Carolina and Maine was used as the dependent variable in caries risk assessment analyses. Clinical, microbiologic, and demographic factors served as independent variables in a multivariate relationship to caries through regression and discriminant function analyses. Four factors--number of dental visits by the child in the past year, presence of white spot lesions, and both the urgency of need for restorative care and the future caries increment predicted by the examiner--associated significantly and consistently with caries prevalence in primary and permanent teeth of first and fifth graders at both study sites. Several factors associated significantly with caries prevalence at only one site or grade within a site, suggesting that wide applicability of a specific caries risk assessment model may be limited. In these analyses, sensitivity ranged from .60 to .72 and specificity varied from .86 to .91 in the four grade-site groups. The ultimate goal of this longitudinal study is to identify highly caries-prone children in time to prevent the occurrence of a future caries increment. Although the lack of consistent association of many variables, including microbiologic factors, with baseline caries prevalence was unexpected, it is expected that some of these variables will contribute predictive power in the prospective study.  相似文献   
20.
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