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ObjectivesClinical trials have shown a beneficial effect from biological disease-modifying antirheumatic drugs (bDMARDs) on hand or axial bone loss in patients with rheumatoid arthritis; however, it is unclear if this translates to a reduced fracture risk. We investigated the effect of bDMARDs on osteoporotic fracture risk compared to no biological treatment in rheumatoid arthritis.MethodsA cohort of patients with rheumatoid arthritis aged 18+ from DANBIO was linked to population-based health registries in Denmark (2006-2016). Adopting a prevalent new-user design, we matched bDMARD users to bDMARD-naïve patients using time-conditional propensity scores. The risk of incident osteoporotic fractures (including hip, vertebrae, humerus, and forearm) was estimated among the matched patients by Cox proportional hazards models.ResultsOut of 24,678 patients with rheumatoid arthritis, 4265 bDMARD users were matched to the same number of bDMARD-naïve patients (mean age 56.2 years, 74% female). During follow-up, 229 osteoporotic fractures occurred among bDMARD users and 205 fractures among bDMARD-naïve patients (incidence rates 12.1 and 13.0 per 1000 person-years, respectively). The use of bDMARDs was not associated with a reduced risk of osteoporotic fractures among patients with rheumatoid arthritis (hazard ratio 0.97, 95% confidence interval 0.78-1.20), compared with no biological treatment. The risk estimates were similar for all osteoporotic fracture sites.ConclusionWe found no independent beneficial effect from using bDMARDs on reducing the risk of osteoporotic fractures in patients with rheumatoid arthritis.  相似文献   
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BackgroundDental caries is the most common chronic childhood disease. Past studies revealed that grandparents provide their grandchildren with cariogenic foods and beverages (eg, those with free sugars and/or modified starches). Qualitative research can help identify what drives this phenomenon.ObjectiveOur aim was to examine mothers’ explanations for why grandparents in north central and central Appalachia give their grandchildren cariogenic foods and beverages.DesignA qualitative study on children’s oral health in Pennsylvania and West Virginia from 2018 through 2020 was performed. In-person, semi-structured interviews were conducted. Qualitative data from interviews were recorded, transcribed, and then coded using NVivo. Data analysis for this study was performed using thematic analysis with iterative theme development.Participants/settingThe participants were 126 mothers of children aged 3-5 years from West Virginia (n = 66) and Pittsburgh, PA (n = 60).Main outcome measuresMothers’ perspectives about why grandparents give their grandchildren cariogenic foods and beverages were analyzed.ResultsIn the study sample, 85% of mothers (n = 107/126) named at least 1 of their children’s grandparents as a member of their social network responsible for their children’s oral health. From these interviews, 85% of mothers (n = 91/107) discussed that grandparents gave their grandchildren cariogenic foods and beverages. The mothers described the following 4 themes to explain why grandparents gave their grandchildren cariogenic foods and beverages: privilege of the grandparent role; responsibilities of the grandparent role; symbol of care and affection; and limited consideration or understanding of the detrimental impact.ConclusionsGrandparents play a role in giving their grandchildren cariogenic foods and beverages, which could potentially contribute to childhood caries. Research is needed to develop effective social interventions to help some grandparents understand the implications of a cariogenic diet on their grandchildren’s oral health and/or decrease their provision of cariogenic foods and beverages.  相似文献   
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PurposeTo evaluate the impact of concomitant use of conventional synthetic DMARDs (csCMARD) on adherence, switching and dose of biologic disease modifying antirheumatic drugs (bDMARD) in rheumatoid arthritis (RA) patients treated with bDMARDs.Patients and methodsThis was a population-based cohort study conducted in five provinces of Canada (Alberta, Manitoba, Ontario, Quebec, and Saskatchewan), and one American database (IBM® MarketScan® Databases). Adult RA patients entered the study after a 3-month initiation period of bDMARDs between 1 January 2007, and 30 March 2014. Concomitant csDMARD exposure was compared to non-csDMARD exposure on the following outcomes: discontinuation of bDMARD therapy, switching of bDMARDs, and percent change in dose of bDMARD compared to initial dose. The effect of the time-varying changes in csDMARD exposure was analyzed using marginal structural models. Dose change was analyzed using linear regression. Results from each participating site were combined using likelihood ratio meta-analysis.ResultsThe study population comprised 20,221 new users of bDMARDs: adalimumab (7609), etanercept (9809), abatacept (1024), infliximab (1779). Concomitant use of csDMARD therapy was not significantly associated with reduced discontinuation of bDMARD treatment (hazard ratio 0.90, 95% intrinsic confidence interval 0.79 to 1.02) or reduced switching of bDMARDs (hazard ratio 0.95, 95% intrinsic confidence interval 0.80 to 1.11), but was associated with a small increase in bDMARD dose compared to the mean dose over the first three months of treatment (mean percentage change in dose +0.56% mg/day, 95% intrinsic confidence interval +0.14% to +0.97%).ConclusionIn this large study of RA patients using bDMARDs in Canada and the United States, we found no clear evidence that patients who received concomitant csDMARD therapy were less likely to discontinue, switch or increase their dose of bDMARD.  相似文献   
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《Vaccine》2020,38(51):8185-8193
BackgroundWhile administration of the measles-mumps-rubella (MMR-II®) vaccine has been effective at preventing rubella infection in the United States, the durability of humoral immunity to the rubella component of MMR vaccine has not been widely studied among older adolescents and adults.MethodsIn this longitudinal study, we sought to assess the durability of rubella virus (RV)-specific humoral immunity in a healthy population (n = 98) of adolescents and young adults at two timepoints: ~7 and ~17 years after two doses of MMR-II® vaccination. Levels of circulating antibodies specific to RV were measured by ELISA and an immune-colorimetric neutralization assay. RV-specific memory B cell responses were also measured by ELISpot.ResultsRubella-specific IgG antibody titers, neutralizing antibody titers, and memory B cell responses declined with increasing time since vaccination; however, these decreases were relatively moderate. Memory B cell responses exhibited a greater decline in men compared to women.ConclusionsCollectively, rubella-specific humoral immunity declines following vaccination, although subjects’ antibody titers remain well above the currently recognized threshold for protective immunity. Clinical correlates of protection based on neutralizing antibody titer and memory B cell ELISpot response should be defined.  相似文献   
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A multitude of athletic injuries occur when the various tissues that make up the human body experience stresses and strains that exceed their material strength. The precise amount of stress and strain that any given tissue can withstand is determined by the mechanical properties and resultant strength of that particular tissue. These mechanical properties are directly determined by an individual’s physiology and acute regulation of these properties. A number of theoretical frameworks for athletic injury occurrence have been proposed, however, a detailed conceptual framework for injury aetiology that considers the interplay between the physiological and mechanical factors and outlines the causal pathways to tissue damage and injury is needed. This will guide injury research towards a more thorough investigation of causal mechanisms and understanding of risk factors. Further, it is important to take into account the considerable differences in loading patterns which can result in varying injury outcomes such as acute stress-related, strain-related, or overuse injury. Within this article a simplified conceptual model of athletic injury is proposed along with a detailed, evidence-informed, conceptual framework for athletic injury aetiology that focuses on stress-related, strain-related, and overuse injury.  相似文献   
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