全文获取类型
收费全文 | 3817篇 |
免费 | 364篇 |
国内免费 | 31篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 93篇 |
妇产科学 | 52篇 |
基础医学 | 296篇 |
口腔科学 | 42篇 |
临床医学 | 580篇 |
内科学 | 610篇 |
皮肤病学 | 23篇 |
神经病学 | 214篇 |
特种医学 | 86篇 |
外科学 | 142篇 |
综合类 | 358篇 |
预防医学 | 1241篇 |
眼科学 | 17篇 |
药学 | 227篇 |
1篇 | |
中国医学 | 79篇 |
肿瘤学 | 136篇 |
出版年
2024年 | 6篇 |
2023年 | 103篇 |
2022年 | 145篇 |
2021年 | 336篇 |
2020年 | 254篇 |
2019年 | 231篇 |
2018年 | 210篇 |
2017年 | 163篇 |
2016年 | 145篇 |
2015年 | 141篇 |
2014年 | 248篇 |
2013年 | 286篇 |
2012年 | 218篇 |
2011年 | 253篇 |
2010年 | 175篇 |
2009年 | 193篇 |
2008年 | 169篇 |
2007年 | 175篇 |
2006年 | 130篇 |
2005年 | 90篇 |
2004年 | 70篇 |
2003年 | 57篇 |
2002年 | 66篇 |
2001年 | 53篇 |
2000年 | 41篇 |
1999年 | 36篇 |
1998年 | 31篇 |
1997年 | 23篇 |
1996年 | 24篇 |
1995年 | 21篇 |
1994年 | 19篇 |
1993年 | 11篇 |
1992年 | 13篇 |
1991年 | 12篇 |
1990年 | 10篇 |
1989年 | 9篇 |
1988年 | 8篇 |
1987年 | 9篇 |
1986年 | 5篇 |
1985年 | 4篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 1篇 |
排序方式: 共有4212条查询结果,搜索用时 417 毫秒
1.
《Journal of the Academy of Nutrition and Dietetics》2022,122(11):2060-2071
BackgroundVoices for Food was a longitudinal community, food pantry–based intervention informed by the social ecological model, and designed to improve food security, dietary intake, and quality among clients, which was carried out in 24 rural food pantries across 6 Midwestern states.ObjectiveOur objective was to evaluate changes in adult food security, dietary intake, and quality from baseline (2014) to follow-up (2016), and to assess the role of adult food security on dietary outcomes.DesignA multistate, longitudinal, quasi-experimental intervention with matched treatment and comparison design was used to evaluate treatment vs comparison group changes over time and changes in both groups over time.Participants/settingAdult food pantry clients (n = 617) completed a demographic food security survey, and up to three 24-hour dietary recalls at baseline (n = 590) and follow-up (n = 160).InterventionCommunity coaching served as the experimental component, which only “treatment” communities received, and a food council guide and food pantry toolkit were provided to both “treatment” and matched “comparison” communities.Main outcome measuresChange in adult food security status, mean usual intakes of nutrients and food groups, and Healthy Eating Index-2010 scores were the main outcome measures.Statistical analyses performedLinear mixed models estimated changes in outcomes by intervention group and by adult food security status over time.ResultsImprovements in adult food security score (–0.7 ± 0.3; P = .01), Healthy Eating Index-2010 total score (4.2 ± 1.1; P < .0001), and empty calories component score (3.4 ± 0.5; P <.0001) from baseline to follow-up were observed in treatment and comparison groups, but no statistically significant changes were found for adult food security status, dietary quality, and usual intakes of nutrients and food groups between the 2 groups over time. The intervention effect on dietary quality and usual intake changes over time by adult food security status were also not observed.ConclusionsFood pantry clients in treatment and comparison groups had higher food security and dietary quality at the follow-up evaluation of the Voices for Food intervention trial compared with baseline, despite the lack of difference among the groups as a result of the experimental coaching component. 相似文献
2.
3.
4.
《Health & place》2019
The objective of this paper was to assess the link between premature mortality and a combination of neighbourhood contextual (environmental and health) and compositional (socioeconomic and demographic) characteristics. We statistically and spatially examined six environmental variables (ultrafine particles, carcinogenic and non-carcinogenic pollutants, pollution released to air, tree cover, and walkability index), six health service indicators (number health providers, breast, colorectal and cervical cancer screening uptake rates, student nutrition program uptake rates, and healthy food index), and eight socioeconomic indicators (total income, Gini coefficient, two age categories – below and above 40 years, proportion of females to males, visible minorities, Indigenous peoples, education, less than grade 9) among 140 neighbourhoods of the City of Toronto in Ontario (Canada). We applied principal component analysis to identify patterns and to reduce the number of explanatory variables into combined component axes that represent unique variation in these confounded and overlapping factors. We then applied regression analysis to model the relationship between the indices of enviro-health and socioeconomics and their potential relationship with premature mortality. Residual spatial analysis was used to investigate any remaining spatial structure (such as neighbourhoods with higher residual premature mortality rates). Neighbourhood Equity Index was correlated with our enviro-health and socioeconomic indices. Premature mortality within neighbourhoods was predicted by poor cancer screenings, pollution, lack of tree canopy, increased uptake of student nutrition programs and high walkability index. A negative association between premature mortality and pollution was associated low walkability index and presence of visible minorities within neighbourhoods. There was some unexplained residual spatial variation in our model of premature mortality - especially along the shores of Lake Ontario and in neighbourhoods with major highways or road corridors: premature mortality in Toronto neighbourhoods was higher than expected along highway-corridor neighbourhoods and shorelines. Our analysis revealed a significant relationship between neighbourhood contextual features – both environmental and health – and premature mortality, suggesting that these contextual components of neighbourhoods can predict rates of urban premature mortality in Toronto. 相似文献
5.
《Gait & posture》2019
BackgroundStanding on textured materials can improve static balance, potentially by modulating somatosensory inputs from the soles of the feet.Research questionTo synthesise and quantify the immediate effects of textured materials on static balance in healthy young and older adults.MethodsPrimary outcomes were the centre of pressure (COP) displacement and velocity, during eyes open and eyes closed conditions. Ten crossover studies (n = 318, 58% female) met the inclusion criteria. A random effects meta-analysis model derived pooled standardised mean differences (SMD; Hedges g) to quantify the effects of textured materials. Heterogeneity was quantified with the tau-statistic (τ). A 95% prediction interval quantified the likely range of true effects on COP outcomes in similar future studies.ResultsThere was a small to moderate beneficial effect for textured materials vs control conditions in: COP displacement during both eyes open (SMD: 0.29; 95% CI -0.06 to 0.64; τ = 0.32) and eyes closed (SMD: 0.75; 95% CI 0.18 to 1.33; τ = 0.55). A trivial to small beneficial effect was observed in COP velocity during eyes open (SMD: 0.14; 95% CI -0.14 to 0.43; τ = 0.18) and eyes closed (SMD: 0.20; 95% CI 0.01 to 0.40; τ = 0.18) for textured materials. The 95% prediction intervals showed texture may not consistently provide beneficial results across studies for all outcomes: COP displacement EC (-0.61 to 2.12), EO (-0.54 to 1.12), COP velocity EC (-0.27 to 0.68) and EO (-0.44 to 0.73).SignificanceOverall, textured materials improved balance, but these effects were heterogeneous. This research may therefore inform applied investigations into balance improvements for healthy populations, for example, in functional movements and sports. 相似文献
6.
Jeannie K. Giese 《The Journal of asthma》2019,56(6):662-673
Objective: Asthma disproportionately impacts and has poorer outcomes in low-income, minority, and inner-city children. The home environment has a profound impact on a child's asthma. Home-based asthma visits have the potential to positively impact a child's asthma, especially in targeted populations. The purpose of this integrative review is 1.) to explore the effectiveness of home-based education and environmental measures and 2.) to explore specific indicators and tools to measure pediatric asthma control and program effectiveness. Data Sources: Medline, CINHAL, and Ovid databases were searched from 2010 to 2017 utilizing the keywords healthy homes AND asthma and home based interventions AND asthma. Study Selections: A total of 71 articles were retrieved of which 27 articles met the inclusion criteria of English language, human subjects, and the inclusion of pediatric populations. Three additional articles were hand-searched from previous references. In total, 30 articles were reviewed. A quality appraisal was conducted utilizing standardized appraisal tools. Results: Home-based asthma education and environmental interventions have proven to be effective. The programs reviewed varied in types of interventions, intensity and duration, the type of provider, length of follow-up, and outcome measures. Successful programs were patient-centered, included a home assessment and individualized education and interventions, and were collaborative. Multiple outcome indicators such as health care utilization, asthma control, missed days of school or productivity, asthma symptoms, and verification of environmental remediation have been utilized. Conclusion: Home-based asthma programs can be beneficial to children with poorly controlled asthma and have the potential to be cost-effective. 相似文献
7.
《Obesity research & clinical practice》2020,14(1):91-98
ObjectiveObesity has reached epidemic proportions in the US. Physical activity is an important component of obesity reduction, but little is known about contemporary exercise levels among overweight/obese American adults. In this study, we compared current physical activity levels in overweight and obese US adults to those of normal weight individuals as well as ascertained which sociodemographic factors influence the meeting of physical activity recommendations in these three groups.MethodsWe used national data from 2015 and 2017 Behavioral Risk Factor Surveillance System surveys (n = 726,075). Bivariate analyses were conducted to determine unadjusted physical activity levels in normal weight, overweight, and obese adults. We fit multinomial logistic models to identify associations between sociodemographic factors and meeting physical activity recommendations in our study population.ResultsAround 45% of overweight and 57% of obese adults failed to meet physical activity guidelines compared to 41% of normal weight adults. Age, sex, and race were significantly associated with physical activity levels for both overweight and obese adults. In overweight and obese individuals, associations between sociodemographic factors and physical activity were more similar between the two comparisons of insufficiently active (IA) versus active (A)/highly active (HA) and A versus HA but quite different to those in the inactive (IN) versus IA/A/HA comparison.ConclusionsFuture physical activity interventions should be aimed at increasing the number of overweight and obese US adults who meet physical activity guidelines as well as targeted towards specific sociodemographic groups within the overweight/obese population with low exercise levels. 相似文献
8.
目的:观察扶正化痰固本方运用于早期非小细胞肺癌术后的临床疗效及其对患者免疫功能的影响。方法:将70例早期非小细胞肺癌患者按照随机数字表法分为对照组和观察组,每组各35例。两组患者均接受肺癌切除术治疗,对照组术后3周开始接受MVP方案化疗,观察组在对照组的基础上加用扶正化痰固本方治疗。比较两组患者的临床疗效及治疗前后中医证候积分、卡氏评分(karnofsky performance status,KPS)及生活质量评分变化情况。检测两组患者治疗前后免疫功能指标、血清肿瘤标志物[癌胚抗原(carcinoembryonic antigen,CEA)、糖类抗原153(carbohydrate antigen 153,CA153)]水平。结果:观察组有效率为91.43%,对照组有效率为71.43%,两组患者有效率比较,差异具有统计学意义(P<0.05)。两组患者治疗后中医证候积分低于本组治疗前,且观察组治疗后低于对照组治疗后,差异具有统计学意义(P<0.05)。两组患者治疗后免疫功能指标检测结果低于本组治疗前,且观察组治疗后低于对照组治疗后,差异具有统计学意义(P<0.05)。两组患者治疗后血清CEA、CA153水平低于治疗前,KPS评分、QLQ-C30评分均高于治疗前,且观察组治疗后血清CEA、CA153水平低于对照组,KPS评分、QLQ-C30评分均高于对照组,差异具有统计学意义(P<0.05)。观察组胃肠道反应及骨髓抑制发生率均低于对照组,差异具有统计学意义(P<0.05)。结论:扶正化痰固本方运用于早期肺癌术后,能够有效改善患者免疫功能,减轻毒副反应,提高患者生活质量。 相似文献
9.
Principles and strategies of effective community participation 总被引:7,自引:5,他引:2
A framework is offered for understanding the conceptual basisand the strategic implications of community participation, inachieving Health for All goals. Special focus is given to themeaning, settings and levels of participation in official decision-makingstructures and at the community level. Questions such howis participation facilitated?, who participates?and what are the benefits and obstacles to participation?are geared primarily towards the needs of individuals who functionat the city level and expect practical strategic advice andguidance. The structure of the 1989 WHO Healthy Cities Symposiumwhich was devoted to community action was based on the frameworkand conceptual approach of this paper. 相似文献
10.
本文用气相色谱法对居住福州、长乐、宁化三个地区270名健康人群发铬含量进行调查。结果表明:福州地区发铬值高于其它两地区,并有非常显著性差异。总体发铬算术平均数与国内外部分地区所报导的结果比较接近,但在性别及年龄间差异不明显。对三个地区发铬值与当地土壤铬含量进行相关分析,r=0.9978,二者呈正相关,并有非常显著性意义。 相似文献