全文获取类型
收费全文 | 489447篇 |
免费 | 37552篇 |
国内免费 | 11847篇 |
专业分类
耳鼻咽喉 | 6310篇 |
儿科学 | 13874篇 |
妇产科学 | 8084篇 |
基础医学 | 38007篇 |
口腔科学 | 12981篇 |
临床医学 | 54625篇 |
内科学 | 64332篇 |
皮肤病学 | 6152篇 |
神经病学 | 26396篇 |
特种医学 | 19154篇 |
外国民族医学 | 38篇 |
外科学 | 56270篇 |
综合类 | 63849篇 |
一般理论 | 42篇 |
预防医学 | 55542篇 |
眼科学 | 7006篇 |
药学 | 50030篇 |
604篇 | |
中国医学 | 34579篇 |
肿瘤学 | 20971篇 |
出版年
2023年 | 7454篇 |
2022年 | 12096篇 |
2021年 | 21667篇 |
2020年 | 19130篇 |
2019年 | 22347篇 |
2018年 | 17179篇 |
2017年 | 16414篇 |
2016年 | 16940篇 |
2015年 | 19107篇 |
2014年 | 36215篇 |
2013年 | 35582篇 |
2012年 | 35506篇 |
2011年 | 33467篇 |
2010年 | 29018篇 |
2009年 | 26861篇 |
2008年 | 24885篇 |
2007年 | 24977篇 |
2006年 | 21185篇 |
2005年 | 15856篇 |
2004年 | 11010篇 |
2003年 | 9617篇 |
2002年 | 7476篇 |
2001年 | 6246篇 |
2000年 | 5428篇 |
1999年 | 4121篇 |
1998年 | 3806篇 |
1997年 | 3425篇 |
1996年 | 2883篇 |
1995年 | 3020篇 |
1994年 | 2802篇 |
1993年 | 2313篇 |
1992年 | 2447篇 |
1991年 | 2179篇 |
1990年 | 2055篇 |
1989年 | 1959篇 |
1988年 | 1838篇 |
1987年 | 1652篇 |
1986年 | 1432篇 |
1985年 | 3407篇 |
1984年 | 3782篇 |
1983年 | 2539篇 |
1982年 | 2988篇 |
1981年 | 2502篇 |
1980年 | 2186篇 |
1979年 | 1874篇 |
1978年 | 1523篇 |
1977年 | 1304篇 |
1976年 | 1324篇 |
1975年 | 896篇 |
1974年 | 829篇 |
排序方式: 共有10000条查询结果,搜索用时 17 毫秒
1.
2.
目的:探讨基于虚拟教研室的公共卫生安全素养培育课程构建及实践。方法:选取某医学院校专科护理专业学生(护生)为研究对象,将护理1班45人作为试验组,将护理2班43人作为对照组,对照组对公共卫生安全知识实施线上与线下的常规教学,试验组实施基于虚拟教研室的公共卫生安全素养培育课程。比较两组护生内容掌握情况及学习满意度。结果:试验组护生的学习成绩明显高于对照组(P<0.01),试验组护生对教学的满意度为95.6%(43/45),明显高于对照组(P<0.05)。结论:基于虚拟教研室的公共卫生安全素养培育课程构建既可以广泛促进不同专业教师进行教学研究交流,全面提高教师教书育人能力,又可以使护生在学习过程中接触不同专业、不同领域的知识与技能,注重护生主体作用,提高学习效果和学习满意度。 相似文献
3.
目的 基于《国际功能、残疾和健康分类》(ICF)构建智力和发展性残疾儿童青少年身体活动效益系统综述的范畴和PICO架构,探讨智力和发展性残疾儿童和青少年参加身体活动的健康效益。 相似文献
4.
【目的】 对术语使用情况进行调研,找出术语使用不规范的问题,为提升我国科技期刊术语规范化水平、推进科技期刊高质量发展提供依据。【方法】 采用回顾性调查方法,选择18种科技期刊2020年全年刊出的所有文章,调查其中术语使用差错情况。【结果】 术语相关差错主要涉及术语使用规范问题、术语编校规范问题及专有名词术语规范问题,具体差错类型比较多样化,不利于期刊质量及影响力的提升,应引起论文作者及期刊工作者的高度重视。术语相关差错中,术语使用规范问题最为突出;术语使用规范问题的各种类型中,术语形音义相近而误的现象最为突出。【结论】 我国科技期刊术语规范化水平有待提升,需要引起重视。 相似文献
5.
《Health & place》2022
The aim of this study was to examine if citizen science contributes to gaining insight into community health and to the health of the citizen scientists themselves. Therefore, thirteen citizens in four deprived neighbourhoods were trained as citizen scientists to conduct research in their own communities. Results showed that the citizen scientists identified forty (health related) themes in their communities. The citizen scientists reported an increase in their overall self-perceived health which, however, was not significantly demonstrated in the prequestionnaire and postquestionnaire. 相似文献
6.
《Vaccine》2022,40(52):7604-7612
Background and ObjectiveVaccine uptake during pregnancy remains low. Our objectives were to describe 1) development and adaptation of a clinician communication training intervention for maternal immunizations and 2) obstetrics and gynecology (ob-gyn) clinician and staff perspectives on the intervention and fit for the prenatal care context.MethodsDesign of the Motivational Interviewing for Maternal Immunizations (MI4MI) intervention was based on similar communication training interventions for pediatric settings and included presumptive initiation of vaccine recommendations (“You’re due for two vaccines today”) combined with motivational interviewing (MI) for hesitant patients. Interviews and focus group discussions were conducted with ob-gyn clinicians and staff in five Colorado clinics including settings with obstetric physicians, certified nurse midwives (CNMs), and clinician-trainees. Participants were asked about adapting training to the ob-gyn setting and their implementation experiences. Feedback was incorporated through iterative changes to training components.ResultsInterview and focus group discussion results from participants before (n = 3), during (n = 11) and after (n = 25) implementation guided intervention development and adaptation. Three virtual, asynchronous training components were created: a video and two interactive modules. This virtual format was favored due to challenges attending group meetings; however, participants noted opportunities to practice skills through role-play were lacking. Training modules were adapted to include common challenging vaccine conversations and live-action videos. Participants liked interactive training components and use of adult learning strategies. Some participants initially resisted the presumptive approach but later found it useful after applying it in their practices. Overall, participants reported that MI4MI training fit well with the prenatal context and recommended more inclusion of non-clinician staff.ConclusionsMI4MI training was viewed as relevant and useful for ob-gyn clinicians and staff. Suggestions included making training more interactive, and including more complex scenarios and non-clinician staff. 相似文献
7.
《Health & place》2022
An accumulating body of evidence has associated exposure to greenspace with improved birth outcomes, including higher birth weight and lower risk of low birth weight; however, evidence on such association with in-utero fetal growth is scarce. We explored the influence of maternal exposure to residential greenspace and fetal growth in four INMA (Infancia y Medio Ambiente) Spanish birth cohorts (2003–2008), with 2,465 participants. Residential greenspace was characterised by the Normalised Difference Vegetation Index (NDVI) average across 100 m, 300 m, and 500 m buffers around the residence. Repeated ultrasound measurements of the abdominal circumference (AC), biparietal diameter (BPD), femur length (FL), and estimated fetal weight (EFW) were used. We created customised-generalised least squares models to evaluate associations of residential greenspace exposure on each fetal growth parameter, controlled for the relevant confounders. There were associations between the 500 m buffer and BPD, FL, and AC. We also found associations in the 300 m buffer and FL and AC. The associations in the 100 m buffer were null. Estimates were higher among participants with lower socioeconomic status. Mediation analyses found that air pollution might explain 15–37% of our associations. Mediation by physical activity was not observed. Greenspace exposure may be beneficial for fetal growth. 相似文献
8.
9.
目的 本实验采用HPLC方法建立来自3个产地15批怀牛膝药材的指纹图谱,并对β-蜕皮甾酮,25R-牛膝甾酮,25S-牛膝甾酮进行含量测定,同时通过化学计量学的方法对15批怀牛膝进行质量评价。方法 选用Waters SunFire C18(150 mm×4.6 mm,5 μm)色谱柱,检测波长280 nm,以乙腈-0.1%甲酸水梯度洗脱,流速为1.0 mL·min-1,柱温25℃,进样量10 μL。以β-蜕皮甾酮峰为参照峰,运用软件《中药色谱指纹图谱相似度评价系统(2012版)》对15批怀牛膝药材进行相似度分析,使用Metabo Analyst 5.0网站进行聚类热图分析,使用SIMCA 14.1软件进行PCA和PLS-DA分析。结果 标定了31个共有指纹峰,指认了3个已知成分,并对其进行含量测定,化学计量学分析结果将15批怀牛膝药材样品分为3类,并且筛选了不同产地间潜在的差异性成分。结论 该方法具有良好的精密度、重复性以及稳定性,可为怀牛膝的质量评价与控制提供科学依据及参考。 相似文献
10.
《Journal of the American Dental Association (1939)》2022,153(5):414-420
BackgroundRepairing crowns with defective margins is minimally invasive and cost-effective compared with replacement. The authors’ objectives were to examine the survival trajectory of crown margin repairs and to determine the factors associated with survival.MethodsRecords of adult patients from January 2008 through August 2019 were reviewed for crown margin repairs completed at University of Iowa College of Dentistry. A total of 1,002 crown margin repairs were found. Each repair was followed through the end of study in 2019 or until an event (for example, additional repair, endodontic treatment, crown replacement, or extraction). A Cox proportional hazards model was used to study the relationship between selected covariates and time to event.ResultsDuring the follow-up period, 32.8% of the repairs needed reintervention. In the final model, repair material was the only significant covariate. No difference was found between the survival of repairs done with resin-modified glass ionomer and amalgam. However, the repairs done with resin-based composite and conventional glass ionomer were more likely (1.5 times: 95% CI, 1.02 to 2.10 times; and 2 times: 95% CI, 1.40 to 2.73 times, respectively) to need reintervention than were those done with amalgam.ConclusionsMedian survival time of crown margin repairs was 5.1 years (95% CI, 4.48 to 5.72 years). Median survival times for amalgam, resin-modified glass ionomer, resin-based composite, and glass ionomer repair materials were 5.7 years (95% CI, 4.80 to 6.25 years), 5.3 years (95% CI, 4.73 to 6.34 years), 3.2 years (95% CI, 2.51 to 6.19 years), and 3.0 years (95% CI, 2.53 to 3.62 years), respectively.Practical ImplicationsWhen considering crown margin repairs, resin-modified glass ionomer or amalgam is preferable to resin-based composite or glass ionomer. 相似文献