全文获取类型
收费全文 | 123437篇 |
免费 | 10795篇 |
国内免费 | 3369篇 |
专业分类
耳鼻咽喉 | 632篇 |
儿科学 | 3492篇 |
妇产科学 | 3176篇 |
基础医学 | 12156篇 |
口腔科学 | 2409篇 |
临床医学 | 12530篇 |
内科学 | 28402篇 |
皮肤病学 | 1291篇 |
神经病学 | 7002篇 |
特种医学 | 2333篇 |
外国民族医学 | 8篇 |
外科学 | 7614篇 |
综合类 | 18562篇 |
现状与发展 | 14篇 |
一般理论 | 11篇 |
预防医学 | 10787篇 |
眼科学 | 2899篇 |
药学 | 13449篇 |
108篇 | |
中国医学 | 7417篇 |
肿瘤学 | 3309篇 |
出版年
2024年 | 292篇 |
2023年 | 2452篇 |
2022年 | 2816篇 |
2021年 | 5747篇 |
2020年 | 5180篇 |
2019年 | 4958篇 |
2018年 | 4738篇 |
2017年 | 4634篇 |
2016年 | 4746篇 |
2015年 | 4491篇 |
2014年 | 7752篇 |
2013年 | 9994篇 |
2012年 | 7127篇 |
2011年 | 7744篇 |
2010年 | 6172篇 |
2009年 | 5796篇 |
2008年 | 5621篇 |
2007年 | 5490篇 |
2006年 | 4818篇 |
2005年 | 4314篇 |
2004年 | 3642篇 |
2003年 | 3223篇 |
2002年 | 2594篇 |
2001年 | 2449篇 |
2000年 | 1982篇 |
1999年 | 1787篇 |
1998年 | 1566篇 |
1997年 | 1494篇 |
1996年 | 1357篇 |
1995年 | 1256篇 |
1994年 | 1109篇 |
1993年 | 993篇 |
1992年 | 911篇 |
1991年 | 784篇 |
1990年 | 762篇 |
1989年 | 687篇 |
1988年 | 552篇 |
1987年 | 461篇 |
1986年 | 506篇 |
1985年 | 636篇 |
1984年 | 631篇 |
1983年 | 347篇 |
1982年 | 508篇 |
1981年 | 388篇 |
1980年 | 415篇 |
1979年 | 286篇 |
1978年 | 249篇 |
1977年 | 223篇 |
1976年 | 197篇 |
1975年 | 130篇 |
排序方式: 共有10000条查询结果,搜索用时 27 毫秒
61.
Objectives:To reassess the long-term camouflage effects of resin infiltration (Icon, DMG, Hamburg, Germany) of white spot lesions (WSL) and sound adjacent enamel (SAE) achieved in a previous trial. The null hypothesis was tested that there were no significantly different CIE-L*a*b*-ΔE-values between WSL and SAE areas of assessment after at least 24 months (T24) compared to those at baseline (T0).Materials and Methods:Of twenty subjects who received previous resin infiltration treatment of nteeth = 111 nonrestored, noncavitated postorthodontic WSL after multibracket treatment during a randomized controlled trial and were contacted 20 months after baseline, eight subjects (trial teeth nteeth = 40; m/f ratio 1/7; age range (mean; SD) 12–17 [15.25; 2.12] years); response rate: 40%) were available for follow-up after at least 24 months (T24). CIE-L*a*b* differences between summarized color and lightness values (ΔEWSL/SAE) of WSL and SAE were assessed using a spectrophotometer and compared to baseline data assessed prior to infiltration (T0), and those after 6 (T6), and 12 (T12) months using paired t tests at a significance level of α = 5%.Results:T24 assessments were performed after a mean 33.86 (SD: 8.64; Min: 24; Max: 45) months following T0. Mean (SD) ΔEWSL/SAE units of available teeth were 8.76 (5.33) at baseline; 5.5 (2.75) at T6; 5.2 (2.41) at T12; and 5.57 (2.6) at T24. Comparisons of T6, T12, and T24 with T0 yielded highly significant differences, whereas T6–T24 and T12–T24 differences were found to be not significant.Conclusions:Assimilation of infiltrated WSL to the color of adjacent enamel by resin infiltration is considered to be suitable for the long-term improvement in the esthetic appearance of postorthodontic WSL. 相似文献
62.
63.
《Health Policy and Technology》2022,11(3):100647
BackgroundUnequal housing access resulted in more than 150 million homeless people worldwide, with millions more expected to be added every year due to the ongoing climate-related crises. Homeless population has a counterproductive effect on the social, psychological integration efforts by the community and exposure to other severe health-related issues. Geographic Information Systems (GIS) have long been applied in urban planning and policy, housing and homelessness, and health-related research.MethodsWe used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method to systematically review 24 articles collected from multiple databases (n = 10) that focused on health-related issues among homeless people and used geospatial analysis techniques in their research.ResultsOur findings indicated a geographic clustering of case study locations– 26 out of the 31 case study sites are from the USA and Canada. Studies used spatial analysis techniques to identify hotspots, clusters and patterns of patient location and population distribution. Studies also reported relationships among the location of homeless shelters and substance use, discarded needles, different infectious and non-infectious disease clusters.ConclusionMost studies were restricted in analyzing and visualizing the patterns and disease clusters; however, geospatial analyses techniques are useful and offer diverse techniques for a more sophisticated understanding of the spatial characteristics of the health issues among homeless people. Better integration of GIS in health research among the homeless would help formulate sensible policies to counter health inequities among this vulnerable population group. 相似文献
64.
65.
66.
67.
《The Journal for Nurse Practitioners》2022,18(8):897-903
Low-income food pantry clients are unable to adhere to the diet and physical activity recommendations of the American Diabetes Association. The aim of the study is to test the feasibility of using a mobile phone app to improve diabetes medication adherence. Clients with uncontrolled type 2 diabetes were enrolled in a mobile phone app featuring 70 days of text message reminders and incentives. The app and the 4-item Morisky Medication Adherence Scale evaluated medication adherence. Clinically significant medication adherence of 93% was achieved with use of the app. Phone app use is feasible among urban low-income clients to improve medication adherence. 相似文献
68.
通过回顾分析我院2例确诊为胰岛素自身免疫综合征(IAS)患者的临床资料,并复习相关文献,总结发病机制及治疗方法,探讨IAS患者的临床特点,提高对低血糖症的诊治水平。 相似文献
69.
《Health & place》2022
Background and objectivesRecent research has identified neighborhoods as an important contributor to later-life frailty. However, little is known about how neighborhood resources are associated with frailty trajectories over time, especially in developing countries. This study examines the impact of neighborhood physical and social resources on the trajectories of frailty over time among older people in China.Research design and methodsUsing the four waves of the China Health and Retirement Longitudinal Study (2011–2018), 5673 respondents aged 60 and above at baseline were included for analyses. Multilevel growth modeling was fitted to estimate the effects of neighborhood resources on frailty trajectories over a 7-year period, controlling for individual-level characteristics.ResultsOlder Chinese people who lived in neighborhoods with better basic infrastructures and a greater number of voluntary organizations were less frail at baseline. Accessible exercise facilities were associated with a lower initial level of frailty only among rural older adults, while higher community-level socioeconomic status (SES) was associated with a lower initial level of frailty only among urban older adults. Over the 7-year follow-up period, better basic infrastructures and accessible exercise facilities were associated with a slower increase rate of frailty scores among rural residents.Discussion and implicationsNeighborhood resources are important contributors to the level of frailty among older Chinese people. Our findings of significant urban-rural differences have important implications for designing and implementing infrastructure development and community building programs in rural and urban China. 相似文献
70.
目的:观察理气中药经验组方对糖尿病大鼠胃排空延迟的干预作用。方法:雌雄各半成年SD大鼠110只,随机分为正常组(A组)、糖尿病中药组(B组)、糖尿病胃复安组(C组)、糖尿病组(D组)。A组、D组1次/d按10 mL/只予0.9%生理盐水灌胃,B组1次/d按8 mL/只予中药煎剂灌胃,C组1次/d按0.5 mg/只予胃复安片灌胃。喂养12周后,行13C胃排空实验及甲基橙水溶液胃排空实验,观察各组大鼠胃排空情况。结果:糖尿病大鼠胃排空较正常大鼠明显延迟(P0.01),糖尿病大鼠胃排空延迟模型制作成功。糖尿病中药组和糖尿病胃复安组大鼠胃排空较糖尿病组快(P0.01);糖尿病中药组大鼠胃排空较糖尿病胃复安组大鼠快(P0.05)。结论:常规喂养12周后糖尿病大鼠出现胃排空延迟。理气中药陈皮、枳实、木香、香附组方煎剂和胃复安均能促进糖尿病大鼠胃排空,理气中药组方煎剂的效果优于胃复安。 相似文献