全文获取类型
收费全文 | 122247篇 |
免费 | 10852篇 |
国内免费 | 4343篇 |
专业分类
耳鼻咽喉 | 942篇 |
儿科学 | 1838篇 |
妇产科学 | 2989篇 |
基础医学 | 14690篇 |
口腔科学 | 2961篇 |
临床医学 | 11175篇 |
内科学 | 13627篇 |
皮肤病学 | 1446篇 |
神经病学 | 9143篇 |
特种医学 | 5612篇 |
外国民族医学 | 17篇 |
外科学 | 10763篇 |
综合类 | 19421篇 |
现状与发展 | 11篇 |
一般理论 | 7篇 |
预防医学 | 12604篇 |
眼科学 | 2769篇 |
药学 | 13404篇 |
153篇 | |
中国医学 | 7905篇 |
肿瘤学 | 5965篇 |
出版年
2024年 | 217篇 |
2023年 | 1973篇 |
2022年 | 2711篇 |
2021年 | 5034篇 |
2020年 | 4592篇 |
2019年 | 4194篇 |
2018年 | 4062篇 |
2017年 | 4292篇 |
2016年 | 4187篇 |
2015年 | 4326篇 |
2014年 | 7474篇 |
2013年 | 8900篇 |
2012年 | 7171篇 |
2011年 | 8081篇 |
2010年 | 6403篇 |
2009年 | 6131篇 |
2008年 | 6072篇 |
2007年 | 6056篇 |
2006年 | 5345篇 |
2005年 | 4876篇 |
2004年 | 4040篇 |
2003年 | 3742篇 |
2002年 | 2873篇 |
2001年 | 2712篇 |
2000年 | 2336篇 |
1999年 | 2079篇 |
1998年 | 1747篇 |
1997年 | 1698篇 |
1996年 | 1264篇 |
1995年 | 1402篇 |
1994年 | 1230篇 |
1993年 | 1000篇 |
1992年 | 940篇 |
1991年 | 774篇 |
1990年 | 784篇 |
1989年 | 685篇 |
1988年 | 514篇 |
1987年 | 470篇 |
1986年 | 488篇 |
1985年 | 688篇 |
1984年 | 610篇 |
1983年 | 384篇 |
1982年 | 471篇 |
1981年 | 394篇 |
1980年 | 402篇 |
1979年 | 303篇 |
1978年 | 240篇 |
1977年 | 230篇 |
1976年 | 206篇 |
1975年 | 150篇 |
排序方式: 共有10000条查询结果,搜索用时 281 毫秒
1.
2.
3.
In clinical and epidemiological studies, there is a growing interest in studying the heterogeneity among patients based on longitudinal characteristics to identify subtypes of the study population. Compared to clustering a single longitudinal marker, simultaneously clustering multiple longitudinal markers allow additional information to be incorporated into the clustering process, which reveals co-existing longitudinal patterns and generates deeper biological insight. In the current study, we propose a Bayesian consensus clustering (BCC) model for multivariate longitudinal data. Instead of arriving at a single overall clustering, the proposed model allows each marker to follow marker-specific local clustering and these local clusterings are aggregated to find a global (consensus) clustering. To estimate the posterior distribution of model parameters, a Gibbs sampling algorithm is proposed. We apply our proposed model to the primary biliary cirrhosis study to identify patient subtypes that may be associated with their prognosis. We also perform simulation studies to compare the clustering performance between the proposed model and existing models under several scenarios. The results demonstrate that the proposed BCC model serves as a useful tool for clustering multivariate longitudinal data. 相似文献
4.
目的探讨衰减伪影对冠心病患者门控心肌灌注显像(GMPI)图像质量及灌注结果的影响。资料与方法回顾性分析2020年3月—2021年3月在郑州大学第一附属医院核医学科经冠状动脉造影证实且于造影前后1周行GMPI的99例冠心病患者的图像,定性及半定量分析衰减校正前后GMPI图像结果,比较衰减校正前后左心室各壁段平均放射性计数及灌注结果的差异,进一步分析衰减校正前后灌注结果不一致部分的受检者的节段性室壁运动及增厚情况。结果与衰减校正前比较,衰减校正后左心室间隔、下后壁及侧壁的平均放射性计数较高(Z=-7.302、-8.014、-3.991,P均<0.001),心尖部较低(Z=-8.021,P<0.001)。其中女性衰减校正后前壁平均放射性计数减低(Z=-2.314,P=0.021)。男性衰减校正前后下后壁放射性计数差值明显高于女性(t=-8.408,P<0.05)。衰减校正后44%(44/99)的左前降支及37%(37/99)的右冠状动脉分支供血区域显像结果发生改变,结合超声心动图及GMPI结果显示其中85%(35/41)的左前降支及81%(29/36)的右冠状动脉分支供血区域室壁运动及室壁增厚率均正常。结论衰减伪影对GMPI的图像质量和灌注结果有较大影响,结合室壁运动和增厚情况等有助于鉴别衰减伪影,提高诊断准确度与特异度。 相似文献
5.
《Cirugía espa?ola》2022,100(3):149-153
IntroductionThe Law for the Regulation of Health Professions (LOPS) indicates that health professionals will carry out continuous training throughout their professional life, and will regularly prove their professional competence. The objective of the study was to carry out a national survey to find out the opinion of Spanish surgeons and thus be able to prepare a recertification project by the Spanish Association of Surgeons (AEC).MethodsCross-sectional observational study carried out in June-July 2020, through a survey sent to the members of the AEC.ResultsThe survey had a total of 1230 visits and an overall completion rate of 784 responses (67.3%). 69.6% were unaware of the LOPS forecasts and 83.4% were unaware of similar initiatives in other specialties and 95.5% agreed to demand adequate information. 71.4% believed it necessary but only 57% believed that it should be mandatory. 82.9% would agree that it should be regulated through an objective and predictable official procedure.ConclusionsThe concept of re-accreditation is not well known in our specialty and in view of the results obtained, adequate and reliable information seems necessary. Therefore, it would be pertinent to propose by the AEC a specific project to assess activities and skills. 相似文献
6.
Collagens are the most abundant proteins in the extracellular matrix. They provide a framework to build organs and tissues and give structural support to make them resistant to mechanical load and forces. Several intra‐ and extracellular modifications are needed to make functional collagen molecules, intracellular post‐translational modifications of proline and lysine residues having key roles in this. In this article, we provide a review on the enzymes responsible for the proline and lysine modifications, that is collagen prolyl 4‐hydroxylases, 3‐hydroxylases and lysyl hydroxylases, and discuss their biological functions and involvement in diseases. 相似文献
7.
Hannah C. Nordhues Anjali Bhagra Natya N. Stroud Jennifer A. Vencill Carol L. Kuhle 《Mayo Clinic proceedings. Mayo Clinic》2021,96(7):1907-1920
The coronavirus disease 2019 (COVID-19) pandemic has rapidly created widespread impacts on global health and the economy. Data suggest that women are less susceptible to severe illness. However, sex-disaggregated data are incomplete, leaving room for misinterpretation, and focusing only on biologic sex underestimates the gendered impact of the pandemic on women. This narrative review summarizes what is known about gender disparities during the COVID-19 pandemic and the economic, domestic, and health burdens along with overlapping vulnerabilities related to the pandemic. In addition, this review outlines recommended strategies that advocacy groups, community leaders, and policymakers should implement to mitigate the widening gender disparities related to COVID-19. 相似文献
8.
深化家庭医生签约服务是深化医药卫生体制改革、强化基层医疗卫生服务、实现"健康中国"战略目标的重要选择,也是当前更好维护人民群众健康的重要途径。为有效推进签约服务工作,国家陆续推出各项政策,全国各地也在积极进行实践探索,成效明显。但是,签约服务仍面临诸多问题,其中"执行难"是签约服务深度推进的一大困境。通过史密斯政策执行过程模型,结合签约服务政策执行过程,发现签约服务仍存在法治性不足、政策执行人员水平不高、激励不足、政策环境影响等诸多制约因素。因此,需要从法律和制度方面进行顶层设计、提升执行人员素质和职业认同、建立医患互信、优化政策执行环境等角度进行政策创新,探索家庭医生签约服务可持续发展的路径。 相似文献
9.
10.