全文获取类型
收费全文 | 789篇 |
免费 | 27篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 4篇 |
妇产科学 | 2篇 |
基础医学 | 49篇 |
口腔科学 | 13篇 |
临床医学 | 89篇 |
内科学 | 80篇 |
皮肤病学 | 5篇 |
神经病学 | 25篇 |
特种医学 | 13篇 |
外科学 | 25篇 |
综合类 | 121篇 |
预防医学 | 217篇 |
眼科学 | 6篇 |
药学 | 109篇 |
中国医学 | 44篇 |
肿瘤学 | 7篇 |
出版年
2024年 | 1篇 |
2023年 | 10篇 |
2022年 | 31篇 |
2021年 | 24篇 |
2020年 | 18篇 |
2019年 | 15篇 |
2018年 | 21篇 |
2017年 | 13篇 |
2016年 | 25篇 |
2015年 | 21篇 |
2014年 | 40篇 |
2013年 | 51篇 |
2012年 | 26篇 |
2011年 | 49篇 |
2010年 | 48篇 |
2009年 | 57篇 |
2008年 | 46篇 |
2007年 | 73篇 |
2006年 | 66篇 |
2005年 | 41篇 |
2004年 | 25篇 |
2003年 | 39篇 |
2002年 | 23篇 |
2001年 | 12篇 |
2000年 | 14篇 |
1999年 | 4篇 |
1998年 | 1篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1985年 | 2篇 |
1984年 | 4篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1978年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有817条查询结果,搜索用时 15 毫秒
31.
32.
We performed biological safety evaluation tests of three Ti–Zr alloys under accelerated extraction condition. We also conducted histopathological analysis of long-term implantation of pure V, Al, Ni, Zr, Nb, and Ta metals as well as Ni–Ti and high-V-containing Ti–15V–3Al–3Sn alloys in rats. The effect of the dental implant (screw) shape on morphometrical parameters was investigated using rabbits. Moreover, we examined the maximum pullout properties of grit-blasted Ti–Zr alloys after their implantation in rabbits. The biological safety evaluation tests of three Ti–Zr alloys (Ti–15Zr–4Nb, Ti–15Zr–4Nb–1Ta, and Ti–15Zr–4Nb–4Ta) showed no adverse (negative) effects of either normal or accelerated extraction. No bone was formed around the pure V and Ni implants. The Al, Zr, Nb, and Ni–Ti implants were surrounded by new bone. The new bone formed around Ti–Ni and high-V-containing Ti alloys tended to be thinner than that formed around Ti–Zr and Ti–6Al–4V alloys. The rate of bone formation on the threaded portion in the Ti–15Zr–4Nb–4Ta dental implant was the same as that on a smooth surface. The maximum pullout loads of the grit- and shot-blasted Ti–Zr alloys increased linearly with implantation period in rabbits. The pullout load of grit-blasted Ti–Zr alloy rods was higher than that of shot-blasted ones. The surface roughness (Ra) and area ratio of residual Al2O3 particles of the Ti–15Zr–4Nb alloy surface grit-blasted with Al2O3 particles were the same as those of the grit-blasted Alloclassic stem surface. It was clarified that the grit-blasted Ti–15Zr–4Nb alloy could be used for artificial hip joint stems. 相似文献
33.
将《血站质量管理规范》、《血站实验室质量管理规范》与ISO9001:2008、ISO/1EC17025:2005质量管理体系进行融合,在兼顾各条款要素的同时,以要求较高的要素为主,建立了一体化的血站质量管理体系。 相似文献
34.
目的 探讨ISO9001质量管理体系对精神科封闭式管理医院感染控制的作用.方法 调查潍坊市精神卫生中心ISO9001质量管理体系(ISO9001-QMS)认证前2年与认证后运行6年期间所有封闭式病房出院病历,对医院感染率、感染相关因素等进行分析.结果 (1)与ISO9001-QMS认证前2年相比,认证后2年、4年、6年医院感染率比较差异均有统计学意义(P<0.01).(2) ISO9001-QMS认证前2年医院感染的相关因素为年龄、性别、病程、住院时间、疾病种类、季节(P<0.05),ISO9001-QMS认证后6年医院感染的相关因素为年龄、病程、住院时间及疾病种类(P<0.05).结论 实施ISO9001质量管理体系能有效降低精神科封闭式管理医院的院内感染率. 相似文献
35.
目的 研究ISO 7206标准对全髋关节置换术临床应用的指导意义。方法 建立肌骨数值模型,对正常行走步态进行仿真,以获得下肢的运动学和动力学参数;建立对应的全髋关节假体有限元模型,应用步态载荷进行计算,并对比ISO标准的有限元模型计算结果。结果
正常行走步态下,髋关节力分别在20%和54%步态周期出现峰值,以此作为有限元计算的步态载荷,得到20%步态周期时假体应力最大;松动模型中假体柄上最大应力大于无松动模型中假体柄上最大应力,且应力分布趋势存在差异;分析对比ISO测试和不同体重人体步态载荷下的假体最大应力,得到ISO测试中最大应力水平对应108~142 kg体重载荷下的假体最大应力。结论ISO测试中合格的假体可满足100 kg体重人体正常步态下的强度要求。 相似文献
36.
Improving the efficacy of fluoride therapies reduces dental caries and lowers fluoride exposure.BackgroundFluoride is delivered to the teeth systemically or topically to aid in the prevention of dental caries. Systemic fluoride from ingested sources is in blood serum and can be deposited only in teeth that are forming in children. Topical fluoride is from sources such as community water, processed foods, beverages, toothpastes, mouthrinses, gels, foams, and varnishes. The United States Centers for Disease Control and Prevention (CDC) and the American Dental Association (ADA) have proposed changes in their long standing recommendations for the amount of fluoride in community drinking water in response to concerns about an increasing incidence of dental fluorosis in children. Current research is focused on the development of strategies to improve fluoride efficacy. The purpose of this update is to inform the reader about new research and policies related to the use of fluoride for the prevention of dental caries.MethodsReviews of the current research and recent evidence based systematic reviews on the topics of fluoride are presented. Topics discussed include: updates on community water fluoridation research and policies; available fluoride in dentifrices; fluoride varnish compositions, use, and recommendations; and other fluoride containing dental products. This update provides insights into current research and discusses proposed policy changes for the use of fluoride for the prevention of dental caries.ConclusionsThe dental profession is adjusting their recommendations for fluoride use based on current observations of the halo effect and subsequent outcomes. The research community is focused on improving the efficacy of fluoride therapies thus reducing dental caries and lowering the amount of fluoride required for efficacy. 相似文献
37.
Janarthanan Sathananthan Stephanie Sellers Aaron Barlow Rob Fraser Viktória Stanová Anson Cheung Jian Ye Abdullah Alenezi Dale J. Murdoch Mark Hensey Danny Dvir Philipp Blanke Régis Rieu David Wood Phillippe Pibarot Jonathan Leipsic John Webb 《JACC: Cardiovascular Interventions》2018,11(17):1696-1705
Objectives
This study assessed the effect of overexpansion beyond labeled size (diameter) of transcatheter heart valves through an ex vivo bench study.Background
Transcatheter heart valves function optimally when expanded to specific dimensions. However, clinicians may sometimes wish to overexpand balloon-expandable valves to address specific clinical challenges. The implications of overexpansion have assumed considerable importance, and objective information to guide practice is limited.Methods
We evaluated SAPIEN 3 transcatheter heart valves (Edwards Lifesciences, Irvine, California). Valves (diameters of 23, 26, and 29 mm) were expanded to nominal dimensions, and then incrementally overexpanded with balloons sized 1-, 2-, and 3-mm larger than the recommended diameter. Valves underwent visual, microcomputed tomography, and hydrodynamic evaluation at various degrees of overexpansion.Results
SAPIEN 3 valves with labeled diameters of 23, 26, and 29 mm could be incrementally overexpanded to midvalve diameters of 26.4, 28.4, and 31.2 mm, respectively. With overexpansion, there was visible restriction of the valve leaflets, which was particularly evident with the smaller valves. After maximal overexpansion of a 26-mm valve a leaflet tear was observed. High-speed video demonstrated impaired leaflet motion of both the 23- and 26-mm valves and hydrodynamic testing documented a regurgitant fraction for the 23- and 26-mm valves above accepted international standards. The maximally overexpanded 29-mm SAPIEN 3 still had relatively normal leaflet motion and excellent hydrodynamic function. Durability was not specifically evaluated.Conclusions
Overexpansion of balloon-expandable valves is possible. However, excessive overexpansion may be associated with impaired hydrodynamic function, acute leaflet failure, and reduced durability. Smaller valves may be at greater risk with overexpansion than larger valves. Overexpansion is best avoided unless clinical circumstances are compelling. 相似文献38.
目的规范一次性医疗用品的管理,预防和控制医院感染的发生,杜绝医疗废物外流,防止医疗废物成为社会环境的公害源。方法采用建立文件、保持记录、过程监督的方式对一次性医疗用品的采购、使用、回收过程及其子过程进行控制。结果规范了一次性医疗用品的管理,杜绝了医疗废物的外流及由此引发的院内感染的发生。结论运用ISO9001标准中的过程方法规范一次性医疗用品的管理,可以有效地预防院内感染及环境污染,提高护理管理质量和医院绩效。 相似文献
39.
本文对国内外较为知名的期刊评价与检索体系选刊原则及其评价标准做系统综述,为科研工作者了解相关体系提供信息,同时也为期刊进入相关的评价与检索体系提供准则. 相似文献
40.
目的评价临床查房在ISO15189实验室认可准则中的作用。方法回顾性分析中山市博爱医院检验科2008年1月至2009年12月的临床查房情况,主要考核标本采集与运送、检验项目申请、危急值的登记与处理、输血质量监测、医务人员考核(检验内容)并进行评分。结果 2008~2009年检验科对全院各科室进行查房,得分较高者是眼科、重症监护病房、儿科、新生儿科,均在95分以上;体检中心与麻醉科相对欠缺。结论加强临床查房,有利于临床沟通,有利于ISO15189实验室认可准则的实施。 相似文献