首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   168篇
  免费   7篇
  国内免费   1篇
儿科学   1篇
妇产科学   2篇
基础医学   21篇
口腔科学   1篇
临床医学   11篇
内科学   9篇
神经病学   11篇
特种医学   28篇
外科学   5篇
综合类   9篇
预防医学   33篇
眼科学   4篇
药学   16篇
中国医学   4篇
肿瘤学   21篇
  2023年   4篇
  2022年   4篇
  2021年   4篇
  2020年   3篇
  2019年   3篇
  2018年   9篇
  2017年   5篇
  2016年   1篇
  2015年   3篇
  2014年   16篇
  2013年   4篇
  2012年   9篇
  2011年   19篇
  2010年   19篇
  2009年   7篇
  2008年   19篇
  2007年   12篇
  2006年   5篇
  2005年   6篇
  2004年   2篇
  2003年   4篇
  2001年   3篇
  2000年   3篇
  1999年   2篇
  1998年   3篇
  1996年   2篇
  1994年   2篇
  1993年   1篇
  1985年   1篇
  1984年   1篇
排序方式: 共有176条查询结果,搜索用时 93 毫秒
1.
心电图机应用过程中的质量保证   总被引:1,自引:0,他引:1  
心电图机应用过程中的质量保证对其向临床提供准确可信的测量参数和诊断结果具有重要意义。在多年实践摸索和理论分析的基础上,本文从心电图机使用前的条件准备、心电描记过程中的质量控制、日常的维护保养以及计量检测等环节人手,研究并提出了一套规范的质量保证方案,以确保心电检查数据的准确性和临床心电诊断的质量。  相似文献   
2.
Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (CAS Reg. No. 2082-79-3), currently marketed as Irganox 1076 (I-76), is a sterically hindered phenolic antioxidant used in a variety of organic substrates, including those used in the manufacture of food contact articles. In 2012, the US Food and Drug Administration (USFDA), Office of Food Additive Safety (OFAS), initiated a post-market re-evaluation of the food contact applications of I-76. This project aimed to ensure that current dietary exposures from the use of I-76 in food contact articles are accurately captured and the safety assessment considered all relevant and available toxicological information. To accomplish these aims, the USFDA reviewed the available toxicological studies and chemistry information on food contact applications of I-76. Based on this in-depth analysis, a NOAEL of 64 mg/kg-bw/d (female rats) from a chronic rat study and a cumulative estimated dietary intake (CEDI) of 4.5 mg/p/d, was used to calculate a margin of exposure (MOE) of ∼850. We concluded that the previous and current exposure levels provide an adequate margin of safety (MOS) and remain protective of human health for the regulated uses.  相似文献   
3.
This review summarizes recent developments that have contributed to understand how adenosine receptors, particularly A2A receptors, modulate brain injury in various animal models of neurological disorders, including Parkinson's disease (PD), stroke, Huntington's disease (HD), multiple sclerosis, Alzheimer's disease (AD) and HIV-associated dementia. It is clear that extracellular adenosine acting at adenosine receptors influences the functional outcome in a broad spectrum of brain injuries, indicating that A2A Rs may modulate some general cellular processes to affect neuronal cells death. Pharmacological, neurochemical and molecular/genetic approaches to the complex actions of A2A receptors in different cellular elements suggest that A2A receptor activation can be detrimental or protective after brain insults, depending on the nature of brain injury and associated pathological conditions. An interesting concept that emerges from these studies is A2A R's ability to fine tune neuronal and glial functions to produce neuroprotective effects. While the data presented here clearly highlight the complexity of using adenosinergic agents therapeutically in PD and other neurodegenerative disorders and point out many areas for further inquiry, they also confirm that adenosine receptor ligands, particularly A2A receptor ligands, have many promising characteristics that encourage the pursuit of their therapeutic potential.  相似文献   
4.
Adenosine A2A receptors and basal ganglia physiology   总被引:2,自引:0,他引:2  
Adenosine A2A receptors are highly enriched in the basal ganglia system. They are predominantly expressed in enkephalin-expressing GABAergic striatopallidal neurons and therefore are highly relevant to the function of the indirect efferent pathway of the basal ganglia system. In these GABAergic enkephalinergic neurons, the A2A receptor tightly interacts structurally and functionally with the dopamine D2 receptor. Both by forming receptor heteromers and by targeting common intracellular signaling cascades, A2A and D2 receptors exhibit reciprocal antagonistic interactions that are central to the function of the indirect pathway and hence to basal ganglia control of movement, motor learning, motivation and reward. Consequently, this A2A/D2 receptors antagonistic interaction is also central to basal ganglia dysfunction in Parkinson's disease. However, recent evidence demonstrates that, in addition to this post-synaptic site of action, striatal A2A receptors are also expressed and have physiological relevance on pre-synaptic glutamatergic terminals of the cortico-limbic-striatal and thalamo-striatal pathways, where they form heteromeric receptor complexes with adenosine A1 receptors. Therefore, A2A receptors play an important fine-tuning role, boosting the efficiency of glutamatergic information flow in the indirect pathway by exerting control, either pre- and/or post-synaptically, over other key modulators of glutamatergic synapses, including D2 receptors, group I metabotropic mGlu5 glutamate receptors and cannabinoid CB1 receptors, and by triggering the cAMP-protein kinase A signaling cascade.  相似文献   
5.
6.
Objective To probe into the protective mechanism of electro-acupuncture (EA) on anti-oxygen stress in dementia-model rats. Methods A total of 30 male SD rats of cleaning grade were randomized into three groups, named sham-operation (n = 10), model (n = 10), model+ EA (n = 10). The dementia-model rat was made with hippocampal GA1 lesions by quinolinic acid (QA). On the second day of modeling, in model+ EA group, EA (3 Hz, 2-4 mA, continuous waves) was applied to "Dàzhuī" (大椎 GV 14) and "Shènshū" (肾俞 BL 23) for 10 min. The capability of learning and memory was evaluated by step-down test to observe the changes of nitric oxide (NO), nitric oxide synthase (NOS) activity, superoxide dismutase (SOD) activity and malondialdehyde (MDA) of the hippocampal tissues in rats separately by biochemical methods. Results EA improved learning and memory of dementia rats with hippocampal CA1 lesions induced by QA at different degrees. It significantly increased SOD activity, reduced MDA content and improved NO level and NOS activity. Conclusion EA improves significantly the learning and memory of the dementia rats due to hippocampal CA1 lesions induced by QA, which is probably relevant with the anti-oxygen stress of EA.  相似文献   
7.
本文论述了机动门脉动真空灭菌器在使用中的科学化管理,质量保证(QA)与质量控制(QC)及预防性维修。  相似文献   
8.
放射物理技术质量保证是肿瘤放射治疗质量保证中的一个重要方面。简述了DailyQA3日常质量保证仪的组成及工作原理,介绍了其在肿瘤放射物理技术质量保证中的使用方法和应用体会,并评价了其性能优缺点。总体来讲,Daily QA 3可以方便、快捷地满足日常的肿瘤放射物理技术质量,保证工作的需要。  相似文献   
9.
王洵  汪月莉 《医疗卫生装备》2008,29(10):111-111
放射物理技术质量保证是肿瘤放射治疗质量保证中的一个重要方面。简述了Daily QA3日常质量保证仪的组成及工作原理,介绍了其在肿瘤放射物理技术质量保证中的使用方法和应用体会,并评价了其性能优缺点。总体来讲,Daily QA3可以方便、快捷地满足日常的肿瘤放射物理技术质量,保证工作的需要。  相似文献   
10.
本文论述了质量保证(QA)在长期毒性试验原始资料核查过程中的关注点和主要问题,包括方案、报告和原始记录的一致性、原始资料记录的规范性和准确性、数据核查和资料保存等。分析问题产生的原因,主要归结于GLP意识不强、GLP依从性和SOP的执行力差。对减少问题发生提出了建议和措施,包括加强GLP培训、提高对GLP和SOP的依从性、计算机化仪器系统的运用和专家对GLP单位实施飞行检查等。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号