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   709134篇
  免费   49592篇
  国内免费   1239篇
耳鼻咽喉   9298篇
儿科学   23283篇
妇产科学   17775篇
基础医学   110859篇
口腔科学   20142篇
临床医学   63460篇
内科学   134919篇
皮肤病学   16280篇
神经病学   49857篇
特种医学   26019篇
外国民族医学   77篇
外科学   105603篇
综合类   14800篇
一般理论   161篇
预防医学   51149篇
眼科学   16350篇
药学   54377篇
  3篇
中国医学   2321篇
肿瘤学   43232篇
  2019年   5406篇
  2018年   7836篇
  2017年   6127篇
  2016年   6834篇
  2015年   7574篇
  2014年   10413篇
  2013年   15533篇
  2012年   20855篇
  2011年   21920篇
  2010年   12948篇
  2009年   12155篇
  2008年   20376篇
  2007年   21934篇
  2006年   22319篇
  2005年   20843篇
  2004年   20427篇
  2003年   19314篇
  2002年   18870篇
  2001年   36621篇
  2000年   37180篇
  1999年   30522篇
  1998年   7644篇
  1997年   6393篇
  1996年   6660篇
  1995年   6674篇
  1994年   6128篇
  1993年   5636篇
  1992年   23188篇
  1991年   23141篇
  1990年   22528篇
  1989年   22267篇
  1988年   20194篇
  1987年   19572篇
  1986年   18602篇
  1985年   17449篇
  1984年   12788篇
  1983年   10827篇
  1982年   5942篇
  1979年   11559篇
  1978年   8177篇
  1977年   6871篇
  1976年   6601篇
  1975年   7299篇
  1974年   8532篇
  1973年   8162篇
  1972年   7696篇
  1971年   7147篇
  1970年   6903篇
  1969年   6339篇
  1968年   5830篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Modified-release opioids are often prescribed for the management of moderate to severe acute pain following total hip and knee arthroplasty, despite recommendations against their use due to increasing concerns regarding harm. The primary objective of this multicentre study was to examine the impact of modified-release opioid use on the incidence of opioid-related adverse events compared with immediate-release opioid use, among adult inpatients following total hip or knee arthroplasty. Data for total hip and knee arthroplasty inpatients receiving an opioid analgesic for postoperative analgesia during hospitalisation were collected from electronic medical records of three tertiary metropolitan hospitals in Australia. The primary outcome was the incidence of opioid-related adverse events during hospital admission. Patients who received modified with or without immediate-release opioids were matched to those receiving immediate-release opioids only (1:1) using nearest neighbour propensity score matching with patient and clinical characteristics as covariates. This included total opioid dose received. In the matched cohorts, patients given modified-release opioids (n = 347) experienced a higher incidence of opioid-related adverse events overall, compared with those given immediate-release opioids only (20.5%, 71/347 vs. 12.7%, 44/347; difference in proportions 7.8% [95%CI 2.3–13.3%]). Modified-release opioid use was associated with an increased risk of harm when used for acute pain during hospitalisation after total hip or knee arthroplasty.  相似文献   
3.
崔娜  王小刚  董磊 《西部医学》2022,34(8):1230-1234
目的 探讨血管内超声虚拟组织学成像(VH-IVUS)与实时剪切弹性成像技术(SWE)评估颈动脉斑块稳定性及脑梗死的价值。方法 选取2018年12月~2020年12月在中国人民解放军联勤保障部队第960医院就诊的颈动脉粥样硬化斑块患者130例(201个斑块),分析不同性质斑块VH-IVUS评分及平均杨氏模量差异,及评估稳定性斑块的价值。130例颈动脉粥样硬化斑块患者近期发生脑梗死53例(脑梗死组),无脑梗死77例(无脑梗死组),比较两组甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、VH-IVU评分及平均杨氏模量水平,同时分析VH-IVUS评分及平均杨氏模量评估脑梗死的价值。结果 易损性斑块VH-IVUS评分高于稳定性斑块(P<0.05),而平均杨氏模量低于稳定性斑块(P<0.05);VH-IVUS评分、平均杨氏模量评估稳定性斑块的ROC曲线下面积分别为0.789和0.875。脑梗死组TG、LDL-C明显高于无脑梗死组(P<0.05),而HDL-C明显低于无脑梗死组(P<0.05);脑梗死组斑块VH-IVUS评分明显高于无脑梗死组(P<0.05),而平均杨氏模量明显低于无脑梗死组(P<0.05);VH-IVUS评分、平均杨氏模量评估脑梗死的ROC曲线下面积分别为0.658和0.822。结论 VH-IVUS与SWE技术评估颈动脉斑块稳定性及脑梗死方面有较好的价值,其中SWE评估价值较高。  相似文献   
4.
目的了解临床护士工作自主性与行为目标达成度现状,并探讨两者的相关性,为提高护士行为目标达成度提供参考。方法以方便抽样法选取临床护士286名,采用工作自主性量表、护士行为目标达成度量表进行调查。结果临床护士工作自主性得分为(5.16±1.45)分,行为目标达成度得分为(4.22±0.69)分;工作自主性与行为目标达成度呈正相关(P<0.01);多元回归分析结果显示,护理层级、婚姻状况和工作自主性是护士行为目标达成度的主要影响因素(P<0.05,P<0.01)。结论临床护士的工作自主性和行为目标达成度均处于较高水平,临床护士工作自主性越高,其行为目标达成度越好。护理管理者应重视培养护士的工作自主性,挖掘护士的工作潜能,提高护士行为目标达成度,提升优质护理服务质量。  相似文献   
5.
International Ophthalmology - To report a series of patients who developed neurotrophic keratopathy following scleral fixation of intraocular lenses. Retrospective case series of patients...  相似文献   
6.
Pharmaceutical Chemistry Journal - Metformin hydrochloride is widely used to treat diabetes mellitus. This review presents its physical and chemical properties and discusses methods of analysis...  相似文献   
7.
In the last decade, the development of new radiopharmaceuticals for the imaging and therapy of prostate cancer has been a highly active and important area of research, especially focusing on the prostate-specific membrane antigen (PSMA), an antigen which is upregulated in prostate, as well as in other tumor cells. A large variety of PSMA ligands have been radiolabeled, to date. Among the various derivatives, PSMA-617 resulted to be one of the most interesting in terms of interaction with the antigen and clinical properties, and its lutetium-177 labeled version has recently been approved by regulatory agencies for therapeutic purposes. For this reasons, the radiolabeling with fluorine-18 of a PSMA-617 derivative might be of interest. Beside other methodologies to radiolabel macromolecules with fluorine-18, the “click-chemistry” approach resulted to be very useful, and the copper-catalyzed azide-alkyne cycloaddition (CuAAC) is considered one of most efficient and reliable. This paper proposes the synthesis of a suitable precursor for the radiolabeling with fluorine-18 of a new PSMA-617 derivative. The whole radiosynthetic procedure has been fully automated, and the final product, which proved to be stable in plasma, has been obtained with radiochemical yield and purity suitable for subsequent preclinical studies.  相似文献   
8.
9.
10.
PurposeTRAPPC9 deficiency is an autosomal recessive disorder mainly associated with intellectual disability (ID), microcephaly, and obesity. Previously, TRAPPC9 deficiency has not been associated with biochemical abnormalities.MethodsExome sequencing was performed in 3 individuals with ID and dysmorphic features. N-Glycosylation analyses were performed in the patients’ blood samples to test for possible congenital disorder of glycosylation (CDG). TRAPPC9 gene, TRAPPC9 protein expression, and N-glycosylation markers were assessed in patient fibroblasts. Complementation with wild-type TRAPPC9 and immunofluorescence studies to assess TRAPPC9 expression and localization were performed. The metabolic consequences of TRAPPC9 deficiency were evaluated using tracer metabolomics.ResultsAll 3 patients carried biallelic missense variants in TRAPPC9 and presented with an N-glycosylation defect in blood, consistent with CDG type I. Extensive investigations in patient fibroblasts corroborated TRAPPC9 deficiency and an N-glycosylation defect. Tracer metabolomics revealed global metabolic changes with several affected glycosylation-related metabolites.ConclusionWe identified 3 TRAPPC9 deficient patients presenting with ID, dysmorphic features, and abnormal glycosylation. On the basis of our findings, we propose that TRAPPC9 deficiency could lead to a CDG (TRAPPC9-CDG). The finding of abnormal glycosylation in these patients is highly relevant for diagnosis, further elucidation of the pathophysiology, and management of the disease.  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