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   440857篇
  免费   30971篇
  国内免费   12263篇
耳鼻咽喉   3818篇
儿科学   15491篇
妇产科学   4619篇
基础医学   35568篇
口腔科学   8200篇
临床医学   50101篇
内科学   90632篇
皮肤病学   5970篇
神经病学   39310篇
特种医学   18676篇
外国民族医学   26篇
外科学   49433篇
综合类   50040篇
一般理论   12篇
预防医学   34605篇
眼科学   6633篇
药学   39588篇
  275篇
中国医学   16597篇
肿瘤学   14497篇
  2023年   6454篇
  2022年   9628篇
  2021年   18891篇
  2020年   16749篇
  2019年   18971篇
  2018年   13626篇
  2017年   13841篇
  2016年   15140篇
  2015年   17688篇
  2014年   33441篇
  2013年   33111篇
  2012年   31687篇
  2011年   30021篇
  2010年   25613篇
  2009年   24726篇
  2008年   23404篇
  2007年   23168篇
  2006年   19999篇
  2005年   14824篇
  2004年   10211篇
  2003年   8869篇
  2002年   7399篇
  2001年   6234篇
  2000年   5280篇
  1999年   3985篇
  1998年   4075篇
  1997年   3582篇
  1996年   3137篇
  1995年   3260篇
  1994年   3082篇
  1993年   2526篇
  1992年   2659篇
  1991年   2349篇
  1990年   2106篇
  1989年   1952篇
  1988年   1774篇
  1987年   1619篇
  1986年   1352篇
  1985年   2376篇
  1984年   2395篇
  1983年   1679篇
  1982年   1815篇
  1981年   1711篇
  1980年   1438篇
  1979年   1259篇
  1978年   951篇
  1977年   939篇
  1976年   800篇
  1975年   487篇
  1974年   503篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
IntroductionOur aim was to describe practices in multimodal pain management at US children's hospitals and evaluate the association between non-opioid pain management strategies and pediatric patient-reported outcomes (PROs).MethodsData were collected as part of the 18-hospital ENhanced Recovery In CHildren Undergoing Surgery (ENRICH-US) clinical trial. Non-opioid pain management strategies included use of preoperative and postoperative non-opioid analgesics, regional anesthetic blocks, and a biobehavioral intervention. PROs included perioperative nervousness, pain-related functional disability, health-related quality of life (HRQoL). Associations were analyzed using multinomial logistic regression models.ResultsAmong 186 patients, 62 (33%) received preoperative analgesics, 186 (100%) postoperative analgesics, 81 (44%) regional anesthetic block, and 135 (73%) used a biobehavioral intervention. Patients were less likely to report worsened as compared to stable nervousness following regional anesthetic block (relative risk ratio [RRR]:0.31, 95% confidence interval [CI]:0.11–0.85), use of a biobehavioral technique (RRR:0.26, 95% CI:0.10–0.70), and both in combination (RRR:0.08, 95% CI:0.02–0.34). There were no associations of non-opioid pain control modalities with pain-related functional disability or HRQoL.ConclusionUse of postoperative non-opioid analgesics have been largely adopted, while preoperative non-opioid analgesics and regional anesthetic blocks are used less frequently. Regional anesthetic blocks and biobehavioral interventions may mitigate postoperative nervousness in children.Level of evidenceIII.  相似文献   
2.
ObjectiveThe use of mechanical circulatory support (MCS) in lung transplantation has been steadily increasing over the prior decade, with evolving strategies for incorporating support in the preoperative, intraoperative, and postoperative settings. There is significant practice variability in the use of these techniques, however, and relatively limited data to help establish institutional protocols. The objective of the AATS Clinical Practice Standards Committee (CPSC) expert panel was to review the existing literature and establish recommendations about the use of MCS before, during, and after lung transplantation.MethodsThe AATS CPSC assembled an expert panel of 16 lung transplantation physicians who developed a consensus document of recommendations. The panel was broken into subgroups focused on preoperative, intraoperative, and postoperative support, and each subgroup performed a focused literature review. These subgroups formulated recommendation statements for each subtopic, which were evaluated by the entire group. The statements were then developed via discussion among the panel and refined until consensus was achieved on each statement.ResultsThe expert panel achieved consensus on 36 recommendations for how and when to use MCS in lung transplantation. These recommendations included the use of veno-venous extracorporeal membrane oxygenation (ECMO) as a bridging strategy in the preoperative setting, a preference for central veno-arterial ECMO over traditional cardiopulmonary bypass during the transplantation procedure, and the benefit of supporting selected patients with MCS postoperatively.ConclusionsAchieving optimal results in lung transplantation requires the use of a wide range of strategies. MCS provides an important mechanism for helping these critically ill patients through the peritransplantation period. Despite the complex nature of the decision making process in the treatment of these patients, the expert panel was able to achieve consensus on 36 recommendations. These recommendations should provide guidance for professionals involved in the care of end-stage lung disease patients considered for transplantation.  相似文献   
3.
认知障碍是指记忆、语言、理解和判断等一个或多个方面的功能障碍,包括轻度认知障碍和各种类型的痴呆症。痴呆症是认知障碍最严重的表现,是一种导致患者日常生活、社会交往和工作能力发生显著变化的综合征。阿尔茨海默病(AD)是最常见的痴呆症类型,其次是血管性痴呆(VD)和其他神经退行性痴呆[1]。已知年龄与认知功能的退化密切相关。  相似文献   
4.
目的 基于文本挖掘技术和生物医学数据库对新型冠状病毒肺炎(COVID-19)相关文献进行数据挖掘分析,探究COVID-19及其主要症状发热、咳嗽、呼吸障碍相关基因靶点,筛选潜在有效的化学药和中药。方法 使用GenCLiP 3网站获取COVID-19和其主要症状咳嗽、发热、呼吸障碍共4个关键词的共有靶点,在METASCAPE数据库中对其进行基因本体(GO)和通路富集分析,再利用String数据库和Cytoscape软件构建共有靶点的蛋白质相互作用网络,筛选获得核心基因,运用DGIdb数据库、SymMap数据库针对核心基因进行中西医治疗药物预测。结果 获得COVID-19及其主要症状共有基因靶点28个,其中有IL2、IL1B、CCL2等核心基因16个,使用DGIdb数据库筛选获得与16个关键靶点相互作用的化学药包括沙利度胺、来氟米特、环孢素等28种,中药包括虎杖、黄芪、芦荟等70味。结论 COVID-19及其主要症状的病理机制可能和CD4、KNG1、VEGFA等28个共有基因相关,可能通过介导TNF、IL-17等信号通路参与COVID-19病理过程。潜在有效药物可能通过作用相关靶点通路起到治疗COVID-19的作用。  相似文献   
5.
In this paper, we argue that understanding and addressing the problem of poor-quality medical products requires a more interdisciplinary approach than has been evident to date. While prospective studies based on rigorous standardized methodologies are the gold standard for measuring the prevalence of poor-quality medical products and understanding their distribution nationally and internationally, they should be complemented by social science research to unpack the complex set of social, economic, and governance factors that underlie these patterns. In the following sections, we discuss specific examples of prospective quality surveys and of social science studies, highlighting the value of cross-sector partnerships in driving high-quality, policy-relevant research in this area.  相似文献   
6.
目的 运用标准化患者法评估四川农村地区基层医生不稳定型心绞痛和2型糖尿病两种慢性病诊断准确性现状,探讨基层医生两种慢性病诊断准确性的主要影响因素,为提升基层医生两种慢性病诊断准确性提供科学依据。方法 采用多阶段随机整群抽样方法,抽取四川省自贡市5个区/县50个乡镇100个村为研究现场,以调查当日在岗的全科及内科医生作为研究对象。共进行两轮数据采集,第1轮采集样本乡镇卫生院和村卫生室医生的基本信息;第1轮调查完成1个月后,运用标准化患者法开展第2轮调查,收集农村基层医生对不稳定型心绞痛和2型糖尿病诊断结果信息。运用Logistic回归分析农村基层医生不稳定型心绞痛和2型糖尿病诊断准确性的影响因素。结果 共纳入172名农村基层医生,完成186次标准化患者访问,正确诊断率为48.39%。其中不稳定型心绞痛的正确诊断率为18.68%(17/91),2型糖尿病的正确诊断率为76.84%(73/95)。Logistic回归分析显示,具有执业医师资质的农村基层医生更有可能做出正确诊断(OR=4.857,95%CI=1.076~21.933,P=0.040)。农村基层医生在诊断过程中涉及的必要问诊和检查条目越多,做出正确诊断的概率越高(OR=1.627,95%CI=1.065~2.485,P=0.024)。与不稳定型心绞痛相比,农村基层医生对2型糖尿病做出正确诊断的可能性更高(OR=6.306,95%CI=3.611~11.013,P<0.001)。结论 四川农村基层医生不稳定型心绞痛和2型糖尿病诊断准确性整体较差,建议以基层医生慢性病诊断过程质量改善为突破口,提升基层医生执业水平,进而提高慢性病诊断准确性。  相似文献   
7.
温婷  刘汉娇  易云霞 《全科护理》2022,20(2):199-202
综述女性压力性尿失禁(stress urinary incontinence,SUI)风险预测的研究进展。指出女性SUI风险预测相关文献普遍存在风险预测工具和指标缺乏临床大样本验证,指标、纳入人群不统一的现象,风险预测模型存在构建过程未按报告规范进行,未进行完整的模型验证以及模型性能评价指标不规范的情况。未来研究可以在现有风险预测工具或模型的基础上进行改进、完善,以期为女性SUI风险预测提供参考。  相似文献   
8.
9.
目的比较飞秒激光制瓣准分子激光原位角膜磨镶术(FS-LASIK)、全飞秒激光小切口角膜基质透镜取出术(SMILE)和有晶状体眼后房型人工晶状体(ICL V4c)植入术三者矫正中低度近视的效果。方法采用回顾性研究。以惠州爱尔眼科医院2019年6月至2020年4月矫正中低度近视120例(120眼)作为研究对象,受术者分为FS-LASIK组、SMILE组及ICL组,每组40例(40眼),各组分别接受相应的手术,术后随访3个月比较其矫正效果。结果术后1个月及3个月,3组间视力及有效性指数对比差异无统计学意义(P>0.05);ICL组安全性指数高于SMILE组及FS-LASIK组(P<0.05)。术后3个月FS-LASIK组的三叶草像差、彗差和球差出现明显变化,而SMILE组的变化较小,ICL组变化最小(P<0.05)。结论对中低度近视FS-LASK、SMILE及ICL植入术三者均有确切疗效,而ICL V4c植入术的安全性最高,患者的视觉质量最好。  相似文献   
10.
ObjectiveNew-onset postoperative atrial fibrillation (POAF) after cardiac surgery is common, with rates up to 60%. POAF has been associated with early and late stroke, but its association with other cardiovascular outcomes is less known. The objective was to perform a meta-analysis of the studies reporting the association of POAF with perioperative and long-term outcomes in patients with cardiac surgery.MethodsWe performed a systematic review and a meta-analysis of studies that presented outcomes for cardiac surgery on the basis of the presence or absence of POAF. MEDLINE, EMBASE, and the Cochrane Library were assessed; 57 studies (246,340 patients) were selected. Perioperative mortality was the primary outcome. Inverse variance method and random model were performed. Leave-one-out analysis, subgroup analyses, and metaregression were conducted.ResultsPOAF was associated with perioperative mortality (odds ratio [OR], 1.92; 95% confidence interval [CI], 1.58-2.33), perioperative stroke (OR, 2.17; 95% CI, 1.90-2.49), perioperative myocardial infarction (OR, 1.28; 95% CI, 1.06-1.54), perioperative acute renal failure (OR, 2.74; 95% CI, 2.42-3.11), hospital (standardized mean difference, 0.80; 95% CI, 0.53-1.07) and intensive care unit stay (standardized mean difference, 0.55; 95% CI, 0.24-0.86), long-term mortality (incidence rate ratio [IRR], 1.54; 95% CI, 1.40-1.69), long-term stroke (IRR, 1.33; 95% CI, 1.21-1.46), and longstanding persistent atrial fibrillation (IRR, 4.73; 95% CI, 3.36-6.66).ConclusionsThe results suggest that POAF after cardiac surgery is associated with an increased occurrence of most short- and long-term cardiovascular adverse events. However, the causality of this association remains to be established.  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