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   63396篇
  免费   6019篇
  国内免费   2462篇
耳鼻咽喉   544篇
儿科学   972篇
妇产科学   788篇
基础医学   7057篇
口腔科学   1494篇
临床医学   6023篇
内科学   10028篇
皮肤病学   606篇
神经病学   4299篇
特种医学   1837篇
外国民族医学   1篇
外科学   5168篇
综合类   10565篇
现状与发展   4篇
一般理论   2篇
预防医学   9335篇
眼科学   1072篇
药学   5806篇
  77篇
中国医学   3693篇
肿瘤学   2506篇
  2024年   207篇
  2023年   1346篇
  2022年   2232篇
  2021年   3476篇
  2020年   3100篇
  2019年   2418篇
  2018年   2332篇
  2017年   2409篇
  2016年   2387篇
  2015年   2532篇
  2014年   4331篇
  2013年   4915篇
  2012年   3809篇
  2011年   4346篇
  2010年   3390篇
  2009年   3355篇
  2008年   3301篇
  2007年   3192篇
  2006年   2645篇
  2005年   2368篇
  2004年   1893篇
  2003年   1730篇
  2002年   1282篇
  2001年   1140篇
  2000年   1009篇
  1999年   850篇
  1998年   653篇
  1997年   630篇
  1996年   524篇
  1995年   464篇
  1994年   449篇
  1993年   335篇
  1992年   325篇
  1991年   253篇
  1990年   254篇
  1989年   204篇
  1988年   172篇
  1987年   180篇
  1986年   133篇
  1985年   197篇
  1984年   170篇
  1983年   113篇
  1982年   114篇
  1981年   115篇
  1980年   121篇
  1979年   100篇
  1978年   66篇
  1977年   52篇
  1976年   56篇
  1973年   43篇
排序方式: 共有10000条查询结果,搜索用时 616 毫秒
41.
舌癌患者手术及放化疗后会出现构音障碍、吞咽困难、口腔黏膜炎、口干、营养不良等并发症,使患者生存质量下降,甚至导致肿瘤的复发转移,影响生存期,单一方法往往顾此失彼。依托于中国中医科学院西苑医院肿瘤康复基地,杨宇飞教授在国内外调研考察基础上,结合中国国情,构建了一种“门诊多学科肿瘤康复模式”,在舌癌康复方面,以患者为中心,以中医肿瘤内科为主导,多学科共同参与,结合康复科、口腔科、营养科、药剂科等各科优势,形成全程个体化规范序贯康复方案,对患者及早进行康复,在放疗前进行预防性干预尤其重要,使患者能够快速缓解手术和放疗的不良反应,患者获益明显。现取两个典型案例总结其舌癌多学科康复的经验,以期为舌癌的康复提供借鉴。  相似文献   
42.
目的 探讨以行为-结构化-关系(BSR)干预模式对短期住院孤独症谱系障碍(ASD)儿童的干预疗效,为改善ASD儿童的预后提供参考依据。方法 选取2015年12月-2016年12月确诊为ASD的2~6岁儿童141例,随机分为治疗组和对照组。治疗组ASD儿童均接受BSR模式的短期课程训练,训练课程包括个别辅导、游戏课、运动课、音乐课等,每天训练时间6 h,持续1个月;对照组ASD儿童处于干预等待,接受随访观察和评估。所有ASD儿童干预前、后均接受儿童心理教育评估(第三版)(PEP-3)来进行各方面能力变化的评估。结果 治疗组、对照组干预前各副测验的原积分差异无统计学意义(P>0.05)。两组ASD儿童干预后认知、语言理解、模仿、情感表达、社会互动、行为特征-非语言、适应行为的原积分比较,差异均有统计学意义(t=2.41、2.02、4.14、3.69、4.42、2.69、2.96,P<0.05);但小肌肉、大肌肉、自理的原积分比较,差异无统计学意义(t=-1.13、-1.05、-0.84,P>0.05)。结论 BSR干预模式能够有效改善短期住院ASD儿童的预后,可推广用于儿童ASD的治疗。  相似文献   
43.
IntroductionDifferent muscular activities of the quadriceps components for producing necessary torque may change in patients with patellofemoral pain syndrome (PFPS). The aim of the current study, therefore, was to assess the contribution of each component of the quadriceps femoris muscle for producing external torque in patients with PFPS.MethodTwelve females with PFPS (24.7 ± 2.3 years) and twelve healthy matched females (25.4 ± 2.4 years) performed three consecutive knee flexion and extension movements with maximum effort at 45°/s and 300°/s using a Biodex system 3 dynamometer. Simultaneously, electromyographic (EMG) activities of the vastus medialis oblique (VMO), RF (rectus femoris) and vastus lateralis (VL) muscles were recorded using a DataLog instrument. Standard multiple regressions were used to assess the ability of EMG activities of the VMO, RF and VL muscles to predict normalized quadriceps femoris isokinetic concentric and eccentric torques at 45°/s and 300°/s in the normal and patient groups.ResultsIn the normal group, the VL and the VMO were the good predictors of quadriceps concentric torque at 45°/s and 300°/s, respectively. The VL and the RF were the good predictors of quadriceps eccentric torque at 300°/s in the patient group. No other conditions showed a considerable prediction for quadriceps torque in the normal or patient group.ConclusionFemales with PFPS differ with normal females in terms of the contribution of each component of the quadriceps femoris for producing external torque. Training the VMO for concentric contraction at both high and low velocities should be included in the management of the patients with PFPS.  相似文献   
44.
45.
46.
BackgroundUnequal housing access resulted in more than 150 million homeless people worldwide, with millions more expected to be added every year due to the ongoing climate-related crises. Homeless population has a counterproductive effect on the social, psychological integration efforts by the community and exposure to other severe health-related issues. Geographic Information Systems (GIS) have long been applied in urban planning and policy, housing and homelessness, and health-related research.MethodsWe used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method to systematically review 24 articles collected from multiple databases (n = 10) that focused on health-related issues among homeless people and used geospatial analysis techniques in their research.ResultsOur findings indicated a geographic clustering of case study locations– 26 out of the 31 case study sites are from the USA and Canada. Studies used spatial analysis techniques to identify hotspots, clusters and patterns of patient location and population distribution. Studies also reported relationships among the location of homeless shelters and substance use, discarded needles, different infectious and non-infectious disease clusters.ConclusionMost studies were restricted in analyzing and visualizing the patterns and disease clusters; however, geospatial analyses techniques are useful and offer diverse techniques for a more sophisticated understanding of the spatial characteristics of the health issues among homeless people. Better integration of GIS in health research among the homeless would help formulate sensible policies to counter health inequities among this vulnerable population group.  相似文献   
47.
BackgroundParkinson’s disease (PD) is a chronic and progressive neurodegenerative disease with no cure, presenting a challenging diagnosis and management. However, despite a significant number of criteria and guidelines have been proposed to improve the diagnosis of PD and to determine the PD stage, the gold standard for diagnosis and symptoms monitoring of PD is still mainly based on clinical evaluation, which includes several subjective factors. The use of machine learning (ML) algorithms in spatial-temporal gait parameters is an interesting advance with easy interpretation and objective factors that may assist in PD diagnostic and follow up.Research questionThis article studies ML algorithms for: i) distinguish people with PD vs. matched-healthy individuals; and ii) to discriminate PD stages, based on selected spatial-temporal parameters, including variability and asymmetry.MethodsGait data acquired from 63 people with PD with different levels of PD motor symptoms severity, and 63 matched-control group individuals, during self-selected walking speed, was study in the experiments.ResultsIn the PD diagnosis, a classification accuracy of 84.6 %, with a precision of 0.923 and a recall of 0.800, was achieved by the Naïve Bayes algorithm. We found four significant gait features in PD diagnosis: step length, velocity and width, and step width variability. As to the PD stage identification, the Random Forest outperformed the other studied ML algorithms, by reaching an Area Under the ROC curve of 0.786. We found two relevant gait features in identifying the PD stage: stride width variability and step double support time variability.SignificanceThe results showed that the studied ML algorithms have potential both to PD diagnosis and stage identification by analysing gait parameters.  相似文献   
48.
49.
目的 前房注射卡波姆建立大鼠高眼压模型,观察卡波姆升眼压效果及对大鼠眼前节和视网膜的影响。方法 随机选取30只SD大鼠,注射前3 d早晚测量基线眼压。右眼定为实验眼,左眼定为对照眼,右眼放出房水后将30 μL的5 g·L-1卡波姆混悬液注入前房,每日早10时、晚22时在大鼠清醒状态下测量眼压。每周进行双眼眼前节照相并对比。4周末处死26只大鼠(另4只持续观察眼压变化至注射后9周)并取双眼眼球行HE染色,观察实验眼与对照眼视网膜形态,对比视网膜厚度及房角形态。结果 注射前,实验眼白天和夜间眼压分别为(11.10±0.90)mmHg(1 kPa=7.5 mmHg)和(11.92±1.07)mmHg,对照眼分别为(11.22±1.07)mmHg和(11.76±1.08)mmHg;实验眼与对照眼相比,白天、夜间眼压差异均无统计学意义(均为 P>0.05);白天与夜间眼压相比,实验眼、对照眼差异均有统计学意义(均为P<0.05)。卡波姆在前房中呈现出弥散型和沉积型两种存在方式,弥散型和沉积型大鼠1周内眼压分别为(17.83±3.54)mmHg和(13.00±1.55)mmHg,两者相比差异具有统计学意义(P<0.05)。注射后第1天至第19天,实验眼与对照眼白天眼压相比差异均具有统计学意义(均为P<0.05);注射后第1天至第27天,实验眼与对照眼夜间眼压相比差异均具有统计学意义(均为P<0.05)。实验眼视网膜形态发生改变,注射后4周视网膜厚度为(254.70±21.80)μm,与对照眼的(346.73±24.63)μm相比,差异有统计学意义(P=0.00)。实验眼前房充满卡波姆及虹膜的混合成分,紧贴角膜内皮并延伸至房角,堵塞小梁网结构,正常虹膜形态消失;对照眼房角形态正常。结论 前房注射卡波姆建立大鼠高眼压模型,可维持高眼压4周以上,昼夜眼压差异较为明显,夜间眼压较白天更高,4周后视网膜出现高眼压损伤后的表现。  相似文献   
50.
BackgroundCoronary artery bypass grafting (CABG) improves survival in patients with heart failure and severely reduced left ventricular systolic function (LVEF). Limited data exist regarding adverse cardiovascular event rates after CABG in patients with heart failure with midrange ejection fraction (HFmrEF; LVEF > 40% and < 55%).MethodsWe analyzed data on isolated CABG patients from the Veterans Affairs national database (2010-2019). We stratified patients into control (normal LVEF and no heart failure), HFmrEF, and heart failure with reduced LVEF (HFrEF) groups. We compared all-cause mortality and heart failure hospitalization rates between groups with a Cox model and recurrent events analysis, respectively.ResultsIn 6533 veterans, HFmrEF and HFrEF was present in 1715 (26.3%) and 566 (8.6%) respectively; the control group had 4252 (65.1%) patients. HFrEF patients were more likely to have diabetes mellitus (59%), insulin therapy (36%), and previous myocardial infarction (31%). Anemia was more prevalent in patients with HFrEF (49%) as was a lower serum albumin (mean, 3.6 mg/dL). Compared with the control group, a higher risk of death was observed in the HFmrEF (hazard ratio [HR], 1.3 [1.2-1.5)] and HFrEF (HR, 1.5 [1.2-1.7]) groups. HFmrEF patients had the higher risk of myocardial infarction (subdistribution HR, 1.2 [1-1.6]; P = .04). Risk of heart failure hospitalization was higher in patients with HFmrEF (HR, 4.1 [3.5-4.7]) and patients with HFrEF (HR, 7.2 [6.2-8.5]).ConclusionsHeart failure with midrange ejection fraction negatively affects survival after CABG. These patients also experience higher rates myocardial infarction and heart failure hospitalization.  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