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   10975篇
  免费   1237篇
  国内免费   185篇
耳鼻咽喉   79篇
儿科学   120篇
妇产科学   23篇
基础医学   1103篇
口腔科学   61篇
临床医学   1267篇
内科学   910篇
皮肤病学   71篇
神经病学   1196篇
特种医学   538篇
外科学   402篇
综合类   1050篇
预防医学   348篇
眼科学   3992篇
药学   815篇
  2篇
中国医学   285篇
肿瘤学   135篇
  2024年   33篇
  2023年   231篇
  2022年   329篇
  2021年   584篇
  2020年   559篇
  2019年   433篇
  2018年   494篇
  2017年   513篇
  2016年   477篇
  2015年   499篇
  2014年   741篇
  2013年   877篇
  2012年   675篇
  2011年   643篇
  2010年   538篇
  2009年   541篇
  2008年   462篇
  2007年   424篇
  2006年   436篇
  2005年   374篇
  2004年   323篇
  2003年   245篇
  2002年   226篇
  2001年   199篇
  2000年   162篇
  1999年   101篇
  1998年   118篇
  1997年   105篇
  1996年   83篇
  1995年   79篇
  1994年   63篇
  1993年   54篇
  1992年   65篇
  1991年   46篇
  1990年   46篇
  1989年   48篇
  1988年   41篇
  1987年   38篇
  1986年   38篇
  1985年   70篇
  1984年   62篇
  1983年   51篇
  1982年   56篇
  1981年   60篇
  1980年   45篇
  1979年   30篇
  1978年   26篇
  1977年   15篇
  1976年   13篇
  1973年   6篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
81.
ABSTRACT

Purpose

The aim of the present study was to assess the association between levels of physical activity (PA) and the presence of cataracts in people aged 15–69 years residing in Spain.  相似文献   
82.
83.
《The ocular surface》2020,18(1):108-113
PurposeAromatase inhibitors (AIs) limit the synthesis of oestrogen in peripheral tissues thus lowering levels of oestrogen. The primary aim was to evaluate whether women treated with AIs have altered dry eye symptoms and signs. A sub-aim was to investigate whether symptoms of dry eye in postmenopausal women were associated with symptoms of non-eye pain, ocular pain and self-rated pain perception.MethodsThis cross-sectional, observational, single visit study recruited 56 postmenopausal women (mean age 64.1 + 7.9 years) and 52 undergoing AI treatment (mean age 66.6 + 9.0). Ocular symptoms (OSDI, MGD14) and pain questionnaires (PSQ, OPAS) were administered and signs of dry eye and meibomian gland dysfunction were evaluated.ResultsAlmost half of each group reported dry eye symptoms, defined as OSDI>12 (48% control, 46% AI). The PSQ score was significantly higher in the AI group (p = 0.04). Neither frequency or severity of dry eye (or MGD) symptoms scores were significantly different between groups. In the AI group, meibomian gland expressibility score was worse (p = 0.003); there were no differences in any other signs. Higher OSDI scores were associated with higher OPAS eye-pain scores (r = 0.49, p < 0.001), but not OPAS non-eye pain (r = 0.09, p = 0.35). Pain perception (PSQ) showed a moderate positive association with OPAS eye-pain (r = 0.30, p = 0.003).ConclusionsIn this study elevated ocular symptoms were observed in both the AI treated and the untreated groups, with no difference between the groups. Women undergoing AI treatment for early stage breast cancer had worse meibum expressibility score and increased pain perception compared to an untreated group of women.  相似文献   
84.
ObjectiveTo propose the Intense Pulsed Light (IPL) therapy as a helpful supplementary treatment in patients with dry eye disease.Material and methodsRetrospective cross sectional design. Medical records of patients in whom dry eye disease symptoms were not satisfactorily controlled with medical therapy alone and who underwent additional IPL with at least three sessions completed. Data were analyzed before therapy and 3 weeks after its completion to asses improvement. Determination of symptoms, through a visual analog scale; tear film stability, through tear Break Up Time (tBUT); measurement of tear secretion, through Schirmer Test; and ocular surface staining with Van Bijsterveld score were evaluated. SPSS software and nonparametric analysis of repeated measures were used. The study was approved by the ethics committee.Results50 eyes from 25 subjects were reviewed. There were 9 males (36%) and 16 females (64%), with a median age of 59 years (IQR 52-64). The median of the symptoms scale was 8 (IQR 8-9) and 3 (IQR 2-4) before and after the therapy respectively (P < .05). The median of BUT was 4 (IQR 3-5) and 10 (IQR 8-11), Schirmer test was 13 (IQR 12-15) and 15 (IQR 13-20), and Van Bijsterveld score was 3 (RIC 3-4) and 2 (IQR 2-3) before and after the therapy respectively (P < .05, for all measurements).ConclusionIPL treatment has excellent results regarding both: dry eye disease symptoms improvement and in office objective tests such as tBUT, Schirmer test and Van Bijsterveld score; IPL could be considered as an effective adjunct for dry eye disease.  相似文献   
85.
目的:探究中药熏蒸联合人工泪液治疗干眼症的临床疗效,分析其对患者视觉相关生命质量的影响。方法:选取2014年11月至2016年12月北京市健宫医院收治的干眼症患者72例作为研究对象,按照随机数字表法随机分为对照组和观察组,每组36例(72只患眼),对照组给予人工泪液治疗,观察组在对照组的基础上联合中药熏蒸治疗,2周为1个疗程,2组均连续治疗2个疗程。统计2组临床疗效;比较2组患者治疗前后主要中医症状积分、泪液分泌量、泪膜破裂时间;采用美国国家眼科研究所视觉相关生命质量量表(NEI-VFQ-25)评价并比较2组患者治疗前后视觉相关生命质量。结果:治疗后观察组总有效率为90. 28%,较对照组的63. 89%显著升高(P 0. 01);与治疗前比较,治疗后2组患者患眼疲劳感、干涩感、异物感及烧灼感等症状积分均显著降低,且观察组显著低于对照组(P 0. 01);与治疗前比较,治疗2周后至治疗4周后2组泪液分泌量呈逐渐升高趋势(P 0. 01),泪膜破裂时间呈逐渐延长趋势(P 0. 05),且治疗后2组间差异有统计学意义(P 0. 05或P 0. 01);与治疗前比较,治疗后2组患眼一般健康状况、活动障碍及视力障碍评分均显著升高(P 0. 01),且观察组显著高于对照组(P 0. 01)。结论:中药熏蒸联合人工泪液治疗干眼症可有效缓解患眼临床症状,促进患眼泪液分泌并增强泪膜稳定性,同时还可显著改善患眼视觉相关生命质量,疗效显著优于人工泪液单用。  相似文献   
86.
本文主要介绍了精神科用医用眼动仪的发展历程。阐述了眼电法眼动仪、角膜反光法眼动仪以及瞳孔-角膜反射向量法医用眼动仪的工作原理和眼动仪在精神分裂症诊断方面的临床应用效果,介绍了国内外眼动仪研究现状,且结合实际工作提出了未来医用眼动仪的设计发展趋势。  相似文献   
87.
背景与目的:应用二维斑点追踪成像(two-dimensional speckle tracking imaging,2D-STI)结合心肌做功评价蒽环类药物对乳腺癌患者左心室功能的影响。方法:前瞻性选择2019年9月—2020年3月在复旦大学附属肿瘤医院行蒽环类药物治疗的35例乳腺癌患者,分别于化疗前、化疗2个周期后、4个周期后行常规超声心动图检查并获取动态二维图像,同时使用肱动脉袖带血压计测量患者收缩期及舒张期血压值,测量左房内径(left atrial diameter,LAD)、左心室舒张末期内径(left ventricular end-diastolic diameter,LVEDD)、左心室收缩末期内径(left ventricular end-systolic diameter,LVESD)、舒张末期室间隔厚度(diastolic interventricular septal depth,IVSD)、左心室舒张末期容积(left ventricular end-diastolic volume,LVEDV)、左心室收缩末期容积(left ventricular end-systolic volume,LVESV)、左心室射血分数(left ventricular ejection fraction,LVEF)、二尖瓣口舒张早期峰值流速(early diastolic peak velocity,E峰)、舒张晚期峰值流速(late diastolic tissue velocity,A峰)、二尖瓣环间隔处舒张早期峰值速度(early diastolic tissue velocity,e’),并计算E/A、E/e’;应用EchoPac软件脱机分析,获取左心室整体纵向应变(global longitudinal strain,GLS)、左心室分层纵向应变(GLSendo、GLSmid、GLSepi),以及左心室心肌整体做功指数(global myocardial work index,GWI)、整体有用功(global constructive work,GCW)、整体无用功(global wasted work,GWW)、整体做功效率(global myocardial work efficiency,GWE);并行统计学分析。结果:与化疗前比较,化疗2个周期乳腺癌患者GLSeondo、GLS有所减低,但差异无统计学意义(P>0.05);GWW增加,GWE降低(P<0.05);化疗4个周期后GLS、GLSendo、GWI、GCW、GWE均降低,GWW增加。与化疗2个周期后比较,化疗4个周期后乳腺癌患者GLS、GLSendo、GWI、GCW、GWE降低,GWW增加(P<0.05)。与化疗前比较,化疗4个周期后乳腺癌患者E/e’升高(P<0.05)。各周期结束后的其余各项超声心动图参数与化疗前比较差异均无统计学意义(P>0.05)。结论:2D-STI能早期检测乳腺癌患者在蒽环类药物化疗中左心室功能的早期改变, GWW及GWE较其他参数更敏感。  相似文献   
88.
89.
90.
BackgroundSocial interaction at its core entails allocating attention to relevant stimuli. As such, the perception of change requires attention, but studies have suggested that the social impairment in people with autism spectrum disorder (ASD) occurs at the attentual level of "on-line" social cognition.MethodForty-four young adults—22 with autism spectrum disorder (ASD) and 22 with typical development (TD)—participated in two experiments. The first used a change blindness (CB) paradigm where attention was investigated through the detection of changed items with central and marginal levels of interest when viewing images of everyday scenarios. Eye-tracking was used to compare response times, first fixations and total fixation time on changes. The second used social films with eye tracking of gaze fixations.ResultsParticipants with ASD were slower in response time and first fixation than were participants with TD. Participants with TD showed longer fixation on items with marginal (compared to central) levels of interest. The social-film experiment showed that participants with ASD were slower to orient their gazes towards the characters’ faces and looked at speaking characters for less time than did the group with TD. This result correlates with less use of mental verbs in their narratives and less time spent looking at marginal items in the CB experiment.ConclusionsResults suggest reduced processing speed in young adults with ASD, which is associated with enhanced processing of local details. Clinically, these results imply that teaching strategies (e.g., cognitive cues) to process social context efficiently could benefit individuals with ASD.  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