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   44042篇
  免费   3681篇
  国内免费   755篇
耳鼻咽喉   93篇
儿科学   1065篇
妇产科学   1333篇
基础医学   3161篇
口腔科学   207篇
临床医学   11134篇
内科学   9612篇
皮肤病学   331篇
神经病学   1222篇
特种医学   2410篇
外国民族医学   6篇
外科学   5261篇
综合类   6220篇
现状与发展   3篇
预防医学   1617篇
眼科学   441篇
药学   2327篇
  52篇
中国医学   524篇
肿瘤学   1459篇
  2023年   749篇
  2022年   1230篇
  2021年   1779篇
  2020年   2081篇
  2019年   1988篇
  2018年   1960篇
  2017年   1791篇
  2016年   1694篇
  2015年   1860篇
  2014年   3525篇
  2013年   3151篇
  2012年   2367篇
  2011年   2637篇
  2010年   2118篇
  2009年   2064篇
  2008年   2155篇
  2007年   2102篇
  2006年   1810篇
  2005年   1429篇
  2004年   1203篇
  2003年   1067篇
  2002年   857篇
  2001年   691篇
  2000年   604篇
  1999年   560篇
  1998年   422篇
  1997年   429篇
  1996年   401篇
  1995年   358篇
  1994年   336篇
  1993年   292篇
  1992年   245篇
  1991年   224篇
  1990年   186篇
  1989年   152篇
  1988年   176篇
  1987年   138篇
  1986年   126篇
  1985年   200篇
  1984年   217篇
  1983年   105篇
  1982年   145篇
  1981年   118篇
  1980年   120篇
  1979年   97篇
  1978年   67篇
  1977年   76篇
  1976年   81篇
  1975年   71篇
  1974年   59篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
1.
2.
目的探讨多元化联合教学模式在超声引导下疼痛介入治疗教学中的应用效果。方法选择2018年1月至2020年12月在北京大学第三医院疼痛科进修的30名医师作为研究对象,将其分为对照组与观察组;对照组采用常规教学模式;观察组采用多元化联合教学模式,比较两组医师技能考核成绩、教学质量评分和满意度评分。结果观察组医师技能考核成绩优良率为93.3%,高于对照组的73.3%(P<0.05);观察组医师对基础理论知识掌握、临床思维能力的提高、学习兴趣的激发、疾病诊治能力的提高4个方面的评分均高于对照组(P<0.01)。结论多元化联合教学模式可促进超声引导下疼痛介入治疗技能的提高,有利于提高学员的综合临床能力。  相似文献   
3.
4.
PurposeTo evaluate the effectiveness and safety of fluoroscopy-guided percutaneous high ligation (FPHL) combined with fluoroscopy-guided foam sclerotherapy (FGFS) to treat varicose veins of the great saphenous veins (GSVs).Materials and MethodsThis was a retrospective study of 113 patients (mean age, 62.1 ± 10.8 years; 60 men) with varicose veins of the GSVs (133 limbs) that were treated with FPHL combined with FGFS between April 1 and October 31, 2019. Demographic and clinical data were collected from these patients before the FPHL procedure, after which FGFS was performed. The preterminal GSV was ligated percutaneously by a percutaneously-positioned polypropylene ligature under fluoroscopic guidance. The outcome of ligation was confirmed by venography. Then, foam sclerotherapy was performed under fluoroscopy. At 1-year follow-up, GSV occlusion was evaluated by ultrasound. The venous clinical severity scores (VCSSs) were compared between the preoperative and 1-year follow-up periods.ResultsThe technical success rate was 100% (133 limbs). Complete 12-month follow-up was available for 112 limbs (84.2%) and 103 of these limbs (92.0%) remained occluded during this period. The VCSS improved from 4.71 ± 2.15 to 0.74 ± 0.60 (V = 6328, P < .001). During follow-up, there were 16 limbs with thrombophlebitis and 38 limbs with saphenous junction pain; these events were alleviated within 2 weeks of the procedure. There was no deep venous thrombosis or other severe adverse events.ConclusionsFPHL combined with FGFS to treat varicose veins in the GSVs achieved an occlusion rate of 92% and improved the clinical symptoms within 1 year; this minimally-invasive procedure was safe and effective.  相似文献   
5.
6.
A male in his 90 s consulted a doctor because he experienced several days of general fatigue and dyspnea. He was diagnosed with heart failure, and diuretic medications taken for 3 days relieved his symptoms. However, he was found dead on the morning of the fourth day after consultation. He had received a third dose of coronavirus disease 2019 (COVID-19) vaccine approximately 2 weeks before death. An autopsy revealed dissection of the ascending aorta and pericardial hemotamponade. The heart showed a white villous surface, and the pericardium was fibrously thick. Microscopic examination revealed pericarditis with predominantly macrophage and lymphocyte infiltration. These histological findings were compatible with those of post-vaccination myocarditis. To the best of our knowledge, histopathologically proven pericarditis after COVID-19 vaccination has not been reported. In the present case, extended inflammation of the aortic adventitia was a possible cause of aortic wall fragility followed by dissection.  相似文献   
7.
PurposeAnaerobic infections are common yet life-threatening. They are being recovered from all sites of the body, including the cardiovascular system. This study was aimed to determine the retrospective analysis on the isolation of anaerobes in cardiovascular samples received for a decade-long duration. It helps in knowing the frequency of isolation of anaerobic causes of cardiovascular infection.MethodsAll cardiovascular samples from the department of Cardio-thoracic vascular surgery from January 2010 to December 2020 were studied.ResultsOf 601 samples received, predominant samples were vegetations and valvular tissues of 258, followed by 98 samples of pericardial tissues, 92 samples of embolus, 90 samples of blood and post-operative collections, and 63 excised aneurysms and vascular grafts. Of the total, 15 samples grew anaerobes where Clostridium species were the predominant isolates. Clostridioides difficile was isolated in 2 samples.ConclusionsAnaerobes in cardiovascular samples are uncommon yet form a significant cause of morbidity and mortality. Most infections are from the contiguous spread, penetrating trauma, and hematogenous causing endocarditis or valvular infections. These conditions and samples form the seat of infectious focus and clinical suspicion towards the anaerobic cause of these conditions, especially in conventional routine culture-negative samples. Timely diagnosis of anaerobic infections plays a vital role in the good prognostic outcome of patients undergoing cardiothoracic and vascular surgery.  相似文献   
8.
PurposeTo evaluate temporal trends, practice variation, and associated outcomes with the use of intravascular ultrasound (US) during deep venous stent placement among Medicare beneficiaries.Materials and MethodsAll lower extremity deep venous stent placement procedures performed between January 1, 2017, and December 31, 2019 among Medicare beneficiaries were included. Temporal trends in intravascular US use were stratified by procedural setting and physician specialty. The primary outcome was a composite of 12-month all-cause mortality, all-cause hospitalization, or repeat target vessel intervention. The secondary outcome was a composite of 12-month stent thrombosis, embolization, or restenosis.ResultsAmong the 20,984 deep venous interventions performed during the study period, 15,184 (72.4%) utilized intravascular US. Moderate growth in intravascular US use was observed during the study period in all clinical settings. There was a variation in the use of intravascular US among all operators (median, 77.3% of cases; interquartile range, 20.0%–99.2%). In weighted analyses, intravascular US use during deep venous stent placement was associated with a lower risk of both the primary (adjusted hazard ratio, 0.72; 95% confidence interval [CI], 0.69–0.76; P < .001) and secondary (adjusted hazard ratio, 0.32; 95% CI, 0.27–0.39; P < .001) composite end points.ConclusionsIntravascular US is frequently used during deep venous stent placement among Medicare beneficiaries, with further increase in use from 2017 to 2019. The utilization of intravascular US as part of a procedural strategy was associated with a lower cumulative incidence of adverse outcomes after the procedure, including venous stent thrombosis and embolization.  相似文献   
9.
10.
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