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   4244篇
  免费   236篇
  国内免费   11篇
耳鼻咽喉   49篇
儿科学   144篇
妇产科学   30篇
基础医学   524篇
口腔科学   119篇
临床医学   289篇
内科学   892篇
皮肤病学   58篇
神经病学   507篇
特种医学   207篇
外科学   641篇
综合类   94篇
预防医学   216篇
眼科学   72篇
药学   331篇
中国医学   6篇
肿瘤学   312篇
  2023年   34篇
  2022年   25篇
  2021年   99篇
  2020年   54篇
  2019年   89篇
  2018年   118篇
  2017年   87篇
  2016年   88篇
  2015年   111篇
  2014年   155篇
  2013年   217篇
  2012年   291篇
  2011年   305篇
  2010年   155篇
  2009年   157篇
  2008年   225篇
  2007年   234篇
  2006年   244篇
  2005年   209篇
  2004年   190篇
  2003年   184篇
  2002年   144篇
  2001年   113篇
  2000年   100篇
  1999年   84篇
  1998年   50篇
  1997年   53篇
  1996年   42篇
  1995年   25篇
  1994年   33篇
  1993年   38篇
  1992年   56篇
  1991年   59篇
  1990年   40篇
  1989年   38篇
  1988年   32篇
  1987年   39篇
  1986年   34篇
  1985年   31篇
  1984年   26篇
  1983年   19篇
  1982年   10篇
  1981年   14篇
  1980年   16篇
  1979年   8篇
  1978年   15篇
  1977年   8篇
  1976年   7篇
  1975年   14篇
  1967年   6篇
排序方式: 共有4491条查询结果,搜索用时 31 毫秒
61.
Acinetobacter baumannii is emerging as a major cause of nosocomial infections particularly in high risk patients. Being resistant to adverse environmental conditions, it can stay for prolonged periods in the hospital environment. We report an outbreak in the medical oncology ward where nine patients suspected of bacteraemia were blood culture positive forA. baumannii from the two samples each, one collected through the i.v. cannula and another through the peripheral venous puncture. The bacteria was also isolated from the environmental sources from the various samples collected. The biotype, antibiogram, cellular protein profiles on SDS-PAGE and the restriction enzyme analysis patterns of the patient isolates and the environmental isolates were similar. This points to the environment as a source of infection. With reinforcement of proper barrier nursing and use of disposable heparine ampoules it was possible to control the outbreak.  相似文献   
62.
Objective. To review imaging studies of isolated involvement of the sacrum due to tuberculosis and determine the role of imaging in the diagnosis and management of these patients. Design and patients. A retrospective analysis of 15 cases of isolated sacral tuberculosis imaged with MR imaging was performed. The CT images were also reviewed where available, and the various lesion characteristics were identified. We also reviewed the medical records in an attempt to determine the impact of the imaging studies on the management of these patients. Results. Fifteen patients (5 male, 10 female) presented with symptoms of 3–15 months’ duration. Chronic localized backache with muscle spasm was the commonest presenting symptom; discharging sinuses with abscess formation was found in six patients, five of whom were children. MR imaging of the sacrum revealed a hypointense marrow signal on T1-weighted images and hyperintense signal on T2-weighted images in 14 of 15 patients, the S2 vertebra being always involved. CT revealed osteolytic changes in the sacrum in all the five patients in whom CT was performed. All patients showed marked clinical improvement within 1 year of anti-tuberculous chemotherapy. Conclusion. Isolated tuberculosis of the sacrum is uncommon but should be suspected in patients presenting with chronic low backache or children with discharging sinuses/abscesses and showing sacral destruction on CT or MR imaging. MR imaging can identify cases and enables early institution of anti- tuberculous chemotherapy. Received: 31 August 1999 Revision requested: 1 November 1999 Revision received: 27 March 2000 Accepted: 14 April 2000  相似文献   
63.
64.
65.
背景:银屑病对患者心理和情绪影响很大。依那西普治疗银屑病患者临床症状有效,作者评估了该药对银屑病相关疲劳和抑郁症状的疗效。方法:618例中至重度银屑病患者接受安慰剂或依那西普50mg(2次/周)双盲治疗。主要疗效终点:治疗12周时,银屑病面积和严重度指数评分较基线改善达75%(PASI 75)或更高水平;次要和其他疗效终点:慢性病治疗疲劳功能评估(FACIT-F)分级、Hamilton抑郁量表(Ham-D)分级、Beck抑郁列表(BDI)及不良事件。根据分组治疗进行疗效分析。基于实际接受治疗的情况对安全性资料进行分析和总结。  相似文献   
66.
67.
Remission of depressive symptoms is the goal of all antidepressant therapy. Rating scales define remission in clinical trials, but it is unclear how well these definitions predict risk of later relapse. We measured the sensitivity and specificity of a range of Montgomery-Asberg Depression Rating Scale (MADRS) cutoff scores at 3- and 6-months, wherein scores above a given cutoff would predict relapse over an 18-month period. We examined 153 elderly depressed subjects exhibiting a MADRS < or = 15 after 3 or 6 months of antidepressant therapy. Subjects who subsequently exhibited a MADRS > 15 during the 18-month study period were defined as relapsed. Receiver operating characteristic (ROC) curves were developed and area under the curve (AUC) values calculated for the sensitivity and specificity of 3- and 6-month MADRS scores to predict future relapse. The 3-month ROC had an AUC value of 0.63; the 6-month ROC had an AUC value of 0.66. There was no MADRS cutoff found that could predict likelihood of relapse with good sensitivity and specificity. A post hoc analysis where relapse rate was adjusted by controlling for medical comorbidity, disability, and social support showed no change in the ROCs or AUC values. The higher the MADRS score at 3 and 6 months, the greater the likelihood of relapse. With no clean MADRS cutoff score, the goal of antidepressant therapy should be the lowest possible degree of depressive symptomatology to minimize risk of later relapse. Definitions of remission that are better associated with longer-term outcomes are needed.  相似文献   
68.
The aim of this study is to assess the associations between glycosylated hemoglobin in the prediabetes range and cardiovascular risk markers in a rural South Indian population. Local Ethics Committee approval and informed consent was obtained from all participants. Inclusion criteria were participants, aged ≥20 and ≤85 years, from Nallampatti, a classical farming village from Tamil Nadu State, India. Those with known history of diabetes were excluded from this analysis. All participants were administered a detailed questionnaire, had anthropometric measurements including height, weight, and waist circumference. Bloods were drawn for random blood glucose, glycosylated hemoglobin, nonfasting lipid profile, cystatin C, uric acid, and hemoglobin. All participants had carotid intima thickness done by high-resolution B-mode carotid ultrasound. Progressive hyperglycemia across the glucose tolerance continuum based on glycosylated hemoglobin levels in a rural South Indian population seems to be associated with worsening cardiovascular risk markers. A cut-off value of ≥6% (42 mmol/mol) seems to herald a much more significant increase in such markers. Long-term follow-up of this cohort for incident cardiovascular disease will help to substantiate the associations between glycosylated hemoglobin levels within the prediabetes range and cardiovascular disease in an Indian population. Evidence-based race-specific criteria for diagnosis of prediabetes and diabetes are the need of the hour for risk stratification and appropriate management.  相似文献   
69.
70.
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