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   40716篇
  免费   2760篇
  国内免费   149篇
耳鼻咽喉   445篇
儿科学   1310篇
妇产科学   822篇
基础医学   5525篇
口腔科学   1120篇
临床医学   4078篇
内科学   8170篇
皮肤病学   592篇
神经病学   4168篇
特种医学   1537篇
外国民族医学   7篇
外科学   5861篇
综合类   466篇
一般理论   54篇
预防医学   2925篇
眼科学   1265篇
药学   2882篇
  1篇
中国医学   56篇
肿瘤学   2341篇
  2022年   229篇
  2021年   495篇
  2020年   338篇
  2019年   533篇
  2018年   629篇
  2017年   522篇
  2016年   577篇
  2015年   654篇
  2014年   908篇
  2013年   1514篇
  2012年   2279篇
  2011年   2442篇
  2010年   1341篇
  2009年   1293篇
  2008年   2339篇
  2007年   2662篇
  2006年   2596篇
  2005年   2604篇
  2004年   2514篇
  2003年   2434篇
  2002年   2302篇
  2001年   614篇
  2000年   546篇
  1999年   574篇
  1998年   550篇
  1997年   495篇
  1996年   378篇
  1995年   401篇
  1994年   370篇
  1993年   378篇
  1992年   435篇
  1991年   403篇
  1990年   372篇
  1989年   392篇
  1988年   342篇
  1987年   324篇
  1986年   365篇
  1985年   363篇
  1984年   419篇
  1983年   413篇
  1982年   418篇
  1981年   385篇
  1980年   399篇
  1979年   307篇
  1978年   282篇
  1977年   271篇
  1976年   199篇
  1975年   207篇
  1974年   200篇
  1973年   162篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
141.
Abstract During treatment of femoral shaft fractures, not only the actual fracture reduction but also the retention of the achieved reduction is essential. Substantial forces may apply to the bone fragments, due to multidirectional muscular contraction. Furthermore, forces from manipulation of one bone fragment may be transferred over the soft tissues onto the other fragments, thus hindering accurate fracture reduction. Once a sufficient reduction has been achieved, this position must be retained whilst definitive internal fixation is performed. Conventional methods comprise mounting patients on a traction table and applying manual distraction or employing special distraction devices, such as the AO distractor device. These approaches, however, only insufficiently stabilize both main fragments. For example, on the traction table the proximal femoral fragment can pivot around the hip joint thus complicating precise reduction. A novel pneumatic stabilization device to assist surgeons during operative procedures is described. This passive holding device “Passhold” connects to one main fragment through a minimally invasive bone interface and statically locks the fragment’s position. Thereafter, only the other main fragment is manipulated to achieve reduction. Mutual interference of the reciprocal fragment positions, due to soft-tissue force transfer during manipulation, is avoided. The authors examined the stability of the novel retention device on a test rig and proved its functionality under sterile settings using cadaver tests. It is concluded that this device largely facilitates the operative procedure in femoral shaft fractures, is sufficiently stable and ergonomically suitable for intraoperative deployment.  相似文献   
142.
The effectiveness of interdisciplinary treatments for chronic pain is well established. In general, these treatments decrease psychosocial distress and increase physical abilities. Further, return to work rates following interdisciplinary treatment tend to be quite high. Previous studies have highlighted a number of factors that individually influence return to work rates; however, there is a need for more comprehensive and unified models that allow an evaluation of the inter-relations among these factors. The present investigation examined how demographic and treatment outcome variables interacted to influence post-treatment return to work rates in a sample of individuals with chronic pain following interdisciplinary treatment. Results indicated that patient age, lifting ability, pain duration, depression level, and reported disability were individually related to return to work; however, when these variables were evaluated relative to one another, level of depression and patient age had the best ability to predict post-treatment work status. These results add to the literature by specifically highlighting post-treatment factors that best discriminate patients who had returned to work from those that had not. Furthermore, they provide evidence that general emotional distress is perhaps the most important predictor of work status following treatment.  相似文献   
143.
144.
145.
146.
147.
BACKGROUND AND PURPOSE: Intimal-medial thickening (IMT) of the carotid wall is an accepted peripheral marker of atherosclerosis. It is associated with increased risk for myocardial infarction and stroke, and lower attention-executive-psychomotor functioning. The purpose of this study was to examine the relationship between IMT and brain activity during a verbal working memory (VWM) task in patients with cardiovascular disease (CVD). METHODS: Thirteen CVD patients underwent functional magnetic resonance imaging (fMRI) during a 2-Back VWM task, and B-mode ultrasound of the carotid arteries. IMT was calculated using an automated algorithm based on a validated edge-detection technique. The relationship between IMT and 2-Back-related brain activity was modeled using partial correlations controlling for age and small vessel disease as measured by white matter signal hyperintensities on MRI (WMH). RESULTS: Higher IMT was associated with lower 2-Back-related signal intensity and in the right middle frontal gyrus, independent of age and WMH. CONCLUSIONS: IMT may be one mechanism contributing to brain dysfunction in CVD. The blood oxygenation level-dependent (BOLD) contrast appears to be highly sensitive to peripheral vascular health as measured by IMT. Future studies should examine the sensitivity and specificity of the BOLD response for predicting cognitive decline in CVD.  相似文献   
148.
Zusammenfassung Auf Grund unserer vergleichenden Versuche empfehlen wir, neben der WaR. stets mehrere Trübungs- und Flockungsreaktionen auszuführen. Als recht brauchbar haben sich uns die Kahn-, Citochol- und Meinicke-Trübungs-Reaktion erwiesen, da sie schnell und leicht anzustellen und abzulesen und hinsichtlich Empfindlichkeit und Spezifität der WaR. gleichgestellt, in manchen Fällen sogar überlegen sind.  相似文献   
149.
150.
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