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   18681篇
  免费   1798篇
  国内免费   43篇
耳鼻咽喉   163篇
儿科学   502篇
妇产科学   335篇
基础医学   2745篇
口腔科学   407篇
临床医学   2216篇
内科学   3959篇
皮肤病学   436篇
神经病学   1513篇
特种医学   502篇
外科学   3187篇
综合类   406篇
一般理论   13篇
预防医学   1582篇
眼科学   267篇
药学   1295篇
中国医学   14篇
肿瘤学   980篇
  2021年   248篇
  2020年   189篇
  2019年   287篇
  2018年   275篇
  2017年   266篇
  2016年   286篇
  2015年   304篇
  2014年   419篇
  2013年   595篇
  2012年   956篇
  2011年   915篇
  2010年   490篇
  2009年   497篇
  2008年   783篇
  2007年   836篇
  2006年   833篇
  2005年   829篇
  2004年   768篇
  2003年   758篇
  2002年   694篇
  2001年   570篇
  2000年   666篇
  1999年   521篇
  1998年   212篇
  1997年   189篇
  1996年   183篇
  1995年   165篇
  1994年   158篇
  1993年   162篇
  1992年   482篇
  1991年   461篇
  1990年   401篇
  1989年   398篇
  1988年   393篇
  1987年   364篇
  1986年   358篇
  1985年   327篇
  1984年   319篇
  1983年   224篇
  1982年   145篇
  1981年   141篇
  1980年   134篇
  1979年   264篇
  1978年   163篇
  1977年   131篇
  1976年   138篇
  1974年   168篇
  1973年   166篇
  1972年   157篇
  1971年   123篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
1.
2.
3.
4.
5.
6.
7.
We update a patient series that reported a high incidence of infection with Gram-positive cocci in women treated with the combination of pertuzumab and trastuzumab and further characterize this clinical problem. Treating physicians and advanced practice partners identified women who developed infections while on treatment with pertuzumab and trastuzumab alone or in combination with chemotherapy and enrolled them onto this registry trial. Between March, 2014 and May, 2017, 48 patients with HER2-positive breast cancers were reported to have 59 individual infections. The median age was 48 years. Twenty-four patients received neoadjuvant therapy, 17 were treated for metastatic disease, and 7 were treated in the adjuvant setting. Pertuzumab and trastuzumab were combined with carboplatin and docetaxel in 24 (49%) patients, docetaxel in 10 (21%), nab-paclitaxel in 12 (24%), and without other agents in 2 (4%). Granulocyte growth factors were administered in 24 (49%) patients and no patients were documented to be neutropenic. Folliculitis developed in 25 (52%) patients and was counted as a single infection. Abscesses developed at a number of sites in 24 (49%) patients, including a septic knee requiring total knee replacement. Paronychia occurred in 7 (15%) patients, and 5 (10%) developed cellulitis. When cultures were obtained, Gram-positive cocci were consistently identified. Hypogammaglobulinemia was documented in 14 (36%) of the 33 patients tested. Our data continue to support an increased risk of infections with Gram-positive cocci as a potentially serious adverse event in women treated with pertuzumab and trastuzumab.  相似文献   
8.
9.
Recently, we developed a high-frame-rate echocardiographic imaging system capable of acquiring images at rates up to 2500 per second. High imaging rates were used to quantify longitudinal strain parameters in patients with echocardiographically normal function. These data can serve as a baseline for comparing strain parameters in disease states. The derived timing data also reveal the propagation of mechanical events in the left ventricle throughout the cardiac cycle. High-frame-rate echocardiographic images were acquired from 17 patients in the apical four-chamber view using Duke University's phased array ultrasound system, T5. B-Mode images were acquired at 500–1000 images per second by employing 16:1 or 32:1 parallel processing in receive, a scan depth ≤14 cm and an 80° field of view with a 3.5-MegaHertZ (MHz), 96-element linear array. The images were analyzed using a speckle tracking algorithm tailored for high-frame-rate echocardiographic images developed at Aalborg and Duke University. Four specific mechanical events were defined using strain curves from six regions along the myocardial contour of the left ventricle. The strain curves measure the local deformation events of the myocardium and are independent of the overall cardiac motion. We observed statistically significant differences in the temporal sequence among different myocardial segments for the first mechanical event described, myocardial tissue shortening onset (p < 0.01). We found that the spatial origin of tissue shortening was located near the middle of the interventricular septum in patients with echocardiographically normal function. The quantitative parameters defined here, based on high-speed strain measurements in patients with echocardiographically normal function, can serve as a means of assessing degree of contractile abnormality in the myocardium and enable the identification of contraction propagation. The relative timing pattern among specific events with respect to the Q wave may become an important new metric in assessing cardiac function and may, in turn, improve diagnosis and prognosis.  相似文献   
10.
ObjectiveThe purpose of this study was to quantify the impact of a single lumbar spinal manipulation (SM) intervention on the leg movement performance of degenerative lumbar spinal stenosis (LSS) patients in a small-scale registered randomized clinical trial.MethodsParticipants with LSS (n = 14) were tested at baseline for pain, lumbar range of motion, and behavioral or kinematic motor performance (using an established Fitts’ Law foot-pointing task), then underwent covariate adaptive randomization to receive SM or no intervention. Postintervention all dependent measures were repeated. Experimenters were blinded to patient group allocation. University ethics board approval was attained.ResultsFor the primary outcome movement time, there was no significant difference between groups. As predicted by Fitts’ Law, all participants had longer movement times as task difficulty increased. Secondary kinematic outcomes yielded no significant between-group differences. Consistent with Fitts’ Law, kinematic measures changed significantly with task difficulty. Pairwise comparisons revealed the kinematic variables were more adversely affected by greater movement amplitudes than target size changes. No exploratory differences in pain or lumbar range of motion were observed.ConclusionChanges in motor performance were not observed in this chronic pain population after a single SM intervention compared with a control group. Given the sample size, the study may have been underpowered to detect meaningful differences. Fitts’ Law was observed for the lower extremity–pointing task for an LSS population and may provide an objective measure of motor performance.  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