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   571篇
  免费   39篇
  国内免费   105篇
儿科学   28篇
妇产科学   4篇
基础医学   77篇
口腔科学   32篇
临床医学   105篇
内科学   157篇
皮肤病学   6篇
神经病学   31篇
特种医学   69篇
外科学   23篇
综合类   38篇
预防医学   32篇
眼科学   5篇
药学   73篇
中国医学   1篇
肿瘤学   34篇
  2021年   6篇
  2020年   5篇
  2019年   6篇
  2018年   11篇
  2017年   11篇
  2016年   11篇
  2015年   14篇
  2014年   13篇
  2013年   24篇
  2012年   26篇
  2011年   23篇
  2010年   29篇
  2009年   25篇
  2008年   21篇
  2007年   72篇
  2006年   25篇
  2005年   27篇
  2004年   17篇
  2003年   9篇
  2002年   16篇
  2001年   9篇
  2000年   16篇
  1999年   11篇
  1998年   46篇
  1997年   37篇
  1996年   38篇
  1995年   17篇
  1994年   22篇
  1993年   14篇
  1992年   10篇
  1991年   3篇
  1990年   11篇
  1989年   13篇
  1988年   14篇
  1987年   12篇
  1986年   12篇
  1985年   5篇
  1984年   3篇
  1982年   3篇
  1981年   4篇
  1980年   3篇
  1979年   1篇
  1978年   1篇
  1977年   4篇
  1976年   6篇
  1975年   3篇
  1974年   1篇
  1971年   1篇
  1965年   1篇
  1960年   1篇
排序方式: 共有715条查询结果,搜索用时 15 毫秒
91.
92.
IntroductionAcute respiratory distress syndrome (ARDS) is a common clinical syndrome with high mortality and long-term morbidity. To date there is no effective pharmacological therapy. Aspirin therapy has recently been shown to reduce the risk of developing ARDS, but the effect of aspirin on established ARDS is unknown.MethodsIn a single large regional medical and surgical ICU between December 2010 and July 2012, all patients with ARDS were prospectively identified and demographic, clinical, and laboratory variables were recorded retrospectively. Aspirin usage, both pre-hospital and during intensive care unit (ICU) stay, was included. The primary outcome was ICU mortality. We used univariate and multivariate logistic regression analyses to assess the impact of these variables on ICU mortality.ResultsIn total, 202 patients with ARDS were included; 56 (28%) of these received aspirin either pre-hospital, in the ICU, or both. Using multivariate logistic regression analysis, aspirin therapy, given either before or during hospital stay, was associated with a reduction in ICU mortality (odds ratio (OR) 0.38 (0.15 to 0.96) P = 0.04). Additional factors that predicted ICU mortality for patients with ARDS were vasopressor use (OR 2.09 (1.05 to 4.18) P = 0.04) and APACHE II score (OR 1.07 (1.02 to 1.13) P = 0.01). There was no effect upon ICU length of stay or hospital mortality.ConclusionAspirin therapy was associated with a reduced risk of ICU mortality. These data are the first to demonstrate a potential protective role for aspirin in patients with ARDS. Clinical trials to evaluate the role of aspirin as a pharmacological intervention for ARDS are needed.  相似文献   
93.
94.
95.
96.
Ghetie  MA; Picker  LJ; Richardson  JA; Tucker  K; Uhr  JW; Vitetta  ES 《Blood》1994,83(5):1329-1336
In this report, we extend our previous findings that IgG or F(ab')2 fragments of HD37 anti-CD19 antibody (Ab) in combination with the immunotoxin (IT), RFB4-anti-CD22-deglycosylated ricin A chain (dgA) (but neither reagent alone), prolonged the survival of SCID mice with disseminated human Daudi lymphoma (SCID/Daudi mice) to 1 year at which time they still remained tumor-free. We explored the mechanisms by which the HD37 Ab exerts antitumor activity in vivo by studying its activity in vitro. We found that it has antiproliferative activity (IC50 = 5.2 - 9.8 x 10(-7) mol/L) on three CD19+ Burkitt's lymphoma cell lines (Daudi, Raji, and Namalwa) but not on a weakly CD19-positive (CD19lo) pre-B cell tumor (Nalm-6). The inhibitory effect was manifested by cell cycle arrest, but not apoptosis. Results using three additional anti-CD19 Abs, suggest that the affinity of the antibody and possibly the epitope which it recognizes may effect its capacity to transmit a signal that induces cell cycle arrest. Hence, therapeutically useful Abs may exert anti-tumor activity by a variety of mechanisms, each of which should be evaluated before undertaking clinical trials in humans.  相似文献   
97.
Studies of circulating hemopoietic progenitor cells in human fetal blood   总被引:3,自引:0,他引:3  
Linch  DC; Knott  LJ; Rodeck  CH; Huehns  ER 《Blood》1982,59(5):976-979
High levels of committed erythroid and granulocytic/monocytic progenitor cells have been demonstrated in fresh blood obtained at fetoscopy. The fetal progenitor cells were more sensitive to appropriate stimuli (erythropoietin and colony-stimulating factor) than adult progenitor cells grown under the same conditions, and this was shown to be due to intrinsic differences in the progenitor cells at the different developmental stages.  相似文献   
98.
Integration of local inputs in visual cortex   总被引:1,自引:0,他引:1  
In mammalian visual cortex, local connections are ubiquitous, extensively linking adjacent neurons of all types. In this study, optical maps of intrinsic signals and responses from single neurons were obtained from the same region of cat visual cortex while the effectiveness of the local cortical circuitry was altered by focally disinhibiting neurons within a column of known orientation preference. Maps of intrinsic signals indicated that local connections provide strong and functional subthreshold inputs to neighboring columns of other orientation preferences, altering the observed orientation preference to that of the disinhibited column. However, measuring the suprathreshold response using single-cell recordings revealed only mild changes of preferred orientation over the affected region. Because strongly tuned subthreshold inputs from cortex only marginally affect the tuning of a cortical cell's output, it is concluded that local cortical inputs are integrated weakly compared to geniculate inputs. Such circuitry potentially allows for the normalization of responses across a wide range of input activity through local averaging.   相似文献   
99.
100.
MR imaging of ductal carcinoma in situ   总被引:15,自引:0,他引:15  
  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