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   754篇
  免费   57篇
  2016年   16篇
  2015年   10篇
  2014年   6篇
  2013年   48篇
  2012年   13篇
  2011年   25篇
  2010年   23篇
  2009年   17篇
  2008年   29篇
  2007年   30篇
  2006年   29篇
  2005年   29篇
  2004年   32篇
  2003年   41篇
  2002年   30篇
  2001年   11篇
  2000年   9篇
  1999年   12篇
  1998年   17篇
  1997年   10篇
  1996年   9篇
  1995年   9篇
  1994年   11篇
  1993年   14篇
  1992年   16篇
  1991年   11篇
  1990年   20篇
  1989年   7篇
  1988年   9篇
  1987年   15篇
  1986年   10篇
  1985年   13篇
  1984年   14篇
  1983年   13篇
  1982年   11篇
  1981年   13篇
  1980年   16篇
  1979年   14篇
  1978年   9篇
  1976年   12篇
  1975年   11篇
  1974年   16篇
  1973年   9篇
  1972年   14篇
  1971年   9篇
  1970年   5篇
  1969年   8篇
  1968年   7篇
  1967年   5篇
  1965年   5篇
排序方式: 共有811条查询结果,搜索用时 46 毫秒
1.
Cerebral edema is a common complication following moderate and severe traumatic brain injury (TBI), and a significant risk factor for development of neuronal death and deterioration of neurological outcome. To this date, medical approaches that effectively alleviate cerebral edema and neuronal death after TBI are not available. Glucagon-like peptide-1 (GLP-1) has anti-inflammatory properties on cerebral endothelium and exerts neuroprotective effects. Here, we investigated the effects of GLP-1 on secondary injury after moderate and severe TBI. Male Sprague Dawley rats were subjected either to TBI by Controlled Cortical Impact (CCI) or sham surgery. After surgery, vehicle or a GLP-1 analogue, Liraglutide, were administered subcutaneously twice daily for two days. Treatment with Liraglutide (200 μg/kg) significantly reduced cerebral edema in pericontusional regions and improved sensorimotor function 48 hours after CCI. The integrity of the blood-brain barrier was markedly preserved in Liraglutide treated animals, as determined by cerebral extravasation of Evans blue conjugated albumin. Furthermore, Liraglutide reduced cortical tissue loss, but did not affect tissue loss and delayed neuronal death in the thalamus on day 7 post injury. Together, our data suggest that the GLP-1 pathway might be a promising target in the therapy of cerebral edema and cortical neuronal injury after moderate and severe TBI.  相似文献   
2.
Sulphatides (ceramide galactose-3-sulphate) were isolated from human erythrocyte membranes. The amount obtained was 3.3 mg from 6.7 kg of wet cells, or 1.5 X 10(-9) mol per g dry cells. The polar part was shown to be galactose-3-sulphate by chromatographic analysis, infrared spectrometry, and mass spectrometry after solvolytic desulphation. The ceramide part consisted of three major molecular species, sphingosine-palmitic acid, sphingosine-2-hydroxypalmitic acid, and phytosphingosine-2-hydroxypalmitic acid, as shown by thin-layer chromatography, mass spectrometry of galactosylceramides after desulphation, and gas chromatography of components after hydrolysis. The composition differed from other human erythrocyte sphingolipids. Although the amount of sulphatides is very low for erythrocyte, the ratio of sulphatide concentration and Na+-K+-ATPase activity [EC 3.6.1.3] is similar to the situation found for several animal tissues with an increased level of Na+ transport. This finding is discussed in relation to a recent model of sulphatide function in a transport unit for Na+ and K+ (cofactor site model).  相似文献   
3.
Effects of eccentric exercise on the immune system in men   总被引:10,自引:0,他引:10  
The effects of eccentric exercise on changes innumbers of circulating leukocytes, cell activation, cell adhesion, andcellular memory function were investigated in 12 men, aged 22-35yr. The immunologic effects of postexercise epidermal treatment withmonochromatic, infrared light were also evaluated. Blood was drawnbefore and 6, 24, and 48 h after exercise for phenotyping and analysisof creatine kinase activity. There was an increase in leukocyte, monocyte, and neutrophil number, no change in the number of basophils, eosinophils, B cells, and T cells, and a decrease in natural killer cell number postexercise. Some markers of lymphocyte and monocyte activation remained unchanged or decreased, whereas the expression ofadhesion molecules 62L and 11b increased on monocytes. It is concludedthat eccentric exercise induced decreased activation, and increasedcell adhesion capacity, of monocytes. Altered trafficking of cellsbetween lymphoid tissue and blood, selective apoptosis, orattachment/detachment from the endothelial wall can explain theobserved phenotypic changes. Treatment with monochromatic, infraredlight did not significantly affect any of the investigated variables.Correlations between immunologic and physiological parameters indicatea role of the immune system in adaptation to physical exercise.  相似文献   
4.
5.
6.
7.
14,15-Leukotriene A4 is a pivotal biosynthetic intermediate in 15-lipoxygenase initiated leukotriene biosynthesis. This compound hydrolyzes instantaneously in phosphate buffer at pH 7.4. However, addition of human or bovine albumin to otherwise identical buffer solutions increases its stability. Intact 14,15-leukotriene A4 then decomposes by first-order kinetics with rate constants inversely proportional to the albumin concentration. Stabilization of 14,15-leukotriene A4 under certain conditions may influence its proportionate transformation by enzymatic vs non-enzymatic processes.  相似文献   
8.
9.
The genus Theophrasta is endemic to the island of Hispaniola. Two species are recognized, viz. T. jussieui and T. americana. T. jussieui is restricted to the central part of northern Haiti, whereas the latter is distributed over most of Hispaniola. Only floral characters have been practically useful to distinguish the species. T. jussieui differs from T. americana primarily by its larger flowers and inflorescences. The two species are considered closely related. An investigation of leaf surface structures and foliar anatomy, particular the sclerenchyma, is presented. Floral biology, including adaptions to sapromyophilous pollination, is described and discussed, and notes on habit, ecology, and pollen morphology are given.  相似文献   
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