全文获取类型
收费全文 | 108篇 |
免费 | 4篇 |
出版年
2021年 | 1篇 |
2020年 | 2篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 3篇 |
2014年 | 4篇 |
2013年 | 2篇 |
2012年 | 1篇 |
2011年 | 3篇 |
2010年 | 3篇 |
2009年 | 5篇 |
2008年 | 5篇 |
2007年 | 5篇 |
2006年 | 4篇 |
2005年 | 3篇 |
2004年 | 4篇 |
2003年 | 2篇 |
2002年 | 3篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 9篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 6篇 |
1994年 | 2篇 |
1993年 | 4篇 |
1992年 | 5篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1986年 | 2篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有112条查询结果,搜索用时 203 毫秒
101.
102.
An age-dependent decline in hippocampal neurogenesis has been reported in laboratory rodents. Environmental enrichment proved to be a strong trigger of neurogenesis in young and aged laboratory rodents, which are generally kept in facilities with a paucity of environmental stimuli. These data raise the question whether an age-dependent decline in hippocampal cell proliferation and neurogenesis can also be observed in individuals exposed to diversified and varying surroundings. Therefore, we determined rates of canine hippocampal neurogenesis using post-mortem tissue from 37 nonlaboratory dogs that were exposed to a variety of environmental conditions throughout their life. Expression of the neuronal progenitor cell marker doublecortin clearly correlated with age. The analysis of doublecortin-labeled cells in dogs aged > 133 months indicated a 96% drop in the aged canine brain as compared to young adults. Expression of the proliferation marker Ki-67 in the subgranular zone decreased until dogs were aged 85-132 months. In the aging canine brain amyloid-beta peptide deposits have been described that might resemble an early pathophysiological change in the course of human Alzheimer's disease. Comparison of Ki-67 and doublecortin expression in canine brain tissue with or without diffuse plaques revealed no differences. The data indicate that occurrence of diffuse plaques in the aging brain is not sufficient to trigger enhanced proliferation or enhanced neurogenesis such as described in human Alzheimer's disease. In addition, this study gives first proof that an age-dependent decline also dominates hippocampal neurogenesis rates in individuals living in diversified environments. 相似文献
103.
C Tardif H Maamar M Balfin JP Belaich 《Journal of industrial microbiology & biotechnology》2001,27(5):271-274
Electropermeabilization of Clostridium cellulolyticum was optimized using ATP leakage assays. Electrotransformation was then performed under optimized conditions (6 to 7.5 kV
cm−1 field strength applied during 5 ms to a mixture containing methylated plasmids and late exponential phase cell suspensions
(10 molecules:1 cell) in a sucrose-containing buffer). Transformants were only obtained when 7 or 7.5 kV cm−1 pulses were applied. Transformation efficiencies evaluated from the growth curves of transformed cells were between 105 and 107 transformants per microgram of plasmid DNA for five different replicon-based plasmids. Restriction nuclease digestion patterns
of pJIR418 purified from transformed Clostridia and Escherichia coli were indistinguishable, indicating that heterologous DNA was structurally stable in the Clostridium strain. Copy numbers of 130, 70 and 10 were estimated from purification yield for pCTC1, pKNT19 and pJIR418, respectively.
Journal of Industrial Microbiology & Biotechnology (2001) 27, 271–274.
Received 12 September 2000/ Accepted in revised form 25 November 2000 相似文献
104.
Gill Furze Alun Roebuck Peter Bull Robert JP Lewin David R Thompson 《BMC cardiovascular disorders》2002,2(1):4
Background
What people believe about their illness may affect how they cope with it. It has been suggested that such beliefs stem from those commonly held within society . This study compared the beliefs held by people with angina, regarding causation and coping in angina, with the beliefs of their friends who do not suffer from angina. 相似文献105.
Publication of the complete diploid genome sequence of the yeast Candida albicans will accelerate research into the pathogenesis of Candida infections. Comparative genomic analysis highlights genes that may contribute to C. albicans survival and its fitness as a human commensal and pathogen. 相似文献
106.
The principal aim of this study was to evaluate dissociative anaesthesia for castration of colts during field conditions. Three dissociative anaesthetic protocols were evaluated during castration of colts in an animal hospital. The protocol considered to be the most suitable was thereafter evaluated during castration of colts under field conditions. Respiratory and haemodynamic parameters and the response to surgery were determined during anaesthesia. All horses breathed air spontaneously during anaesthesia. Under hospital conditions 26 colts were randomised to receive one of three anaesthetic protocols: Romifidine and tiletamine-zolazepam (RZ); acepromazine, romifidine and tiletamine-zolazepam (ARZ); or acepromazine, romifidine, butorphanol and tiletamine-zolazepam (ARBZ). The surgeon was blinded to the anaesthetic protocol used and decided whether supplemental anaesthesia was needed to complete surgery. Under field conditions 31 colts were castrated during anaesthesia with the ARBZ protocol. All inductions, anaesthesia and recoveries were calm and without excitation under both hospital and field conditions. Surgery was performed within 5–20 minutes after the horses had assumed lateral recumbency during both hospital and field castrations. Under hospital conditions some horses needed supplemental anaesthesia with all three anaesthetic protocols to complete surgery. Interestingly, none of the horses castrated with protocol ARBZ under field conditions needed additional anaesthesia. Cardiorespiratory changes were within acceptable limits in these clinically healthy colts. 相似文献
107.
Alistair JP Brown 《Genome biology》2010,11(5):302
A report of the symposium on Signaling and Systems Biology held during the Society for General Microbiology Spring Meeting,
29-30 March 2010, Edinburgh, UK. 相似文献
108.
109.
110.