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   476篇
  免费   8篇
化学工业   41篇
能源动力   1篇
轻工业   9篇
无线电   10篇
一般工业技术   12篇
冶金工业   401篇
自动化技术   10篇
  2019年   4篇
  2017年   3篇
  2016年   4篇
  2015年   4篇
  2013年   5篇
  2011年   3篇
  2010年   3篇
  2009年   4篇
  2007年   5篇
  2006年   6篇
  2005年   5篇
  2004年   9篇
  2002年   3篇
  2001年   4篇
  2000年   3篇
  1999年   11篇
  1998年   122篇
  1997年   65篇
  1996年   47篇
  1995年   30篇
  1994年   22篇
  1993年   28篇
  1992年   1篇
  1991年   2篇
  1990年   1篇
  1989年   3篇
  1988年   3篇
  1987年   3篇
  1986年   4篇
  1985年   5篇
  1984年   1篇
  1982年   5篇
  1981年   5篇
  1980年   6篇
  1978年   3篇
  1977年   20篇
  1976年   31篇
  1975年   1篇
排序方式: 共有484条查询结果,搜索用时 15 毫秒
31.
The dendritic localization of mRNAs has been proposed to underlie the structural and functional polarity of neurons, as well as certain aspects of synaptic plasticity. Even though there is no conclusive evidence that such a localization is a physiological requirement, studies of mRNA localization in relation to function in other cell types and recent experiments on synaptic plasticity suggest that this proposal may be correct.  相似文献   
32.
Diets, energy expenditures, physical and mental performance, anthropometric indices, ascorbic acid excretion, and morbidity rates were studied in 7-9-year-old schoolchildren of Monchegorsk, Murmansk Region. The alimentary features found served as the basis for developing sanitary recommendations to optimize diets and to promote children's health.  相似文献   
33.
34.
35.
36.
A model of postsynaptic processes leading to a prolonged posttetanic modification (potentiation and depression) in the efficacy of the excitatory and inhibitory inputs to the neuron CA3 of the hippocampus was developed. The model enables one to estimate changes in postsynaptic potentials depending on the extent of receptor phosphorylation, which is determined by Ca(2+)-dependent changes in secondary messengers.  相似文献   
37.
OBJECTIVE AND DESIGN: The limitation of activity and its modification by therapy in an experimental arthritis was studied. SUBJECTS: Female hamsters in groups of six per treatment were used. TREATMENT: An acute arthritis was induced by intraarticular injection of 0.1 microgram lipopolysaccharide (LPS) in hamsters with free access to running wheels. Tenidap at 100 mg%, and piroxicam and indomethacin at 30 mg% were administered in the hamster's normal diet. METHODS: Activity was monitored and analysed by computer. Plasma blood levels of drugs were determined by high pressure liquid chromatographic (HPLC) analysis. RESULTS: Hamsters normally run 10-15 km/day. That distance was reduced to less than 2 km/day after arthritis induction. Speed of movement, essentially the equivalent of walking time, was reduced 40% by the arthritis. However, the time spent in movement (activity time) was more severely affected by arthritic disease. Therapy gave a modest 1.3-fold increase in speed of movement, but a highly significant 2-fold increase in activity time. CONCLUSIONS: The effects of arthritis on activity in this animal model suggest that time spent in movement (activity time) should be considered as an outcome measure in clinical studies. These observations may also help explain why the modest disease improvements obtained with cyclooxygenase inhibition are valued. From a patient perspective, a doubling of activity time is a highly significant improvement in quality-of-life.  相似文献   
38.
39.
40.
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