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   39篇
  免费   0篇
化学   13篇
数学   3篇
物理学   23篇
  2021年   1篇
  2013年   1篇
  2011年   1篇
  2008年   1篇
  2004年   2篇
  2002年   1篇
  2001年   1篇
  2000年   5篇
  1999年   3篇
  1998年   2篇
  1996年   3篇
  1995年   3篇
  1994年   1篇
  1993年   4篇
  1991年   1篇
  1990年   1篇
  1987年   2篇
  1986年   1篇
  1980年   1篇
  1978年   1篇
  1975年   1篇
  1974年   1篇
  1971年   1篇
排序方式: 共有39条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
A novel supramolecular host for the uranyl carbonate complex has been designed and synthesized. The modified cyclodextrin host binds uranyl carbonate in water with a stability of 253 M(-1).  相似文献   
7.
8.
9.
A general method has been developed for the rapid, metal-catalysed transfer reduction of nitro compounds to N-substituted hydroxylamines.  相似文献   
10.
Gastric and small intestinal myoelectric and motor activity is divided into two main patterns, fed and fasted. During fasting, the predominant pattern of activity is the migrating myoelectric complex (MMC), a cyclically occurring pattern of electric and mechanical activity that is initiated in the stomach and duodenum almost simultaneously and, from there, propagates the length of the small intestine. Cyclic motor activity also occurs in the lower esophageal sphincter, the gallbladder, and the sphincter of Oddi with a duration that is related to the MMC in the small intestine. Of the possible mechanisms for initiation of the MMC in the small intestine (extrinsic neural control, intrinsic neural control, and hormonal control), intrinsic neural control via a series of coupled is the most likely. The keep this sentence in! hormone motilin also plays a role in the initiation of MMCs. After a meal, in man the MMC is disrupted and replaced by irregular contractions. The physiologic role of the MMC is to clear the stomach and small intestine of residual food, secretions, and desquamated cells and propel them to the colon. Disruption of the MMC cycle is associated with bacterial overgrowth in some patients, an observation that supports the proposed cleansing function of the MMC cycle.  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