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   587篇
  免费   22篇
  国内免费   3篇
林业   100篇
农学   29篇
基础科学   1篇
  72篇
综合类   29篇
农作物   22篇
水产渔业   111篇
畜牧兽医   199篇
园艺   8篇
植物保护   41篇
  2023年   2篇
  2022年   16篇
  2021年   23篇
  2020年   19篇
  2019年   14篇
  2018年   18篇
  2017年   23篇
  2016年   23篇
  2015年   34篇
  2014年   28篇
  2013年   38篇
  2012年   37篇
  2011年   42篇
  2010年   27篇
  2009年   25篇
  2008年   36篇
  2007年   28篇
  2006年   26篇
  2005年   31篇
  2004年   31篇
  2003年   29篇
  2002年   26篇
  2001年   12篇
  2000年   6篇
  1999年   7篇
  1998年   4篇
  1997年   4篇
  1996年   1篇
  1993年   1篇
  1973年   1篇
排序方式: 共有612条查询结果,搜索用时 15 毫秒
611.
The aims of the present study were to identify the differences between two mouse lines (high (H)‐ and low (L)‐oxygen consumption) in terms of mitochondrial respiratory activity when GMP (glutamate, malate, and pyruvate) and succinic acid are used as substrates and to examine the relationship between mitochondrial respiration activity and feed efficiency in both lines. The average daily feed intake, feed conversion ratio (FCR), and residual feed intake (RFI) were significantly higher in the H than the L line. The correlation between FCR and RFI was significant (r = 0.60, p < 0.05). RFI was effective as an indicator of feed efficiency. When succinic acid was used as a substrate, mitochondrial respiration states 2–4, ACR, and proton leak were significantly higher in the H than the L line. When GMP was used as a substrate, respiration states 3 and 4 in the H line were significantly higher than those in the L line, and there were significant positive correlations between FCR and RFI and mitochondrial respiration states 2–4. The results indicated that selection for high or low OC changed the basal metabolic rates estimated from liver mitochondrial respiration activity and feed efficiency.  相似文献   
612.
Motion of mitral valve during cardiac massage was examined using beagle dogs with ventricular fibrillation (n=4). Active compression-decompression cardiac massage (ACD-CM) exhibited greater peak aortic pressure than standard cardiac massage (S-CM), reverse of which was true for peak pulmonary capillary wedge pressure in each animal. Accordingly, peak aortic pressure was greater than peak pulmonary capillary wedge pressure with ACD-CM, whereas its reverse was true with S-CM. Transesophageal echocardiography revealed that mitral valve was incompletely closed with S-CM with showing regurgitation. The valve was more effectively closed during ACD-CM. These results indicate that effective closure of mitral valve during cardiac massage may increase forward blood flow, supporting “cardiac pump theory” rather than “thoracic pump theory” as a principle in dogs.  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