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   789篇
  免费   75篇
  2023年   21篇
  2022年   17篇
  2021年   41篇
  2020年   22篇
  2019年   27篇
  2018年   32篇
  2017年   28篇
  2016年   33篇
  2015年   46篇
  2014年   41篇
  2013年   65篇
  2012年   71篇
  2011年   54篇
  2010年   38篇
  2009年   35篇
  2008年   41篇
  2007年   32篇
  2006年   28篇
  2005年   21篇
  2004年   24篇
  2003年   24篇
  2002年   28篇
  2001年   10篇
  2000年   11篇
  1999年   16篇
  1997年   7篇
  1996年   4篇
  1995年   2篇
  1994年   6篇
  1993年   1篇
  1992年   4篇
  1991年   4篇
  1990年   4篇
  1989年   2篇
  1988年   4篇
  1987年   3篇
  1986年   1篇
  1985年   2篇
  1984年   3篇
  1983年   3篇
  1982年   1篇
  1981年   1篇
  1980年   1篇
  1979年   2篇
  1978年   1篇
  1976年   1篇
  1973年   1篇
排序方式: 共有864条查询结果,搜索用时 93 毫秒
851.
852.
853.
Doklady Biochemistry and Biophysics - To search for compounds with antiprotozoal activity, effects of snake venoms on the ciliates Tetrahymena pyriformis was studied. T. pyriformis from subkingdom...  相似文献   
854.
Autoagglutinable strains of Vibrio cholerae O1 (seven nonfimbriate strains and one fimbriate strain) were transformed to obtain resistance to ampicillin. Two distinct mechanisms were found in these strains. One was operating in nonfimbriate strains by reducing OmpU protein production and the other was operating in a fimbriate strain (Bgd17) by newly overproducing cpxP protein. The twitching motility in the fimbriate Bgd17 strain disappeared depending on the production of cpxP protein, suggesting that fimbriation of V. cholerae O1 is controlled by a two-component signal transduction system.  相似文献   
855.
Renal cytosolic extracts from rats of different ages and mononephrectomized rats were incubated with gamma-[32P]ATP and analysed by high resolution two-dimensional electrophoresis and autoradiography. Extracts from new-born and young rats showed a great number of phosphorylated proteins migrating between the origin and Mr 52,000. Among these proteins, the group co-migrating with phosphorylase b (Mr 97,000) was particularly evident in new-born and days-old rats. In extracts from mature rats, other proteins of lower molecular weight, particularly those migrating between Mr 60,000 and 44,000, became intensely phosphorylated. The number and intensity of phosphorylated proteins from extracts of normal and nephrectomized rats, however, did not vary. Activity of cAMP-dependent protein kinase and [3H]cAMP binding was also modified during neonatal development but not in compensatory renal growth. Since cAMP-PK and protein phosphorylation are known to be regulated in response to hormonal stimulations, these results may provide good indications for the understanding of hormonal involvement in kidney growth.  相似文献   
856.
Applied Microbiology and Biotechnology - Shiga toxin-producing Escherichia coli (STEC) O157:H7 and extended-spectrum beta-lactamase (ESBL) producing E. coli (ESBLEC) are important bacteria of...  相似文献   
857.
Therapeutic protein productivity and glycosylation pattern highly rely on cell metabolism. Cell culture medium composition and feeding strategy are critical to regulate cell metabolism. In this study, the relationship between toxic metabolic inhibitors and their nutrient precursors was explored to identify the critical medium components toward cell growth and generation of metabolic by-products. Generic CHO metabolic model was tailored and integrated with CHO fed-batch metabolomic data to obtain a cell line- and process-specific model. Flux balance analysis study was conducted on toxic metabolites cytidine monophosphate, guanosine monophosphate and n-acetylputrescine—all of which were previously reported to generate from endogenous cell metabolism—by mapping them to a compartmentalized carbon utilization network. Using this approach, the study projected high level of inhibitory metabolites accumulation when comparing three industrially relevant fed-batch feeding conditions one against another, from which the results were validated via a dose-dependent amino acids spiking study. In the end, a medium optimization design was employed to lower the amount of supplemented nutrients, of which improvements in critical process performance were realized at 40% increase in peak viable cell density (VCD), 15% increase in integral VCD, and 37% increase in growth rate. Tight control of toxic by-products was also achieved, as the study measured decreased inhibitory metabolites accumulation across all conditions. Overall, the study successfully presented a digital twin approach to investigate the intertwined relationship between supplemented medium constituents and downstream toxic metabolites generated through host cell metabolism, further elucidating different control strategies capable of improving cellular phenotypes and regulating toxic inhibitors.  相似文献   
858.
859.
860.
Journal of Applied Phycology - The red alga Kappaphycus striatus “sacol” brown strain is an economically important species and extensively cultivated at Vanphong Bay, Vietnam. To...  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