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   1328篇
  免费   87篇
  1415篇
  2024年   2篇
  2023年   7篇
  2022年   43篇
  2021年   65篇
  2020年   35篇
  2019年   34篇
  2018年   27篇
  2017年   44篇
  2016年   54篇
  2015年   61篇
  2014年   67篇
  2013年   105篇
  2012年   129篇
  2011年   104篇
  2010年   56篇
  2009年   56篇
  2008年   74篇
  2007年   65篇
  2006年   72篇
  2005年   68篇
  2004年   65篇
  2003年   41篇
  2002年   35篇
  2001年   17篇
  2000年   14篇
  1999年   10篇
  1998年   3篇
  1997年   5篇
  1996年   5篇
  1995年   4篇
  1994年   6篇
  1992年   3篇
  1991年   4篇
  1990年   4篇
  1989年   4篇
  1987年   5篇
  1986年   2篇
  1985年   2篇
  1984年   2篇
  1983年   2篇
  1982年   1篇
  1981年   1篇
  1979年   3篇
  1972年   1篇
  1968年   1篇
  1967年   1篇
  1966年   1篇
  1965年   1篇
  1954年   1篇
  1952年   1篇
排序方式: 共有1415条查询结果,搜索用时 0 毫秒
41.
Amod  Ayush  Pahal  Sonu  Choudhary  Princy  Gupta  Ayushi  Singh  Sangeeta 《Biotechnology letters》2022,44(7):879-900
Biotechnology Letters - Hepatocellular carcinoma (HCC) is the uncontrolled growth of hepatocytes which results in nearly 5 million deaths worldwide. Specific strategies have been developed to treat...  相似文献   
42.
Plant Cell, Tissue and Organ Culture (PCTOC) - In vitro adventitious roots were induced from leaves of Valeriana jatamansi to assess their potential as a sustainable alternative to extract...  相似文献   
43.

Tylophora indica (Burm.f.) Merrill. is a pharmacologically important plant, popular for alkaloidal and non-alkaloidal richness. Large scale propagation of T. indica is difficult in the wild as the seeds are small and the frequency of germination is very poor. In the present study, the genome size estimation of in vitro regenerated (indirect, direct and somatic embryo mediated) T. indica was made by flow cytometric method. Clonal fidelity of the regenerants was assessed using a start codon targeted (SCoT) molecular marker. Initially, the explants were inoculated on Murashige and Skoog basal medium supplemented with various concentrations of plant growth regulators like 2,4-dichlorophenoxy acetic acid (2,4-D), Kinetin, 6-benzyl amino purine (BAP) and 1-naphthalene acetic acid either singly or in combinations. The highest callus induction frequency (87.75%) was obtained in 6.7 µM 2,4-D added MS medium which metamorphosed into progressive stages (globular, heart, torpedo, and cotyledonary) of embryos. Mature and healthy somatic embryos efficiently germinated into plantlets on 8.8 µM BAP?+?1.4 µM GA3 enriched MS medium. Histological and scanning electron microscopic study confirmed the above developing stages. The regenerated shoots were rooted best in 2.45 µM Indole-3-butyric acid supplemented solid MS medium. The plants were hardened and acclimatized with 90% survivability. The flow cytometric 2C DNA content of indirect, direct and somatic embryo derived plants was 1.896 pg, 1.940 pg and 1.926 pg respectively, very similar to the mother plant (1.928 pg). SCoT marker generated a high percentage of monomorphic bands (94%) revealing similarity with the mother plant, thus ensuring genetic fidelity. To the best of our knowledge, this is perhaps the first ever report of 2C DNA content estimation and SCoT marker based genetic homogeneity study in T. indica.

  相似文献   
44.
Molecular Biology Reports - Plant establishment, growth, development and productivity are adversely affected by abiotic stresses that are dominant characteristics of environmentally...  相似文献   
45.
46.
47.
48.
Bacteriorhodopsin (BR) is an integral membrane protein found in "purple membrane" (the Archaea cell membrane) mainly in Halobacteria. This protein absorbs green light (wavelength 500-650 nm, with the absorption maximum at 568 nm) and converts it into an electrochemical gradient. This gradient in turn is used for ATP production. The ability of BR to convert light energy into chemical energy or sunlight into electricity has been used in different applications mainly optical appliances but also for therapeutic/medical applications and research. This review surveys some of these applications that have been patented in the last five years.  相似文献   
49.
50.
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