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   2636篇
  免费   123篇
  2024年   6篇
  2023年   13篇
  2022年   42篇
  2021年   89篇
  2020年   47篇
  2019年   53篇
  2018年   61篇
  2017年   62篇
  2016年   93篇
  2015年   97篇
  2014年   156篇
  2013年   191篇
  2012年   247篇
  2011年   232篇
  2010年   130篇
  2009年   126篇
  2008年   149篇
  2007年   148篇
  2006年   155篇
  2005年   103篇
  2004年   104篇
  2003年   104篇
  2002年   100篇
  2001年   18篇
  2000年   10篇
  1999年   13篇
  1998年   31篇
  1997年   14篇
  1996年   6篇
  1995年   15篇
  1994年   8篇
  1993年   10篇
  1992年   13篇
  1991年   16篇
  1990年   5篇
  1989年   7篇
  1988年   8篇
  1987年   8篇
  1986年   5篇
  1985年   7篇
  1984年   12篇
  1983年   5篇
  1982年   9篇
  1981年   5篇
  1980年   6篇
  1979年   5篇
  1976年   2篇
  1973年   4篇
  1972年   4篇
  1965年   1篇
排序方式: 共有2759条查询结果,搜索用时 15 毫秒
41.
The genetic transformation of plants is an important biotechnological tool used for crop improvement for many decades. The present study was focussed to investigate various factors affecting genetic transformation of potato cultivar ‘Kufri Chipsona 1’. It was observed that explants pre-cultured for 2 days on MS2 medium (MS medium containing 10 µM silver nitrate, 10 µM BA, 15 µM GA3), injured with a surgical blade and co-cultivated with Agrobacterium tumefaciens strain EHA105 [O.D600 (0.6)] for 2 days results in maximum transient β-glucuronidase (GUS) expression. The addition of 100 µM acetosyringone in MS2 medium also increased rate of transient GUS expression in both the explants. Clumps of putative transgenic shoots were regenerated using the optimised culture conditions from leaf and internodal explants. The stable integration of T-DNA was established using histochemical staining for GUS and amplification of DNA fragment specific to nptII and uidA genes. Within the clumps, around 67.85% of shoots showed uniform GUS expression in all the tissues and about 32.15% shoots show intermittent GUS expression establishing chimeric nature. Uniform GUS staining of the tissue was used as initial marker of non-chimeric transgenic shoots. Quantitative expression of nptII transgene was found to be directly proportional to uniformity of GUS staining in transgenic shoots. The present investigation indicated that manipulation of culture conditions and the medium composition may help to get transgenic shoots with uniform expression of transgene in all the tissues of potato cultivar ‘Kufri Chipsona 1’.  相似文献   
42.
Journal of Plant Biochemistry and Biotechnology - Caseinolytic protease (Clp)/Hsp100 proteins are members of the AAA+ (ATPase associated with a variety of cellular activities) family of proteins...  相似文献   
43.
44.
Molecular Biology Reports - RUNX1T1 is extensively studied in the context of AML1-RUNX1T1 fusion protein in acute myeloid leukemia. Little is known about the function of RUNX1T1 itself, although...  相似文献   
45.
Biochemical Genetics - Misleading identification and subsequent publications on biological, molecular, and aquaculture data of mangrove mud crab (genus Scylla de Hann 1833) is a major concern in...  相似文献   
46.
A new species of the genus Cirrhimuraena (Anguilliformes: Ophichthidae), Cirrhimuraena indica sp. nov., is described based on eight specimens collected from the Paradip (Odisha) and Petuaghat harbours (West Bengal) along the Bay of Bengal. The species is distinct in having the upper jaw fringed with 16–17 cirri before posterior nostril and 4–5 in between the anterior and posterior nostrils on the side; dorsal fin originates above the level of gill opening, predorsal length is 9.3–10.9 in total length; the head is relatively large, the length is 9.3–9.8 in total length; no infraorbital pores are observed between the nostrils; teeth are numerous, small, conical and in bands on each jaw; pores are present before the gill opening 10–11 and before anus 47–48; pectoral-fin length is 2.4–2.8 in head length; predorsal vertebrae are 8–10, pre-anal vertebrae 43–47 and total vertebrae 164–169. In the maximum likelihood tree analysis for COI gene, the new species belongs to the same clade as the other congener of Cirrhimuraena chinensis and is separated from the species morphologically and genetically.  相似文献   
47.
Extremophiles - Technological advances in the field of life sciences have led to discovery of organisms that live in harsh environmental conditions referred to as extremophiles. These organisms...  相似文献   
48.
International Journal of Peptide Research and Therapeutics - The conopeptides are the conotoxin of Conus loroisii have wide applications in drug development. This work emphasizes the isolation and...  相似文献   
49.
Atherosclerosis is a chronic inflammatory disease arising due to an imbalance in lipid metabolism and maladaptive immune response driven by the accumulation of cholesterol-laden macrophages in the artery wall. Interactions between monocytes/macrophages and endothelial cells play an essential role in the pathogenesis of atherosclerosis. In our current study, nitric oxide synthase 1 (NOS1)-derived nitric oxide (NO) has been identified as a regulator of macrophage and endothelial cell interaction. Oxidized LDL (OxLDL) activates NOS1, which results in the expression of CD40 ligand in macrophages. OxLDL-stimulated macrophages produce some soluble factors which increase the CD40 receptor expression in endothelial cells. This increases the interaction between the macrophages and endothelial cells, which leads to an increase in the inflammatory response. Inhibition of NOS1-derived NO might serve as an effective strategy to reduce foam cell formation and limit the extent of atherosclerotic plaque expansion.  相似文献   
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