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   37篇
  免费   0篇
  国内免费   6篇
  2018年   1篇
  2017年   1篇
  2015年   1篇
  2014年   1篇
  2013年   3篇
  2012年   3篇
  2005年   2篇
  2004年   1篇
  2002年   1篇
  2001年   2篇
  2000年   2篇
  1999年   1篇
  1996年   1篇
  1992年   1篇
  1989年   1篇
  1987年   2篇
  1986年   1篇
  1984年   1篇
  1979年   2篇
  1978年   1篇
  1977年   2篇
  1976年   1篇
  1974年   5篇
  1973年   1篇
  1969年   2篇
  1968年   1篇
  1965年   1篇
  1964年   1篇
排序方式: 共有43条查询结果,搜索用时 31 毫秒
31.
金翅夜蛾亚科Plusiinae的研究   总被引:1,自引:0,他引:1  
周尧  卢筝 《昆虫学报》1974,(1):66-82
金翅夜蛾亚科(Plusiinae)是夜蛾科中一个显著的类群,从眼的睫毛,M_2的存在与前翅通常具有金银斑可以认识。但是不同属、种在外形上区别极少,所以如果不根据生殖器,要正确鉴定所有的属种,几乎是不可能。 这一亚科全世界已记载的约230余种,其分布于古北区的有107种。中国已记载的共70种。陕西省已有记载的只有6种,可能分布到的约21种。1963年朱弘复、陈一心二同志在《中国经济昆虫志(第三册)鳞翅目夜蛾科(一)》一书中记述了11种,提到其中5  相似文献   
32.
33.
Multiple Myeloma (MM) is a haematologic malignancy characterized by the accumulation of clonal plasma cells in the bone marrow. Over the last 10–15 y the introduction of the proteasome-inhibitor bortezomib has improved MM prognosis, however relapse due to bortezomib-resistance is inevitable and the disease, at present, remains incurable. To model bortezomib-resistant MM we generated bortezomib-resistant MM cell lines (n = 4 ) and utilised primary malignant plasma cells from patients relapsing after bortezomib treatment (n = 6 ). We identified enhanced Bruton''s tyrosine kinase (BTK) activity in bortezomib-resistant MM cells and found that inhibition of BTK, either pharmacologically with ibrutinib (0.5 μM) or via lenti-viral miRNA-targeted BTK interference, re-sensitized previously bortezomib-resistant MM cells to further bortezomib therapy at a physiologically relevant concentration (5 nM). Further analysis of pro-survival signaling revealed a role for the NF-κB p65 subunit in MM bortezomib-resistance, thus a combination of BTK and NF-κB p65 inhibition, either pharmacologically or via further lenti-viral miRNA NF-κB p65 interference, also restored sensitivity to bortezomib, significantly reducing cell viability (37.5 ± 6 .9 %, ANOVA P ≤ 0 .001). Accordingly, we propose the clinical evaluation of a bortezomib/ibrutinib combination therapy, including in patients resistant to single-agent bortezomib.  相似文献   
34.
The lipopolysaccharides (LPS) from Escherichia coli rough mutant strains F470 (R1 core type) and F576 (R2 core type) were deacylated yielding in each case a mixture of oligosaccharides with one predominant product which was isolated using high-performance anion-exchange chromatography. In addition, one oligosaccharide present in minor quantities was isolated from LPS of E. coli strain F576 (R2 core type). The structures of the oligosaccharides were determined by chemical analyses and NMR spectroscopic experiments. Furthermore, de-O-acylated and dephosphorylated LPS preparations were investigated by fast-atom bombardment and collision induced dissociation tandem mass spectrometry. The combined data allow us to deduce the following carbohydrate backbones of the E. coli R1 and R2 core types which share the following structure (Scheme 1): but differ in the substituents R1 and R2 which for the R1 core type are predominantly: and to a minor extent: and for the R2 core type predominantly: and to a minor extent: in which all sugars are d-pyranoses (l,d-Hep, lglycerodmanno-heptopyranose; P, phosphate).  相似文献   
35.
36.
An incoherent Thomson scattering system for observing local unsteady cavities that form in a turbulent plasma in the course of Langmuir collapse is described. Using this diagnostics, the density cavities in a laboratory plasma with developed strong Langmuir turbulence were directly observed for the first time and their spatial and temporal characteristics were determined.  相似文献   
37.
Abstract

New nucleoside analogues on the basis of 4(R), 5(R)-dihydroxymethy1-2-methyl-1,3-dioxoiane have been prepared. Alkylation of thymine, adenine and N2 -palmitoyl-guanine with 2-bromomethyl-4(R),5(R)-dibenzyloxymethyl-1,3-dioxolane followed by separation of regio isomers by adsorption chromatography and deprotection yielded the desired chiral nucleoside analogues. The structures of thus prepared compounds were confirmed by UV and PMR spectroscopy. The obtained compounds 11 have no anti-HIV and ant i herpetic activity and are not cytotoxic.  相似文献   
38.
39.
40.
The over-damped relaxation of elastic networks constructed by contact maps of hierarchically folded fractal (crumpled) polymer globules was investigated in detail. It was found that the relaxation dynamics of an anisotropic fractal globule is very similar to the behavior of biological molecular machines like motor proteins. When it is perturbed, the system quickly relaxes to a low-dimensional manifold, M, with a large basin of attraction and then slowly approaches equilibrium, not escaping M. Taking these properties into account, it is suggested that fractal globules, even those made by synthetic polymers, are artificial molecular machines that can transform perturbations into directed quasimechanical motion along a defined path.  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