全文获取类型
收费全文 | 98篇 |
免费 | 11篇 |
国内免费 | 6篇 |
专业分类
化学 | 109篇 |
综合类 | 2篇 |
物理学 | 4篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 6篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 5篇 |
2015年 | 5篇 |
2014年 | 6篇 |
2013年 | 9篇 |
2012年 | 5篇 |
2011年 | 6篇 |
2010年 | 3篇 |
2009年 | 4篇 |
2008年 | 8篇 |
2007年 | 3篇 |
2006年 | 8篇 |
2005年 | 4篇 |
2004年 | 4篇 |
2003年 | 7篇 |
2002年 | 2篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1998年 | 3篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1982年 | 1篇 |
排序方式: 共有115条查询结果,搜索用时 15 毫秒
61.
植物单拷贝短序列的染色体原位杂交的检出率一直很低.水稻BAC克隆作为一种大容量载体的基因组克隆因其独特的优点已被应用于水稻基因组研究.用生物素标记了两个水稻BAC克隆,这两个克隆分别含与抗稻瘟病基因Pi-5(t)、抗稻绿叶蝉基因Glh和抗稻黄萎病基因RTSV在连锁图中等位的cDNA标记RZ565和RZ262,并用其进行了水稻染色体原位杂交.它们分别被定位在水稻第四染色体长臂距着丝粒百分距离40%和短臂100%处.由于供杂交BAC克隆含与3种抗病基因等位的标记,因此这些克隆的位置也就是供测抗病基因的位置.杂交检出率由迄今沿用的质粒克隆探针杂交的10%以下提高到了46.8%和59.2%.检出染色体的号数与遗传图确定的染色体相符,证实了用BAC克隆进行染色体原位杂交的优越性,为广泛利用水稻BAC克隆进行单拷贝小片段基因的定位打下了基础. 相似文献
62.
Hollow polyelectrolyte microcapsules (PEMC) are prepared using layer-by-layer self-assembly of polyelectrolytes on melamine formaldehyde templates, followed by template dissolution, and subsequent coating with biotinylated polyethylene glycol-grafted liposomes. These potential site-specific carrier systems show a high specificity for NeutrAvidin binding and a strong resistance against unspecific protein binding. It is concluded that this design with NeutrAvidin as the outermost layer of such capsules provides an ideal platform for the biofunctionalization of PEMC as drug delivery systems or as artificial cell-like structures for biomimetic studies. 相似文献
63.
借助Discovery Studio(简称:DS)软件,探讨了分子对接中的刚性对接在课堂教学中的运用,促使学生对配体与受体间相互作用机制及其强弱关系有更感性的认识,进而提高课堂教学质量。同时,有利于学生在课后自行练习,深化对分子间非键作用的认识。 相似文献
64.
65.
A surface-enhanced Raman scattering(SERS) optical fiber sensor was prepared by the laser-induced deposition of Ag nanoparticle membrane on a silica optical fiber tip, which was applied to the real time SERS spectral monitoring on the biorecognition of biotin/avidin. The bioidentification of biotin/avidin was carried out through a indirect method, in which the bioidentification is based on the SERS response signal of a labeled dye(Atto610) after its fluorescence has been quenched totally by the deposited Ag nanoparticle membrane. By SERS monitoring the bioidentification process of biotin/avidin, it has been found that this recognition process is finished in 40 min. The lowest detection concentration of biotin is 1.0×10-7 mg/mL. This research is promising in the application of immunoassays on line and in vivo. 相似文献
66.
Six luminescent cyclometalated iridium(III)-dipyridoquinoxaline and -dipyridophenazine complexes [Ir(ppy)2(N-N)](PF6) (Hppy = 2-phenylpyridine; N-N = dipyrido[3,2-f:2',3'-h]quinoxaline, dpq (1); 2-n-butylamidodipyrido[3,2-f:2',3'-h]quinoxaline, dpqa (2); 2-((2-biotinamido)ethyl)amidodipyrido[3,2-f:2',3'-h]quinoxaline, dpqB (3); dipyrido[3,2-a:2',3'-c]phenazine, dppz (4); benzo[i]dipyrido[3,2-a:2',3'-c]phenazine, dppn (5); 11-((2-biotinamido)ethyl)amidodipyrido[3,2-a:2',3'-c]phenazine, dppzB (6)) have been designed as luminescent intercalators for DNA and probes for avidin. The structure of complex 4 has been studied by X-ray crystallography. The photophysical and electrochemical properties of the complexes have also been investigated. The binding of these complexes to double-stranded calf thymus DNA and synthetic double-stranded oligonucleotides poly(dA) x poly(dT) and poly(dG) x poly(dC) has been investigated by spectroscopic titrations. The interactions between the two biotin-containing complexes and avidin have been studied by 4'-hydroxyazobenzene-2-carboxylic acid (HABA) assays and emission titrations. 相似文献
67.
68.
Oliver Reimann Dr. Caroline Smet‐Nocca Prof. Dr. Christian P. R. Hackenberger 《Angewandte Chemie (International ed. in English)》2015,54(1):306-310
We present a novel strategy for the traceless purification and synthetic modification of peptides and proteins obtained by native chemical ligation. The strategy involves immobilization of a photocleavable semisynthetic biotin–protein conjugate on streptavidin‐coated agarose beads, which eliminates the need for tedious rebuffering steps and allows the rapid removal of excess peptides and additives. On‐bead desulfurization is followed by delivery of the final tag‐free protein product. The strategy is demonstrated in the isolation of a tag‐free Alzheimer's disease related human tau protein from a complex EPL mixture as well as a triphosphorylated peptide derived from the C‐terminus of tau. 相似文献
69.
70.
M. Kashif Ali Biswarup Sen Yaodong He Mohan Bai Guangyi Wang 《Molecules (Basel, Switzerland)》2022,27(8)
Media supplementation with exogenous chemicals is known to stimulate the accumulation of important lipids produced by microalgae and thraustochytrids. However, the roles of exogenous chemicals in promoting and preserving the terpenoids pool of thraustochytrids have been rarely investigated. Here, we realized the effects of two media supplements—mannitol and biotin—on the biomass and squalene production by a thraustochytrid strain (Thraustochytrium sp. ATCC 26185) and elucidated their mechanism of action. A significant change in the biomass was not evident with the exogenous addition of these supplements. However, with mannitol (1 g/L) supplementation, the ATCC 26185 culture achieved the best concentration (642 ± 13.6 mg/L) and yield (72.9 ± 9.6 mg/g) of squalene, which were 1.5-fold that of the control culture (non-supplemented). Similarly, with biotin supplementation (0.15 mg/L), the culture showed 459 ± 2.9 g/L and 55.7 ± 3.2 mg/g of squalene concentration and yield, respectively. The glucose uptake rate at 24 h of fermentation increased markedly with mannitol (0.31 g/Lh−1) or biotin (0.26 g/Lh−1) supplemented culture compared with non-supplemented culture (0.09 g/Lh−1). In addition, the reactive oxygen species (ROS) level of culture supplemented with mannitol remained alleviated during the entire period of fermentation while it alleviated after 24 h with biotin supplementation. The ∆ROS with mannitol was better compared with biotin supplementation. The total antioxidant capacity (T-AOC) of the supplemented culture was more than 50% during the late stage (72–96 h) of fermentation. Our study provides the potential of mannitol and biotin to enhance squalene yield and the first lines of experimental evidence for their protective role against oxidative stress during the culture of thraustochytrids. 相似文献