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11.
Yoshio Umezawa 《化学:亚洲杂志》2006,1(3):304-312
Lately, scientists have explored approaches to developing fluorescent and/or bioluminescent indicators to pinpoint cellular processes in single living cells. These analytical methods have become a key technology for visualizing and detecting what was otherwise unseen in live cells. The target signaling included second messengers, protein phosphorylations, protein–protein interactions, and protein localizations. 相似文献
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Three four-step enantiospecific syntheses of different diastereomers of AES, a new biodegradable chelating agent, are described. The stereocenters in each of the isomers are accessible from l- and d-malic and aspartic acids. 相似文献
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The field of medicinal inorganic chemistry is rapidly advancing. In particular organometallic complexes have much potential as therapeutic and diagnostic agents. The carbon‐bound and other ligands allow the thermodynamic and kinetic reactivity of the metal ion to be controlled and also provide a scaffold for functionalization. The establishment of structure–activity relationships and elucidation of the speciation of complexes under conditions relevant to drug testing and formulation are crucial for the further development of promising medicinal applications of organometallic complexes. Specific examples involving the design of ruthenium and osmium arene complexes as anticancer agents are discussed. 相似文献
15.
When comparing an urban system to an elasto-plastic lattice, an analogy to the solid state of matter can be exploited using the concepts of the band theory similarly. Thereafter, the population dynamics – in a region of certain stability in the state space and within appropriate energy bands – can be described in terms of Cellular Automata, with two mobile agents or pseudo particles: the inhabitant (representative of an average individual) and the recurson (representative of its multidimensional resources). As in the solid state, transition rules take the form of two coupled transport equations, comprising the terms equivalent to the generation-recombination and circulation processes. The first process can be compared to a predator–prey growth model, typical of Ecology; whereas the circulation process – composed of a drift component and a diffusion component – should be compared to the concentration-sprawl demographic balance seen in urban occupation and dynamics. Thus, it needs to be defined and determined an urban potential function, an equivalent population charge, mobility and diffusion parameters, as well as net growth factors. This analogy, discussed within the context of a case study for Great Mendoza, plausibly explains the varied growth rates of the political departments, as well as the principal urban trends for spatial occupation. 相似文献
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以氯化锌、铁氰化钾(含有整合剂)的水溶液为原料,合成了铁锌双金属氰化物(DMC)催化剂。为获得高活性的DMC催化剂,需将叔丁醇 、多元醇螯合剂螯合至其结构中,用XRD、XPS等分析手段,对铁锌DMC催化剂的结构与活性进行分析表征。实验发现,DMC催化剂的晶体结构与螯合剂密切相关,螯合剂能显著降低DMC催化剂的结晶程度,从而提高DMC催化剂的活性。同时,氯化锌过量也有利于DMC催化剂活性的提高。并表征了相关DMC催化剂的活性中心。 相似文献
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R. D. Rakhimov E. R. Milaeva O. V. Polyakova K. P. Butin 《Russian Chemical Bulletin》1994,43(2):289-292
A procedure for the alkylation of metallic mercury by (dimethylglyoximato)butylcobalt(III) electrochemically generated in the presence of butyl bromide is proposed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 309–312, February, 1994. 相似文献
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In the recent years, the role of specific membrane active agents in the electrofusion process has started to draw attention, and it has been found that the presence of various substances in the cell medium can affect the fusion process either in a positive or negative way. In this work, the effect of several proteins, bivalent cations and antibiotics was tested with respect to their ability to protect intact erythrocytes from hemolysis and facilitate the fusion process. The effect of different sugars was also studied. Among the different proteins, pronase and proteinase were found to be the most effective. With respect to bivalent cations, Ca2+ and Mn2+ were more effective while Mg2+ was less important. From the antibiotics, penicillin caused a negative effect while streptomycin acted positively. Finally, glucose medium was found to be the most effective compared to all sugars tested. The results indicated that there are strong differentiations of the induced effects caused by each substance, and some possible mechanisms of action of these agents on the erythrocyte membrane were discussed. 相似文献