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201.
Ten diether-type monoglycosyl and glycobiosyl glycerolipids, including 3-O-(4-O-β-D-galactopyranosyl-β-D-glucopyranosyl)-l,2,-di-O-n-tetradecyl-sn-glycerol, a synthetic analogue of lactosyl ceramide, were synthesized and their stereochemistry was assigned unambiguously by 13C NMR using the values of C-H one bond couplings. Their 13C NMR were further analysed to show the diagnostic α-effect of glycosylation in these compounds depending on the anomeric configuration of the glycosyl residue linked to C-3′-O atom.  相似文献   
202.
Sepsis is a major clinical challenge and septic encephalopathy is its nasty complication. The pathogenesis and underlying mechanisms of septic encephalopathy are not well understood. This study sought to fully characterize sepsis-associated biochemical and histopathological changes in brains of mice after cecal ligation and puncture, regarded as a highly clinically relevant animal model of polymicrobial sepsis. Real-time PCR analysis showed that gene expression levels of proinflammatory cytokines, including tumor necrosis factor-α and interleukin-1β, were significantly up-regulated in brain tissues from septic mice, but to a much lesser extent when compared with those in peripheral tissues such as lungs. Blood-brain barrier (BBB) permeability was significantly increased in septic mice, as determined by the measurement of sodium fluorescein and Evans blue content. Sepsis resulted in increases in NADPH oxidase activity and expression of p47phox and p67phox and up-regulation of inducible nitric oxide (NO) synthase in brains, indicating that superoxide, produced by NADPH oxidase, reacts with NO to form peroxynitrite, that maybe lead to the loss of BBB integrity. Light and electron microscopic examination of septic mouse brain showed serious neuronal degeneration, as indicated by hyperchromatic, shrunken, pyknotic, and electron-dense neurons. These histopathogical changes were prevented by treatment with the free radical scavenger edaravone. Together, these results suggest that sepsis can lead to rapid neurodegenerative changes in brains via free radical species production and possibly subsequent injury to the BBB. We may also provide a potentially useful therapeutic tool for treating septic encephalopathy.  相似文献   
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Several compounds related to helminthosporol (I), a natural plant-growth promoter, were prepared from I and their plant-growth regulating activities were examined together with those of the derivatives reported in the previous paper, using rice and lettuce seedlings. Among the compounds tested, helminthosporic acid (III) exhibited marked elongation effect to the shoot growth of rice and lettuce seedlings, whereas the effect of I was specific to the former. Results of the biological test are reported in details.  相似文献   
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A new compound was isolated from leaves of peanut. Its structure was determined as o-(malonylamino)benzoic acid on the basis of physicochemical evidences.  相似文献   
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—In order to study changes of the glycolytic-respiratory system and amino acid metabolism associated with blood flow disturbance, the cat brain perfusion was conducted with artificial blood containing [U-14C]glucose and the results were compared with those of standard perfusion keeping the cerebral blood flow at constant rate. The findings of the present study are briefly summarized: (1) In blood flow disturbance there was observed an accumulation of lactate just as seen in the low functional state observable in the standard perfusion. However the increase in relative specific activity of lactate was not so marked as the rise in cerebral lactate content, and this indicates that there is an increase of lactate production from substrates other than glucose as well as an increase of net flow of glucose carbon to lactate. (2) In blood flow disturbance relative specific activities of glutamate, aspartate, glutamine and respiratory CO2 were decreased as compared with those in the brain of high functional state. The relative specific activity of GABA in the reduced blood flow brain was at the same level as that of the brain at high functional state and it was higher than the relative specific activity of glutamate. (3) The relative specific activity and content of alanine were increased in the low function brain with standard perfusion.  相似文献   
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ATP-dependent Ca uptake of brain microsomes   总被引:1,自引:0,他引:1  
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