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101.
AM Osman S Boeren MG Boersma C Veeger IM Rietjens 《Canadian Metallurgical Quarterly》1997,94(9):4295-4299
The results of this study report the H2O2-driven microperoxidase-8 (MP8)-catalyzed dehalogenation of halophenols such as 4-fluorophenol, 4-chlorophenol, 4-bromophenol, and 2-fluorophenol in alcoholic solvents. In methanol, the conversion of the para-halophenols and 2-fluorophenol to, respectively, 4-methoxyphenol and 2-methoxyphenol, as the major dehalogenated products is observed. In ethanol, 4-ethoxyphenol is the principal dehalogenated product formed from 4-fluorophenol. Two mechanisms are suggested for this MP8-dependent alkoxylating dehalogenation reaction. In one of these mechanisms the oxene resonant form of compound I of MP8 is suggested to react with methanol forming a cofactor-peroxide-alkyl intermediate. This intermediate reacts with the reactive pi-electrons of the substrate, leading to the formation of the alkoxyphenols and the release of the fluorine substituent as fluoride anion. 相似文献
102.
103.
In the OHH, during the years 1969 to 1974, 28 patients were operatively treated because of delayed callusformation or pseud-arthrosis, following a fracture of the shaft of the humerus. It was possible to inquire about and to re-examine 20 patients. The operative treatment had, when possible been achieved by osteosynthesis through plates (25 cases). Each of the so treated cases lead to healing of the bone, additional nerve lesion did not in one case occur because of the operation. Objectively seen, there existed in 7 patients a slight, final restriction of movements, for the abduction and outside rotation in the shoulder joint. 6 patients complained of being sensitive to weather changes. The different treatment method of the fracture of the humerus and pseudarthrosis was discussed. 相似文献
104.
MG Duncan 《Canadian Metallurgical Quarterly》1993,46(5):150-151
105.
MA Blom MG van Twillert SC de Vries F Engels CE Finch R Veerhuis P Eikelenboom 《Canadian Metallurgical Quarterly》1997,777(1-2):210-218
Epidemiological studies have shown that steroidal as well as non-steroidal anti-inflammatory drugs lower the risk of developing Alzheimer's Disease (AD). A suppressive effect of these anti-inflammatory drugs on local inflammatory events in AD brains has been suggested, however the mechanisms responsible are still unknown. In this study we investigated at cellular level the influence of two anti-inflammatory drugs-dexamethasone and indomethacin--and an experimental specific cyclooxygenase-2 inhibitor, BF389, on the production of the pro-inflammatory cytokine IL-6 and the inflammatory mediator PGE2 by human astrocytes. Two human post-mortem astrocyte cultures (A157 and A295) and astroglioma cell lines (U251 and U373 MG) were found to secrete considerable amounts of IL-6 upon stimulation with IL-1beta. The glucocorticoid dexamethasone inhibited the IL-1beta-activated release of IL-6 from the postmortem astrocyte cultures A157 and A295 and from the astroglioma cell lines. The non-specific cyclooxygenase inhibitor indomethacin and BF389 only suppressed the IL-6 release by post-mortem astrocyte culture A157. This post-mortem astrocyte culture was found to produce large amounts of PGE2 upon stimulation with IL-1beta, whereas in the supernatants of the postmortem astrocyte culture A295 and the astroglioma cell lines, low PGE2 concentrations were detected. Addition of exogenous PGE2 prevented the inhibitory effect of indomethacin and BF389 on the IL-1beta-activated IL-6 release from A157 astrocytes and largely potentiated the IL-1-induced release of IL-6 from all astrocytes/astroglioma cells tested. Dexamethasone also inhibited the PGE2 release from the astrocytes and astroglioma cells, however the inhibitory effect of dexamethasone on the IL-1beta-activated IL-6 release could not be prevented by the addition of PGE2. The observed reduction of IL-6 and/or PGE2 from astrocytes may be involved in the mechanism underlying the beneficial effects of these drugs in AD. 相似文献
106.
107.
A novel electrophoretic method for the analysis of oligosaccharides using DNA sequencer technology is illustrated using malto-oligosaccharide distributions obtained following isoamylase digestion of glycogen, wheat starch and potato starch. The debranched starches were derivatized at the reducing and with the charged fluorophore 8-amino-1,3,6-pyrenetrisulfonic acid (APTS). This highly reproducible method provides baseline resolution of oligomers from chain lengths of 3 to more than 80 glucose units, and exhibits high sensitivity with detection thresholds of one femtomole per resolved band. In addition, the reductive amination procedure attaches a single fluorophore per oligosaccharide, allowing calculation of the results on either a mass or a molar basis. The efficacy of the method is illustrated through the determination of the profile of individual oligosaccharides of chain length with a degree of polymerization (DP) < 80, derived from loading less than 15 ng per analysis of glycogen, wheat and potato starches. While the results obtained were superior in resolution and sensitivity to previously reported observations using a range of techniques, they were nonetheless consistent with the overall differences between these polysaccharides. The resolution, sensitivity, reproducibility and high throughput of the method provides substantial advantages over existing methods for the analysis of linear oligosaccharide chain length distributions. 相似文献
108.
Social support and coping strategies as mediators of adult adjustment following childhood maltreatment 总被引:1,自引:0,他引:1
Structural equation modelling (SEM) was used to examine whether coping efforts and social support mediate the long-term sequelae of child maltreatment. The hypothesized SEM fit the data well and indicated that the association between previous childhood sexual and physical maltreatment and current psychological adjustment appeared to be strongly mediated by social support and coping strategies. In this sample of 302 female and male university students, most of whom reported at least one episode of childhood maltreatment, perceived social support and ways of coping with earlier maltreatment appeared essential to an understanding of the relationship between childhood maltreatment and later adjustment. 相似文献
109.
Inconsistent findings from recent mortality studies of workers exposed to magnetic fields have led to calls for more detailed understanding of exposure distributions and metrics in various industries. The authors undertook personal monitoring at an automobile transmission plant to (a) learn if magnetic field exposure differences were present, (b) make assignments for a brain cancer study, and (c) compare two exposure indices. A wide range of average exposures occurred (i.e., 0.016-4.6 microtesla). Within-day variability was also large, and it reached 4 orders of magnitude for some workers. Unexpectedly, demagnetizers were found among the strong sources that contributed to elevated exposures. The authors used conventional summary measures to assign job groups to exposure categories, and they used a new index of exposure irregularity to make alternative assignments. These new assignments appeared to differ from the original ones with respect to work time in each exposure group (i.e., 54% of the work time fell into different exposure categories). 相似文献
110.
High levels of interleukin 6 (IL-6) have been found in the brain tissue or cerebrospinal fluid (CSF) in several CNS disorders including Alzheimer's disease, AIDS dementia complex, multiple sclerois, stroke, Parkinson's disease, traumatic brain injuries, brain tumors and CNS infections. In these diseases, IL-6 is also found in blood showing that CNS conditions can elicit a peripheral immune response. A direct secretion of IL-6 from brain to blood has been shown to be a major mechanism by which the brain activates peripheral metabolic, endocrine and immune responses. However, this communication is not straightforward and other regulatory mechanisms are likely to be there. Several lines of evidence obtained in the laboratory have shown that the brain significantly modulates IL-6 production in the periphery. Evidence will be given that: (i) central inflammatory stimuli efficiently induce peripheral IL-6; (ii) central opioids are effective modulators of peripheral IL-6, and (iii) the sympathetic nervous system represents an inhibitory pathway to peripheral IL-6. 相似文献