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101.
Proteolysis and myelin breakdown: a review of recent histochemical and biochemical studies 总被引:9,自引:0,他引:9
Synopsis Proteins are important constituents of the myelin sheath and serve to maintain its structural integrity. One of the protein components is susceptible to tryptic digestion and may be regarded as a particularly vulnerable part of the myelin sheath. The initial events in myelin breakdown may involve disruption of lipid-protein attachments followed later by chemical degradation of released lipids.In Wallerian degeneration the activity of proteolytic enzymes increases by 12 hr after nerve section. Proteolytic enzyme activity increases in the prodromal phase of diphtheritic neuropathy. Extracts of degenerating nerve cause proteolysis of normal myelin with loss of trypanophilic basic protein and lipid; selective loss of basic protein occurs very early in Wallerian degeneration and has also been found in and around plaques of multiple sclerosis. Proteolytic activity is increased at the edges of active multiple sclerosis lesions. It has been shown that the basic encephalitogenic protein is susceptible to digestion by neural proteases, yielding an active encephalitogenic fragment.It is inferred from these collective observations that proteases play an important role in early myelin breakdown and may also be implicated in the pathogenesis of multiple sclerosis plaques by digesting basic protein, by releasing lipid from its attachment to such protein, and by liberating an active encephalitogenic peptide. The factors responsible for the activation and release of proteases remain unknown.Research Associate supported by the Multiple Sclerosis Society. 相似文献
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Developmental potential of single blastomeres of the rabbit egg 总被引:2,自引:0,他引:2
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A new glycolipid sulfate ester in Halobacterium cutirubrum 总被引:7,自引:0,他引:7
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Forrest H. Adams 《The Western journal of medicine》1959,90(3):213-216
The incidence of congenital heart disease is approximately 1 per cent of all live births. Approximately 60 per cent of patients who die of congenital heart disease do so at less than two years of age. Very few patients with such lesions live beyond 45 years at the very most. In about 70 per cent of patients who are born with cardiac anomalies, the lesions are either of kinds that are already being operated upon successfully or for which operations are now being attempted and often are helpful. 相似文献