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81.
A L Nevmiatullin O N Vorob'eva A N Maianski? 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1985,(7):67-71
The neutrophil-stimulating properties of 38 S. aureus strains and 32 S. epidermidis strains were studied in the reaction of luminol-mediated chemiluminescence. All S. aureus strains and 29 S. epidermidis strains were found to possess neutrophil-stimulating activity, the mean activity index for S. aureus being significantly higher. The stimulating activity of the strains varied within a wide range (the variation coefficient was 120.0 +/- 21.9%) and did not correlate with the content of protein A in bacterial cells and the degree of their hydrophoby. The opsonization of staphylococci with normal human serum enhanced the neutrophil reaction 1.5- to 100-fold and simultaneously leveled out the chemiluminescence indices in experiments with different strains (the variation coefficient was 8.0 +/- 1.5%). The nature of the neutrophil-stimulating effect of staphylococci and its relationship to the exploratory reactions of phagocytes are discussed. 相似文献
82.
The effects of 5-hydroxytryptamine and 5-hydroxytryptophan on 86Rb+ efflux from prelabelled ob/ob-mouse islets were studied to better understand the cellular mechanisms underlying the effects of 5-hydroxytryptamine and 5-hydroxytryptophan on insulin release. 5-Hydroxytryptophan (4 mM) had no effect on 86Rb+ efflux either at a low (3 mM) or at a high (20 mM) d-glucose concentration, whereas 5-hydroxytryptamine (4 mM) stimulated 86Rb+ efflux at both glucose concentrations. These results indicate that 5-hydroxytryptamine may reduce glucose-induced insulin release by inhibiting early steps in the β-cell stimulus-secretion coupling. 相似文献
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—A resolution of the enhancement of protein synthesis in the visual cortex of rats during first exposure to light (Richardson and Rose , 1972) was achieved by polyacrylamide gel electrophoresis using a double-labelling technique. Differential incorporation of lysine was established between exposed and control animals in two fractions of the soluble proteins and seven fractions of the insoluble proteins. This suggests that exposure to a new experience of this type involves a specific effect on protein synthesis, rather than a general stimulation across all fractions. 相似文献
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