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81.
82.
The kinetic occipital (KO) region in man: an fMRI study 总被引:10,自引:8,他引:2
Van Oostende S; Sunaert S; Van Hecke P; Marchal G; Orban GA 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(7):690-701
We used functional magnetic resonance imaging to explore, in individual
subjects, the properties of the kinetic occipital (KO) region, which
previous position emission tomography studies have shown to be involved in
the processing of kinetic boundaries. The KO region was significantly
activated in 23/25 subjects tested in the subtraction of uniform motion
from kinetic gratings. The KO region is genuinely specialized for
processing kinetic boundaries since it is significantly more activated by
kinetic gratings than by luminance-defined gratings, uniform motion or
transparent motion. This leaves only the kinetic boundaries, created by
discontinuities in motion direction, as the specific stimulus aspect,
activating the KO region. The KO region is anatomically and functionally
distinct from areas MT/V5, V3 and V3A. It also has minimal overlap with the
lateral occipital (LO) region. The selective activation of the KO region is
robust and relatively immune to changes in stimulus size, spatial frequency
and type of kinetic boundary. These results strongly argue for the view
that the KO region is a new, separate, functional region in human occipital
cortex.
相似文献
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目的探讨脑利钠肽(brain natriuretic peptide,BNP)与超声心动图在川崎病急性期及恢复期诊断中的临床意义。方法选取川崎病患儿35例为病例组,以发热、皮疹为主诉的肺炎支原体或病毒感染的48例患儿为对照组,测其急性期与恢复期脑利钠肽及左、右冠状动脉内径值,并做相关分析。结果川崎病患儿急性期脑利钠肽值明显高于恢复期,且差异有统计学意义;川崎病患儿恢复期冠状动脉内径值明显高于急性期,且差异有统计学意义。结论应用超声心动图检测冠状动脉扩张是在恢复期诊断川崎病的重要手段,而脑利钠肽可作为急性期诊断川崎病的生化指标之一。 相似文献
86.
Adhesion of sickle neutrophils and erythrocytes to fibronectin 总被引:2,自引:0,他引:2
The pathophysiology of vaso-occlusive crisis in sickle cell disease involves interactions among blood cells, plasma proteins, and vessel wall components. The initial goal of this work was to quantify the adhesion of sickle red blood cells (RBCs) to fibronectin immobilized on glass under both static and dynamic shear stress conditions. High-power microscopic inspection of static assay plates showed striking numbers of adherent neutrophils as well as RBCs. Sickle neutrophils and RBCs were significantly more adherent to fibronectin than the corresponding normal cells in static adhesion assays. Adhesion of both sickle neutrophils and sickle RBCs in dynamic adhesion assays was promoted by a period of static incubation preceding initiation of shear stress conditions. Adherent neutrophils remained attached at shear stresses up to 51 dyne/cm2; most adherent RBCs were attached at shear stresses up to 13 dyne/cm2, but detached at a shear stress of 20 dyne/cm2. Sickle neutrophil adhesion was enhanced significantly by autologous plasma. Elevated levels of plasma interleukin-6 (IL-6; but not IL-1 or IL-8) were found in 6 of 9 sickle cell disease samples examined, and elevated levels of tumor necrosis factor were found in 2 of 9 samples. Plasma IL- 6 levels correlated positively with both the number of sickle neutrophils adherent to fibronectin and the ability of sickle plasma to enhance adhesion of normal neutrophils to fibronectin. These data suggest possible roles for neutrophil activation and for fibronectin in mediating sickle neutrophil and RBC adhesion. 相似文献
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Hamilton JA; Whitty GA; Stanton H; Wojta J; Gallichio M; McGrath K; Ianches G 《Blood》1993,82(12):3616-3621
Macrophage colony-stimulating factor (M-CSF or CSF-1) and granulocyte- macrophage CSF (GM-CSF) have been shown to increase human monocyte urokinase-type plasminogen-activator (u-PA) activity with possible consequences for cell migration and tissue remodeling; because monocyte u-PA activity is likely to be controlled in part also by the PA inhibitors (PAIs) made by the cell, the effect of M-CSF and GM-CSF on human monocyte PAI-2 and PAI-1 synthesis was investigated. To this end, elutriation-purified human monocytes were treated in vitro with purified recombinant human M-CSF and GM-CSF, and PAI-2 and PAI-1 antigen and mRNA levels measured by specific enzyme-linked immunosorbent assays and Northern blot, respectively. Each CSF could enhance the protein and mRNA levels of PAI-2 and PAI-1 at similar concentrations for each product. This similar regulation of monocyte PAI expression in response to the CSFs contrasted with that found for the effects of lipopolysaccharide, transforming growth factor-beta and a glucocorticoid. Therefore, PAIs may be modulating the effects of the CSFs on monocyte u-PA activity at sites of inflammation and tissue remodeling. 相似文献
89.
该研究明确流程优化的相关定义;分析国内外相关研究的现状;研究医院门诊和社区门诊的差异;探讨社区门诊存在或潜在的问题;提出优化社区门诊护理流程的相关策略如:简化流程,规范流程,调整布局,加强信息化建设等,我们致力于建立完善、规范的社区门诊管理体系,形成科学、简洁的社区门诊护理流程。 相似文献
90.
酵母菌药用乳糖酶制备新方法 总被引:3,自引:0,他引:3
目的:建立一种简易的从酵母菌制备克鲁维酵母乳糖酶的方法.方法:在30L发酵罐中进行发酵,用对羟基苯甲酸酯进行细胞破壁,用超微过滤方法浓缩破壁液.结果:乳糖酶的收率可达到每毫升发酵液含11.4 ONPG单位.从酵终细胞中释放乳糖酶可达70%,每毫升牛奶中加入1.2 ONPG单位制备的液态乳糖酶可使牛奶中的乳糖水解率达到70%. 相似文献