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101.
We examined fibroblast growth factor (FGF)-9 immunoreactivity in human hippocampal sections of Alzheimer's disease (AD). FGF-9 immunoreactivity was observed in dystrophic neurites of senile plaques in AD and control cases, in addition to the hippocampal and cortical neurons. The amyloid core and neurofibrillary tangles lacked immunoreactivity. FGF-9 immunoreactive astrocytes were conspicuous in AD brains. FGF-9 may be involved in the neuropathology of AD.  相似文献   
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A new type of permanent magnetic circuit with several prominent characteristics was developed and applied to the studies of oriented macromolecular assemblies by small-angle X-ray scattering using synchrotron radiation source.  相似文献   
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Charcot-Leyden crystals (CLC) are rarely described in tissue. Because of the derivation of CLC from eosinophils, and the antineoplastic functions that eosinophils effect, it is plausible that CLC in neoplastic tissue specimens may be significant. We recently encountered a case in which Hodgkin's disease and CLC were unexpectedly found. We reviewed 31 cases of Hodgkin's disease for CLC and sought relationships between CLC incidence and morbidity or mortality. While various grades of eosinophilia were represented, CLC were encountered only in the case reported. The role of eosinophils and CLC in Hodgkin's disease is enigmatic. With clinicopathologic correlations from additional patients, it may be determined that CLC play a role in the natural history or prognosis of Hodgkin's disease.  相似文献   
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Allelic loss studies have suggested that a glioma tumor suppressor gene resides in a 425-kb region of chromosome 19q, telomeric to D19S219 and centromeric to D19S112. Exon amplification of a cosmid contig spanning this region yielded four exons with high homology to a rat protein serine-threonine phosphatase from a cosmid approximately 100 kb telomeric to D19S219. Isolation of a near full-length cDNA from a human fetal brain cDNA library revealed a protein serine-threonine phosphatase with a tetratricopeptide motif, almost identical to human PPP5C (PP5) and highly homologous to rat PPT. Northern blotting demonstrated expression in most tissues, including brain. Primary and cultured gliomas were studied for genetic alterations in this gene using pulsed-field gel electrophoresis, routine Southern blots, and genomic DNA-and RNA-based single-strand conformation polymorphism analysis. Genomic alterations were were not detected in any of the gliomas, and all studied gliomas expressed the gene, suggesting that this phosphatase is not the putative chromosome 19q glioma tumor suppressor gene.  相似文献   
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Microstructure and mechanical properties of hot-pressed SiC-TiC composites   总被引:1,自引:0,他引:1  
Hot-pressed SiC-TiC composite ceramics with 0–100 wt% TiC have been investigated to determine the effect of composition (amount of TiC) on the elastic modulus, hardness, flexural strength and fracture toughness,K IC. The composites exhibited superior mechanical properties compared to monolithic SiC and TiC, especially in fracture toughness,K IC, value for 30–50 wt% TiC composite. The maximum values ofK IC and room-temperature flexural strength were 6 MPa m1/2 for a 50 wt % TiC and 750 MPa for a 30 wt% TiC composite, respectively. The observed toughening could be attributed to the deflection of cracks due to dispersion of the different particles. Although no third phases were detected by both TEM and XRD studies, an EDAX study and resistivity measurements indicated some possibility of solid solutions being present. The composites containing more than 30 wt% TiC, exhibited resistivity lower than 10–3 cm which is favourable for electro-discharge machining of ceramics.  相似文献   
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