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991.
992.
T Kawamata T Taniguchi H Mukai M Kitagawa T Hashimoto K Maeda Y Ono C Tanaka 《Canadian Metallurgical Quarterly》1998,18(18):7402-7410
A possible role for a protein kinase, PKN, a fatty acid-activated serine/threonine kinase with a catalytic domain homologous to the protein kinase C family and a direct target for Rho, was investigated in the pathology of Alzheimer's disease (AD) using a sensitive immunocytochemistry on postmortem human brain tissues and a kinase assay for human tau protein. The present study provides evidences by light, electron, and confocal laser microscopy that in control human brains, PKN is enriched in neurons, where the kinase is concentrated in a subset of endoplasmic reticulum (ER) and ER-derived vesicles localized to the apical compartment of juxtanuclear cytoplasm, as well as late endosomes, multivesicular bodies, Golgi bodies, secretary vesicles, and nuclei. In AD-affected neurons, PKN was redistributed to the cortical cytoplasm and neurites and was closely associated with neurofibrillary tangles (NFTs) and their major constituent, abnormally modified tau. PKN was also found in degenerative neurites within senile plaques. In addition, we report that human tau protein is directly phosphorylated by PKN both in vitro and in vivo. Thus, our results suggest a specific role for PKN in NFT formation and neurodegeneration in AD damaged neurons. 相似文献
993.
994.
In this research we investigate the competence construct, its structure, and the interrelations among assessments of children's competence provided by different observers. These questions were investigated in a sample of 76 girls 8 to 11 years of age. The results of bivariate correlations showed that there were statistically significant relations of moderate size between subscales of the self-rated Perceived Competence Scale for Children (PCSC; Harter, 1982) and the maternal-rated Social Competence measure of the Child Behavior Checklist (CBC; Achenbach & Edelbrock, 1981, 1983). Two dimensions emerged from an interbattery factor analysis. The dimensions assessed interpersonal competencies and competencies in the academic-cognitive domains. Physical-athletic competencies were not found to define important dimensions for this sample of girls. We discuss suggestions about a differentiated consideration of competence and possible gender differences in the assessment of competence, along with two alternative models suggested by this work for studying the stress-buffering role played by competence measured from several perspectives. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
The configurational sequences of 1,2-unit in a series of hydrogenated syndiotactic 1,2-polybutadienes were investigated in relation to the sequence distribution of 1,2- and 1,4-units. The signals at 10.20–10.94 ppm were assigned to the methyl carbons in the isolated 1,2-unit, the 1,2-1,2 dyad sequence flanked by 1,4-unit, and the 1,2-1,2-1,2 triad sequence, in order of increasing magnetic field. The splittings due to the configurational sequences were observed in the signals, reflecting the dyad and triad sequences of the 1,2-unit, which were assigned by considering the relative intensity of the signals and also the chemical shifts of model polymers. 相似文献
996.
Regularization of hypersingular and nearly singular integrals in the potential theory and elasticity
V. Sladek J. Sladek M. Tanaka 《International journal for numerical methods in engineering》1993,36(10):1609-1628
Both the hypersingular and nearly singular integrals, which appear in the hypersingular boundary integralequations and integral representations of the secondary fields, respectively, are regularized by the application of the superposition principle. Two kinds of the non-singular formulations, namely, those with the strongly singular and weakly singular kernels, are presented in this paper. The formulations are given in terms of the relevant boundary quantities and the collocation at element junctions is possible. Two- and three-dimensional problems are analysed simultaneously in a unique way for either internal or external problems of the potential theory and elasticity. 相似文献
997.
The production of hydrogen from water by reduced tin oxide has been examined under various experimental conditions. It has been concluded that the reactive species decomposing water is metallic tin. The coexistence of SnO2 with metallic tin enhances the rate of hydrogen production remarkably. The effect of SnO2 has been ascribed to the enlargement of surface area of tin metal by its dispersion on the surface of SnO2. Solid additives such as Pd, Pt, WO3, CuO and CaO showed a large promoting effect for hydrogen production. The effect of the additives may be explained by increase in the surface area of tin metal or by the spill-over of the activated water by additives onto the surface of SnO2 or tin metal. 相似文献
998.
H Niiyama K Yamaguchi S Shimizu K Yokohata K Chijiiwa H Yonemasu M Tanaka 《Canadian Metallurgical Quarterly》1998,10(8):703-707
We report an unusual case of laryngomucocele occurring after subtotal laryngectomy. Laryngoceles generally have a congenital origin in a long-preexisting saccule, and their association with laryngeal carcinoma is well known. Laryngocele is usually favored by the increase of intraglottic pressure caused by the laryngeal carcinoma. However, an iatrogenic secondary laryngomucocele occurring after a surgical procedure is uncommon. We report in detail the physiopathologic conditions leading to the creation of this lesion. 相似文献
999.
1000.
The authors propose a new ARQ scheme suitable for image transmission over radio channels. The proposed scheme detects only serious degradation and so attains higher throughput performance than the conventional ARQ scheme 相似文献