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The purpose of the present study was to understand the concept of aggressiveness of children through an analysis of the relationship between aggressiveness and personality traits. A total of 1,206 elementary school children were enrolled in the study. In order to investigate the correlation, a path analysis was performed using multiple regression analyses in which 4 variables of aggressiveness (irritability, hostility, physical aggression and verbal aggression) were employed as dependent variables and 5 variables of personality traits (agreeableness, conscientiousness, emotionality, openness and extroversion) were used as independent variables. The results of the analysis indicated that significantly positivepath was observed from extroversion to all four variables of aggressiveness. Extroversion indicated especially strong influence on irritability and physical aggression. A significantly negativepath was observed from agreeableness to irritability and hostility. From conscientiousness, a negative path was observed towards physical aggression and a positive path towards verbal aggression. A significantly negative path was observed from emotionality only towards verbal aggression. It was assumed that each of the four inferior characteristics of aggressiveness of children had a complex nature to be influenced by multiple personality traits. 相似文献
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Reactive oxygen species (ROS) are often shown to damage cellular functions. The targets of oxidative damage depend on the nature of ROS produced and the site of generation. In contrast, ROS can also regulate signal transduction. In this case, ROS may either induce or enhance events, which lead to forward directions of cellular signaling. The consequences of regulation of signal transduction can be observed in physiological processes such as muscle contraction. Here, we discuss the concentration-dependent effects of superoxide anion radical (*O2-) on Ca2+ release from the cardiac sarcoplasmic reticulum (SR). Recent studies suggest that the ADP-ribosyl cyclase pathway, through its production of cyclic adenosine 5'-diphosphoribose (cADPR), may control Ca2+ mobilization in cardiac muscle cells. *O2- has dual effects that are concentration dependent. At low concentrations (nearly nanomolar levels), *O2- induces Ca2+ release by stimulating synthesis of cADPR, which requires calmodulin for sensitization of ryanodine-sensitive Ca2+-release channels (RyRC). At these low concentrations, *O2- is responsible for regulation of cellular signal transduction. At higher concentrations (micromolar levels), *O2- produces a loss in the function of calmodulin that is to inhibit RyRC. This results in an increase in Ca2+ release, which is linked to cell injury. The difference in the functions of low and high concentrations of *O2- may result in two distinct physiological roles in cardiac muscle Ca2+ signaling. 相似文献
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Toshiaki Maruyama Ichiro Saito Sachiko Miyake Hiroshi Hashimoto Kazuto Sato Hideo Yagita Ko Okumura Nobuyuki Miyasaka 《European journal of immunology》1993,23(9):2059-2065
Synovial T cells play a crucial role in the pathogenesis of rheumatoid arthritis (RA) synovitis. We have quantitatively analyzed the T cell receptor (TcR) variable (V) region gene repertoire of freshly isolated synovial fluid (SF) T cells, comparing it with that of peripheral blood (PB) T cells in RA. The TcR V gene repertoire of PB and SF T cells in RA and osteoarthritis was heterogeneous. In contrast, Vail in SF was expressed to a greater degree in three of five RA patients, and increased levels of Vp6, 1-3 were found in the SF of four of six RA, compared with paired PB. Of note, Vβ6, 1–3 was universally used in four RA patients with a disease duration of less than 10 years, irrespective of their HLA-DR types. This was in contrast to two other RA patients, suffering for more than 20 years, who showed different Vα and Vβ usages. β-chain sequence analysis in RA patients with a preference for Vβ6, 1–3 has shown that a few clones dominated in SF, whereas polyclonality was observed in PB. These findings suggest oligoclonal expansion of T cells in response to specific antigen(s) in the SF of these patients with RA of relatively short duration. Concomitant use of two hydrophobic amino acids, leucine and valine, in the Dβ region was noticeable among the predominant SF clones. These two amino acids might directly contact a peptide specific for the induction of synovitis in RA patients. TcR-directed therapy may, therefore, be useful for the treatment of early RA synovitis. 相似文献
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Evidence of the monoclonal composition of human endometrial epithelial glands and mosaic pattern of clonal distribution in luminal epithelium 总被引:8,自引:0,他引:8
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Tanaka M Kyo S Kanaya T Yatabe N Nakamura M Maida Y Okabe M Inoue M 《The American journal of pathology》2003,163(1):295-301
The endometrium is a highly regenerative tissue that plays a crucial role in implantation. We examined the clonal constitution of glandular cells as well as the luminal epithelium of this unique tissue. Using collagenase-based digestion techniques with microscopic manipulation, we isolated individual human endometrial glands and examined their clonality using a polymerase chain reaction-based assay for nonrandom X chromosome inactivation with an X-linked androgen receptor gene. Most of the glands analyzed were composed of monoclonal populations of epithelial cells and one of the glands exhibited a loss of heterogeneity in the androgen receptor gene. In addition, adjacent glands within a 1-mm(2) area shared clonality, suggesting that clonality of the luminal epithelium is regionally defined. The clonality of endometrium was further confirmed in a study of female mice that harbor the green fluorescent protein gene on either the maternal or paternal X chromosome. Fluorescent microscopy of uterine sections revealed that individual endometrial glands consisted completely of either fluorescent or nonfluorescent cells and that the surface epithelium exhibited a clear boundary between these cell types. These findings suggest that single or multiple stem cells with uniform clonality exist on the bottom of each endometrial gland and genetic alterations occurring in such cells may play a critical role in endometrial carcinogenesis. The possible association between area-specific X inactivation of the endometrial surface and the endometrial receptivity of embryo implantation remains to be clarified. 相似文献
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Michihito Ishizawa Hidetoshi Okabe Keiji Matsumoto Shigeru Morimoto Sinsuke Hukuda Tokuhiro Chano 《Journal of orthopaedic science》2021,26(4):660-665
BackgroundTo better understand the nature of magnetic resonance imaging (MRI) findings in schwannomas, especially in the “target sign” of these findings, the histopathological investigation was performed.MethodsThe MRI findings were correlated with histopathological features in 22 samples of schwannomas, which were mostly resected from the extremities. The histopathological analyses included alcian blue staining and immunohistochemical staining for S-100 protein, proliferating cell nuclear antigen (PCNA) and epithelial membrane antigen (EMA).ResultsSeven of the 22 samples of schwannomas of the extremities exhibited target signs including a peripheral zone of homogeneously high signal intensity and a central zone of heterogeneous signal intensity in T2-weighted images. Gadolinium-enhanced T1–weighted images demonstrated a central heterogeneous enhancement and a peripheral ring of homogeneously low signal intensity. Histopathologically, S-100 and PCNA were positive only in the central heterogeneous signal area. In contrast, EMA was only stained on the degenerative epi/perineurium in the peripheral zone.ConclusionIn schwannomas of the extremities showing target sign in T2-weighted images, histopathologically, the peripheral areas were suggested to be mucinous degeneration of the epineurium or perineurium, while the central areas were composed of truly neoplastic cells. 相似文献