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91.
S. Kawaguchi M.D. T. Yamamoto A. Samejima K. Itoh N. Mizuno 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1979,35(3):511-518
Summary Changes in cerebellothalamic projections in kittens after neonatal hemicerebellectomy were studied by the retrograde and anterograde horseradish peroxidase (HRP)-tract-tracing methods. The number of cerebellar nuclear neurons labeled retrogradely with HRP injected into the ipsilateral VA-VL complex of the thalamus was much more numerous in neonatally hemicerebellectomized kittens than in intact kittens. Presumed terminals of ipsilateral cerebellothalamic fibers labeled anterogradely with HRP injected into the cerebellar nuclei were also distributed more densely and extensively in the thalamic areas, especially in the VA-VL complex, of hemicerebellectomized kittens than in the thalamic areas of the control kittens. These results are in good accordance with those obtained from the previous electrophysiological study (Kawaguchi et al., 1979) and offer corroborating evidence for axonal sprouting of cerebellothalamic neurons after neonatal hemicerebellectomy. 相似文献
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93.
Masahito Katoh Yasushi Itoh Kazumasa Ogasawara Kiichi Kajino Hiroki Nishihori Akio Takahashi Naoto Matsuki Kazuya Iwabuchi Takato O. Yoshida Robert A. Good Kazunori Ono 《European journal of immunology》1996,26(5):976-980
In a previous study, we identified T cell receptor and major histocompatibility complex (MHC) contact sites on the pigeon cytochrome c p43-58 peptide. Positions 46 and 54 of p43-58 were shown to be the MHC-binding sites. Specific amino acids were identified on the MHC-binding sites which bound to the relevant I-A molecule. In the present study, using NOD (I-Ag7) mice, we established a T cell hybridoma, NOE33-1-2, specific for a p43-58 analog 46R50E54A with arginine (R) and alanine (A) at positions 46 and 54, respectively. Interestingly, NOE 33-1-2 recognized 46R50E54A in the presence of not only I-Ag7, but also I-Ad, s, u and v. In contrast to previous reports that promiscuous T cells were able to recognize peptide antigens with various HLA-DR or I-E molecules consist of monomorphic α and polymorphic β chains, the promiscuous T cell clone NOE33-1-2 recognized peptides with various I-A molecules lacking the monomorphic chain. 相似文献
94.
Tetsuo Itoh 《Pathology international》1968,18(2):207-225
In allogeneic immunity against tumors induced by methylcholanthrene in the W/KA strain rat, serum antibody agglutinated red blood cells of the W/KA strain rat. The allogeneic antiserum was cytotoxic to the lymphocyte, but not to the tumor cells induced by methylcholanthrene.
In vitro and in vivo studies of allogeneic immunization of tumor suggested that immune macrophages or histiocytes play a major role in the rejection of transplanted tumor. Direct adhesion of immune macrophages with target cells is necessary for destruction of allografted tumor.
In antitransplantation immunity of the syngeneic and autochthonous rat, there was no cytotoxic serum antibody demonstrable in so far as routine techniques were employed. However, this may not exclude the existence of specific serum antibody or non-cytotoxic reaction with target cells of specific serum antibody. On the other hand, immune macrophages were always cytotoxic to target tumor cells, thus showing tumor specifity.
Experiment in which diffusion chambers were inserted into syngeneic immune rats suggested the possible participation of a humoral factor which was released from the immune rats immediately after contact with target cells and transform normal macrophages to immunologically active macrophages. The ascites macrophages have the greatest effective cytotoxic action among the three types of cells. In allogeneic tumor immunity, one immune macrophage can damage one target tumor cell showing single hit interaction. ACTA PATH. JAP. 18: 207–225, 1968. 相似文献
In vitro and in vivo studies of allogeneic immunization of tumor suggested that immune macrophages or histiocytes play a major role in the rejection of transplanted tumor. Direct adhesion of immune macrophages with target cells is necessary for destruction of allografted tumor.
In antitransplantation immunity of the syngeneic and autochthonous rat, there was no cytotoxic serum antibody demonstrable in so far as routine techniques were employed. However, this may not exclude the existence of specific serum antibody or non-cytotoxic reaction with target cells of specific serum antibody. On the other hand, immune macrophages were always cytotoxic to target tumor cells, thus showing tumor specifity.
Experiment in which diffusion chambers were inserted into syngeneic immune rats suggested the possible participation of a humoral factor which was released from the immune rats immediately after contact with target cells and transform normal macrophages to immunologically active macrophages. The ascites macrophages have the greatest effective cytotoxic action among the three types of cells. In allogeneic tumor immunity, one immune macrophage can damage one target tumor cell showing single hit interaction. ACTA PATH. JAP. 18: 207–225, 1968. 相似文献
95.
Changes in endogenous gangliosides caused by phorbol 12-myristate 13-acetate (PMA, 162 nM) were examined using mouse cerebrum primary cultures. The total ganglioside content was significantly decreased by 25% and 40% in PMA-treated cultures compared to control cultures on days 1 and 8, respectively. In addition, changes in the pattern of ganglioside composition were also observed in which the percentage of GM1 and GD3 in total gangliosides was significantly increased and, in contrast, the percentage of GD1a and GT1b was reduced. Treatment of neurons with PMA induced the change of morphology. These results suggest that the decrease in the total ganglioside content and changes in ganglioside composition produced by long-term exposure to PMA are related to the appearance of neuronal cell aggregation and neurite fasciculation. 相似文献
96.
97.
98.
New techniques in immunochemical analysis were reviewed briefly. Introduction of these new techniques into routine tests has made test results more precise and informative than before. By using one of these techniques, time-resolved fluoroimmunoassay, serum concentrations of CA 50 were quantitated in various malignancies. Clinical usefulness of its quantitation was proved especially in the diagnosis of pancreatic cancer. 相似文献
99.
We recently reported a gene encoding the human CDw108, a glycosylphosphatidylinositol (GPI)-anchored membrane glycoprotein that is preferentially expressed on activated T lymphocytes and erythrocytes. The present study investigated the expression of CDw108 on various tissues and cells, particularly on T cells during development. The murine CDw108 cDNA was cloned initially, and it was highly homologous to the human CDw108 (88.0% or 89.3% similarity at the nucleotide or amino acid level, respectively) or identical to the murine semaphorin K1/Sema7A. The CDw108 mRNA was demonstrated in a few tissues including thymus and brain with the highest expression coming on day 7 in whole embryo followed by relatively consistent expression during development. Cell-surface expression of the CDw108 during T-cell development was further examined by flow cytometry in the human umbilical cord blood and thymus. It was preferentially expressed on a CD34+ stem cell population of umbilical cord blood, and CD3dull CD34+/- CD117 (c-kit)+ CD4bright CDbright cells in the thymus that are involved in the stage of positive selection. These results suggest the contribution of CDw108 in T-cell development, especially in the stage of positive selection in the thymus. 相似文献
100.
Tetsuya Kawashima Yoshiyuki Yokota Mitsuhiro Yokoyama Hiroshi Itoh 《Pathology international》1993,43(6):304-312
The pathomorphologic features of hypertrophic cardiomyopathy simulating dilated cardiomyopathy in the late stage (HCM-DCM) were compared with those of ordinary hypertrophic cardiomyopathy (HCM). Seven autopsied hearts with HCM-DCM and 11 with HCM were assessed quantitatively using an image analyzer. Unlike HCM, significant left ventricular enlargement and wall thinning were observed in HCM-DCM, and the percentage areas of massive fibrosis and disarray were significantly greater. In HCM-DCM, the disarray was distributed diffusely, whereas massive fibrosis was distributed more intensively in the ventricular septum and anterior wall than in the lateral and posterior wall. Narrowing of intramyocardial small arteries was observed more frequently in HCM-DCM, especially in the ventricular septum and anterior wall, than in HCM. These results suggest that the enlargement and wall thinning of the left ventricle in HCM-DCM are attributable to non-uniform progression of massive fibrosis, which is closely related to small-arterial lesions. 相似文献