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41.
The present piece of research studied the spontaneous alpha rhythm of the human brain by combining the use of a whole-cortex neuromagnetometer and Magnetic Resonance Imaging. Single trials of spontaneous brain activity were recorded from ten human subjects asked to rest, with their eyes either closed or open, in relaxed wakefulness. MEG measurements were conducted over a period of one and a half years. The replicability of the results was confirmed for eight subjects out of ten. For three subjects, the alpha rhythm did not show any reductions due to the opening of the eyes. Both field map pattern and location of the estimated source were persistently stationary during each of the bursts of oscillations of the alpha rhythm. Dipoles were concentrated in clusters, indicating the existence of several spatially distributed sources. The calcarine fissure, the parieto-occipital sulcus and the surrounding occipital and parieto-occipital areas were identified as cortical sites of the brain where the alpha rhythm may originate. For four subjects, the majority of the sources were located near or in the calcarine fissure, while for five subjects, they were located near or in the parieto-occipital sulcus and for the remaining subject they were equally divided between the two generation sites. 相似文献
42.
Atsushi Kikkawa Toshikazu Takata Takeshi Endo 《Macromolecular chemistry and physics.》1991,192(3):655-662
Cationic polymerization of styrene in the presence of 1-(p-methoxybenzyl)tetrahydrothiophenium hexafluoroantimonate ( 3 ) as an efficient cationic initiator was investigated. 3 was synthesized in an excellent yield by the reaction of p-methoxybenzyl bromide with tetrahydrothiophene and the subsequent exchange of bromide ions for hexafluoroantimonate ions. In the polymerization of styrene, 3 acted as a potent thermally latent initiator which initiates the polymerization at a slightly higher temperature than room temperature, although no polymerization occurs at room temperature for 30 min. 3 is a much more active initiator than the previously reported benzylsulfonium salt 1 . The enhanced activity of 3 was also confirmed in the polymerization of glycidylb phenyl ether. 相似文献
43.
Experimental arthritis induced by continuous infusion of IL-8 into rabbit knee joints. 总被引:1,自引:1,他引:1 下载免费PDF全文
H Endo T Akahoshi A Nishimura M Tonegawa K Takagishi S Kashiwazaki K Matsushima H Kondo 《Clinical and experimental immunology》1994,96(1):31-35
To determine the roles of IL-8 in inflammatory synovitis, examination was made of the results of continuously injecting human recombinant IL-8 into the knee joints of New Zealand while rabbits. Recombinant human IL-8 was infused continuously into the joint cavity at 75 ng/h for 14 days by a polypropylene catheter connected to a mini-osmotic pump implanted in each rabbit. Infiltration of inflammatory cells into joint cavity and histopathological changes in synovial tissue were examined at 7 and 14 days following the start of infusion. The continuous infusion of IL-8 for 14 days led to severe arthritis characterized by apparent erythema and joint pain, the accumulation of leucocytes, infiltration of mononuclear cells in synovial tissue, and marked hypervascularization in the synovial lining layer. IL-8 may be a factor which can contribute to the inflammatory process of chronic arthritis by mediating leucocyte recruitment and hypervascularization in inflamed joints. 相似文献
44.
K. Yagita R. R. Matias T. Yasuda F. F. Natividad G. L. Enriquez T. Endo 《Parasitology research》1995,81(2):98-102
The isolation of two plasmind-like ciruclar DNAs, measuring 52 and 42 kbp, from anAcanthamoeba sp. from the Philippines has led to the demonstration of a bacterial endosymbiont occurring in this free-living amoeba. The 52-kbp band hybridized with a short sequence of cytochrome b gene and was identified as the mitochondrial DNA, whereas the 42-kbp band was identified as plasmid DNA of the bacterial symbionts on the basis of electron microscopy. The endosymbionts are gram-negative, rod-shaped bacteria measuring approximately 1.3×0.43 m and numbering about eight to ten cells per section. They are randomly distributed in both cysts and trophozoites and are surrounded neither by a phagolysosomal membrane nor by a clear or electrontranslucent region. The endosymbiont membrane appears to have a close association with ribosomes, which are seen to be more concentrated within the vicinity of the symbionts than elsewhere within the cytoplasm. Attempts to grow the symbionts and the amoebae separately have failed. 相似文献
45.
Yoshinori Seko Shigeru Ishiyama Toshiro Nishikawa Takeshi Kasajima Michiaki Hiroe Shin Suzuki Sugao Ishiwata Sachio Kawai Yuetsu Tanaka Miyuki Azuma Tetsuji Kobata Hideo Yagita Ko Okumura Ryozo Nagai 《Cardiovascular pathology》2002,11(3):166-170
BACKGROUND: T-cell-mediated myocardial damage is known to be involved in acute myocarditis and dilated cardiomyopathy. Recently, we found that tumor necrosis factor (TNF) ligand superfamily costimulatory molecules, especially 4-1BBL, played an important role in the myocardial damage of murine acute viral myocarditis. METHODS AND RESULTS: To investigate the roles for CD27L, CD30L, OX40L and 4-1BBL, which belong to TNF ligand superfamily, in the development of acute myocarditis and dilated cardiomyopathy, we analyzed the expression of these antigens in the myocardial tissues of patients with acute myocarditis and dilated cardiomyopathy. We also examined expression of the receptors for these molecules, CD27, CD30, OX40 and 4-1BB, which belong to TNF receptor superfamily, on the infiltrating cells. Strong expression of CD27L, CD30L and 4-1BBL and weak to moderate expression of OX40L was found in the cardiac myocytes of patients with acute myocarditis. Moderate expression of CD27L, CD30L and 4-1BBL and weak expression of OX40L was found on the cardiac myocytes of patients with dilated cardiomyopathy. Most of the infiltrating cells expressed CD27, CD30 and 4-1BB and a part of the infiltrating cells expressed OX40. CONCLUSIONS: Our findings suggest that expression of TNF ligand superfamily costimulatory molecules on cardiac myocytes may play a role in the cell-mediated myocardial damage in patients with acute myocarditis and dilated cardiomyopathy as in murine viral myocarditis. 相似文献
46.
A toxic substance (P-II fraction), fractionated from the pedicellariae of the sea urchinToxopneustes pileulus, dose-dependently caused the histamine release from rat peritoneal mast cells. The histamine release induced by P-II fraction increased with time, while compound 48/80 caused a more rapid histamine release. The dose-response curve for P-II fraction was studied with concentration 0.03–2.0 mg/ml. This reaction was dependent on Ca2+ and temperature. When glucose (5.5. mM) was omitted during the incubation step, the histamine release induced by P-II fraction was significantly reduced as compared to that of compound 48/80. Pyruvate reversed this reduction. On the other hand, the histamine release induced by P-II fraction was effectively potentiated by the addition of glucose (11.0 mM), but not that by compound 48/80. These results suggest that P-II fraction-induced histamine release differs from that of compound 48/80 disregards to the effects of glucose, because this histamine release appears to be more sensitive to the glycolytic pathway than compound 48/80-induced histamine release. 相似文献
47.
Chronic active Epstein-Barr virus (EBV) infection has been recognized as clonal non-neoplastic lymphoproliferative diseases. However, some reports of cases with a multiphenotypic expansion of EBV-infected lymphocytes give rise to questions of how EBV infects multiphenotypic lymphocytes and whether chronic active EBV infection is a truly monoclonal lymphoproliferative disease. We report two patients with chronic active EBV infection who showed expansion of multiphenotypic EBV-infected lymphocytes. EBV DNA was detected in CD4+ and CD8+ T cells and in B cells from pleural fluid of one patient and in T and B cells from a cervical lymph node of the other patient by polymerase chain reaction (PCR). Although real-time PCR showed that there were equally high loads of EBV genomes in CD4+ and CD8+ T cells from the pleural fluid, Southern blot hybridization with terminal repeats of the EBV genome showed a single band of the same molecular weight in three tissue samples from the patient. The results indicated biphenotypic expansions of CD4+ and CD8+ T cells infected with the same clone of EBV. Furthermore, bisulfite PCR analysis showed hypermethylated status in the Cp region in the two patients regardless of their cell populations. There has been a discrepancy between clonality and expansion of multiphenotypic EBV-infected lymphocytes. We speculate that lymphoid progenitor cells that have not differentiated into T and B cell progenitors are infected with EBV, resulting in clonal expansion of EBV-infected multiphenotypic cells. 相似文献
48.
S. Lindstrom A. Endo S. Sugita M. Pecoraro Y. Hiromoto M. Kamada T. Takahashi K. Nerome 《Archives of virology》1998,143(8):1585-1598
Summary. Matrix (M) and nonstructural (NS) genes of thirteen equine H3N8 and H7N7 influenza viruses were sequenced and analyzed from
an evolutionary point of view. The M and NS genes of H3N8 viruses isolated between 1989 and 1993 evolved into two minor branch
clusters, including isolates from Europe and the American continent, respectively. It was noteworthy to reveal that the nucleotide
sequences of the M and NS genes of an earlier American strain showed highest homology to those of recent European viruses.
“Frozen evolution” was observed in the M and NS genes of A/eq/LaPlata/1/88. It was also evident that the NS gene of an H7N7
virus from 1977 was very similar to that of a 1979-H3N 8 virus, while the M gene was closest phylogenetically to that of the
earliest H7N7 virus isolated in 1956. Furthermore, the M2 protein of A/eq/Newmarket/1/77 virus contained a carboxyl terminal
deletion of three amino acids. The evolutionary rates of the M and NS genes of H3N8 equine influenza viruses were estimated
to be 5.4 × 10−4 and 5.1 × 10−4 substitutions per site per year, respectively, which were slower than those of human viruses.
Received November 21, 1997 Accepted March 9, 1998 相似文献
49.
50.
Yoshinao Oda Masazumi Tsuneyoshi Hiroshi Hashimoto Toshimitsu Iwashita Masahiro Ushijima Sachio Masuda Yukihide Iwamoto Yoichi Sugioka 《Virchows Archiv : an international journal of pathology》1993,423(1):65-69
Primary rhabdomyosarcoma of bone is exceedingly rare. We present a case of rhabdomyosarcoma of the iliac bone in a 32-year-old male. Histologically, the tumour consisted mainly of a uniform proliferation of elongated spindle cells arranged in a herring bone pattern, simulating fibrosarcoma. Focally there was a conventional embryonal pattern with scattered rhabdomyoblasts possessing an eosinophilic cytoplasm. Immunohistochemical studies disclosed expression of muscle markers such as desmin and muscle-specific actin, in both the embryonal and spindle-cell areas and myoglobin only in the embryonal areas. Such histological features are unusual for classical embryonal rhabdomyosarcoma. The anatomical site and age of the patient are also atypical. 相似文献