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71.
Abstract  The purpose of this study is to find the correlation between middle latency auditory evoked potentials (MLAEP) and sound activated single photon emission computed tomography (SPECT) studies. This study was performed on six normal right-handed volunteers with a mean age of 35.2 ± 7.6 years, using the split-dose technique. First, a SPECT study was performed on subjects in blinded, awake and silent states. After bilateral ears were stimulated with a click sound, MLAEP and a second SPECT study were performed. Subtraction of the first SPECT from the second SPECT revealed a statistically significant increase of cerebral blood flow (CBF) in the bilateral superior temporal region. Bilateral Na amplitudes of MLAEP had a statistically significant and good correlation with the percentages of CBF changes in the bilateral superior temporal region. The superior temporal cerebral blood flow activation can be expressed by electrophysiological activation. Moreover, correlation during the left Na components and left frontal and occipital lobe are discussed.  相似文献   
72.
Effects of activated charcoal and atropine for the removal of organophosphorus compounds, which remain in the gastrointestinal tract or have already been absorbed into the systemic circulation, were investigated in rats. Activated charcoal extensively adsorbed the organophosphates fenitrothion, tolclofos methyl, piperophos and salithion, and its immediate administration after oral ingestion of fenitrothion remarkably reduced serum fenitrothion levels, but had no effect on the serum levels of the compound which had been absorbed from the gastrointestinal tract. Thus, all of the organophosphorus compounds were poorly exsorbed (0.002-0.39% of the dose in 120 min) from the blood into the intestinal lumen probably due to their extensive protein binding and large distribution volumes. Atropine inhibited absorption of fenitrothion in the perfusion in-situ and also delayed the absorption of the compound in-vivo, but had no significant effect on exsorption of fenitrothion. The serum fenitrothion levels on treatment with both atropine and charcoal significantly decreased compared with those of the control. We conclude that, oral activated charcoal will not be able to enhance the elimination of organophosphorus compounds which have already been absorbed into the systemic circulation, but constitute a useful method for the removal of the compounds remaining in the gastrointestinal tract because of its excellent adsorptive capacity.  相似文献   
73.
Abstract: Over the last two years, a total colonoscopy was performed on 3,006 patients and 232 colorectal carcinomas were detected in these patients. Seventy one (30.6%) of the carcinomas were found to be early cancers. Eighteen (25.4%) of these 71 early cancers were minute (>5 mm) colorectal carcinomas of the flat or depressed type and they were resected endoscopically. More than half of them were accompanied by colonic polyps. Among the characteristic endoscopic features of flat and depressed early colorectal carcinomas are redness, fine granularity and defects of the innominate groove on the lesional surface. Another important finding is whitish annular mucosa surrounding the lesion. The gross appearance of these lesions was depression (3 lesions), depression with a marginal elevation (11 lesions), or flat (4 lesions). On histological examination, all the lesions were found to be well–differentiated intramucosal adenocarcinoma. It appears that depressed lesions with or without marginal elevation have a tendency to horizontal and vertical invasion, respectively. Moreover, it is thought that flat lesions are very early cancers that might later develop into depressed lesions with or without marginal elevation, or flat elevated lesions.  相似文献   
74.
A 62-year-old woman had multiple plasmacytomas in the skin and lymph nodes, without Bence-Jones protein or a monoclonal peak of serum immunoglobulins. Infiltrating plasmacytoid cells expressed cytoplasmic IgG (λ) and surface CD38, without any B-cell markers. There was no visceral or bone marrow involvement suggestive of multiple myeloma. Southern blot analysis of extracted DNA from the cutaneous lesions showed two rearranged bands with an immunoglobulin, but not a T-cell receptor, gene probe. The patient showed a poor response to chemotherapy, and died of bronchopneumonia. The clinical course and cytological features differentiate multiple cutaneous extramedullary plasmacytomas from solitary cutaneous extramedullary plasmacytoma and cutaneous lesions associated with tnultiple myeloma.  相似文献   
75.
Leiomyosarcoma in childhood is very rare. This report describes the immunohistochemical study of a gastric epithelioid leiomyosarcoma in a 14 year old girl. Microscopically, the tumor showed two distinct histological patterns within the same tumor: small epithelioid cells forming a lobular pattern and spindle-shaped cells forming interlacing fascicles, but no distinct border divided the two types of cells. Immunohistochemically, vimentin was positive in all tumor cells; a-smooth muscle actin, however, was negative in small epithelioid cells and positive in spindle-shaped cells. The data revealed that the tumor had components showing two stages of morphological and biochemical differentiation. This case indicates that leiomyosarcomas might lose smooth muscle actin during malignant transformation; or, alternatively, they might arise from a primitive type of smooth muscle cell and some of them could spontaneously differentiate into mature smooth muscle cells, expressing this actin.  相似文献   
76.
Abstract: We report a case of hemorrhagic gastric ulcer in which endoscopic injection of Histoacryl effectively achieved hemostasis. The patient was an 86-year-old woman with complaints of hematemesis and melena, and emergent endoscopic examination revealed fresh bleeding from the gastric ulcer. Neither endoscopic injection of Aethoxysklerol and ethanol nor clipping stopped the active bleeding, while the injection of Histoacryl produced an immediate hemostatic effect. Unfortunately, she died of pneumonia and heart failure seven days after this treatment. Autopsy revealed Histoacryl polymer localized in the gastric wall, but the gastric ulcer that had caused the massive bleeding was covered with exudate and the site of arterial rupture was unclear. The significant hemostatic effect of Histoacryl injection and the histological findings in this case suggest that this procedure may be useful for managing refractory hemorrhagic gastric ulcer.  相似文献   
77.
We describe a type of mild hypermethioninemia due to a point mutation in the MATA1 gene, which was inherited dominantly in a family. Three patients coming from the same family pedigree were detected by the presence of isolated hypermethioninemia on a mass-screening program. The measurement of methionine adenosyltransferase (MAT) activity in a patient's liver revealed a partial deficiency of hepatic MAT with a reduction in the Km for methionine. Single strand conformation polymorphism (SSCP) analysis and direct sequencing of the patients' genomic DNA revealed a G to A mutation at nucleotide 791 that converts Arg-264 to His (R264H) in one allele of MATA1 gene. The other allele was normal in all the patients examined. Gene tracking in the family revealed that the hypermethioninemia is associated with heterozygosity for the R264H mutation in the MATA1 gene.  相似文献   
78.
We have investigated the pharmacological properties of pteleprenine, a quinoline alkaloid, on contractile responses of the guinea-pig ileum and on inotropic responses of the canine left atrium. Although pteleprenine (0·1–1 μM) had no effect on the contraction of the ileum induced by acetylcholine at 10 μM it significantly inhibited acetylcholine-induced contraction of the ileum. Pteleprenine (0·1–10 μM) reduced nicotine induced-contraction of the ileum in a concentration-dependent manner yet had no maximum relaxant effect even at a concentration of 10 μM From Schild analysis the pA2 of pteleprenine on the guinea-pig ileum was found to be 6-6. The contraction of the ileum induced by 10 μM 1,1-dimethyl-4-phenylpiperazinium, a specific agonist of nicotinic acetylcholine. receptors, was concentration-dependently suppressed by 10 nM-10 μM pteleprenine. In contrast, 0.1–10 μM pteleprenine did not antagonize the acetylcholine- and nicotine-induced negative inotropic contractile responses of the canine left atrium. These results show that pteleprenine has inhibitory action against nicotinic acetylcholine receptors in the guinea-pig ileum but not in the canine left atrium. Our findings also suggest that pteleprenine might be a novel lead compound as a nicotinic receptor antagonist.  相似文献   
79.
In view of the fact that a repetition of the same behavior was manifested in over 60-year-old psychotic patients, we gave an opinion on stereotypy. We have recognized in those patients no verbigeration but only a stercotypically repeated behavior. These stereotypic movements were found in 20 cases, 17 of which showed a stereotypic masticating movement. This stereotypic mastication could, it. seems, belong to iteration. From the fact that the iteration appears in a serious demenia or a deteriorated state, wc dealt with stereotypy in association with a mentally deserted state. We believe that the stereotypy or iteration of aged psychotic patients can be understood neither psychopathologically as a problem of intentionality nor neurologically as that of localization of a lesion in the brain.  相似文献   
80.
The unfolding pathway of lysozyme was investigated by carrying out the computer simulation. Taking into account the simultaneous change of both the dihedral angles ø and of a residue, we explore the detailed features of the conformational energy profiles. The triangle distance map shows that the lysozyme molecule is divided into three domains, 1–40, 41–101 and 102–129 in amino acid residue numbers (referred to as the domains I, II and III, respectively). The calculated unfolding process indicates that in the early stage of unfolding domain III located at the C-terminal begins to be detached from the other two, and then domain I can be unfolded. The long-range interactions between domains I and III stabilize the whole molecule and give the cooperative nature of the folding. The calculated unfolding pathway of lysozyme is consistent with the folding pathway proposed by Anderson & Wetlaufer [J. Biol. Chem. (1976). 251 , 3147–3153] who identified the disulfide bondings in the early stage of the glutathione regeneration. A simplified treatment of unfolding for myoglobin is also discussed in the Appendix.  相似文献   
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