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We identified novel 10 multi-cysteine peptides, namely Magi 7-16, from the spider Macrothele gigas by simple random cDNA screening of the venom gland. Mass analysis of the crude venom detected the mass numbers of the cross-linked forms of all peptides, confirming their presence in the venom. Magi 11, a C-terminus amidated peptide, was chemically synthesized and was indistinguishable from the native peptide proving the feasibility of the method for peptide identification. Moreover, toxicological assays showed diverse lethal or paralytic activities of these peptide toxins on mice and/or insects.  相似文献   
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The recognition of threatening faces is important for making social judgments. For example, threatening facial features of defendants could affect the decisions of jurors during a trial. Previous neuroimaging studies using faces of members of the general public have identified a pivotal role of the amygdala in perceiving threat. This functional magnetic resonance imaging study used face photographs of male prisoners who had been convicted of first-degree murder (MUR) as threatening facial stimuli. We compared the subjective ratings of MUR faces with those of control (CON) faces and examined how they were related to brain activation, particularly, the modulation of the functional connectivity between the amygdala and other brain regions. The MUR faces were perceived to be more threatening than the CON faces. The bilateral amygdala was shown to respond to both MUR and CON faces, but subtraction analysis revealed no significant difference between the two. Functional connectivity analysis indicated that the extent of connectivity between the left amygdala and the face-related regions (i.e. the superior temporal sulcus, inferior temporal gyrus and fusiform gyrus) was correlated with the subjective threat rating for the faces. We have demonstrated that the functional connectivity is modulated by vigilance for threatening facial features.  相似文献   
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BACKGROUND: The role of Helicobacter pylori infection in rheumatoid arthritis (RA) patients during treatment with non-steroidal anti-inflammatory drugs (NSAID) is still unclear. METHODS: By means of endoscopy and biopsy, gastroduodenal lesions and H. pylori status were repeatedly examined in 88 RA patients at intervals ranging from 26 to 49 months. Histology and culture were applied to determine H. pylori status. Serial changes in gastroduodenal lesions and histologic score for mucosal atrophy were compared among groups classified by initial and second H. pylori status. RESULTS: There were 28 patients with continuously positive H. pylori infection (CP group), 33 patients with continuously negative H. pylori infection (CN group), 7 patients in whom H. pylori status became negative (PN group), and 20 patients in whom H. pylori status could not be determined (UD group). Age, duration and species of NSAID, disease activity of RA, gastroprotective drugs applied and the prevalence of gastroduodenal mucosal lesions were not different among the groups at either the initial or the second examination. In the PN group, the score for mucosal atrophy at the second examination was significantly lower than at the initial examination, whereas no difference was found for the CP, CN and UD groups. Overall, histologic score for mucosal atrophy was higher in H. pylori-positive patients than in H. pylori-negative patients at both initial and second examination. CONCLUSIONS: In RA patients using NSAIDs, H. pylori infection may not affect the course of gastroduodenal lesions and activity of RA, but the infection contributes to mucosal atrophy.  相似文献   
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Blood levels of inflammatory-related cytokines, including interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α, are elevated in patients with alcoholic liver diseases. We investigated the effects of these cytokines and ethanol on the expression of hepatic asialoglycoprotein receptors (AGPRs) in a human hepatoblastoma cell line, HepG2. An [125I]-asialo-orosomucoid binding assay showed significant increases in surface AGPR numbers in HepG2 cells by treatment with IL-1β, IL-6, and TNF-α, to levels which were approximately 130% of the values in untreated control cells. However, the enhanced AGPR numbers induced by treatment with these cytokines were markedly suppressed, to 70%–80% of the number in the untreated cells, by treatment with ethanol. Immunological detection of AGPR with a specific antibody demonstrated that the modulation of surface AGPR numbers was correlated with the cellular expression levels of AGPR. These results suggest that, although IL-1β, IL-6, and TNF-α stimulate the synthesis of hepatic AGPR, ethanol suppresses the expression of AGPR augmented by these cytokines. This leads to an increase in serum asialo-orosomucoid levels caused by the disordered catabolism mediated by AGPR in patients with alcoholic liver disease. (Received Dec. 5, 1997; accepted May 22, 1998)  相似文献   
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Bronchoesophageal fistulae associated with lymphomas are generally associated with chemo-radiotherapy. We report here an unusual case of lymphoma with a therapy-unrelated bronchoesophageal fistula. Previously, only 10 similar cases have been reported. A 70-year-old male was diagnosed as having gastric diffuse large B-cell lymphoma in May 1998. In January 1999, he noted a cough after eating and drinking. Because of the presence of a febrile temperature, productive cough and dyspnea, he was referred to our hospital and diagnosed as having aspiration pneumonia. Antibiotics did not improve his symptoms. When tracheal intubation was performed with bronchoscopy, a bronchoesophageal fistula was revealed. Malignant lymphoma cells were found around the fistula in the biopsy specimen. The patient died of pneumonia after treatment with airway stenting and chemotherapy. Induction of necrosis by chemotherapy or low blood flow with stenting and dopamine probably caused enlargement of the fistula.  相似文献   
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