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Cyclosporin A (CsA) acts in two distinct modes against Schistosoma mansoni (S. mansoni) infection. It behaves in part as an antihelminthic and also as an immunomodulator. In this study, two methods were performed to increase the efficacy of the subcurative dose of CsA (30 mg/kg). These methods were, passive immunization where the drug was given simultaneously with rabbit antisera post infection and active immunization where the worm surface antigen was given prior to infection. The results showed that both methods led to enhancement of the curative effect of the CsA. However, the active immunization gave more significant reduction in liver worm and egg loads. Histopathological study showed small size and few number of hepatic granulomas in the passively immunized group while in the active group, there was just few and small collection of inflammatory cells. Moreover, the indirect fluorescent antibody test visualized damage to the worm tegument in both types of immunization. Thus, it could be concluded that active immunization increased the immunomodulatory effect of CsA in treatment of S. mansoni with less toxic effects by using a subcurative dose. 相似文献
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Microbiological analyses of workers' hands were made for the common indicators, including aerobic mesophilic plate counts (APC), as well as the common food pathogens. Opportunities were observed for cross-contamination of roast beef by workers' hands during slicing operations. Workers' hands showed APC counts of up to 10(7) CFU/hand and the presence of S. aureus and C. perfringens. Salmonella spp were not isolated from hands. These results show that handling of these foods by such workers would be a risk in transmitting pathogenic microorganisms to the foods and is apparent that it is necessary for these workers to take care of personal hygiene. Decimal reductions obtained in the microbiological counts after washing and antisepsis of workers' hands were at 2,6 logs cycles and still demonstrated the importance of this practice in food services by the fact that pathogens such as S. aureus and C. perfringens were inhibited or killed. 相似文献
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This case report details a single patient with pure red cell aplasia (PRCA) associated with clonal CD3+, TCRalphabeta+, TCR-Vbeta8+, CD8+, CD57+ large granular lymphocytosis whose anaemia did not respond to conventional immunosuppressive therapy but did respond to cyclosporin A (CsA). The patient has become dependent on CsA for 7 years in order to control anaemia due to associated PRCA. 相似文献
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The gastrolith of the crayfish Procambarus clarkii contains a small amount of an organic matrix that is mainly chitin and proteins, together with a large amount of calcium carbonate. As the first step to understand the mechanism of calcification, we tried to characterize matrix proteins in the gastrolith. An insoluble matrix protein, referred to as gastrolith matrix protein, was made soluble with 1% SDS containing 10 mM dithiothreitol, and was purified by reverse-phase high-performance liquid chromatography. The protein had a molecular weight of about 50,500 and a blocked amino terminus. By enzymatic digestion and microsequencing, five partial amino acid sequences with a total of 225 amino acid residues were identified and found to include a repetitive sequence not reported previously. 相似文献
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EH Wang SA Ebrahimi AY Wu C Kashefi E Passaro MP Sawicki 《Canadian Metallurgical Quarterly》1998,58(19):4417-4420
Pancreatic endocrine tumors occur both sporadically and as part of the multiple endocrine neoplasia type 1 (MEN1) syndrome. MEN1 is an autosomal dominant disease characterized by parathyroid hyperplasia, pancreatic endocrine tumors, and pituitary adenomas. The MEN1 gene called MENIN maps to chromosome 11q13 and is thought to function as a tumor suppressor gene. We previously demonstrated loss of heterozygosity (LOH) at 11q13 in approximately 40% of sporadic pancreatic endocrine tumors and hypothesize that MENIN is involved in the development of these tumors. Thirty-one sporadic pancreatic endocrine tumors were analyzed for mutation of MENIN by nonradioactive single-stranded conformation polymorphism. Twelve mutations were detected in 31 sporadic pancreatic endocrine tumors (34%). Twelve of these 31 tumors previously demonstrated loss of heterozygosity at 11q13. Of the tumors with LOH, seven contained mutations of the MENIN gene (58%). The majority of the MENIN mutations occurred within exon 2. Two independent mutations in MENIN were detected in a gastrinoma that also revealed LOH, leading to the possibility of another tumor suppressor gene locus at 11q13. Mutations were present in both benign and malignant pancreatic endocrine tumors, suggesting that a MENIN gene mutation is a frequent and early event in the tumorigenesis. The high incidence of truncating mutations in tumors with LOH at 11q13 support the hypothesis that MENIN is a tumor suppressor gene. 相似文献
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Whereas it is well-known that cocaine induces EEG desynchronization and behavioral excitation in animals and human subjects, the detailed effect of cocaine on EEG activity remains to be fully elucidated. This communication reports our attempts in quantifying the effect of cocaine on EEG signals recorded from the somatosensory cortex of adult male Sprague-Dawley rats under chloral hydrate anesthesia (400 mg/kg i.p.). Continuous, on-line and real-time power spectral analysis revealed that i.v. administration of two doses of cocaine (1.5 or 3.0 mg/kg) dose-dependently induced EEG desynchronization, as indicated by a decrease in the root mean square and an increase in the mean power frequency values. More interestingly, whereas both doses of cocaine promoted a reduction in the alpha (8-13 Hz), theta (4-8 Hz) and delta (1-4 Hz) spectral components, the beta band (13-32 Hz) underwent differential alterations. The lower dose of cocaine elicited a transient increase, followed by a decrease in the power of the beta band. A prolonged increase in the power of the beta band, on the other hand, was observed after the higher dose of cocaine. These results suggest that subtle changes in the individual EEG spectral components, which are dose-dependent, may underlie the EEG desynchronization induced by cocaine. 相似文献