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Neurochemical Research - Most pharmacological studies concerning the beneficial effects of organoselenium compounds have focused on their ability to mimic glutathione peroxidase (GPx). However,...  相似文献   
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Pink-pigmented facultative methylotrophs (PPFMs) are one of the beneficial proteobacteria commonly found in phyllosphere, rhizosphere and as endophytes in cotton. To assess the impact of transgenic Bt-cotton on changes in the diversity and community profile of PPFMs by comparing with its non-transgenic cotton, a polyphasic approach including differential carbon-substrate utilization profiling and DNA fingerprinting techniques like ARDRA, RISA, BOX-PCR and ERIC-PCR were studied. PPFMs from phyllosphere, rhizoplane and internal tissues of the stem of both Bt-cotton and non-Bt-cotton were isolated and analysed in this study. All the results suggested that the diversity richness of PPFMs present in the phyllosphere, rhizoplane and internal tissues did not differ between Bt- and non-Bt-cotton. In this study, there was no evidence to indicate any adverse effects of Bt-cotton on the diversity of plant-associated methylobacteria.  相似文献   
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OBJECTIVE: To evaluate a new liquid-based cytology technique, Papspin (Thermo Shandon, Pittsburgh, Pennsylvania, U.S.A.). STUDY DESIGN: Three thousand cervical samples were examined. Each cervix was sampled with a Cervex Brush (Roche, Oss, the Netherlands), used first for a Pap smear and afterwards for a Papspin. One cytospin was prepared from each vial. RESULTS: An identical rate of epithelial cell abnormalities (3.8%) was detected with the two methods. Diagnostic concordance was observed in 86% of the 114 cases. Differences in diagnoses occurred in 168 of 3,000 cases (5.6%) concerning fungal infection (22 cases), epithelial cell abnormalities (24 cases) and minimal differences within the nonneoplastic Bethesda category (122 cases). Endocervical cells were absent from 158 Papspins (5.3%) and 66 Pap smears (2.2%), while they were present in the respective Pap smear or Papspin. Seven Papspins were considered "satisfactory, but limited by ..." (SBLB) as compared to 33 Pap smears given the absence of endocervical cells. CONCLUSION: Discordances concerning epithelial cell abnormalities were observed in 24 of 3,000 cases (0.8%). Fungal infections were more easily diagnosed on Papspin. The absence of endocervical cells in 5.3% of Papspins is due to a bias of methodology. Quality improvement was evident on Papspin for SBLB specimens. HPV testing could be performed with good results.  相似文献   
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Background  

The tolerability and efficacy of single dose albendazole (400 mg), diethylcarbamazine citrate (DEC) (6 mg/kg bodyweight) or co-administration of albendazole (400 mg) + DEC (6 mg/kg bodyweight) was studied in 54 asymptomatic Wuchereria bancrofti microfilaraemic volunteers in a double blind hospital-based clinical study.  相似文献   
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Ethylmalonic acid (EMA) accumulates in tissues and biological fluids of patients affected by short-chain acyl-CoA dehydrogenase deficiency (SCADD) and ethylmalonic encephalopathy, illnesses characterized by neurological and muscular symptoms. Considering that the mechanisms responsible for the brain and skeletal muscle damage in these diseases are poorly known, in the present work we investigated the effects of acute EMA administration on redox status parameters in cerebral cortex and skeletal muscle from 30-day-old rats. Animals received three subcutaneous injections of EMA (6 μmol/g; 90 min interval between injections) and were killed 1 h after the last administration. Control animals received saline in the same volumes. EMA administration significantly increased thiobarbituric acid-reactive substances levels in cerebral cortex and skeletal muscle, indicating increased lipid peroxidation. In addition, carbonyl content was increased in EMA-treated animal skeletal muscle when compared to the saline group. EMA administration also significantly increased 2’,7’-dihydrodichlorofluorescein oxidation and superoxide production (reactive species markers), and decreased glutathione peroxidase activity in cerebral cortex, while glutathione levels were decreased only in skeletal muscle. On the other hand, respiratory chain complex I-III activity was altered by acute EMA administration neither in cerebral cortex nor in skeletal muscle. The present results show that acute EMA administration elicits oxidative stress in rat brain and skeletal muscle, suggesting that oxidative damage may be involved in the pathophysiology of the brain and muscle symptoms found in patients affected by SCADD and ethylmalonic encephalopathy.  相似文献   
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Oxygen consumption and ammonia excretion rates were assessed for Terebratulina retusa (L.) held under 3 different regimes of temperature and food availability. These were: 5.6?C, no food (cold, starved); 5.8?C, food present (cold, fed) and 10.7?C food present (warm, fed), which simulated winter conditions, summer conditions and an intermediate treatment. Regressions of oxygen consumption on ash‐free dry weight (AFDW) had slopes which were not significantly different from each other and ranged from 0.953 to 0.999. A common slope of 0.976 was calculated and intercepts based on the common slope used to compare oxygen consumption in each treatment. The rise from cold, starved conditions to warm, fed was 24.5 per cent and this was significant (P < 0.05). Other differences were not significant (P > 0.05) but the cold, fed result was 12.6 per cent higher than cold, starved. Therefore feeding and temperature probably account for equivalent proportions of the rise in metabolism from winter to summer. Ammonia production data were much more variable. Excretion rates of a 50 mg AFDW individual (in ng‐at NH3‐N.h‐1) were as follows: cold, starved: 30.2 cold, fed: 7.1; and warm, fed: 22.9. Oxygen to nitrogen (O:N) ratios reflected these results. Mean O:N ratios were: cold, starved: 8.0; cold, fed: 42.4; warm, fed: 16.3. This shows that the simulated winter group relied heavily on protein to fuel their metabolism, the simulated summer group were less dependent on protein and the intermediate group probably used lipids and carbohydrates to fuel metabolic demands. This possibly reflected a trade off between food supply and increased metabolism from treatment to treatment, demonstrating a flexibility which could have been a contributing factor in the ecological tolerance and geological longevity of some brachiopods.  相似文献   
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Objectives: Endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) is a routine technique to assess solid pancreatic lesions. The aim of this study was to analyse the effect of optimizing laboratory procedures for specimen preparation on the rate and accuracy of the procedure. Methods: All EUS‐FNAs of solid pancreatic lesions performed during the year 2000 (Period 1) and from May 2003 to May 2004 (Period 2) were analysed. During Period 1, one experienced gastroenterologist performed all EUS‐FNAs, making direct smears and retrieving small fragments if present on the smear for histology. In Period 2, two endoscopists performed the EUS‐FNAs and all the material was emptied into a vial containing a fixative. Slide preparation was carried out in the pathology laboratory: one slide was processed using cytocentrifugation and cell blocks were made from left‐over material. Neither period utilized rapid on‐site evaluation. Results: During the two periods, 67 and 102 FNAs were analysed and showed significantly different (P < 0.001) non‐diagnostic rates of 22.8% and 4.2%, respectively. The increased diagnostic yield can be explained by the modified laboratory procedures and to a lesser extent by the increased experience of the gastroenterologists. Sensitivity, specificity, PPV, NPV and accuracy in the second time period were, respectively, 90.6%, 100%, 100%, 81.8% and 93.4%, not significantly different from the first time period. Conclusion: This study shows that accurate EUS‐FNA results may be obtained with a low non‐diagnostic rate comparable to those reported for rapid on‐site evaluation by optimizing laboratory specimen processing in a setting of solid pancreatic lesions.  相似文献   
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