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31.
Zuzana Kubová Miroslav Kuba Jaroslav Hubacek František VíT 《Documenta ophthalmologica. Advances in ophthalmology》1990,75(1):67-72
In 80 subjects the dependence of movement-onset visual evoked potentials on some measures of stimulation was examined, and these responses were compared with pattern-reversal visual evoked potentials to verify the effectiveness of pattern movement application for visual evoked potential acquisition. Horizontally moving vertical gratings were generated on a television screen. The typical movement-onset reactions were characterized by one marked negative peak only, with a peak time between 140 and 200ms. In all subjects the sufficient stimulus duration for acquisition of movement-onset-related visual evoked potentials was 100ms; in some cases it was only 20ms. Higher velocity (5.6°/s) produced higher amplitudes of movement-onset visual evoked potentials than did the lower velocity (2.8°/s). In 80% of subjects, the more distinct reactions were found in the leads from lateral occipital areas (in 60% from the right hemisphere), with no correlation to handedness of subjects. Unlike pattern-reversal visual evoked potentials, the movement-onset responses tended to be larger to extramacular stimulation (annular target of 5°–9°) than to macular stimulation (circular target of 5° diameter).Abbreviation PREP
pattern-reversal visual evoked potentials 相似文献
32.
Phase II study of low-dose decitabine in patients with chronic myelogenous leukemia resistant to imatinib mesylate. 总被引:7,自引:0,他引:7
Jean-Pierre J Issa Vazganush Gharibyan Jorge Cortes Jaroslav Jelinek Gail Morris Srdan Verstovsek Moshe Talpaz Guillermo Garcia-Manero Hagop M Kantarjian 《Journal of clinical oncology》2005,23(17):3948-3956
PURPOSE: To determine the activity of decitabine, a DNA methylation inhibitor, in imatinib-refractory or intolerant chronic myelogenous leukemia. MATERIALS AND METHODS: Thirty-five patients were enrolled in this phase II study (12 in chronic phase, 17 in accelerated phase, and six in blastic phase). Decitabine was administered at 15 mg/m2 intravenously over 1 hour daily, 5 days a week for 2 weeks. DNA methylation was measured using a LINE1 bisulfite/pyrosequencing assay. RESULTS: Complete hematologic responses were seen in 12 patients (34%) and partial hematologic responses in seven patients (20%), for an overall hematologic response rate of 54% (83% in chronic phase, 41% in accelerated phase, and 34% in blastic phase). Major cytogenetic responses were observed in six patients (17%), and minor cytogenetic responses were seen in 10 patients (29%) for an overall cytogenetic response rate of 46%. Median response duration was 3.5 months (range, 2 to 13+ months). Myelosuppression was the major adverse effect, with neutropenic fever in 28 (23%) of 124 courses of therapy. LINE1 methylation decreased from 71.3% +/- 1.4% (mean +/- standard error of the mean) to 60.7% +/- 1.4% after 1 week, 50.9% +/- 2.4% after 2 weeks, and returned to 66.5% +/- 2.7% at recovery of counts (median, 46 days). LINE1 methylation at the end of week 1 did not correlate with subsequent responses. However, at day 12, the absolute decrease in methylation was 14.5% +/- 3.0% versus 26.8% +/- 2.7% in responders versus nonresponders (P = .007). CONCLUSION: Decitabine induces hypomethylation and has clinical activity in imatinib refractory chronic myelogenous leukemia. We hypothesize that the inverse correlation between hypomethylation 2 weeks after therapy and response is due to a cell death mechanism of response, whereby resistant cells can withstand more hypomethylation. 相似文献
33.
Sanguinarine and chelerythrine: assessment of safety on pigs in ninety days feeding experiment. 总被引:4,自引:0,他引:4
Pavel Kosina Daniela Walterová Jitka Ulrichová Václav Lichnovsky Marie Stiborová Helena Rydlová Jaroslav Vicar Vladimír Krecman Michael J Brabec Vilím Simánek 《Food and chemical toxicology》2004,42(1):85-91
Sanguinaria canadesis, Chelidonium majus and Macleya cordata have been used for centuries as alternative medicines. Currently the extracts from these medicinal plants are components of veterinary and human phytopreparations, and of oral-hygiene agents. Sanguinarine and chelerythrine (SA/CHE) are biologically active components of these extracts. They display distinct antibacterial and anti-inflammatory properties, but, on the other hand, they have been reported as having adverse effects - genotoxicity and hepatotoxicity. This paper is aimed at evaluation of the effects of daily administration of the extract from Macleya cordata (2 mg and 100 mg in 1 kg feed, sanguinarine:chelerythrine 3:1) in the diet on the health status of swine. After 90-day administration, alkaloids were retained to a different extent in tissues. The highest SA/CHE retention was detected in the gingiva (0.55 microg/g) and liver (0.15 microg/g), no SA/CHE were detected in muscles. Plasma SA levels attained 0.11 microg/ml. Treated animals did not display any results of hematological, biochemical or histological assay different from controls. A (32)P-postlabeling assay proved that no DNA-adducts with SA/CHE were detected in pig livers. We did not observe any symptom linked to epidemic dropsy syndrome often attributed to sanguinarine. In conclusion, an average daily oral dose of alkaloids up to 5 mg per 1 kg animal body weight proved to be safe. 相似文献
34.
35.
Jerzy Chojnacki Jan Kielar Waldemar Kuczyski Tom Najser Leon Kukieka Jaroslav Frantík Bogusawa Berner Vclav Peer Bernard Knutel Baej Gaze 《Materials》2022,15(21)
A comparative study was carried out of emissions from the catalytic combustion of pellets made from furniture board waste and pellets made from wood mixed with Fe2O3. The mass content of the Fe2O3 catalyst in the fuel was varied from 0% to 5%, 10%, and 15% in relation to the total dry mass weight of the pellets. The average flame temperature in the boiler was between 730 and 800 °C. The effect of the catalyst concentration in the fuel was analysed with respect to the contents of O2, CO2, CO, H2, and NOx in the flue gas and the combustion quality of the pellets in the heating boiler. Changes in the CO2 content and the proportion of unburned combustible components in the combustion residue were assessed. It was established that an increase in the Fe2O3 content of the prepared fuels had a positive effect on reducing NOx, CO, and H2 emissions. However, the proportion of iron oxide in the tested fuel pellets did not significantly influence changes in their combustion quality. A strong effect of the addition of Fe2O3 on the reduction of the average NOx content in the flue gas occurred with the combustion of furniture board fuel, from 51.4 ppm at 0% Fe2O3 to 7.7 ppm for an additive content of 15%. Based on the analysis of the residue in the boiler ash pan, the amount of unburned combustibles relative to their input amounts was found to be 0.09–0.22% for wood pellets and 0.50–0.31% for furniture board waste pellets. 相似文献
36.
Historical buildings and monuments are largely made of brickwork. These buildings form the historical and artistic character of cities, and how we look after them is a reflection of our society. When assessing ceramic products, great emphasis is placed on their mechanical properties, whilst their durability is often neglected. However, the durability or resistance to weathering of masonry elements is just as important as their mechanical properties. Therefore, this work deals with predicting the durability of solid-fired bricks before they are used when reconstructing monuments and historical buildings. Durability prediction is assessed by identifying defects in the material’s internal structure. These faults may not be visible on the element’s surface and are difficult to detect. For this purpose, non-destructive electroacoustic methods, such as the resonant pulse method or the ultrasonic pulse method, were used. Based on an analysis of the initial and residual mechanical properties after freezing cycles, four durability classes of solid-fired bricks were determined. This work aimed to find a way to predict the durability (lifetime) of an anonymous solid-fired brick, expressed in terms of the number of freeze cycles the brick would last, based on non-destructive measurements. 相似文献
37.
38.
Prospective study of signalling pathways in myeloma bone disease with regard to activity of the disease,extent of skeletal involvement and correlation to bone turnover markers 下载免费PDF全文
39.
Differential expression of homologous recombination DNA repair genes in the early and advanced stages of myelodysplastic syndrome 下载免费PDF全文
40.
Katerina Chudejova Veronika Rotova Anna Skalova Matej Medvecky Vaclava Adamkova Costas C. Papagiannitsis Jaroslav Hrabak 《Diagnostic microbiology and infectious disease》2018,90(2):148-150
ST252 Enterobacter cloacae, producing GES-5 carbapenemase, was isolated in a Czech hospital. blaGES-5 was part of a novel class 1 integron, In1406, which also included a new allele of the aadA15 gene cassette. In1406 was located on a ColE2-like plasmid, pEcl-35771cz (6953 bp). 相似文献