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NB Ampilova IIa Bereznaia KV Grachev EIa Gurevich EV Strakhovich 《Canadian Metallurgical Quarterly》1996,92(6):20-23
An algorithm and a personal computer program for automatic distinguishing between EEC records containing evoked and no potentials, based on the detected invariants reflecting experts' experience in evoked potential analysis have been developed. The efficiency of the programme (its high accuracy and speed, low volume) has been demonstrated in the system for automatic determination of the hearing level by long-latent evoked potentials. It is easily modifiable to identify evoked potentials from other modalities (visual, somatosensory ones) in the systems using the traditional and/or up-to-date computerized EEC equipment. 相似文献
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Cytogenetic study conducted after a single intraperitoneal injection of cyclophosphane in doses of 10, 20, and 40 mg/kg showed in 1.5-2-month-old male mice that the level of bone marrow cells damaged by the mutagen was significantly higher in NZW animals than in C57Bl/6 animals. The ability to produce active oxygen forms in response to addition of opsonized zymosan and phorbol myristate acetate was also higher in bone marrow suspensions of NZW mice. The higher sensitivity of NZW animals to pro-oxidant and clastogenic effects may be related to the genetically determined decrease of antioxidant protection in NZW animals. 相似文献
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The known literature data concerning the mechanisms of molecular action of vitamin E in biological membrane systems are reviewed. The role of vitamin E, possessing a broad range of biological activities, as a universal stabilizer of biological membranes in normal oxygen metabolism and peroxidation, and also in disorders of normal metabolism resulting in pathological alterations, has been discussed. The participation of vitamin E in redox reactions taking place in lipid media, its interaction with singlet oxygen, free fatty acids and enzyme systems are considered. Physiological effects of vitamin E and its ability to prevent numerous pathologies are also considered. Vitamin E was concluded to be a universal participant of antioxidant defence reactions in biological membranes, since it acts at all stages of membrane oxidative damage. 相似文献
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AV Sidorov VV Zverev AG Zdanovski? AV Pugach VV Maliushova OG Andzhaparidze 《Canadian Metallurgical Quarterly》1994,39(1):6-10
Lack of uniformity in the classification of oral diseases, and variability of study designs, measurements, methods, and statistical formats, hamper the interpretation, comparison and review of the evidence linking smoking and oral diseases. However, there have been a significant number of controlled studies, allowing definitive conclusions to be drawn. This review of 22 controlled scientific studies from 1983-1992, considers the role of smoking as an aetiological agent in: gingival problems (impaired gingival bleeding, ANUG), periodontal problems (periodontitis, bone loss, tooth loss), and caries. 相似文献