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OV Godukhin VI Arkhipov TG Shipakina SV Kalemenev EB Burlakova 《Canadian Metallurgical Quarterly》1995,35(4):500-506
The effects of daily intraperitoneal injections of alpha-tocopherol (30 mg/kg per day) and synthetic antioxidant IHFAN-30 (30 mg/day) in rats were compared during low-level ionizing radiation (10 days, dose rate 5 mGy/h, total dose 1.2 Gy). There were analysed: (1) amplitude of population spike of hippocampal slices; (2) endogenous phosphorylation in vitro of hippocampal synaptic proteins in the presence of cAMP; (3) formation, manifestation and reduction of food-procuring reflex. The findings showed that antioxidants made some correction of the functional state of hippocampal slices and cAMP-dependent phosphorylation system activity in brain cells from irradiated animals. No influence on training and memory functions was detected. 相似文献
915.
Excitation spectra and light curves were studied in three species of marine algae at monochromatic light excitation of the second-range afterglow. It was shown that light curves were satisfactorily described by an equation similar to the equation of enzyme catalysis with low light intensity of half-saturation (about 0.5 W X m-2). Shapes of the excitation spectra and spectral curves of quantum yield of the second-range afterglow was analysed considering the early non-linearity of its light curves. It was found that the results obtained and the literature data on a relatively high quantum yield of the second-range afterglow in the region of absorption of long-wave pigment system (above 680 nm) can be explained by the non-linearity mentioned above, not suggesting a participation of PSI in the generation of this afterglow. 相似文献
916.
Analysis of clinical and morphological findings in 306 patients making use of a complex of modern methods at tissue, cellular, and subcellular levels enabled the authors to define the early precancer changes in the bronchial epithelium. The diagnostic value of precancer changes in the lungs and lung cancer was assessed by successive statistical analysis and mathematical estimations. Medical mathematical decisive rules have been developed and are proposed for practical use, which permit the diagnosis of precancer and cancer of the lungs with a high degree of reliability (87 and 89%, respectively). 相似文献
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As there are no studies done on the prevalence of intestinal parasites in Lebanon since 1967, this study was undertaken to reveal the current patterns of intestinal parasitic infestations in Lebanese patients from two geographic regions: Beirut and Tripoli. Analysis was based on 33,253 stool specimens examined at the American University of Beirut Medical Center (AUH) and 11,611 specimens examined at the Islamic Hospital (IH) in Tripoli over five and three years, respectively. The prevalence of intestinal parasites at AUH and IH were 8.47% and 45.35%, respectively (overall 18%). The prevalence in males vs females was almost the same; being 8.23% vs 8.74%, and 44.67% vs 45.88%, at AUH and IH, respectively. Multiple infections were noted in 8.8% and 3.5% of stool specimens at AUH and IH, respectively. Although 18 different types of parasites were encountered, the most common pathogenic parasites found at AUH vs IH were: Giardia lamblia (20.7% vs 10.5% of parasites found), Entamoeba histolytica (19.41% vs 1.25%), Taenia spp. (6.03% vs 4.08%) and Ascaris lumbricoides (2.09% vs 46.97%). The overall yearly or monthly prevalence of parasites recovered from both hospitals did not show clear seasonal patterns. Compared to developed countries, Lebanon still suffers from a high prevalence and a wide spectrum of intestinal parasites. 相似文献
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