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701.
Zdenka Gasparova Pavol Janega Nada Pronayova Tibor Liptaj 《Central European Journal of Biology》2012,7(5):810-816
Background
Studies of the middle-aged hippocampus may clarify the early mechanisms of aging and may lead to timely initiation of treatment for age-related cognitive impairments. 相似文献702.
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704.
Nabila E. Abdelmeguid Mahmoud I. Khalil Nada S. Badr Afrah F. Alkhuriji Mohamed S.A. El-Gerbed Ahmed S. Sultan 《Saudi Journal of Biological Sciences》2021,28(4):2254-2266
Colostrum, the sole diet for newborns, is an emerging nutraceutical. To date, the chemopreventive effect of Bovine Colostrum against liver injury induced by the potent carcinogen, 7,12-dimethyl-Benz[a]anthracene (DMBA) is unexplored. Humans are daily exposed to DMBA which is a highly lipophilic environmental organic pollutant. The study aimed to investigate the hepatoprotective role of Bovine Colostrum against DMBA-induced hepatotoxicity using a rat model. Fifty male rats were divided into five groups; GI (control), GII (olive oil, vehicle for DMBA), GIII (DMBA), GIV (DMBA + Bovine Colostrum), GV (Bovine Colostrum). After 12 weeks, body weight changes and mortality were calculated. Histological and ultrastructural examinations of liver tissue were performed. Expressions of p53, TGFβ2, TNF-α, S6K2, and c20orf20 were assessed by RT-PCR. Post-treatment with Bovine Colostrum increased both the body weight and the survival rate of rats treated with DMBA. In addition, remarkable protection against the pathological effect of DMBA was noted. Ultrastructurally, Bovine Colostrum ameliorated/prevented most of the toxic effects of DMBA on hepatocytes, including irregularities of nuclear envelope, clumping, and margination of heterochromatin aggregates, segregated nucleoli, and mitochondrial pleomorphism. Bovine Colostrum administration down-regulated p53, C20orf20, and S6K2 mRNA levels, and up-regulated TNF-α and TGFβ2. In conclusion, Bovine Colostrum have a protective effect against DMBA-induced toxicity on the liver of albino rats. Consequently, Bovine Colostrum may prevent polycyclic aromatic hydrocarbons-induced hepatotoxicity and may be useful in promoting human health if supplemented in the diet. 相似文献
705.
Ahmed M. Salem Assoc. Prof. Dr. Nada M. Mostafa Prof. Dr. Eman Al-Sayed Dr. Iten M. Fawzy Prof. Dr. Abdel Nasser B. Singab 《化学与生物多样性》2023,20(7):e202300200
Alzheimer's disease (AD) is a major health problem. Cholinergic transmission is greatly affected in AD. Phytochemical investigation of the alkaloid rich fraction (AF) of Erythrina corallodendron L leaves resulted in isolation of five known alkaloids: erysodine, erythrinine, 8-oxoerythrinine, erysovine N-oxide and erythrinine N-oxide. In this study, eysovine N-oxide was reported for the second time in nature. AF was assayed for cholinesterase inhibition at the concentration of 100 μg mL−1. AF showed a higher percent inhibition for butyrylcholinesterase enzyme (BuChE) (83.28 %) compared to acetylcholinesterase enzyme (AChE) (64.64 %). The isolated alkaloids were also assayed for their anti-BuChE effect. In-silico docking study was done for the isolated compounds at the binding sites of AChE and BuChE to determine their binding pattern and interactions, also molecular dynamics were estimated for the compound displaying the best fit for AChE and BuChE. In addition, ADME parameters and toxicity were predicted for the isolated alkaloids compared to donepezil. 相似文献
706.
Nada Pipan 《Cell and tissue research》1966,73(4):534-539
Zusammenfassung 13, 15 und 17 Tage alte Mäuseembryonen wurden zwei oder drei Tage vor der Untersuchung mit 1200, 1500, 1700 bzw. 1800 r in utero bestrahlt. In den Leberzellen 13 und 15 Tage alter Embryonen fanden wir mehr oder weniger stark geschwollene Mitochondrien, deren Oberfläche durch einzelne oder mehrere Invaginationen vergrößert ist. In das Mitochondrium hineinragendes Cytoplasma wird manchmal ganz eingeschlossen und enthält oft konzentrische Membrangebilde. Diese Befunde werden im Zusammenhang mit den von anderen Autoren bobachteten pathologischen Veränderungen der Lebermitochondrien diskutiert.
Summary 13, 15, and 17 days old mouse embryos were irradiated with 1200, 1500, 1700, or 1800 r. Their livers were examined two or three days after the irradiation. The liver cells of the 13 and 15 days old embryos showed more or less swollen mitochondria, the surface of which was often increased by one or more invaginations. The surrounding cytoplasm protruded into the mitochondria and was occasionally completely enclosed. Often these cytoplasmic protrusions contained concentric membraneous structures. These findings are discussed taking into consideration the pathologic changes in liver mitochondria described by other authors.相似文献
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Nada Ćosić Štěpánka Říčanová Josef Bryja Aleksandra Penezić Duško Ćirović 《Conservation Genetics》2013,14(2):345-354
The European ground squirrel (EGS) (Spermophilus citellus) populations of Vojvodina (Serbia) represent the southernmost part of its distribution in the Pannonian lowland. For species with low dispersal abilities a presence of even weak barriers can have significant influence on genetic structure among adjacent populations. We examined here the effects of habitat fragmentation and river barriers on the genetic structure of the EGS based on 12 microsatellite loci. Bayesian clustering methods were used as additions to classical population genetic approaches. We found that EGS populations in Vojvodina are highly fragmented, but their genetic variation is still higher than in peripheral populations in Central Europe. Populations in Vojvodina consistently grouped into three genetic clusters. The Danube, but not the Tisza River, represents an important barrier to gene flow. EGS populations in the studied area did not show the signs of recent genetic bottlenecks, as would be expected from observations of recent population declines. Conservation strategy should be focused on maintenance of remained suitable habitats and optimal population sizes. 相似文献
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As the minority group frequently at the centre of public fear in the post-9/11 era, Arab Americans’ own sentiment toward, and concerns with, crime, has eluded scholarly attention. This study investigated their fear of crime net of five empirically validated fear of crime theoretical models. Face-to-face interviews with a random sample of Arab and non-Arab households in Metro-Detroit, Michigan indicated that net of all controls, Arab Americans experienced significantly higher levels of fear concerning both general and bias crimes than non-Arab Americans. The greater fear among Arab Americans calls for policy and practice change, and moving from perceiving Arab Americans as a major “source” of fear, to “carriers” of fear who are in need of more attention, care, and assistance. 相似文献