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排序方式: 共有212条查询结果,搜索用时 406 毫秒
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Kesik V Lenk MK Kurekci AE Acikel CH Akgul EO Aydin A Erdem O Gamsizkan M 《Biological trace element research》2008,123(1-3):168-178
Aspirin is widely used as an antiinflammatory drug especially in children with rheumatic fever arthritis. The diminishing effects of aspirin on antioxidant enzymes and hepato-renal systems at high doses are well-known. It is now evident that the damage at antioxidant system worsens the clinical picture of the disease and prolongs the treatment time. Thus, we investigated the effect of antioxidant enzyme cofactors-zinc and selenium-supplementation on superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) levels (erythrocyte and liver) and hepato-renal toxicity during aspirin treatment at therapeutic doses. The rats were divided into five groups. The first and second groups were given aspirin 75 mg/kg/day and aspirin plus selenium (Selenium 200, selenium 200 mg tablet as selenium yeast, GNC) and zinc (Zinc 100, zinc 100 mg tablet as zinc gluconate, GNC), respectively, the third and fourth take 50 mg/kg/day aspirin and aspirin plus selenium and zinc twice a day, respectively. The fifth group was control. The rats were treated with aspirin for 5 weeks as in the treatment of rheumatic fever arthritis in children. Erythrocyte SOD and MDA levels were preserved with supplementation, whereas there was no change for GSH-Px levels. Liver SOD, GSH-Px, and MDA levels were not changed. In zinc- and selenium-supplemented groups, the levels of serum alanine aminotransferase, uric acid, and direct bilirubin levels were found statistically decreased compared with nonsupplemented groups. There was no significant histopathologic change in specimens of hepatic and renal tissues. Trace element supplementation may prevent free radical damage and shorten treatment time in children using long-term aspirin treatment. 相似文献
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Ziver T Yuksel P Ipek G Yekeler I Bayramoglu Z Tireli E Saribas S Aslan M Yalvac SD Ozdomanic I Torlak Z Dirican A Torun MM Kocazeybek B 《The new microbiologica》2010,33(3):233-242
Helicobacter pylori is thought to be related to atherosclerosis and aneurysm development. We aimed to detect virulance factors of H. pylori and examine the potential etiopathogenetic relationship between aortic aneurysm and H. pylori, 58 abdominal aortic aneurysm (AAA) and 38 ascending aortic aneurysm (AsAA) cases and 57 Healty control group (HCG) were included. We investigated H. pylori IgG by ELISA and virulance factors by Western-Blot (WB) method. No difference was found between AAA (67.24%), AsAA (73.68%) and HCG (57.89%) for H. pylori IgG (p > 0.05). A significant difference was found between AsAA (78.95%) and HCG (57.89%) for H.pylori IgG (p < 0.05) by ELISA and a significant difference was found only between AsAA (100%) and HCG (37.5%) for H. pylori IgG in the 45-55 age group by WB. A statistically significant difference was found between AAA and AsAA for VacA and CagA + VacA and CagA + VacA + UreA antigens and also a significant difference was found between AsAA and HCG for CagA + UreA antigens (p < 0.05). Finally, we suggest that H. pylori VacA has a more important role than CagA in the development of two aneurysms especially in ruptured AAA. New extended studies detecting H. pylori DNA are needed to detect the aetiopathogenesis between aneurysm types and H. pylori. 相似文献
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Sacrificial bonds and hidden length: unraveling molecular mesostructures in tough materials
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Fantner GE Oroudjev E Schitter G Golde LS Thurner P Finch MM Turner P Gutsmann T Morse DE Hansma H Hansma PK 《Biophysical journal》2006,90(4):1411-1418
Sacrificial bonds and hidden length in structural molecules and composites have been found to greatly increase the fracture toughness of biomaterials by providing a reversible, molecular-scale energy-dissipation mechanism. This mechanism relies on the energy, of order 100 eV, needed to reduce entropy and increase enthalpy as molecular segments are stretched after being released by the breaking of weak bonds, called sacrificial bonds. This energy is relatively large compared to the energy needed to break the polymer backbone, of order a few eV. In many biological cases, the breaking of sacrificial bonds has been found to be reversible, thereby additionally providing a "self-healing" property to the material. Due to the nanoscopic nature of this mechanism, single molecule force spectroscopy using an atomic force microscope has been a useful tool to investigate this mechanism. Especially when investigating natural molecular constructs, force versus distance curves quickly become very complicated. In this work we propose various types of sacrificial bonds, their combination, and how they appear in single molecule force spectroscopy measurements. We find that by close analysis of the force spectroscopy curves, additional information can be obtained about the molecules and their bonds to the native constructs. 相似文献
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The influence of Helicobacter pylori infection on the prevalence of endoscopic erosive esophagitis 总被引:2,自引:0,他引:2
OBJECTIVES: This study aimed to determine the frequency of endoscopic esophagitis and Helicobacter pylori infection in a large Turkish population over a 6-year period. METHODS: We studied a consecutive series of 14,380 patients who had been newly referred for diagnostic esophagogastroduodenoscopy from 2000 to 2006. The mean age value was 45 +/- 10 (18-89) years. All endoscopic findings were retrospectively evaluated. Two antral and two corpus biopsies were taken from patients for rapid urease test. Endoscopic esophagitis was defined as the presence of erosions and/or ulceration. The relationship between erosive esophagitis and various relevant factors was analyzed. RESULTS: The overall prevalence of endoscopic esophagitis was 7.8% (95% CI, 6.9-8.1). The prevalence of positive rapid urease test was 49% (95% CI, 38-53) in patients with esophagitis and 85% (95% CI, 70-96) in patients without esophagitis (p < .001). From 2000 to 2006, the frequency of endoscopic esophagitis and the rate of positive rapid urease test remained unchanged. After adjusting for the effects of mean age, male gender, and percentage of hiatal hernia, there was a 0.785% risk reduction in esophagitis with every 1% increase in the rate of positive rapid urease test result. CONCLUSIONS: The frequency of endoscopic esophagitis is significantly lower in patients with a positive rapid urease test result. This negative correlation with H. pylori infection reflects a protective effect of H. pylori from endoscopic esophagitis in a Turkish population and deserves further investigation. 相似文献
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Cytokine signaling plays an important role in the survival and differentiation of vertebrate hematopoietic cells. In red blood cells, erythropoietin is a key component of the differentiation program and maintains the homeostasis of the erythroid compartment. In the adult, anemia stimulates high levels of circulating erythropoietin that drives erythropoiesis to restore normal levels of red blood cells in circulation. Erythropoietin activates the erythropoietin receptor on immature red blood cell precursors to promote their survival and differentiation. Although extensively studied in mammalian systems, a complete understanding of the function of the erythropoietin receptor during primitive erythropoiesis has been lacking. To address this problem, we have cloned the Xenopus laevis erythropoietin receptor in order to further understand the development of primitive erythropoiesis. The amphibian erythropoietin receptor shares 33% amino acid sequence identity with the mammalian erythropoietin receptors and contains the conserved extracellular ligand binding and fibronectin domains, the WSXWS motif common to cytokine receptors, and several tyrosine phosphorylation sites located on the intracellular domain of the receptor. Expression of the erythropoietin receptor is first detected by in situ hybridization in the ventral blood island during tailbud stages. 相似文献
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Muhammad Abu Bakar Zia Ufuk Demirel Muhammad Azhar Nadeem Mehmet Emin aliskan 《Physiology and Molecular Biology of Plants》2020,26(5):1003-1020
Potato is one of the most important food crops all over the world. Breeding activities for this crop are mainly aimed to improve the quality and yield of tuber. However, genetic architecture of various traits contributing to the quality and yield of potato are not yet completely understood. Genome wide association studies provides a broader way to identify the genomic regions associated with various traits. Panels of 237 tetraploid potato genotypes from different countries were grown for two consecutive years 2016 and 2017 at experimental research area of Potato research center Niğde, Turkey. A genome wide association study using SolCAP 12K array was performed for various morpho-agronomic traits. Structure algorithm and neighborhood joining analysis clearly divided all genotypes into 4 clusters on the basis of their origin. For the marker trait association, Mixed Linear Model in TASSEL was performed and 36 genomic regions were found for the traits under study. The mean r2 value was found to be 0.92 and mean significant LD was 47.5% in the populations. LD patterns reflected the breeding history of potato. The findings of present study provide a framework which could be useful for future potato breeding programs to enhance the production and to reduce the challenges in the coming years to feed world’s population. 相似文献