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21.
Michael S. Exton Diane F. Bull Maurice G. King Alan J. Husband 《Pharmacology, biochemistry, and behavior》1995,50(4):675-679
The cascade of physiologic mechanisms in response to infection, the acute-phase response, is recognized as playing a major role in host defence. One such response is the hypoferremia that is consistently reported to occur during bacterial infection. This study aimed to determine whether the alterations in plasma iron were conditionable using the conditioned taste aversion (CTA) paradigm. The regime involved the pairing of a novel-tasting saccharin solution with bacterial endotoxin. Seven days after the initial pairing of these stimuli (the test day), the saccharin solution was represented. Animals exposed to this condition displayed a significant reduction in the level of plasma iron. Animals treated with an intraperitoneal dose of 400 μg/Kg lipopolysaccharide (LPS) displayed lower conditioned iron levels than rats infused with 100 μg/Kg LPS; however, this difference was not significant. These results showed that in addition to other acute-phase responses (fever and anorexia), plasma iron alterations are able to be manipulated through behavioral manipulations. 相似文献
22.
饮用水中过量铁和锰对蚕豆根尖细胞微核率的影响 总被引:4,自引:0,他引:4
目的 探讨饮用水中过量的铁和锰的致突变作用。方法 采用蚕豆根尖细胞微核技术。结果 当水中铁含量超过饮用水卫生标准3~10倍时,蚕豆根尖细胞微核率升高,且微核率与铁剂量间存在着明显的剂量-反应关系。锰对蚕豆根尖细胞微核率升高的作用不明显,只有在剂量高达卫生标准1000倍时,才会使蚕豆根尖细胞微核率有所增加。结论 过量的铁有致突变作用。 相似文献
23.
Prevention of nutritional deficiencies should be attained by the consumption of a good diet. Unfortunately, in the case of iron, this is not always possible, and it is advantageous to fortify food with iron. Milk-based formulas and cereals are the most commonly used iron-fortified products in infancy and early childhood. Bioavailability of iron from cereals is low and more clinical studies on the field are necessary to demonstrate the effectiveness of iron-fortified cereals in infants and children of developing countries. Infections and excessive blood loss in infancy related to the use of fresh, pasteurized or powdered cow milk result in much of the anemia we currently see in industrialized countries. Vitamin A deficiency interacts with iron metabolism and recent intervention studies have shown that anemia in Vitamin A deficient children can be successfully treated with oral supplements. 相似文献
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超顺磁氧化铁标记神经干细胞移植治疗帕金森病大鼠脑MRI改变的研究 总被引:3,自引:0,他引:3
目的研究应用超顺磁氧化铁(SPIO)标记神经干细胞(NSCs)移植治疗帕金森病(PD)大鼠脑部MRI的改变。方法从大鼠胚胎脑中分离培养中脑NSCs,用脂质体转染法将SPIO标记NSCs;同时制作大鼠PD模型,SPIO标记的NSCs移植到PD大鼠右侧纹状体区,分别在移植后1周、2周、4周、6周、8周和10周给大鼠行MRI检查,2周、4周、6周、8周、10周时进行旋转行为评分,并与NSCs组和对照组比较。结果脑内移植SPIO标记NSCs的PD大鼠1周后MRI检查显示在移植区呈低信号改变;移植后10周,在T2和T2梯度回波仍可观察到移植区的低信号,同时移植区有混杂信号。NSCs移植大鼠的旋转行为评分在移植后2-10周明显少于对照组(均P〈0.05)。结论SPIO标记的NSCs可以在MRI上显示其在移植大鼠脑部的分布和存活情况,有利于NSCs移植治疗PD后的疗效观察。 相似文献
26.
27.
Yamaji Yasuyoshi; Nakazato Yuichi; Oshima Naoki; Hayashi Matsuhiko; Saruta Takao 《Nephrology, dialysis, transplantation》2004,19(10):2592-2597
Background. Transferrin binds extracellular iron and protectstissues from iron-induced oxidative stress. The binding of ironand transferrin is pH dependent and conventional peritonealdialysis (PD) solutions have unphysiologically low pH values.Herein, we investigated whether conventional PD solution releasesiron from transferrin and if the released iron causes oxidativestress. Methods. Effects of PD solutions on iron binding to transferrinwere examined with purified human transferrin and transferrinin dialysates drained from PD patients. Oxidative stress inducedby iron released from transferrin was evaluated in terms ofthe formation of thiobarbituric acid reactive substance (TBARS)and protein carbonylation in the human red blood cell (RBC)membrane. The iron deposition in peritoneal tissue from PD patientswas evaluated by Perls' staining with diaminobenzidine intensification. Results. Low pH PD solution released iron from transferrin.This iron release occurred within 1 min. Iron release was notobserved in neutralized PD solution. Iron released from transferrinin low pH PD solution increased TBARS formation and proteincarbonylation in the human RBC membrane. Iron deposition, whichis prominent in the fibrotic area facing the peritoneal cavity,was observed in the peritoneum of PD patients. Conclusions. Iron released from transferrin in low pH PD solutioncan produce oxidative stress in the peritoneum of a PD patient.Neutralizing PD solution can avoid this problem. Iron depositionin the peritoneum may participate in the pathogenesis of peritonealfibrosis in PD patients. 相似文献
28.
Melanoses of the gastrointestinal tract 总被引:4,自引:0,他引:4
Electronmicroscopy and electron probe energy dispersive X-ray analysis studies have substantially contributed to our understanding of the various gastrointestinal tract melanoses. The nature of the pigment granules which occur in the various melanoses is discussed; their pattern of distribution in melanosis coli, melanosis ilei, melanosis duodeni and melanosis oesophagi is summarized and current knowledge of the aetiology and pathogenesis of these conditions is reviewed. Brief mention is also made of other examples of lipofuscin pigmentation, and a case of haemosiderosis ilei is described. 相似文献
29.
In vivo MRI of cancer cell fate at the single-cell level in a mouse model of breast cancer metastasis to the brain. 总被引:7,自引:0,他引:7
Chris Heyn John A Ronald Soha S Ramadan Jonatan A Snir Andrea M Barry Lisa T MacKenzie David J Mikulis Diane Palmieri Julie L Bronder Patricia S Steeg Toshiyuki Yoneda Ian C MacDonald Ann F Chambers Brian K Rutt Paula J Foster 《Magnetic resonance in medicine》2006,56(5):1001-1010
Metastasis (the spread of cancer from a primary tumor to secondary organs) is responsible for most cancer deaths. The ability to follow the fate of a population of tumor cells over time in an experimental animal would provide a powerful new way to monitor the metastatic process. Here we describe a magnetic resonance imaging (MRI) technique that permits the tracking of breast cancer cells in a mouse model of brain metastasis at the single-cell level. Cancer cells that were injected into the left ventricle of the mouse heart and then delivered to the brain were detectable on MR images. This allowed the visualization of the initial delivery and distribution of cells, as well as the growth of tumors from a subset of these cells within the whole intact brain volume. The ability to follow the metastatic process from the single-cell stage through metastatic growth, and to quantify and monitor the presence of solitary undivided cells will facilitate progress in understanding the mechanisms of brain metastasis and tumor dormancy, and the development of therapeutics to treat this disease. 相似文献
30.
乙二胺四乙酸铁钠强化酱油改善贫血效果观察 总被引:12,自引:0,他引:12
本研究比较了NaFeEDTA强化酱油、硫酸亚铁 (FeSO4)强化酱油对IDA改善效果。将 30 0名IDA学生分为对照组、NaFeEDTA强化酱油组Fe 5mg (人·日 )、FeSO4强化酱油组Fe5mg (人·日 ) ,比较新型铁强化剂 (NaFeEDTA)与传统铁剂 (FeSO4)对缺铁性贫血的改善作用。结果表明 ,对照组各项检验指标干预前后没有显著差异。其它各试验组呈现出较为一致的变化 ,表现为血红蛋白、血清铁、血清铁蛋白含量的显著性增加和原卟啉、总铁结合力、转铁蛋白的显著性下降。试验结果提示 ,乙二胺四乙酸铁钠与传统铁剂 (硫酸盐铁 )强化酱油均有改善学生贫血的作用 ,并且NaFeEDTA组的贫血改善率和Hb恢复水平优于FeSO4组。 相似文献