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Conjugated linoleic acid (CLA) is a unique lipid that elicits dramatic reductions in adiposity in several animal models when included at < or = 1% of the diet. Despite a flurry of investigations, the precise mechanisms by which conjugated linoleic acid elicits its dramatic effects in adipose tissue and liver are still largely unknown. In vivo and in vitro analyses of physiological modifications imparted by conjugated linoleic acid on protein and gene expression suggest that conjugated linoleic acid exerts its de-lipidating effects by modulating energy expenditure, apoptosis, fatty acid oxidation, lipolysis, stromal vascular cell differentiation and lipogenesis. The purpose of this review shall be to examine the recent advances and insights into conjugated linoleic acid's effects on obesity and lipid metabolism, specifically focused on changes in gene expression and physiology of liver and adipose tissue.  相似文献   
23.
目的 探讨性腺功能低减的青少年男性,短期雄激素替代治疗对血脂和超敏C反应蛋白(hsCRP)的影响。方法 本研究为前瞻性自身对照研究,共纳入33例性腺功能减退青少年男性。行短期(9个月)雄激素替代治疗,比较治疗前后血睾酮水平、第二性征发育程度、身高、握力、血红蛋白、血脂和hsCRP的差异。结果 (1)替代治疗后,睾酮水平明显升高,第二性征明显发育,身高、握力、血红蛋白显著增加(P值均〈0.05);(2)短期雄激素替代治疗后,总胆固醇(TC),低密度脂蛋白(LDL-c),高密度脂蛋白(HDL-c)和甘油三酯(TG)部有所下降,但无统计学差异(P〉0.5)。超敏CRP显著下降(P=0.025)。结论 (1)性腺功能低减的青少年男性,短期雄激素替代治疗,可以促进第二性征发育,增加身高、握力和血红蛋白;(2)短期雄激素替代治疗,对血脂无显著性影响。但是,可以使hsCRP明显下降。  相似文献   
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Recently, Korean people are consuming seaweeds almost 3.5 times more now than three decades ago. It is well known that seaweeds contain lots of soluble dietary fiber in addition to micronutrients such as β-carotene, iodine and some bioactive components. Seaweeds are considered to be effective for preventing chronic diseases including obesity, diabetes mellitus, atherosclerosis, cancer or constipation. This study was conducted to investigate the effect of seamustard intake on body weight gain, blood glucose level and lipid profiles in rats fed diets with different energy nutrient composition. Male Sprague-Dawley rats (average initial weight 103.7 g) were divided into groups for two experiments as follows; Control, M2.5 & M5 groups (Exp. I) and M5, M10, HCM5, HCM10, HFM5 & HFM10 groups (Exp. II). The rats were fed diet and water ad libitum for 4 weeks. In general, there was no significant difference in blood glucose and triglyceride concentration among groups. In Exp. I, serum LDL-cholesterol level of rats fed diet with 5% seamustard powder (M5) was significantly lower than that of control group, while HDL-cholesterol level, TC/LDL ratio and weight of adrenal gland were higher. In Exp. II, food intake, body weight gain and EER of high fat diet with 10% seamustard group (HFM10) were the lowest among groups. Except gastrocnemius muscle, all organ weights of HFM10 group were the lowest. Fecal cholesterol excretion and serum LDL-cholesterol concentration of HFM10 group were the highest, while serum HDL-cholesterol level was the lowest among groups. Interestingly, HDL-cholesterol concentration was the highest in HCM5 group among groups. From these results, it was suggested that seamustard intake might be more effective for body weight control, but not for improving blood lipid profiles in high fat diet than in high carbohydrate diet.  相似文献   
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Endoneurial hypoxia and a high frequency of closed capillaries have been found in chronic experimental diabetes and human diabetic sural nerve, respectively. These findings have led to the hypothesis that the pathogenesis of diabetic neuropathy is due to endoneurial hypoxia. To evaluate the role of endoneurial hypoxia in experimental diabetic neuropathy, the effects of supplementation and deprivation of oxygen on peripheral nerve lipid biosynthesis were studied in normal control and streptozotocin-induced diabetic rats. Defective lipid biosynthesis in diabetic nerve was partially prevented by oxygen supplementation. When normal rats were placed in a hypoxic chamber, lipid abnormalities similar to those observed in diabetic nerves were demonstrated in the absence of changes in nerve free sugars. These findings suggest that endoneurial hypoxia may underlie some key biochemical abnormalities encountered in experimental diabetic neuropathy.  相似文献   
27.
Injection of ozonized normal saline to animals with transplanted sarcoma-45 normalized energy metabolism in the liver, which is important for this organ's function under conditions of malignant growth. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 8, pp. 207–209, August, 1998  相似文献   
28.
A comparative study of the parameters of free-radical lipid peroxidation and antioxidant system was performed in children living in the North for various time periods. Intense lipid peroxidation was shown to be the key factor in the pathogeneses of several diseases caused by disturbances in the cellular membrane. Decreased resistance of red blood cells to peroxidative hemolysis is a phenomenon characterizing the adaptation-violating processes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 9, pp. 342–344, September, 1998  相似文献   
29.
本实验研究了连续服用茶多酚20天,对14月龄小鼠血及肝中SOD、GSH-Px和LPO的影响。结果表明茶多酚能提高血及肝中SOD及GSH-Px活性,与正常对照组比较P<0.01,同时能降低血及肝中LPO含量,与正常对照组比较P<0.01。提示茶多酚可通过降低机体自由基水平,起到抗衰老作用。  相似文献   
30.
本研究发现:家兔缺血60min(未再灌流)肾皮质和髓质内,脂质过氧化物含量均显著降低;缺血60min再灌流15min的肾皮质和髓质内,脂质过氧化物含量均显著增加。实验提示:缺血再灌流贤内氧自由基“爆发性”生成所引发的脂质过氧化可能是肾缺血性损伤的重要机制之一。  相似文献   
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