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《中国现代医生》2020,58(34):60-63
目的 通过检测老年轻度认知障碍(MCI)患者血清瘦素(LEP)、甲状腺激素水平,分析其与局部脑血流量(rCBF)的关系。方法 选择本院收治的128 例老年MCI 患者,另选健康者128 例作为对照组。检测血清LEP、甲状腺激素、大脑各区域rCBF 水平并分析其相关性。结果 老年MCI 组患者左右侧额叶、右侧颞叶、左侧顶叶、左右侧基底节区域脑血流量[(43.81±8.62)mL/(100 g·min)、(43.24±7.93)mL/(100 g·min)、(45.14±6.98)mL/(100 g·min)、(45.86±6.77)mL/(100 g·min)、(67.95±8.52)mL/(100 g·min)、(68.36±8.34)mL/(100 g·min)]低于对照组[(46.39±8.31)mL/(100 g·min)、(46.52±8.56)mL/(100 g·min)、(47.37±7.04)mL/(100 g·min)、(48.25±6.98)mL/(100 g·min)、(70.34±8.96)mL/(100 g·min)、(70.58±8.57)mL/(100 g·min)](P<0.05)。老年MCI 组患者血清LEP、T3、FT3 水平[(4.87±1.56)μg/L、(1.21±0.16)nmol/L、(3.04±0.36)pmol/L]低于对照组[(11.45±3.92)μg/L、(1.68±0.21)nmol/L、(4.82±1.21)pmol/L](P<0.05),TSH 水平为(2.78±0.75)IU/mL,高于对照组的(1.13±0.38)IU/mL(P<0.05)。老年MCI 患者血清LEP 水平与左侧额叶、右侧颞叶、左侧顶叶rCBF 呈正相关(r=0.452、0.537、0.544,P 均<0.05),T3 水平与左侧额叶、右侧颞叶rCBF 呈正相关(r=0.427、0.521,P 均<0.05),FT3 水平与右侧颞叶rCBF 呈正相关(r=0.492,P<0.05),TSH 水平与左侧额叶、右侧颞叶rCBF 呈负相关(r=-0.463、-0.489,P 均<0.05)。结论 老年MCI 患者血清中LEP、T3、FT3 水平降低,TSH 水平升高,且与不同区域rCBF 有相关性,可通过调控脑血管功能影响rCBF 变化水平。 相似文献
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In this study, the effect of regular khat (Catha edulis Forsk) chewing (200 and 400 g) in humans on plasma leptin, nonesterified fatty acid, triacyglycerol, and total cholesterol levels was investigated. The results presented show that khat chewing increases plasma leptin concentration particularly in individuals who chew 400 g of khat leaves. The significance of increased plasma leptin is in explaining the underlying mechanism of the observed effects associated with khat chewing such as loss of appetite, decreased body weight, and hyperthermia. The decreased body weight was evident from the significantly lower body mass index of the khat leaves chewers group as compared to the non–khat leaves chewers group (control). Moreover, like leptin, the plasma levels of nonesterified fatty acids were significantly higher in those chewing 400 g of khat leaves. On the other hand, the plasma levels of triacylglycerol were significantly lower in the 2 khat-chewers groups (200 and 400 g of khat leaves), whereas plasma cholesterol levels were not affected by the 2 levels of khat leaves used in this study. The significance of these results may suggest that khat leaves may contain a component(s) that has the ability to reduce body weight via decreasing appetite. 相似文献
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瘦蛋白 (leptin)是由肥胖基因编码、脂肪细胞分泌的一种分子量为 16kDa的蛋白质 ,是一种重要的代谢调节信号 ,对人和动物的采食量、能量代谢、繁殖性能等具有重要调节功能 ,对人肥胖病的治疗和改善动物的生产性能、胴体组成等有良好的潜在应用前景 .主要概述了瘦蛋白基因的克隆、转录、表达调控以及瘦蛋白受体与信号转导等分子生物学特性 相似文献
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目的 探讨血清瘦素水平对老年男性骨质疏松的影响。方法 选取年龄在60-92岁的158例老年男性,采用双能X线法(DXA)检测骨密度,并根据测值将受试者分为骨质疏松组与非骨质疏松组,用放射免疫法(RIA)检测两组空腹血清瘦素浓度,进行比较研究。结果 血清瘦素测值在不同年龄组间的差异无统计学意义,而在肥胖组与非肥胖组间有显著差异(P〈0.01)。在老年男性骨质疏松组血清瘦素测值明显低于非骨质疏松组,两者具有显著差异(P〈0.05)。结论 血清瘦索测值并不随老年男性的年龄而变化。但与老年男性的体重指数呈正相关,血清瘦素对老年男性骨质疏松有较好的预示及保护作用。 相似文献
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Sánchez J Oliver P Picó C Palou A 《Pflügers Archiv : European journal of physiology》2004,448(5):500-506
We investigated diurnal changes in leptin and ghrelin levels in the stomach and in the systemic circulation and their relation to food intake rhythms in Wistar rats housed at 22 °C with a 12-h light/dark cycle and free access to food and water. Animals were sacrificed every 3 h over a 24-h period. Leptin and ghrelin levels in serum and in the gastric mucosa were analysed by immunoassay. Leptin mRNA levels were determined in the gastric mucosa by RT-PCR and in different adipose tissue depots (epididymal, retroperitoneal and mesenteric) by Northern blot. Ghrelin mRNA levels were determined by Northern blot. Gastric and serum leptin levels displayed similar diurnal rhythms, rising during the dark phase and decreasing gradually during the light phase. Leptin expression in the different adipose tissue depots correlated positively with circulating leptin levels (P<0.05), although there were some depot-associated differences. Leptin mRNA levels in the mesenteric depot correlated positively with food intake (P<0.05). In blood, ghrelin levels rose sharply just before the onset of the dark phase and dropped suddenly just after. In the stomach, ghrelin levels were high during the fasting period of light and low during the night, and correlated inversely with food intake, gastric contents and serum leptin levels (P<0.05). Leptin and ghrelin in the stomach and in the systemic circulation thus show diurnal variations that are influenced by food intake rhythms. The results agree with a role for ghrelin as a stimulant of meal initiation. 相似文献
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Obesity is a severely public health problem the whole society faces, and it is correlated closely with many diseases, such as diabetesⅡ, hypertension, coronary heart disease,gallqtone, and so on.Therefore it threatens people‘ s survival quality severely. Obesity is a multiple - factor disease including genetic, metabolic and behavioral factor, and the gene is the main determining factor. With the development of molecular biology technique, people have founded several genes involved in obesity. Among these genes, the research on obese gene is the most profound. The protein leptin is the expression product of the obese gene.This review elucidates the structure, the main biological function, the mechanism of leptin and it‘‘s relationship with obesity. 相似文献
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新生儿血清瘦素水平变化与胰岛素和生长激素关系的研究 总被引:2,自引:0,他引:2
目的 探讨新生儿血清瘦素来源及其与胰岛素和生长激素的关系。方法 采用放射免疫法检测 80例新生儿静脉血和脐血瘦素水平 ,根据不同胎龄新生儿出生体重值分为大于胎龄儿 (LGA)组 2 8例 ,适于胎龄儿 (AGA)组 36例 ,小于胎龄儿 (SGA)组 16例 ;采用Rohrer′s指数 =出生体重 (g)× 10 0 /身长 (cm) 3 估测新生儿营养状态。结果 早产儿血清瘦素水平明显低于足月儿 (0 6 6± 1 0 3ng/mlvs 3 5 9± 2 16ng/ml,P <0 0 1) ;AGA儿血清瘦素水平 (3 0 6± 0 96ng/m1)明显低于LGA儿(4 0 3± 2 2 2ng/m1) ,而高于SGA儿 (1 13± 1 98ng/m1) ;足月新生儿血清瘦素水平与Rohrer′s指数、新生儿体重、胎龄 ,血清胰岛素、生长激素水平呈显著正相关。结论 新生儿体内瘦素主要来源于自身脂肪组织 ,它反映新生儿的生长营养状态 ,推测瘦素可能通过胰岛素、生长激素共同调节新生儿的生长发育 ,在胎儿和新生儿生长发育中起重要作用。 相似文献