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41.
Summary. In order to investigate fat metabolism and the regulation of lipolysis and blood fuel metabolites by insulin, nine patients with chronic obstructive pulmonary disease (COPD) with chronic hypoxaemia and seven healthy control subjects of similar age were investigated by determination of the turnover rate of free fatty acids (TOR), using 1-14C-oleic acid as a tracer, and arterial concentrations of FFA, glycerol and 3-hydroxybutyrate. The measurements were performed in the basal state and during insulin and glucose infusion, aiming at euglycaemia at insulin levels of 50 and 100 mU l-1. The subjects' ages were 64±2.7 and 66±1.1 (mean±SEM) years in the COPD and control groups, respectively. TOR was 0.73±0.06 and 0.52±0.02 mmol min-1 (P<0.05) in the basal state, 0.33±0.04 and 0.30±0.02 at an insulin level of 50 mU I-1 and 0.32±0.08 and 0.24±0.02 at an insulin level of 100 mU I-1, in the COPD and control groups, respectively. Arterial FFA concentration was 0.98±0.08 and 0.75±0.06 mmol 1-1 (P<0.05) in the basal state in the COPD and control groups, respectively. During the clamp, the decrease in FFA mirrored that in TOR. The results show that the state of lipolysis is increased in severe COPD patients with chronic hypoxaemia. Furthermore, the results suggest a reduced effect of insulin in lipolysis.  相似文献   
42.
目的:观察糖心乐(TXL)对糖尿病性心肌病(DCMP)大鼠血糖、血脂的影响。方法:SD大鼠随机分为正常对照组、模型对照组、达美康组及糖心乐大、小剂量组。将除正常对照组外的各组大鼠腹腔注射STZ建立糖尿病模型,造模后8w分别给予生理盐水、达美康、TXL大小剂量灌胃,连续4w,正常对照组不做处理。结果:与模型对照组比较,达美康组、糖心乐大、小剂量组大鼠的血糖、甘油三酯(TG)、总胆固醇(TC)显著降低(P<0.05,P<0.01),高密度脂蛋白(HDL-C)显著升高(P<0.05,P<0.01)。TXL大剂量组的降低血糖、TC,升高HDL-C作用与达美康组相当,降低TG作用优于达美康组(P<0.05)。结论:TXL可通过降低血糖、TG、TC水平,升高HDL-C水平来改善DCMP大鼠心肌的功能。  相似文献   
43.
红景天苷对3T3-L1脂肪细胞糖代谢及细胞分化的影响   总被引:16,自引:0,他引:16  
目的:观察红景天苷对脂肪细胞糖代谢和细胞分化的影响,分析其改善糖代谢的可能机制.方法:检测红景天苷干预的脂肪细胞对 3H-葡萄糖的摄取,对红景天苷干预分化的细胞进行油红O染色后通过比色法分析脂肪细胞分化程度.逆转录多聚酶联反应(RT-PCR)检测脂肪细胞分化相关基因过氧化物体增殖剂活化受体-γ(PPAR-γ)、CAAT/增强子结合蛋白-α(C/EBP-α) mRNA的表达. 结果:红景天苷组葡萄糖摄取率为110.4%,明显高于正常对照组 (P<0.01);红景天苷明显抑制细胞分化及PPAR-γ、C/EBP-α mRNA表达,与对照组比较,P<0.01.结论:红景天苷促进3H-葡萄糖摄取,可抑制脂肪细胞分化,下调分化相关基因的表达.  相似文献   
44.
Many Australian Aboriginal bushfoods contain slowly digested carbohydrate which elicit low postprandial blood glucose and insulin responses compared to Western foods, such as wheat bread. This study has shown that incorporation of flour made from a slowly digested seed, Acacia coriacea , into wheat bread (18 g/82 g wheat flour) significantly reduces the initial rise in plasma glucose levels ( p < 0.05) and the area under the plasma glucose curve ( p < 0.005) in six healthy subjects. Insulin values were also lowered at 60 minutes ( p < 0.025) and 90 minutes ( p < 0.05). Our findings suggest that Acacia flour, when used to dilute wheat flour in the manufacture of breads, produces a very palatable food which could be useful in the diets of diabetic individuals.  相似文献   
45.
BACKGROUND: The aim of the present randomized study was to determine the effect of adding sufentanil to bupivacaine, compared with bupivacaine alone in caudal block, on the surgical stress response in children. METHODS: The children were premedicated with midazolam 0.5 mg/kg. All children received induction with nitrous oxide and sevoflurane. Anesthesia was maintained with the same volatile agents in the both groups. The children were randomly allocated to two groups. Group I received bupivacaine alone (n = 17) and group II received bupivacaine + sufentanil (n = 16). Caudal block was performed with 0.25% bupivacaine 2 mg/kg (group I) or 0.25% bupivacaine 2 mg/kg with sufentanil 0.5 microg/kg (group II) after induction of anesthesia. Blood samples were obtained after induction of anesthesia (T(0)) to measure baseline concentrations of cortisol, prolactin, glucose and insulin. Additional samples were obtained 30 min after the start of surgery (T(1)), and 60 min after the end of surgery (T(2)). RESULTS: All of the basal values (T(0)) were within the normal ranges of the authors' laboratory for children of this age group and there were no differences between the groups (P > 0.05). In both groups, glucose concentration increased at T(1), compared with T(0) and T(2) (P < 0.05). The glucose concentration was unchanged at T(2) compared with T(0) in both group (P > 0.05). In both groups, prolactin concentration increased at T(1), compared with T(0) and decreased at T(2), compared with T(1) (P < 0.05). Cortisol decreased at T(1) and T(2), compared with T(0) in both groups. (P < 0.05). Insulin concentration remained unchanged at T(0) and T(2), but increased slightly at T(1) in both groups (P > 0.05). There were no significant differences in plasma prolactin, cortisol, glucose and insulin levels between the two groups at T(1) and T(2) (P > 0.05). CONCLUSION: There is no advantage in adding 0.5 microg/kg sufentanil to bupivacaine over bupivacaine alone in the caudal block, with regard to the surgical stress response in children.  相似文献   
46.
Summary The effect of nifedipine 40 mg·day–1 for 3 months on glucose tolerance, insulin and C-peptide secretion after an oral glucose tolerance test (OGTT), intra-venous glucose tolerance test (IVGTT) and glucagon stimulatory test, has been studied in 8 moderately hypertensive women suffering from non-insulin dependent diabetes mellitus (NIDDM).No significant variation in glucose metabolism was noted after nifedipine treatment, except for a slight improvement in insulin secretion after OGTT at the end of the study. There was an increase in cholesterol as a collateral effect.  相似文献   
47.
The present study was undertaken to isolate a novel antidiabetic molecule from Swietenia macrophylla seeds. The hydroalcohol extract of Swietenia macrophylla seeds was subjected for bioassay guided isolation employing glucose utilization assay by the isolated rat hemi‐diaphragm method in vitro. One tetranortriterpenoid, swietenine, isolated from the chloroform fraction exhibited significant (p < 0.01) activity and the effect was comparable to that of human insulin (p < 0.01). Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
48.
目的观察高血压脑出血(ICH)患者血肿周围血-脑屏障葡萄糖转运蛋白1(GLUT1)表达的变化。方法采用免疫组化方法检测28例高血压ICH患者不同病程血肿周围脑组织GLUT1的表达情况。结果与对照组相比,ICH组发病12 h GLUT1表达开始增强,24 h、48 h表达最强(均P<0.01);72 h表达明显下降(P<0.01)。结论ICH早期血肿周围GLUT1表达增多,有助于恢复脑的能量代谢。  相似文献   
49.
50.
目的 探讨胰岛素抵抗 (IR)在糖耐量减低 (IGT)大血管并发症中的作用。方法 测定 1 2 0名IGT患者和 96名糖耐量正常(NGT)对照者的空腹血糖 (FBG)、胆固醇 (TC)、甘油三酯 (TG)、胰岛素 (FINS)及餐后 2h血糖 (PBG) ,并测量身高、体重、腰围、臀围 ,计算相对胰岛素敏感指数 (RISI)、体重指数 (BMI)、腰臀比 (WHR) ,结合其颈动脉多普勒超声检测结果进行对比分析。结果 IGT组及NGT组颈动脉粥样斑块发生率有显著性差异 (P <0 .0 0 1 ) ,斑块面积与RISI呈负相关 (r =- 0 .45 ,P <0 .0 1 ) ,与餐后 2h血糖 (r =0 .39,P <0 .0 1 )、BMI(r=0 .48,P <0 .0 1 )及WHR(r=0 .41 ,P <0 .0 1 )正相关 ,而与TG、FBG、TC、FINS无相关性 (P >0 .0 5)。IGT组患者有斑块和无斑块者之间RISI、WHR、BMI、餐后 2h血糖、TG之间也存在显著性差异 (P <0 .0 1 )。结论 胰岛素抵抗与颈动脉粥样硬化的发生密切相关 ,是IGT患者发生大血管并发症的重要原因。  相似文献   
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