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61.
程海东 《复旦学报(医学版)》2002,29(4):294-295,299
目的 研究妊娠期糖尿病与胎儿生长发育中糖代谢特点的关系。方法 选择妊娠期糖尿病25例(GDM组),正常孕妇20例(对照组),分别测孕妇空腹血糖、糖耐量、C肽、IGF-I、新生儿出生2h内空腹血糖,并依据新生儿出生体重分为大于胎龄儿组(LGA组,≥4000g),适于胎龄儿组(AGA组,2500-3999g)。结果 C肽及新生儿出生2h内空腹血糖GDM组与对照组差异有显著性;糖耐量各时点血糖值餐后2h血糖值LGA和AGA组差异有显著性。结论 血糖始终是影响胎儿生长发育的重要因素,孕妇餐后2h血糖水平与巨大儿的发生呈正相关。 相似文献
62.
Summary To define the glucose to insulin dose-response relationship before the onset of diabetes, we studied 22 nondiabetic co-twins of patients with Type 1 (insulin-dependent) diabetes mellitus and nine control subjects. All had intravenous glucose tests at 0.02, 0.1 and 0.5 g/kg and were followedup prospectively for at least 6 years. Seven twins developed diabetes a mean of 7 months later; the remaining 15 are now unlikely to develop diabetes. The seven pre-diabetic twins had higher fasting insulin levels than control subjects (4.2±2.0 vs 1.8±1.8 nmol/l; p<0.05); but lower glucose clearance (1.0±0.5 vs 1.9±0.7 %/min; p<0.05), first phase insulin response at 0.5 g/kg (21.1±23.2 vs 143±50 nmol/l; p<0.0001), and total insulin responses at 0.1 g/kg (p<0.05) and 0.5 g/kg (p<0.00005). Using a curve-fitting programme, the normal glucose to insulin relationship was lost in prediabetic twins who had lower coefficient of determination (R2) than control subjects (p<0.01). In contrast, 15 low-risk twins and their nine control subjects had similar fasting glucose and insulin levels, glucose clearance, R2 and insulin secretory responses to different glucose loads. The positive predictive values of subnormal R2 and subnormal first phase insulin response were 67 % and 58 % respectively. These observations demonstrate an altered glucose to insulin dose-response relationship and loss of maximum insulin secretory response to glucose before the onset of Type 1 diabetes. 相似文献
63.
目的:探讨儿童甲亢患者糖代谢紊乱的特点。方法:用SUPER GLUCOCARD^TM血糖仪和放射免疫方法检测29例甲亢患儿餐前、餐后60min、120min血糖和餐前、餐后60min胰岛素、C肽、胰高糖素、皮质醇及T3、T4、TSH、TGA、TMA(其中10例糖耐量减低为甲亢1组,另19例糖耐量正常为甲亢2组),并与20例健康儿童进行比较。结果:(1)34.5%甲亢患儿出现糖代谢紊乱,病程大于1年和小于1年糖代谢紊乱发生率为50%,9%(P<0.05)。(2)甲亢1组餐后60min胰岛素、胰岛素/血糖、胰岛素/胰高糖素显著升高(P<0.05)。结论:甲亢儿童存在糖代谢紊乱现象,表现为葡萄糖耐量减低和胰岛素拮抗,其发生与病程有关,病程较长,发生率较高。糖代谢紊乱可能与自身免疫、胰岛β细胞功能受损及胰岛素拮抗有关。 相似文献
64.
Nitric oxide is not involved in the initiation of insulin secretion from rat islets of Langerhans 总被引:1,自引:1,他引:0
P. M. Jones S. J. Persaud T. Bjaaland J. D. Pearson S. L. Howell 《Diabetologia》1992,35(11):1020-1027
Summary The involvement of nitric oxide as an intracellular messenger in the control of insulin secretion from pancreatic Beta cells was studied in rat islets of Langerhans by measuring: (i) nitric oxide generation in response to physiological insulin secretagogues; (ii) the effects of inhibitors of nitric oxide synthesis on insulin secretory responses to physiological secretagogues, and on insulin synthesis; (iii) changes in islet cyclic guanosine monophosphate in response to secretagogues; (iv) the effects of exogenous cyclic guanosine monophosphate and dibutyryl cyclic guanosine monophosphate on insulin secretion from electrically permeabilised islets and from intact islets, respectively. These studies produced no evidence that nitric oxide generation is required for the initiation of insulin secretion by common secretagogues. However, the results of our experiments suggest that the generation of nitric oxide may be involved in long-term, glucose-dependent increases in cyclic guanosine monophosphate content of islet cells, although the physiological relevance of these changes requires further investigation. 相似文献
65.
Summary Insulin resistance and a defective insulin activation of the enzyme glycogen synthase in skeletal muscle during euglycaemia may have important pathophysiological implications in Type 2 (non-insulin-dependent) diabetes mellitus. Hyperglycaemia may serve to compensate for these defects in Type 2 diabetes by increasing glucose disposal through a mass action effect. In the present study, rates of whole-body glucose oxidation and glucose storage were measured during fasting hyperglycaemia and isoglycaemic insulin infusion (40 mU·m–2min–1, 3 h) in 12 patients with Type 2 diabetes. Eleven control subjects were studied during euglycaemia. Biopsies were taken from the vastus lateralis muscle. Fasting and insulin-stimulated glucose oxidation, glucose storage and muscle glycogen synthase activation were all fully compensated (normalized) during hyperglycaemia in the diabetic patients. The insulin-stimulated increase in muscle glycogen content was the same in the diabetic patients and in the control subjects. Besides hyperglycaemia, the diabetic patients had elevated muscle free glucose and glucose 6-phosphate concentrations. A positive correlation was demonstrated between intracellular free glucose concentration and muscle glycogen synthase fractional velocity insulin activation (0.1 mmol/l glucose 6-phosphate: r=0.65, p<0.02 and 0.0 mmol/l glucose 6-phosphate: r= 0.91, p<0.0001). In conclusion, this study indicates an important role for hyperglycaemia and elevated muscle free glucose and glucose 6-phosphate concentrations in compensating (normalizing) intracellular glucose metabolism and skeletal muscle glycogen synthase activation in Type 2 diabetes. 相似文献
66.
Summary Insulin binding to trophoblast plasma membranes and the placental glycogen content were measured in twelve healthy women, in eleven well-controlled gestational diabetic women who were treated either with diet alone (n=4) or with insulin (n=7) and in 18 women with well-controlled overt diabetes mellitus (six White B; four White C; eight White D). The competitive binding assay was carried out with 22 concentrations of unlabelled insulin. Binding data were analysed by a non-linear direct model fitting procedure assuming one non-cooperative binding site. Maximum specific binding was unchanged in the total collective of gestational diabetic women, but was decreased by 30% in those treated with diet (6.2±2.2%) and increased by 90% in insulin-treated women (16.4±10.2%) as compared to the control subjects (8.7±2.5%). The diet-treated women had only 40% as many and those treated with insulin had more than twice as many receptors compared to control subjects on a per mg protein basis and if expressed per total placenta. In patients with overt diabetes mellitus maximum specific binding (18.5±10.6 %) was higher (p<0.05) due to more receptors compared to control subjects but was similar to the insulin-treated gestational diabetic patients. Maximum specific binding and receptor concentrations did not correlate linearly with maternal plasma insulin levels. Receptor affinities were virtually similar in all groups (1.8·109 l/mol). The placental glycogen content was reduced (p<0.05) to about 80% of that of control subjects in the diet-treated collective, whereas it was unchanged compared to control subjects in the insulin-treated gestational diabetic women despite a 40% increase (p<0.001) of the maternal-to-cord serum glucose ratio. In overt diabetic patients the maternal-to-cord serum glucose ratio and the placental glycogen content were higher (p<0.05) than in the control subjects. We conclude that trophoblast plasma membranes from gestational diabetic women treated with diet alone express less and those from women treated with insulin express more insulin receptors than those from a healthy control group in vitro. These differences could not have been disclosed without consideration of the mode of treatment. Trophoblast plasma membranes from overt diabetic women have more insulin receptors than those from healthy control subjects. 相似文献
67.
Summary The metabolic potency of recombinant human insulin-like growth factor II was studied in anaesthetized adult rats by obtaining dose-response curves for the hypoglycaemic action and for the stimulation of glucose metabolism during euglycaemic clamping. Compared to insulin, about 50 times higher doses of insulin-like growth factor II were required to result in identical in vivo responses, with half-maximally effective serum concentrations for the stimulation of glucose disposal during clamp studies of about 0.8 and 50 pmol/ml, respectively. A similar difference in potency was observed for the dose-dependent stimulatory actions on glucose metabolism in individual target tissues. Half-maximally effective serum concentrations in the range of 0.8 to 3.0 pmol/ml for insulin and of 40 to 70 pmol/ml for insulin-like growth factor II were seen to be required for 2-deoxyglucose uptake, glycogen formation in skeletal muscle and lipogenesis in epididymal fat. Maximal responses were identical with both peptides. These data suggest that in vivo acute metabolic actions of insulin-like growth factor II on carbohydrate metabolism occurred through insulin receptors. 相似文献
68.
目的:观察体外循环(CPB)对10例瓣膜置换术病人全血细胞胰岛素受体和红细胞ATP含量的影响。方法:利用放射配体结合试验,测定全血细胞胰岛素受体密度和亲和力;用高效液相色谱法测定红细胞ATP含量,同时监测血糖和胰岛素浓度。结果:转流30分钟,血细胞高亲和胰岛素受体(R1)密度明显增加(P<0.01),亲和力(K1)明显降低(P<0.01),低亲和胰岛素受体(R2)密度也明显增加(P<0.01),但亲和力(K2)变化不大(P>0.05);停机30分钟,上述变化有所恢复,但未到转流前的水平。转流30分钟红细胞ATP含量明显降低(P<0.01),并持续到停机后30分钟,同时伴随血糖明显升高(P<0.01),胰岛素/血糖比值明显降低(P<0.01)。结论:CPB可致血细胞胰岛素受体密度增加而亲和力下降,以及红细胞ATP含量下降。 相似文献
69.
70.
血清瘦素水平的影响因素及相关性分析 总被引:7,自引:3,他引:4
目的探讨血清瘦素水平的影响因素及相关性分析.方法从2003年3~8月门诊体验人群中随机抽取标本150人,并排除糖尿病及高血压,测定FBS、血脂水平、血清瘦素水平(LEP)、胰岛素水平(INS),瘦素、胰岛素测定均采用放射免疫方法.胰岛素敏感性以敏感指数(IAI)评价.结果血清瘦素水平女性明显高于男性;相关分析显示血清瘦素水平与性别(SEX)、年龄(AGE)、体重指数(BMI)、INS显著正相关(r分别为0.429,0.329,0.249,0.322,P<0.05);与LOGIAI显著负相关(r=0.322,P<0.05),与TC,TG无明显相关;在调整年龄、BMI后,多远逐步回归分析显示血清瘦素水平仍与INS,LOGIAI显著相关.结论血清瘦素水平与TC,TG均无相关,提示高脂血症患者血清瘦素水平与正常人群比较无明显改变;血清瘦素水平与LOGIAI负相关,高瘦素水平人群胰岛素敏感性降低、存在胰岛素抵抗,提示瘦素-胰岛素轴的存在,瘦素是胰岛素抵抗的一个独立危险因素.肥胖患者存在高瘦素血症、瘦素抵抗.如果能弄清瘦素、胰岛素抵抗、肥胖之间的相互作用关系及因果关系,可能对瘦素抵抗、胰岛素抵抗相关痰病的防治有一定的意义. 相似文献