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131.
Summary In a nationwide incident case-referent study stepwise univariate analysis has revealed several risk determinants for childhood diabetes mellitus. In a multivariate analysis we have determined the set of risk determinants that would independently predict childhood Type 1 (insulin-dependent) diabetes. Possible interactions between the risk determinants and differences in risk profiles with different ages at onset were also examined. Reported familial insulin-treated and non-insulin-treated diabetes were significant risk factors in all age groups, as was also a low frequency of milk intake. The frequency of infections and a high intake of foods rich in nitrosamine tended to interact (OR 11.8, p=0.053) indicating a synergistic effect. A Cox regression analysis revealed that stressful life events during the last year was the only variable that tended to affect the age at onset (p=0.055). This indicated that psychological stress may rather precipitate than induce Type 1 diabetes. A short breast-feeding duration (OR=3.81), and an increased body height (OR=3.82) contributed significantly to the predictive model in only the youngest age group (0–4 years). An increased frequency of infections in the year preceding onset (OR=2.15) and no vaccination against measles (OR=3.33) contributed significantly to the model only in the age group 5–9 years. Various nutrients had different impacts on the risk of developing Type 1 diabetes in different age groups. It is concluded that in the genetically susceptible child, risk factors which are associated with eating habits, frequency of infections, vaccination status, growth pattern and severe psychological stress affect the risk of developing diabetes independently of each other. The set of risk determinants varies with the age at onset. A high frequency of infections and a high frequency of nitrosamine-rich food intake seem to have a synergistic effect on the risk of developing diabetes in childhood.  相似文献   
132.
2型糖尿病患者载脂蛋白E基因多态性的研究   总被引:2,自引:0,他引:2  
目的:探讨中国人2型糖尿病患者载脂蛋白E(apoE)基因多态性及其与血脂和载脂蛋白水平的关系。方法:采用聚合酶链反应-限制性酶切片段长度多态性法,分别对74例2型糖尿病患者及191例血脂、血糖正常且无糖尿病史者的apoE基因型、空腹血脂及载脂蛋白AI、AⅡ、B100、CⅡ、CⅢ及E进行全面分析。结果:2型糖尿病患者的血清甘油三酯(TG)、总胆固醇(TC),低密度脂蛋白胆固醇(LDLC),非高密度脂蛋白胆固醇(nHDLC),载脂蛋白B100、CⅡ、CⅢ、E水平及TG/HDLC比值较对照组显著升高(P<0.01);血清高密度脂蛋白胆固醇(HDLC),apoE/apoCⅢ比值显著降低(P<0.05)。2型糖尿病组与对照组apoE基因频率分布无显著性差异(P>0.05)。携带ε2等位基因组血清TG/HDLC比值较E3/3基因型显著降低;而携带ε4等位基因组血清apoAⅡ水平较E3/3基因型及携带ε2等位基因组显著升高(P<0.001)。结论:2型糖尿病患者apoE基因多态性与血TG/HDLC及apoAⅡ有一定关联。  相似文献   
133.
MRI of the brain in diabetes mellitus   总被引:15,自引:0,他引:15  
We studied the MRI appearances of the brain in 159 patients with diabetes mellitus (DM) and 2566 agematched individuals without DM (controls). The images were reviewed for cerebral infarcts, hemorrhage, atrophy and subcortical arteriosclerotic encephalopathy. Cerebral atrophy was significantly more frequent in patients with DM than in controls (P>0.005) from the sixth to the eighth decade. The frequency of atrophy was 41.2% in the 6th decade, 60.0% in the 7th and 92.3% in the 8th decade in DM, and 19.8%, 38.9% and 56.8% respectively in controls. Unexpectedly, there was no statistically significant difference in the incidences of cerebrovascular diseases at any age.  相似文献   
134.
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   
135.
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   
136.
缬沙坦对糖尿病大鼠心肌MCP-1表达的影响   总被引:2,自引:0,他引:2  
目的 研究缬沙坦对糖尿病大鼠心肌MCP -1表达的影响。方法 将Wistar大鼠随机分成三组 :正常对照组 (NC组 )、糖尿病模型组 (DM组 )、糖尿病模型 +缬沙坦治疗组 (DV组 ) ,用STZ诱导糖尿病大鼠模型 ,于 8周后用免疫组织化学的方法检测糖尿病大鼠和缬沙坦干预的糖尿病大鼠心肌组织中MCP -1的表达。结果  8周时心肌组织中MCP -1的表达DM组明显高于DV组、NC组 (P <0 0 1) ,DV组明显高于NC组 (P <0 0 1)。结论 缬沙坦能显著减少糖尿病大鼠心肌组织中MCP -1的表达  相似文献   
137.
We present our experience with twenty children with insulin dependent diabetes mellitus admitted during the past 2 1/2 years. Sixteen patients were admited with acute onset of ketoacidosis while four were having gradual onset. Active and symptomatic treatment was started in all diabetic ketoacidotic patients. One patient died during the acute stage. Eleven patients were followed for 3–6 months or more. Glycosylated hemoglobin was considered as a criteria for control. Three had good control, two fair and six poor control; six developed diabetic ketoacidosis and three developed hypoglycemia  相似文献   
138.
目的 对比观察2型糖尿病(DM)及糖尿病肾病(DN)患者血管内皮损害标志物,分析其与白蛋白尿相关性。方法 6 8例2型糖尿病患者根据尿白蛋白排泄率分为正常白蛋白尿组(Ⅰ组)和微量白蛋白尿组(Ⅱ组) ,同时以健康成人作为对照组(Ⅲ组) ,分别检测其循环内皮细胞(CEC)、vonWillebrand因子(vWF)、内皮素- 1 (ET - 1 )的变化,并分析其相关性。结果 DM患者CEC、vWF和ET - 1明显增高,尤其是DN组(P <0 .0 5 ) ,各指标间以及与尿白蛋白排泄呈正相关。结论 2型DM患者在出现白蛋白尿前已存在血管内皮功能异常,其白蛋白排泄与血管内皮功能障碍程度有一定相关性。  相似文献   
139.
The presence or absence of retinal detachment, especially detachment of the macula, was the most critical parameter predicting visual outcome, and long duration of detachment worsened the prognosis (P=0.0084). In contrast, the time interval from vitreous haemorrhage to surgery did not associate with the long-term visual outcome. Pre-operative visual acuity of counting fingers 1 m or better was associated with favourable visual outcome (P=0.0032). Other pre- or per-operative parameters (e.g. aphakia, iris rubeosis, extent of photocoagulation, retinal breaks) did not associate with visual prognosis significantly.Significant association between general parameters and visual outcome was found only in the group of traction retinal detachment where loss of vision was related to shorter duration of diabetes (P=0.0213), and shorter duration of background retinopathy (P=0.0300), and proliferative retinopathy (P=0.0072).  相似文献   
140.
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