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1.
The Transmission Disequilibrium Test (TDT) detects linkage between a marker and a disease-susceptibility locus in the presence of linkage disequilibrium. The TDT requires data on the genotypes of affected offspring and their parents, which might not always be available. For example, for late onset diseases it might be difficult to find parents still alive, or genotypes of offspring might not be available. Genotyping unaffected siblings, combining different genotype data sets, or assuming a model mechanism for missing parents have all been proposed to deal with missing genotypes in parents but not in offspring. In this paper, we propose a Mendel Inheritance-Transmission Disequilibrium Test (MI-TDT) to impute missing genotypes in any members of a family with two affected offspring. Our method does not require any of the remedies mentioned above but simply utilizes the fundamental property of Mendel Inheritance on the transmission of alleles from parents to offspring. Most importantly, the MI-TDT reassures researchers about the declared significant genes when incomplete data is ignored. We illustrate the MI-TDT by identifying significant genes in type 1 diabetes from the Warren families in the United Kingdom.  相似文献   
2.
文成勇 《激光杂志》2013,(6):124-125
目的:利用血管回声跟踪技术(ET)研究糖尿病(DM)患者颈动脉弹性与下肢动脉粥样硬化病变的相关性。方法:选择116例糖尿病患者分别进行颈动脉弹性检查和下肢血管彩超检查,根据血管彩超检查结果分为无下肢动脉粥样硬化病变组(对照组A)和下肢动脉粥样硬化病变组,下肢动脉粥样硬化病变组又根据下肢动脉血管的狭窄程度由轻至重依次分为B、C、D、E四组。分析比较各组间应用髓检查获得的颈动脉弹性参数,即压力应变弹性系数(Ep)、僵硬度(β)、顺应性(AC)、增大指数(AI)、脉冲波传导速度(PWVβ)。结果:下肢动脉粥样硬化病变组Ep取PWvp值较对照组明显增高,Ac值较对照组明显降低,差异有统计学意义(P〈0.01或P〈0.05),随着各组间下肢动脉病变程度的不断加重,Ep取Pw邯值增加明显,差异有统计学意义(P〈0.01或P〈0.05),参数AI在各组间差异无统计学意义(P〉0.05)。结论:血管回声跟踪技术能揭示糖尿病患者颈动脉弹性参数与下肢动脉粥样硬化病变程度的相关性,是评价糖尿病下肢动脉粥样硬化病变的有效方法。  相似文献   
3.
Recent reports on cocoa are appealing in that a food commonly consumed for pure pleasure might also bring tangible benefits for human health. Cocoa consumption is correlated with reduced health risks of cardiovascular diseases, hypertension, atherosclerosis, and cancer, and the health-promoting effects of cocoa are mediated by cocoa-driven phytochemicals. Cocoa is rich in procyanidins, theobromine, (?)-epicatechin, catechins, and caffeine. Among the phytochemicals present in consumed cocoa, theobromine is most available in human plasma, followed by caffeine, (?)-epicatechin, catechin, and procyanidins. It has been reported that cocoa phytochemicals specifically modulate or interact with specific molecular targets linked to the pathogenesis of chronic human diseases, including cardiovascular diseases, cancer, neurodegenerative diseases, obesity, diabetes, and skin aging. This review summarizes comprehensive recent findings on the beneficial actions of cocoa-driven phytochemicals in molecular mechanisms of human health.  相似文献   
4.
癞葡萄降糖活性成分的提取及其降糖活性的研究   总被引:6,自引:0,他引:6  
对癞葡萄中水溶性降糖活性成分的提取进行了研究.以水作为溶剂提取癞葡萄的降糖活性成分,通过10kdal的超滤膜将水提物分为二个组分,并对这两个组分分别进行了降糖活性动物实验.结果表明,大、小分子组分均有一定降糖效果,但相对分子量大于10kdal的组分降糖效果不显著;相对分子量小于10kdal的组分降糖活性显著,起着主要的降糖作用.  相似文献   
5.
The thermal inactivation conditions (75 °C × 35 min, 80 °C × 10 min, 85 °C × 5 min and 90 °C × 5 min) for Protamex? following bovine whey protein concentrate (WPC) hydrolysis was studied with the view to limiting WPC hydrolysate (WPH) aggregation while maintaining bioactivity. A decrease in the amount of large WPH aggregates formed was observed at inactivation temperatures ≤85 °C. However, the WPC appeared to be more hydrolysed on heating at 75 °C × 35 min, as Protamex? was active for longer under these heating conditions. Significantly (< 0.05), higher WPH antioxidant (oxygen radical absorbance capacity – ORAC) activity was obtained on inactivation at temperatures ≤80 °C. In contrast, the dipeptidyl peptidase IV (DPP‐IV) inhibitory properties of all WPH samples were similar (> 0.05). A reduction in thermal treatment from 90 °C × 5 min to 85 °C × 5 min was sufficient to decrease the amount of large aggregates formed in the hydrolysate without altering its bioactive properties.  相似文献   
6.
Coffee is a complex mixture of chemicals that provides significant amounts of chlorogenic acid and caffeine. Unfiltered coffee is a significant source of cafestol and kahweol, which are diterpenes that have been implicated in the cholesterol-raising effects of coffee. The results of epidemiological research suggest that coffee consumption may help prevent several chronic diseases, including type 2 diabetes mellitus, Parkinson's disease and liver disease (cirrhosis and hepatocellular carcinoma). Most prospective cohort studies have not found coffee consumption to be associated with significantly increased cardiovascular disease risk. However, coffee consumption is associated with increases in several cardiovascular disease risk factors, including blood pressure and plasma homocysteine. At present, there is little evidence that coffee consumption increases the risk of cancer. For adults consuming moderate amounts of coffee (3-4 cups/d providing 300-400 mg/d of caffeine), there is little evidence of health risks and some evidence of health benefits. However, some groups, including people with hypertension, children, adolescents, and the elderly, may be more vulnerable to the adverse effects of caffeine. In addition, currently available evidence suggests that it may be prudent for pregnant women to limit coffee consumption to 3 cups/d providing no more than 300 mg/d of caffeine to exclude any increased probability of spontaneous abortion or impaired fetal growth.  相似文献   
7.
马齿苋多糖对糖尿病大鼠血液生化指标的影响   总被引:2,自引:0,他引:2  
目的:研究马齿苋多糖对糖尿病大鼠血液生化指标的影响。方法:将Wistar大鼠造模后随机分为正常对照组、模型对照组、马齿苋多糖大、中、小剂量[400、200、100mg/(kg·d)]组治疗4周后。检测空腹血糖、血脂、血清中胰岛素水平、c肽和糖化血红蛋白的变化。结果:马齿苋多糖大、中剂量治疗组可以明显降低血糖、血脂及胰岛素敏感性(P〈0.01),明显增高胰岛素敏感指数(ISI)(P〈0.01)。结论:马齿苋多糖具有降低糖尿病大鼠血糖水平、改善机体胰岛素敏感性、调节血脂紊乱的功能。  相似文献   
8.
Ⅱ型糖尿病是一种常见的慢性代谢性疾病,其发病机制十分复杂,其中肠道菌群在其发病早期和加重过程中都起着重要的作用。益生菌作为调节肠道菌群的有效手段,可以通过改善肠道通透性、调节血脂、增强机体免疫力等多种机制对II型糖尿病起到预防和改善作用。现就近年来肠道菌群和2型糖尿病的相关性以及益生菌的作用研究进展作一综述。  相似文献   
9.
A fibre‐enriched, reduced‐calorie biscuit [formulated biscuit (FB)] was evaluated for its antidiabetic and antilipidaemic potential in streptozotocin‐induced diabetes in Wistar rats against control biscuit (CB) having high calorie and low fibre content. Animals were allocated into five groups: a control group fed with synthetic diet, two diabetes‐induced groups (CBD and FBD) and two nondiabetic groups (CBND and FBND). CBD and CBND were fed with synthetic diet + CB while FBD and FBND were fed with synthetic diet + FB. After 6 weeks of feeding, the change in weight of nondiabetic group fed with FB (+16.20%) was nonsignificantly lower compared to control (+33.01%) and CB‐fed (+34.55%) group. Nonsignificant loss in body weight was observed among diabetic group fed with FB (?11.76%) or CB (?36.88%). Feeding of FB led to a significant decrease in fasting and postprandial blood glucose levels, total cholesterol, triglycerides, LDL‐C, VLDL‐C and atherosclerotic index and increase the HDL‐C. Histological examination showed that feeding of FB was able to partially recover the destroyed β‐cell in STZ‐induced diabetic rats.  相似文献   
10.
药物联合饮食控制、运动疗法治疗糖尿病的临床价值研究   总被引:1,自引:0,他引:1  
目的:研究药物联合饮食控制、运动疗法治疗社区糖尿病患者的临床效果,总结其临床价值。方法:选取80例社区糖尿病患者,按随机数字表法将其分成实验组40例、对照组40例,给予对照组患者常规治疗及健康宣教,在此基础上为实验组患者联合应用饮食控制及运动疗法治疗,统计两组血糖控制效果。结果:治疗结束后,实验组总胆固醇、甘油三酯、糖化血红蛋白、空腹血糖、餐后2h血糖水平分别为1.48±0.19mg/dL、0.79±0.13mg/dL、(4.96±0.71)%、5.04±1.75mmol/L、7.40±1.60mmol/L,以上观察指标均优于对照组,此外,实验组患者血糖控制有效率显著高于对照组(97.5%VS 85.0%,P0.05)。结论:药物联合饮食控制、运动疗法是控制糖尿病患者血糖的有效方法,具有较高的临床应用价值,可进一步在临床上推广。  相似文献   
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