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991.
高胰岛素正糖钳夹技术可以测定活体的胰岛素敏感性,但它并不适用于大规模流行病学研究。流行病学研究需要简单的胰岛素抵抗测定法。本文补充报告在空腹血糖(FPG)(75~306mg/dl或4.2~17.1mmol/L)及空腹胰岛素(FIns)(9.7~120mU/L)范围很宽的Pima印第安人群中,正糖钳夹技术测定的胰岛素介导的葡萄糖代谢率(M)与涉及FPG、FIns的多种复合的胰岛素敏感指数的相关性:胰岛素作用指数(IAI)=1/(FPG×FIns)在非糖尿病人群及2型糖尿病人群都与M显著正相关(r>0.7,P=0.0001),而且这两者的相关性强于M与其他指数如FIns或FPG/FIns比值的相关性,也不弱于M与糖负荷后3~5个时间点的血糖、胰岛素曲线下面积乘积的相关性。IAI的五分变量分布情况表明有90.4%的IAI落在所预测的M值五分变量区域或与之相邻的一个五分变量区域之内。1/FPG×FIns虽相对简单但确实与机体的胰岛素敏感性密切相关,它可以做为胰岛素敏感指数在流行病学研究中应用。  相似文献   
992.
To assess the sensitivity and specificity of the resistive index of the hepatic artery, which is related to the vascular resistance of the artery, for the prediction of fulminant hepatic failure, we performed Doppler ultrasonography examinations on the hepatic arteries of 72 patients with acute viral hepatitis (25 of whom developed fulminant hepatic failure and 47 of whom recovered without developing fulminant hepatic failure) as well as the hepatic arteries of age- and sex-matched controls. The mean resistive index of the hepatic arteries in patients who developed fulminant hepatic failure was significantly larger than that of patients who recovered without developing fulminant hepatic failure (P < 0.01). When a resistive index cutoff level of 0.74 was used, an 84% sensitivity and a 94% specificity were obtained for the prediction of fulminant hepatic failure. An elevated resistive index of the hepatic artery may be useful for predicting the patient's clinical outcome and determining the need for a liver transplantation in patients with acute viral hepatitis.  相似文献   
993.
OBJECTIVES: To investigate the relationship between body mass index (BMI) and 9-year mortality in older (≥65) Americans with and without disability.
DESIGN: Cohort study.
SETTING: The unique disability-focused National Long Term Care Survey (NLTCS) data that assessed the health and well-being of older individuals in 1994 were analyzed.
PARTICIPANTS: Four thousand seven hundred ninety-one individuals in the 1994 survey.
MEASUREMENTS: BMI (kg/m2) was calculated from self- or proxy reports of height and weight. The analysis was adjusted for 1-year change in BMI and demographic and health-related factors, as well as reports by proxies, and death occurring during the first 2 years after the interview.
RESULTS: The relative risk of death as a function of BMI formed a nonsymmetric U-shaped pattern, with larger risks associated with lower BMI (<22.0) and minimal risks for BMI of 25.0 to 34.9. (BMI 22.0–24.9 was the reference.) Adjustments for demographic and health-related factors had little effect on this pattern. Nondisabled individuals exhibited a similar U-shaped pattern but with lower risks associated with lower BMI. For disabled individuals, the mortality–risk pattern was higher for lower BMI (<22.0) and flat for higher BMI, thus exhibiting an inverse J shape. BMI patterns were age sensitive, with disability status affecting sensitivity.
CONCLUSION: Overweight or mild (grade 1) obesity was not a risk factor for 9-year mortality in older Americans participating in the 1994 NLTCS. A flatter BMI pattern of the relative risk of death for disabled than for nondisabled individuals suggests that optimal body weight can be sensitive to age and health and well-being.  相似文献   
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目的 研究多年来老年心脏病手术及手术后监护时,4种药物多输入多输出滴注用模糊逻辑系统的决策制定的原理及方法。方法 从模糊逻辑原理起到4种药物对老年心脏病6种症状的病理状态及治疗策略加以研究。结果 求得典型的模糊逻辑用语言结构,表层结构及电脑用的深度结构。结论 在模糊逻辑理论的概念基础上,可算得模糊化输出,代入病人症状的主要生理参数MAP,MPAD和CO检测值。应用模糊匹配及准则计算的结果就是4种药物多输入多输出滴注时的决策制定成功。以一种狗实验的结论证明此种模糊决策制定模块确能成功应用于临床。  相似文献   
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997.
AimsThe prevalence of metabolic syndrome (MetS) has been increasing in recent years. Investigation of whether consumption of legumes as a part of healthy diet could reduce the odds of MetS has led to inconsistent conclusions. Here, we performed the first meta-analysis of observational studies to analyze the association between legume consumption and prevalence of MetS.Data synthesisPubMed, EMBASE, and Web of Science databases were searched to identify observational studies up to June 1, 2019. We extracted data from the studies included and performed quality assessments. Summary odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using a random-effects model. Publication bias and subgroup and sensitivity analyses were also performed. We finally included four cross-sectional studies, two cohort studies, and one case–control study involving 56,028 participants. The summary OR revealed no statistically significant association between legume consumption and odds of MetS (OR = 0.93, 95% CI = 0.76–1.12, I2 = 73.5%). Subgroup analysis of study characteristics and adjustment for confounding along with sensitivity analyses revealed no statistically significant differences. No evidence of publication bias was detected.ConclusionLegume consumption is not associated with the odds of MetS. These findings require validation in well-designed cohort studies and randomized clinical trials with accurate measurement of legume intake and strict control of confounders.RegistrationThis study was registered with the International Prospective Register of Systematic Reviews (registration number: CRD42019131777).  相似文献   
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1000.

Background and Aims

Physical inactivity, unhealthy diet, smoking and heavy drinking are four key unhealthy lifestyle behaviors (ULB) that may influence body weight and obesity development. More recently, sedentary time has been recognized as another potentially emerging ULB related to obesity. We therefore investigated the association of multiple ULB with overweight/obesity and abdominal obesity among Brazilian adolescents.

Methods and Results

This cross-sectional study involved 62,063 students (12–17 years). Physical inactivity, high screen time, low fiber intake, binge drinking and smoking were self-reported and combined to a ULB risk score, ranging from zero to five. Participants were classified as overweight/obese or with abdominal obesity using sex and age-specific cut-off points for BMI and waist circumference, respectively. Poisson regression models were used to examine the associations between ULB with overweight/obesity and abdominal obesity, adjusted for socio-demographic variables. Overall, 2.3%, 18.9%, 43.9%, 32.3% and 2.6% of participants reported zero, one, two, three and four/five ULB, respectively. Higher ULB risk score was associated with overweight/obesity and abdominal obesity in a dose–response gradient. Among 32 possible combinations of ULB, the three most prevalent combinations (physical inactivity + low fiber intake; high screen time + low fiber intake; physical inactivity + high screen time + low fiber intake) were positively associated with general and abdominal obesity.

Conclusions

Our findings suggest a synergistic relationship between ULB and general and abdominal obesity. Preventive efforts targeting combined ULB should be sought to reduce the prevalence of general and abdominal obesity in Brazilian youth.  相似文献   
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