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1.
Objectives : To determine the prevalence of the metabolic syndrome across age strata and cardiorespiratory fitness (CRF) levels in women. Research Methods and Procedures : 7104 women underwent a physical examination, including a maximal treadmill exercise test. Participants were divided into CRF quintiles according to age. The metabolic syndrome was identified using Adult Treatment Panel‐III Guidelines. Tests for trend were performed on demographic variables across CRF quintiles, as well as prevalence of the metabolic syndrome across CRF quintiles, age strata, and maximal workload achieved [maximal metabolic equivalent (MET) level]. Results : The overall prevalence of the metabolic syndrome was 6.5%. Age‐ and smoking‐adjusted prevalence was lower across quintiles of CRF (19.0%, 6.7%, 6.0%, 3.6%, and 2.3% for quintiles I to V, respectively, p for trend = 0.001). Smoking‐adjusted prevalence of the metabolic syndrome was higher across age strata (2.4%, 2.7%, 6.4%, 8.7%, 15.3%, and 16.1% for ages 20 to 29, 30 to 39, 40 to 49, 50 to 59, 60 to 69, and 70 to 80, respectively, p for trend = 0.001). Prevalence of the metabolic syndrome in the different age groups for women who achieved a maximal MET level of 11 or higher was one‐third to one‐fourth that of women who achieved lower maximal MET levels. Discussion : Prevalence of the metabolic syndrome was markedly lower across progressively higher levels of CRF in women of different age strata. Because regular physical activity improves components of the metabolic syndrome, modest increases in CRF among low fit women may ameliorate the metabolic syndrome in some instances.  相似文献   

2.
Objective: To investigate whether the association between BMI and all‐cause mortality could be disentangled into opposite effects of body fat and fat‐free mass (FFM). Research Methods and Procedures: All‐cause mortality was studied in the Danish follow‐up study “Diet, Cancer and Health” with 27, 178 men and 29, 875 women 50 to 64 years old recruited from 1993 to 1997. By the end of year 2001, the median follow‐up was 5.8 years, and 1851 had died. Body composition was assessed by bioelectrical impedance. Cox regression models were used to estimate the relationships among body fat mass index (body fat mass divided by height squared), FFM index (FFM divided by height squared), and mortality. All analyses were adjusted for smoking habits. Results: Men and women showed similar associations. J‐shaped associations were found between body fat mass index and mortality adjusted for FFM and smoking. The mortality rate ratios in the upper part of body fat mass were 1.12 per kg/m2 (95% confidence interval: 1.07, 1.18) in men and 1.06 per kg/m2 (95% confidence interval: 1.02, 1.10) in women. Reversed J‐shaped associations were found between FFM index and mortality with a tendency to level off for high values of FFM. Discussion: Our findings suggest that BMI represents joint but opposite associations of body fat and FFM with mortality. Both high body fat and low FFM are independent predictors of all‐cause mortality.  相似文献   

3.
Objective: To examine whether cardiorespiratory fitness is associated with health risk factors, independent of abdominal obesity (waist circumference). Research Methods and Procedures: Data from 141 40‐year‐old Flemish male subjects were used in a cross‐sectional design. The main outcome measure in this study was the health risk profile, composed of lipid parameters, blood pressure, and body composition parameters. Data were analyzed by regression analysis and by means of analysis of covariance with waist circumference (WC) as covariate and cardiorespiratory fitness as source of variance. Results: The data demonstrated that cardiorespiratory fitness was significantly associated with triglycerides, with the ratio of total cholesterol/serum high density lipoprotein cholesterol, and with percent body fat, independent of an association with WC. Discussion: Major findings of the present cross‐sectional study indicate that a high WC is associated with adverse health‐related lipid profile and body composition characteristics and that relatively high levels of aerobic fitness attenuate the health risk associated with a large WC.  相似文献   

4.
Objective: This study aims to examine the association between various measures of adiposity and all‐cause mortality in Swedish middle‐aged and older men and women and, additionally, to describe the influences of age and sex on these associations. Research Methods and Procedures: A prospective analysis was performed in a cohort of 10,902 men and 16,814 women ages 45 to 73 years who participated in the Malmö Diet and Cancer Study in Sweden. Baseline examinations took place between 1991 and 1996, and 982 deaths were documented during an average follow‐up of 5.7 years. All‐cause mortality was related to the following variables measured at baseline: body mass index (BMI), percentage of body fat, lean body mass (LBM), and waist‐to‐hip ratio (WHR), with adjustment for age and selected covariates. Body composition data were derived from bioelectrical impedance analysis. Results: The association between percentage of body fat and mortality was modified by age, particularly in women. For instance, fatness was associated with excess mortality in the younger women but with reduced mortality in the older women. Weaker associations were seen for BMI than for percentage of body fat in both sexes. Placement in the top quintiles of waist‐to‐hip ratio, independent of overall body fat, was a stronger predictor of mortality in women than in men. The observed associations could not be explained by bias from early death or antecedent disease. Discussion: The findings reveal sex and age differences for the effects of adiposity and WHR on mortality and indicate the importance of considering direct measures of adiposity, as opposed to BMI, when describing obesity‐related mortality risks.  相似文献   

5.
Objective: To examine the relationship between self‐reported body mass index (BMI) and health‐related quality of life in the general adult population in the United States. Research Methods and Procedures: Using data from 109,076 respondents in the 1996 Behavioral Risk Factor Surveillance System, we examined how self‐reported BMI is associated with five health‐related quality of life measures developed by the Centers for Disease Control and Prevention for population health surveillance. Results: After adjusting for age, gender, race or ethnicity, educational attainment, employment status, smoking status, and physical activity status, participants with a self‐reported BMI of <18.5 kg/m2 and participants with a self‐reported BMI of ≥30 kg/m2 reported impaired quality of life. Compared with persons with a self‐reported BMI of 18.5 to <25 kg/m2, odds ratios (ORs) of poor or fair self‐rated health increased among persons with self‐reported BMIs of <18.5 (1.57, 95% confidence interval [CI]: 1.31 to 1.89), 25 to <30 kg/m2 (1.12, 95% CI: 1.04 to 1.20), 30 to <35 kg/m2 (1.65, 95% CI: 1.50 to 1.81), 35 to <40 kg/m2 (2.58, 95% CI: 2.21 to 3.00), and ≥40 kg/m2 (3.23, 95% CI: 2.63 to 3.95); ORs for reporting ≥14 days of poor physical health during the previous 30 days were 1.44 (95% CI: 1.21 to 1.72), 1.04 (95% CI: 0.96 to 1.14), 1.32 (95% CI: 1.19 to 1.47), 1.80 (95% CI: 1.52 to 2.13), and 2.37 (95% CI: 1.90 to 2.94), respectively; ORs for having ≥14 days of poor mental health during the previous 30 days were 1.18 (95% CI: 0.97 to 1.42), 1.02 (95% CI: 0.95 to 1.11), 1.22 (95% CI: 1.10 to 1.36), 1.68 (95% CI: 1.42 to 1.98), and 1.66 (95% CI: 1.32 to 2.09), respectively. Discussion: In the largest study to date, low and increased self‐reported BMI significantly impaired health‐related quality of life. Particularly, deviations from normal BMI affected physical functioning more strongly than mental functioning.  相似文献   

6.
CrossFit is becoming increasingly popular as a method to increase fitness and as a competitive sport in both the Unites States and Europe. However, little research on this mode of exercise has been performed to date. The purpose of the present investigation involving experienced CrossFit athletes and naïve healthy young men was to investigate the relationship of aerobic capacity and anaerobic power to performance in two representative CrossFit workouts: the first workout was 12 minutes in duration, and the second was based on the total time to complete the prescribed exercise. The participants were 32 healthy adult males, who were either naïve to CrossFit exercise or had competed in CrossFit competitions. Linear regression was undertaken to predict performance on the first workout (time) with age, group (naïve or CrossFit athlete), VO2max and anaerobic power, which were all significant predictors (p < 0.05) in the model. The second workout (repetitions), when examined similarly using regression, only resulted in CrossFit experience as a significant predictor (p < 0.05). The results of the study suggest that a history of participation in CrossFit competition is a key component of performance in CrossFit workouts which are representative of those performed in CrossFit, and that, in at least one these workouts, aerobic capacity and anaerobic power are associated with success.  相似文献   

7.
8.
Hamilton's original work on inclusive fitness theory assumed additivity of costs and benefits. Recently, it has been argued that an exact version of Hamilton's rule for the spread of a pro‐social allele (rb > c) holds under nonadditive pay‐offs, so long as the cost and benefit terms are defined as partial regression coefficients rather than pay‐off parameters. This article examines whether one of the key components of Hamilton's original theory can be preserved when the rule is generalized to the nonadditive case in this way, namely that evolved organisms will behave as if trying to maximize their inclusive fitness in social encounters.  相似文献   

9.
Objective: To clarify the associations between obesity and health‐related quality of life by exploring the associations between physical and emotional well‐being in relation to obesity and the presence of other chronic illness. Research Methods and Procedures: The study data were collected as part of a postal‐survey within the old Oxford Regional Health Authority of England in 1997. Completed questionnaires were returned by 8889 of 13,800 randomly selected adults aged 18 to 64 years. The main outcome measures were body mass index in five categories (underweight, normal weight, overweight, moderately obese, morbidly obese); chronic illness status (any vs. none and number of such illnesses 0, 1 to 2, 3+); and mean SF‐36 questionnaire score in two summary component measures reflecting physical and emotional well‐being. Results: Of the subjects, 31% were overweight and an additional 11% were obese. Body mass index was significantly associated with health status, but the pattern varied according to whether the measure reflected physical or emotional well‐being. Physical, but not emotional, well‐being deteriorated markedly with increasing degree of overweight and was limited in subjects who were obese but had no other chronic condition; subjects with chronic illnesses other than obesity were compromised in both dimensions. In terms of the number of chronic illnesses reported, the additional presence of obesity was associated with a significant deterioration in physical but not emotional well‐being. Discussion: Overweight and obesity are associated with poor levels of subjective health status, particularly in terms of physical well‐being. The limitations in emotional well‐being that are reported here and in other studies may be a result of confounding by the presence of accompanying chronic illness.  相似文献   

10.
To date, there are virtually no existing data on the relationship between obesity, menopausal status, and breast cancer in African-Americans. Therefore, the present study was designed to test the following hypotheses in an African-American population: (1) there exists a positive association between BMI and breast cancer among postmenopausal women; (2) there exists an inverse association between BMI and breast cancer among premenopausal women; and (3) similar associations between BMI and reproductive factors exist for both pre- and postmenopausal breast cancer cases. The study population comprised 357 African-American women (n=193 breast cancer cases; n=164 controls). No significant differences were observed between premenopausal cases and controls for BMI, obesity categories, and reproductive factors. Among the postmenopausal women, the cases had significantly lower weight and BMI levels than the controls. Age at first pregnancy and parity were significantly lower among postmenopausal cases than their controls. No significant associations were revealed between body mass index and breast cancer for pre- and postmenopausal women. In the present study, early age at menarche was the only reproductive factor that was an independent predictor of BMI for both pre- and postmenopausal women, irrespective of breast cancer status. Also, these findings strongly suggest the need to consider reproductive factors, particularly age at menarche, as a covariate of BMI and other obesity-related diseases.  相似文献   

11.
A meta‐analysis was conducted to explore the risk for cardio‐metabolic abnormalities in drug naïve, first‐episode and multi‐episode patients with schizophrenia and age‐ and gender‐ or cohort‐matched general population controls. Our literature search generated 203 relevant studies, of which 136 were included. The final dataset comprised 185,606 unique patients with schizophrenia, and 28 studies provided data for age‐ and gender‐matched or cohort‐matched general population controls (n=3,898,739). We found that multi‐episode patients with schizophrenia were at increased risk for abdominal obesity (OR=4.43; CI=2.52‐7.82; p<0.001), hypertension (OR=1.36; CI=1.21‐1.53; p<0.001), low high‐density lipoprotein cholesterol (OR=2.35; CI=1.78‐3.10; p<0.001), hypertriglyceridemia (OR=2.73; CI=1.95‐3.83; p<0.001), metabolic syndrome (OR=2.35; CI=1.68‐3.29; p<0.001), and diabetes (OR=1.99; CI=1.55‐2.54; p<0.001), compared to controls. Multi‐episode patients with schizophrenia were also at increased risk, compared to first‐episode (p<0.001) and drug‐naïve (p<0.001) patients, for the above abnormalities, with the exception of hypertension and diabetes. Our data provide further evidence supporting WPA recommendations on screening, follow‐up, health education and lifestyle changes in people with schizophrenia.  相似文献   

12.
Parkinson's disease (PD) is generally sporadic but a number of genetic diseases have parkinsonism as a clinical feature. Two dominant genes, α‐synuclein (SNCA) and leucine‐rich repeat kinase 2 (LRRK2), are important for understanding inherited and sporadic PD. SNCA is a major component of pathologic inclusions termed Lewy bodies found in PD. LRRK2 is found in a significant proportion of PD cases. These two proteins may be linked as most LRRK2 PD cases have SNCA‐positive Lewy bodies. Mutations in both proteins are associated with toxic effects in model systems although mechanisms are unclear. LRRK2 is an intracellular signaling protein possessing both GTPase and kinase activities that may contribute to pathogenicity. A third protein, tau, is implicated as a risk factor for PD. We discuss the potential relationship between these genes and suggest a model for PD pathogenesis where LRRK2 is upstream of pathogenic effects through SNCA, tau, or both proteins.  相似文献   

13.
Objective:To examine whether genetic polymorphisms in CYP19 [intron 4 (TTTA)n; n = 7 to 13 and a 3‐base pair deletion, which is in strong linkage disequilibrium with the seven repeat] and COMT (Val108/158Met) modified the change in BMI, total and percentage body fat, or subcutaneous and intra‐abdominal fat during a year‐long exercise intervention trial. These genes metabolize estrogens and androgens, which are important in body fat regulation. Research Methods and Procedures: A randomized intervention trial was used, with an intervention goal of 225 min/wk of moderate‐intensity exercise for one year. Participants (n = 173) were postmenopausal, 50 to 75 years old, sedentary, overweight or obese, and not taking hormone therapy at baseline. Results: Exercisers with two vs. no CYP19 11‐repeat alleles had a larger decrease in total fat (?3.1 kg vs. ?0.5 kg, respectively, p = 0.01) and percentage body fat (?2.4% vs. ?0.6%, respectively, p = 0.001). Exercisers with the COMT Met/Met vs. Val/Val genotype had a smaller decrease in percentage fat (?0.7% vs. ?1.9%, respectively, p = 0.05). Among exercisers, women with the COMT Val/Val genotype and at least one copy of the CYP19 11‐repeat allele vs. those with neither genotype/allele had a significantly larger decrease in BMI (?1.0 vs. +0.1 kg/m2, respectively, p = 0.009), total fat (?2.9 vs. ?0.5 kg, respectively, p = 0.004), and percentage body fat (?2.6% vs. ?0.4%, respectively, p < 0.001). Discussion: Genetic polymorphisms in CYP19 and COMT may be important for body fat regulation and possibly modify the effect of exercise on fat loss in postmenopausal women.  相似文献   

14.
We present a survey of sample size formulas derived in other papers for pairwise comparisons of k treatments and for comparisons of k treatments with a control. We consider the calculation of sample sizes with preassigned per‐pair, any‐pair and all‐pairs power for tests that control either the comparisonwise or the experimentwise type I error rate. A comparison exhibits interesting similarities between the parametric, nonparametric and binomial case.  相似文献   

15.
16.
We present the first ever observations of dwarf crocodiles (Osteolaemus tetraspis) selectively utilizing a cave ecosystem. We analysed crocodile diet to preliminarily assess the degree of ecological isolation of cave‐dwelling crocodiles from their forest‐dwelling conspecifics despite their physical proximity. We additionally conducted the first study of body condition of dwarf crocodiles and compared cave‐dwelling individuals to surface‐dwelling individuals from a variety of alternative habitats and sites as a means to better understand the implications of a semihypogean life on this species. Crocodiles captured in the caves appeared to forage exclusively in the caves and ate mostly cave crickets and bats, whereas crocodiles captured in the surrounding forest habitat consumed primarily freshwater crustaceans and insects and were not found to consume cave‐dwelling prey. Juvenile cave crocodiles had significantly higher body condition compared to juvenile forest crocodiles, which did not vary amongst forest locations. The difference in body condition between adult cave and forest crocodiles was not statistically significant despite also being higher; we suspect this is an artefact of the low sample size rather than a real nondifference. Forest adult crocodiles generally had significantly higher body condition than juveniles, but did not vary by site or habitat. This lack of variation suggests that habitat type is not the most important factor influencing dwarf crocodile body condition. Our results provide a unique insight into facultative cave use by a principally surface‐dwelling species and reinforce the necessity for further research into this unique system to better understand the evolutionary‐scale implications of cave habitat use by dwarf crocodiles.  相似文献   

17.
The chikungunya virus outbreak that occurred in 2007 in northern Italy (Emilia‐Romagna region) prompted the development of a large scale monitoring system of the population density of Aedes albopictus (Skuse, 1894), comparable at the provincial and municipal levels. In 2007, egg density data presented an aggregated distribution (VMR >1) and Taylor's power law was applied to calculate the minimum number of ovitraps needed to obtain the prefixed precision levels: D=0.2 in the areas where the chikungunya epidemic occurred and D=0.3 in all the other urban areas >600 ha. The estimated minimum ovitrap number was then used to set up a monitoring network at the regional scale in season 2008 (May‐October). In 242 municipalities 2,741 ovitraps were activated and the 2008 sampled data showed a similar aggregated distribution as in 2007. The adequacy of the monitoring design was evaluated by recalculating the Taylor's coefficients and the minimum ovitrap number for each urban area >600 ha using the 2008 egg density data. The comparison between the two estimates showed that the minimum ovitrap number calculated in 2007 was underestimated by 2.7% in weeks 22–41 but was overestimated by 29.4% if referring to the period of highest population density (weeks 27–37). The low cost of the proposed monitoring system, based on the use of fortnightly checked ovitraps, could make it economically sustainable even in a non‐epidemic season.  相似文献   

18.
19.
The subject of this article is a search for the long‐term immunological effects of alloferon and 3 structural analogues of alloferon, which were earlier characterized by the highest pro‐apoptotic activity in Tenebrio molitor. The differences in the actions of these peptides on immune response were observed. Alloferon increased nodulation and significantly phenoloxidase activity in the hemolymph of experimentally infected T. molitor. However, [Phe(p‐NH2)1]‐ and [Phe(p‐OMe)1]‐alloferon strongly inhibited cellular and humoral defense of the mealworm against Staphylococcus aureus infection. One day after injection of these peptides, the specific biochemical and morphological hallmarks of apoptosis in bacteria‐challenged hemocytes were visible; in contrast, 3 days after peptides injection in all hemocytes, caspase activation was not observed. However, these new, circulating hemocytes differed from the control and the peptide‐untreated bacteria‐challenged hemocytes. They had an increased adhesion that led to a separation of viable, anucleated fragments of hemocytes that retain the ability to adhere and to form long filopodia. The peptide‐induced separation of hemocyte fragments may resemble the formation of platelets in mammals and perhaps play a role in sealing wounds in insects. The results of in vivo studies may suggest a long half‐life of studied peptides in the hemolymph of mealworm. Moreover, we showed the importance of the N‐terminal histidine residues at position one of the alloferon molecule for its immunological properties in insects. The results obtained here show that alloferon plays pleiotropic functions in insects.  相似文献   

20.
On‐column reaction gas chromatography combines the power of separation and rapid analysis of reactants and reaction products with screening of reactions in a single step. Not only conversions but the reaction rates at various temperatures can be obtained from single measurements, making this approach superior to the time‐consuming measurements typically performed in reaction progress analysis. However, this approach has only been used in the investigation of interconversion processes, rearrangement reactions, and only a few examples of higher‐order reactions are known. Here we present the screening of immobilized gadolinium(III)‐tris[(1R,4S)‐3‐heptafluorobutanoyl‐camphor] in the Danishefsky‐hetero‐Diels‐Alder‐reaction by enantioselective on‐column reaction gas chromatography utilizing cryogenic focusing to achieve catalytic conversions in this higher‐order reaction and subsequent separation of the enantiomeric product mixture to determine the enantiomeric ratio. The results obtained by this approach could be transferred to the conventional batch reaction at a larger scale, demonstrating that on‐column reaction chromatography provides reliable results in the screening of enantioselective reactions. Chirality 26:243–248, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

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