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排序方式: 共有421条查询结果,搜索用时 15 毫秒
81.
82.
Haerens L Craeynest M Deforche B Maes L Cardon G De Bourdeaudhuij I 《European journal of clinical nutrition》2008,62(1):51-59
OBJECTIVE: The present study aimed at investigating the influence of food availability, rules and television viewing habits on eating behaviours in adolescents. DESIGN: Cross-sectional study. SETTING: Four randomly selected middle schools. SUBJECTS: A sample of 534 seventh and eighth graders. INTERVENTIONS: Validated questionnaires were used to measure the family environment and fat, soft drink and fruit consumption. Hierarchical regression analyses on fat, soft drink and fruit consumption, with demographic and psychosocial variables entered as the first and environmental factors as the second block were conducted in boys and girls. RESULTS: Boys with more unhealthy products available at home consumed more fat (P< or =0.001, 95% CI: 8.2-29.4) and more soft drinks (P< or =0.01, 95% CI: 0.2-1.4). Boys who reported better television viewing habits ate more fruit (P< or =0.001, 95% CI: -1.7 to -0.5). Girls who reported better television viewing habits consumed less fat (P< or =0.01, 95% CI: 1.4-9.0) and more fruit (P< or =0.05, 95% CI: -1.0 to -0.1). Girls who reported higher availability of healthy products at home (P< or =0.05, 95% CI: 0.3-3.1) and more food rules (P< or =0.001, 95% CI: -1.8 to -0.5), consumed more fruit. Environmental factors were poor predictors of soft drink consumption among girls. CONCLUSION: Availability of (un)healthy food products, family food rules and TV viewing habits were related to one or more eating behaviours in boys or girls. Although home environmental factors can play an important role in influencing adolescents' eating behaviours, these factors were generally less predictive than demographic and psychosocial variables. 相似文献
83.
84.
Geldhof E Cardon G De Bourdeaudhuij I Danneels L Coorevits P Vanderstraeten G De Clercq D 《European journal of pediatrics》2006,165(11):779-786
Introduction Based on the literature, reliability reports and normative data for bilateral stance assessments in elementary schoolchildren are limited. The present study was designed to report test-retest reliability and reference values for postural stability in 9 to 10 years old schoolchildren using the Balance Master system.Materials and methods Twenty children participated in the reproducibility study (mean age 10.1±0.7) including test and retest measurement with a one-week interval. The modified clinical test of sensory interaction on balance (mCTSIB) quantified children’s static standing balance. The test for the limits of stability (LOS) measured dynamic standing balance. The study sample to determine reference values consisted of 99 children (mean age 9.8±0.5).Results The ICCs for inter-item reliability of the four sensory conditions of the mCTSIB showed fair to excellent reliability (ICCs between 0.62 and 0.80). The reproducibility between test and retest was non-significant for the condition ‘firm surface with eyes closed’ (ICC of 0.37), fair to good for the three other sensory conditions (ICCs between 0.59 and 0.68), and excellent for the composite sway velocity (ICC of 0.77). For all LOS parameters, the significant ICCs showed fair to good reproducibility (ICCs between 0.44 and 0.62), with the exception of the non-significant ICC for the composite reaction time. The ICCs for the separate LOS parameters showed fair to good and excellent reliability for nine parameters (ICCs between 0.46 and 0.81), while 11 separate LOS scores did not demonstrate significant ICCs.Discussion Analysing reference values, girls performed better on all the composite balance parameters compared to boys, with the exception of reaction time and movement velocity. No differences were found on standing balance scores between 9 and 10 year olds.Conclusion In conclusion, the Balance Master showed fair to good reliability for most postural parameters in 9 to 10 year olds. The current data on postural control in children aged 9 to 10 years are relevant for research in other domains within the clinical field, like obesitas and developmental coordination disorder or in relation to back pain prevalence at early age. 相似文献
85.
A dense set of 5,000 SNPs on a 10-Mb region of human chromosome 20 has been typed on samples of African Americans, East Asians, and United Kingdom Caucasians. There are departures from Hardy-Weinberg equilibrium beyond the level at which markers are often discarded because of possible genotyping errors. The observation that markers showing such departures are often close together on the chromosome confirms the result that Hardy-Weinberg tests at two loci are correlated to an extent that depends on the linkage disequilibrium between those two markers. Linkage disequilibrium can be described by the composite linkage disequilibrium coefficient, the parameter that determines the behavior of case-control allelic tests of association. A useful preliminary investigation of datasets of this type is provided by counting the numbers of distinct multi-locus genotypes in windows of a few markers. 相似文献
86.
87.
A Grau J Pomes A Davalos E Gomez P Sola D Genis 《The Journal of computed tomography》1988,12(2):161-164
We describe a case of acute alcoholic myopathy evaluated by computed tomography. Computed tomography showed a low-density, delimited area in the semimembranous muscle and edema of the subcutaneous cell tissue, permitting determination of the extent of the disease and its localization for purposes of biopsy and fasciotomy of the affected muscle. 相似文献
88.
Firstenberg MS Levine BD Garcia MJ Greenberg NL Cardon L Morehead AJ Zuckerman J Thomas JD 《Journal of the American College of Cardiology》2000,36(5):1664-1669
OBJECTIVES: We sought to determine the relationship between different echocardiographic indices and pulmonary capillary wedge pressures (PCWP) in normal volunteers. BACKGROUND: Indices based on tissue Doppler (TDE) and color M-mode (CMM) echocardiography have been proposed to reflect left (LV) ventricular filling pressures. These include the ratio of early diastolic transmitral velocity (E) to early myocardial velocity measured by TDE (E') and the ratio of E to the wave propagation velocity (Vp) measured from CMM images. These indices, however, have not been validated in normal individuals. METHODS: We studied seven volunteers during two phases of preload altering maneuvers, baseline, with two stages of lower body negative pressure, and repeat baseline with two stages of volume loading. The PCWP obtained from right heart catheterization was compared with diastolic indices using pulsed Doppler, TDE and CMM echocardiography. RESULTS: The PCWP ranged from 2.2 to 23.5 mm Hg. During preload alterations, significant changes in E and septal E' (both p < 0.05) but not lateral E' or Vp were observed. Furthermore, E, septal E' and E/Vp correlated with PCWP (all r > 0.80) but not combined E and TDE indices (both r < 0.15). Within individuals, a similar linear relationship was observed among E/Vp, E and septal E' (average r > 0.80). CONCLUSIONS: In subjects without heart disease, E, septal E' and E/Vp correlate with PCWP. Because the influence of ventricular relaxation is minimized, the ratio E/Vp may be the best overall index of LV filling pressures. 相似文献
89.
To what extent do scans of non-synonymous SNPs complement denser genome-wide association studies? 总被引:3,自引:0,他引:3
Several studies involving genome-wide scans of non-synonymous SNPs (nsSNPs) have successfully identified loci contributing to common complex diseases. We were interested in the extent to which these small scans involving a few thousand non-synonymous markers might complement the results from denser genome-wide association studies. We assessed the degree to which three commercially available genome-wide marker panels tagged nsSNPs on the Illumina HumanNS-12 BeadChip, a product specifically designed to capture non-synonymous variation. We demonstrate that commercially available genome-wide panels already tag the majority of common non-synonymous variants on the NS-12 BeadChip, indicating that with respect to capturing common non-synonymous variation, information from the NS-12 BeadChip is largely redundant. In contrast, genome-wide panels fail to capture most of the rare SNPs present on the NS-12 BeadChip. Power calculations reveal that non-synonymous scans involving sample sizes typical of the current wave of genome-wide association studies are unlikely to identify rare variants of small effect, but could conceivably identify rare variants of intermediate penetrance. We conclude that non-synonymous scans may facilitate the identification of rare variants of intermediate penetrance that would not otherwise be detectable using dense genome-wide panels, but are unlikely to uniquely identify common variants contributing to complex disease variation. 相似文献
90.
van Heel DA McGovern DP Cardon LR Dechairo BM Lench NJ Carey AH Jewell DP 《American journal of medical genetics》2002,111(3):253-259
Crohn disease (CD) is a chronic relapsing inflammatory condition of the gastrointestinal tract. Recently, polymorphisms in NOD2 (CARD15), a gene mapping to the chromosome 16 IBD1 susceptibility locus, have been associated with susceptibility to CD. One group identified the gene by using classic positional cloning methods. Here, we report linkage and fine mapping analyses using 27 microsatellite markers encompassing the IBD1 susceptibility locus in 131 CD affected sibling pairs, and a simplex family cohort. No evidence for linkage was observed, and microsatellite markers close to NOD2 did not show association. However, significant association was confirmed in 294 CD trios for the NOD2 variants Arg702Trp and Leu1007fsinsC. Our fine mapping study of the IBD1 locus did not enable us to identify NOD2 as a CD gene, despite the presence of association with disease-causing alleles. This study illustrates the difficulties facing microsatellite linkage and linkage disequilibrium mapping methods for identifying disease genes in complex traits. 相似文献