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排序方式: 共有157条查询结果,搜索用时 15 毫秒
21.
Haerens L Deforche B Maes L Stevens V Cardon G De Bourdeaudhuij I 《Obesity (Silver Spring, Md.)》2006,14(5):847-854
Objective: To evaluate the effects of a 2‐year middle school physical activity and healthy food intervention, including an environmental and computer‐tailored component on BMI and BMI z‐score in boys and girls. Research Methods and Procedures: A random sample of 15 schools with seventh and eighth graders was randomly assigned to three conditions: an intervention with parental support group, an intervention‐alone group, and a control group. Weight and height were measured at the beginning and end of each school year to assess BMI and BMI z‐score. A physical activity and healthy food program was implemented over 2 school years. Results: In girls, BMI and BMI z‐score increased significantly less in the intervention with parental support group compared with the control group (p < 0.05) or the intervention‐alone group (p = 0.05). In boys, no significant positive intervention effects were found. Discussion: This was the first study evaluating the effectiveness of an intervention combining environmental changes with personal computer‐tailored feedback on BMI and BMI z‐score in middle school children. After 2 school years, BMI and BMI z‐score changed in a more positive direction in girls as a result of the intervention with parental support. 相似文献
22.
A recent study by Cheung et al. demonstrates how to identify expression quantitative trait loci (eQTLs) underlying gene expression phenotypes through a combination of genome-wide linkage analysis and subsequent fine mapping or by genome-wide association (GWA) analysis. This study emphasizes the complexity of human traits, highlighting the challenges faced by investigators--in particular, insufficient linkage disequilibrium between the trait and marker variant, genetic heterogeneity and correcting for multiple testing will all adversely impact the power to detect loci by association. These issues must be considered carefully if the GWA approach is to succeed in mapping complex phenotypes. 相似文献
23.
Benjamin GH Choo Igor Kondrichin Sergey Parinov Alexander Emelyanov William Go Wei-chang Toh Vladimir Korzh 《BMC developmental biology》2006,6(1):5-7
Background
The zebrafish, Danio rerio, is used as a model organism to study vertebrate genetics and development. An effective enhancer trap (ET) in zebrafish using the Tol2 transposon has been demonstrated. This approach could be used to study embryogenesis of a vertebrate species in real time and with high resolution. 相似文献24.
Robert Clarke Peng Xu Derrick Bennett Sarah Lewington Krina Zondervan Sarah Parish Alison Palmer Sarah Clark Lon Cardon Richard Peto Mark Lathrop Rory Collins 《PLoS genetics》2006,2(7)
Lymphotoxin-α (LTA) is a pro-inflammatory cytokine that plays an important role in the immune system and local inflammatory response. LTA is expressed in atherosclerotic plaques and has been implicated in the pathogenesis of atherosclerosis and coronary heart disease (CHD). Polymorphisms in the gene encoding lymphotoxin-α (LTA) on Chromosome 6p21 have been associated with susceptibility to CHD, but results in different studies appear to be conflicting. We examined the association of seven single nucleotide polymorphisms (SNPs) across the LTA gene, and their related haplotypes, with risk of myocardial infarction (MI) in the International Study of Infarct Survival (ISIS) case-control study involving 6,928 non-fatal MI cases and 2,712 unrelated controls. The seven SNPs (including the rs909253 and rs1041981 SNPs previously implicated in the risk of CHD) were in strong linkage disequilibrium with each other and contributed to six common haplotypes. Some of the haplotypes for LTA were associated with higher plasma concentrations of C-reactive protein (p = 0.004) and lower concentrations of albumin (p = 0.023). However, none of the SNPs or related haplotypes were significantly associated with risk of MI. The results of the ISIS study were considered in the context of six previously published studies that had assessed this association, and this meta-analysis found no significant association with CHD risk using a recessive model and only a modest association using a dominant model (with narrow confidence intervals around these risk estimates). Overall, these studies provide reliable evidence that these common polymorphisms for the LTA gene are not strongly associated with susceptibility to coronary disease. 相似文献
25.
26.
Richard GH Immink Isabella AN Tonaco Stefan de Folter Anna Shchennikova Aalt DJ van Dijk Jacqueline Busscher-Lange Jan W Borst Gerco C Angenent 《Genome biology》2009,10(2):R24-16
Background
Plant MADS box proteins play important roles in a plethora of developmental processes. In order to regulate specific sets of target genes, MADS box proteins dimerize and are thought to assemble into multimeric complexes. In this study a large-scale yeast three-hybrid screen is utilized to provide insight into the higher-order complex formation capacity of the Arabidopsis MADS box family. SEPALLATA3 (SEP3) has been shown to mediate complex formation and, therefore, special attention is paid to this factor in this study. 相似文献27.
JF Yuan SJ Zhang O Jafer RA Furlong OE Chausiaux CA Sargent GH Zhang NA Affara 《BMC microbiology》2009,9(1):246
Background
Pseudorabies virus (PRV) is an alphaherpesviruses whose native host is pig. PRV infection mainly causes signs of central nervous system disorder in young pigs, and respiratory system diseases in the adult. 相似文献28.
Jamie Lovaglio James E Artwohl Christopher J Ward Thomas GH Diekwisch Yoshihiro Ito Jeffrey D Fortman 《Comparative medicine》2014,64(2):115-120
Three mice (2 male, 1 female; age, 5 to 16 mo) from a mouse line transgenic for keratin 14 (K14)-driven LacZ expression and on an outbred Crl:CD1(ICR) background, were identified as having distended abdomens and livers that were diffusely enlarged by numerous cysts (diameter, 0.1 to 2.0 cm). Histopathology revealed hepatic cysts lined by biliary type epithelium and mild chronic inflammation, and confirmed the absence of parasites. Among 21 related mice, 5 additional affected mice were identified via laparotomy. Breeding of these 5 mice (after 5 mo of age) did not result in any offspring; the K14 mice with polycystic livers failed to reproduce. Affected male mice had degenerative testicular lesions, and their sperm was immotile. Nonpolycystic K14 control male mice bred well, had no testicular lesions, and had appropriate sperm motility. Genetic analysis did not identify an association of this phenotype with the transgene or insertion site.Abbreviations: K14, keratin 14 promoter; LacZ, bacterial β-galactosidase LacZ reporter; Lsamp, mouse limbic system-associated membrane proteinPolycystic disease is a multiorgan disorder and is the most common genetic life-threatening disease in people, affecting more than 600,000 Americans.16 Cystic liver disease in people typically is associated with polycystic kidney disease22,36 but can exist in its absence. Currently, 2 autosomal dominant genes (PRKCSH and SEC63P) that cause a human polycystic liver disease condition without renal involvement have been identified.4-6,13Numerous rodent models of polycystic kidneys with concurrent polycystic liver exist.8,34,39,40 However, effective models of polycystic liver without polycystic kidneys would be useful to address clinical and mechanistic issues of polycystic liver not associated with polycystic kidneys.6,31Here we report multiple cases of a spontaneous polycystic liver phenotype without a kidney phenotype in a transgenic mouse line. We also describe the effect of the transgene on disease expression and our attempts to develop this stock as an animal model. 相似文献
29.
Hydraulic redistribution affects modeled carbon cycling via soil microbial activity and suppressed fire 下载免费PDF全文
Congsheng Fu Guiling Wang Kenneth Bible Michael L. Goulden Scott R. Saleska Russell L. Scott Zoe G. Cardon 《Global Change Biology》2018,24(8):3472-3485
Hydraulic redistribution (HR) of water from moist to drier soils, through plant roots, occurs world‐wide in seasonally dry ecosystems. Although the influence of HR on landscape hydrology and plant water use has been amply demonstrated, HR's effects on microbe‐controlled processes sensitive to soil moisture, including carbon and nutrient cycling at ecosystem scales, remain difficult to observe in the field and have not been integrated into a predictive framework. We incorporated a representation of HR into the Community Land Model (CLM4.5) and found the new model improved predictions of water, energy, and system‐scale carbon fluxes observed by eddy covariance at four seasonally dry yet ecologically diverse temperate and tropical AmeriFlux sites. Modeled plant productivity and microbial activities were differentially stimulated by upward HR, resulting at times in increased plant demand outstripping increased nutrient supply. Modeled plant productivity and microbial activities were diminished by downward HR. Overall, inclusion of HR tended to increase modeled annual ecosystem uptake of CO2 (or reduce annual CO2 release to the atmosphere). Moreover, engagement of CLM4.5′s ground‐truthed fire module indicated that though HR increased modeled fuel load at all four sites, upward HR also moistened surface soil and hydrated vegetation sufficiently to limit the modeled spread of dry season fire and concomitant very large CO2 emissions to the atmosphere. Historically, fire has been a dominant ecological force in many seasonally dry ecosystems, and intensification of soil drought and altered precipitation regimes are expected for seasonally dry ecosystems in the future. HR may play an increasingly important role mitigating development of extreme soil water potential gradients and associated limitations on plant and soil microbial activities, and may inhibit the spread of fire in seasonally dry ecosystems. 相似文献
30.
Structural analysis of the carbohydrate chains of beta-N-acetylhexosaminidases from bovine brain. 下载免费PDF全文
B Overdijk E P Beem G J van Steijn L A Trippelvitz J J Lisman J Paz Parente P Cardon Y Leroy B Fournet H van Halbeek et al. 《The Biochemical journal》1985,232(3):637-641
The oligosaccharide structures of bovine brain beta-N-acetylhexosaminidases A and B (EC 3.2.1.30) were studied at the glycopeptide level by employing 500 MHz 1H-n.m.r. spectroscopy and methylation analysis involving g.l.c.-m.s. More than 90% of the chains were found to be of the oligomannoside type, containing, on average, five to six mannose residues. Biantennary N-acetyl-lactosamine-type chains terminated in N-acetylneuraminic acid were found to comprise the remaining 5-10% of the total carbohydrate. The isoenzyme forms A and B do not differ from each other in the structure of their carbohydrate moiety, but do deviate in carbohydrate content and, in consequence, in the number of carbohydrate chains per molecule. 相似文献