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951.
Geoffrey G. Wilson Rachael L. Neve Gordon J. Edlin William H. Konigsberg 《Genetics》1979,93(2):285-296
Bacteriophage T4 cytosine-containing DNA is cleaved at a single site by the restriction endonuclease, Bam H1. The site lies within the late region of the T4 genome, close to, or within, gene 8, one of the structural genes of the phage particle baseplate. 相似文献
952.
Shanghong Xie Xiang Li Peter McColgan Rachael I. Scahill Donglin Zeng Yuanjia Wang 《Biometrics》2020,76(3):995-1006
Biomarkers are often organized into networks, in which the strengths of network connections vary across subjects depending on subject-specific covariates (eg, genetic variants). Variation of network connections, as subject-specific feature variables, has been found to predict disease clinical outcome. In this work, we develop a two-stage method to estimate biomarker networks that account for heterogeneity among subjects and evaluate network's association with disease clinical outcome. In the first stage, we propose a conditional Gaussian graphical model with mean and precision matrix depending on covariates to obtain covariate-dependent networks with connection strengths varying across subjects while assuming homogeneous network structure. In the second stage, we evaluate clinical utility of network measures (connection strengths) estimated from the first stage. The second-stage analysis provides the relative predictive power of between-region network measures on clinical impairment in the context of regional biomarkers and existing disease risk factors. We assess the performance of proposed method by extensive simulation studies and application to a Huntington's disease (HD) study to investigate the effect of HD causal gene on the rate of change in motor symptom through affecting brain subcortical and cortical gray matter atrophy connections. We show that cortical network connections and subcortical volumes, but not subcortical connections are identified to be predictive of clinical motor function deterioration. We validate these findings in an independent HD study. Lastly, highly similar patterns seen in the gray matter connections and a previous white matter connectivity study suggest a shared biological mechanism for HD and support the hypothesis that white matter loss is a direct result of neuronal loss as opposed to the loss of myelin or dysmyelination. 相似文献
953.
Kirsten A. McAuley Rachael W. Taylor Victoria L. Farmer Paul Hansen Sheila M. Williams Chris S. Booker Jim I. Mann 《Obesity (Silver Spring, Md.)》2010,18(1):131-136
Effective strategies are urgently required to reduce the prevalence of obesity during growth. Determining which strategies are most successful should also include analysis of their relative costs. To date, few obesity prevention studies in children have reported data concerning cost‐effectiveness. The aim of this study was to assess the costs and health benefits of implementing the APPLE (A Pilot Program for Lifestyle and Exercise) project, a 2‐year controlled community‐based obesity prevention initiative utilizing activity coordinators (ACs) in schools and nutrition promotion in New Zealand children (5–12 years). The marginal costs of the project in 2006 prices were estimated and compared with the kilograms (kg) of weight‐gain prevented for children in the intervention relative to the control arm. The children's health‐related quality of life (HRQoL) was also measured using the Health Utilities Index (HUI). The total project cost was NZ$357,490, or NZ$1,281 per intervention child for 2 years (NZ$1 = US$0.67 = UK£0.35 = EUR €0.52). Weight z‐score was reduced by 0.18 (0.13, 0.22) units at 2 years and 0.17 (0.11, 0.23) units at 4 years in intervention relative to control children. Mean HUI values did not differ between intervention and control participants. The reduction in weight z‐score observed is equivalent to 2.0 kg of weight‐gain prevented at 15 years of age. The relatively simple intervention approach employed by the APPLE project was successful in significantly reducing the rate of excessive weight gain in children, with implementation costs of NZ$664–1,708 per kg of weight‐gain prevented over 4 years. 相似文献
954.
Zisca R. Dixon Betty J. Burri Andrew Clifford Edwin N. Frankel Barbara O. Schneeman Elizabeth Parks Nancy L. Keim Teresa Barbieri Mei-Miau Wu Alice K.H. Fong Mary J. Kretsch Anne L. Sowell John W. Erdman Jr. 《Free radical biology & medicine》1994,17(6):537-544
The effect of consuming a low carotene diet (≈60 μg carotene/day) on oxidative susceptibility and superoxide dismutase (SOD) activity in women living in a metabolic research unit was evaluated. The diet had sufficient vitamins A, E, and C. The women ate the diet supplemented with 1500 μg/day β-carotene for 4 days (baseline), then the unsupplemented diet for 68 days (depletion), followed by the diet supplemented with > 15,000 μg/day carotene for 28 days (repletion). Production of hexanal, pentanal, and pentane by copper-oxidased plasma low density lipoproteins from carotene-depleted women was greater than their production of these compounds when repleted with carotene. Erythrocyte SOD activity was depressed in carotene-depleted women; it recovered with repletion. Thiobarbituric acid reactive substances in plasma of carotene-depleted women were elevated and diminished with repletion. Dietary carotene seems to be needed, not only as a precursor of vitamin A, but also to inhibit oxidative damage and decrease oxidation susceptibility. 相似文献
955.
Singh Anamika Duche Rachael Terumbur Wandhare Arundhati Ganesh Sian Jaspreet Kaur Singh Brij Pal Sihag Manvesh Kumar Singh Kumar Siddharth Sangwan Vikas Talan Shreya Panwar Harsh 《Probiotics and antimicrobial proteins》2023,15(1):44-62
Probiotics and Antimicrobial Proteins - The growing consumer awareness towards healthy and safe food has reformed food processing strategies. Nowadays, food processors are aiming at natural,... 相似文献