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Tweedia caerulea flowers are sensitive to ethylene and the closing of the flowers, a characteristic of senescence, is accelerated by exposure to ethylene. T. caerulea flowers were continuously treated with ethanol at concentrations of 0, 2, 4, 6, 8, 10 or 12 %, and treatment levels at 4 % and above showed delayed closing. Ethanol accelerated climacteric increase in ethylene production from flowers. Although ethylene production was higher in gynoecium than in petals, ethanol treatment accelerated ethylene production by both organs. Exposure to ethylene increased autocatalytic ethylene production, and production was further accelerated by ethanol treatment. When flowers treated with ethanol were exposed to ethylene, senescence was delayed compared to that for untreated flowers, suggesting that ethanol reduces the sensitivity of flowers to ethylene. These results indicate that treatment with ethanol delays petal senescence in cut T. caerulea flowers, possibly through reduced sensitivity to ethylene.  相似文献   
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Myostatin (MSTN), a member of transforming growth factor-β (TGF-β) superfamily, is a negative regulator of the skeletal muscle growth, and suppresses the proliferation and differentiation of myoblast cells. Dysfunction of MSTN gene either by natural mutation or genetic manipulation (knockout or knockdown) has been reported to interrupt its proper function and to increase the muscle mass in many mammalian species. RNA interference (RNAi) mediated by small interfering RNAs (siRNAs) or short hairpin RNAs (shRNAs) has become a powerful tool for gene knockdown studies. In the present study transient silencing of MSTN gene in chicken embryo fibroblast cells was evaluated using five different shRNA expression constructs. We report here up to 68% silencing of myostatin mRNA using these shRNA constructs in transiently transfected fibroblasts (p<0.05). This was, however, associated with induction of interferon responsive genes (OAS1, IFN-β) (3.7-64 folds; p<0.05). Further work on stable expression of antimyostatin shRNA with minimum interferon induction will be of immense value to increase the muscle mass in the transgenic animals.  相似文献   
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Objective: This study compared the relationship between fair/poor general health status among overweight and obese Polynesians with that among other overweight and obese persons in Hawaii. Methods and Procedures: Data were pooled from the 1998–2003 Hawaii Behavioral Risk Factor Surveillance System (BRFSS) and logistic regression used to examine the predictors of fair/poor health status. Results: Polynesians were significantly more likely to be obese than non‐Polynesians; overweight Polynesians were more likely than other overweight individuals to report fair/poor health status. After adjusting for confounders, among Polynesians, being obese was no longer associated with fair/poor health. Non‐Polynesians who were obese (odds ratio 1.9; 95% confidence interval: 1.4–2.6), older, less educated, smokers, diabetic, hypertensive, and physically inactive were more likely to report fair/poor health. Discussion: Although Polynesians were significantly more obese than the rest of the Hawaii population, their weight was not independently associated with their odds for fair/poor health as it was with non‐Polynesians. The difference may be that, for Polynesians, hypertension and diabetes overrode the effect of obesity on general health status or this group maintains different cultural perceptions of body size. Regardless, these findings show a major health risk among Polynesians and suggest the need for culturally specific health interventions.  相似文献   
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The complex microbiome of the rumen functions as an effective system for the conversion of plant cell wall biomass to microbial proteins, short chain fatty acids and gases. In this study, metagenomic approaches were used to study the microbial populations and metabolic potential of the microbial community. DNA was extracted from Surti Buffalo rumen samples (four treatments diet) and sequenced separately using a 454 GS FLX Titanium system. We used comparative metagenomics to examine metabolic potential and phylogenetic composition from pyrosequence data generated in four samples, considering phylogenetic composition and metabolic potentials in the rumen may remarkably be different with respect to nutrient utilization. Assignment of metagenomic sequences to SEED categories of the Metagenome Rapid Annotation using Subsystem Technology (MG-RAST) server revealed a genetic profile characteristic of fermentation of carbohydrates in a high roughage diet. The distribution of phylotypes and environmental gene tags (EGTs) detected within each rumen sample were dominated by Bacteroidetes/Chlorobi, Firmicutes and Proteobacteria in all the samples. The results of this study could help to determine the role of rumen microbes and their enzymes in plant polysaccharide breakdown is fundamental to understanding digestion and maximising productivity in ruminant animals.  相似文献   
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Objective: We examined the associations among physical activity, sedentary behavior, and metabolic syndrome in a representative sample of U.S. adults. Research Methods and Procedures: A total of 1626 men and women ≥20 years old from National Health and Nutrition Examination Survey 1999 to 2000 who attended the morning examination were evaluated. The metabolic syndrome was defined by using the definition from the National Cholesterol Education Program. Results: In unadjusted analysis, participants who did not engage in any moderate or vigorous physical activity during leisure time had almost twice the odds of having metabolic syndrome [odds ratio (OR), 1.90; 95% confidence interval (CI), 1.22 to 2.97] as those who reportedly engaged in ≥150 min/wk of such activity. Adjustment for age, sex, race or ethnicity, educational status, smoking status, and alcohol use attenuated the OR (OR, 1.46; 95% CI, 0.87 to 2.45). Compared with participants who watched television or videos or used a computer <1 h/d outside of work, the adjusted ORs for having metabolic syndrome were 1.41 (95% CI 0.80 to 2.51) for 1 h/d, 1.37 (95% CI 0.85 to 2.20) for 2 h/d, 1.70 (95% CI 0.92 to 3.14) for 3 h/d, and 2.10 (95% CI 1.27 to 3.47) for ≥4 h/d. Additional adjustment for physical activity or sedentary behavior minimally affected the ORs. Discussion: Sedentary behavior is an important potential determinant of the prevalence of the syndrome. Efforts to lessen the amount of time that U.S. adults spend watching television or videos or using a computer, especially if coupled to increases in physical activity, could result in substantial decreases in the prevalence of metabolic syndrome.  相似文献   
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Human Ecology - Seasonal rounds are deliberative articulations of a community’s sociocultural relations with their ecological system. The process of visualizing seasonal rounds informs...  相似文献   
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The regression methods with dummy variables have been shown to be effective in preventing confusion in the analysis of linear models. In particular, this model simplifies interpretation of parameters and clarifies hypothesis statements. All existing methods have been shown as special cases of the general linear hypothesis in regression setting. Three regression on dummy variables methods are examined critically to bring out the salient features of each method. The choice of a method should be based on the way definitions of the parameters are desired. The linear models are considered in a regression model setting. This has been done by defining appropriate dummy variables in a regression model which often is desirable, if not mandatory, when dealing with unbalanced data involving two or more factors.  相似文献   
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