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271.
Journal of Crop Science and Biotechnology - Breeding for drought tolerance and increased grain yield is vital in mitigating the threat posed by recurrent drought stress on maize production, as well...  相似文献   
272.
OBJECTIVE: Among adults with diabetes attempting to change their own diets, we explored how these adults approached providing food for their children and how their children reacted to dietary changes in the household. DESIGN: The research design used semi-structured parallel individual interviews of adults and a child (aged 10-17 years) in their home. Interviews were audio-taped, transcribed, coded and analysed for themes. SUBJECTS: Subjects included families in which one inner-city African American or Latino adult with diabetes had completed a diabetes intervention promoting healthy dietary behaviours. RESULTS: We completed 29 interviews (14 adult-child pairs and one child). Adults approached making dietary changes for themselves and also providing food for their family in different ways, ranging from expecting everyone to eat the same thing to preparing two separate meals. Many children resisted dietary changes while fewer acquiesced. Among children who went along with changes, some reported resisting initially then adjusting, while others did not resist because the food still tasted good or they could obtain preferred foods outside the house. The intersection of adults' meal strategies and children's reactions to the changes can be used to categorise families into different patterns. These patterns highlight the tension between an adult who must make dietary changes to control diabetes and a child who is not necessarily motivated to change. CONCLUSION: From this framework we suggest hypotheses about how these patterns might influence dietary behaviour in adults and children. Understanding these patterns could guide interventions to assist parents in successfully including children in their dietary changes.  相似文献   
273.
The mechanism of enhanced effect of (-)-epigallocatechin-3-gallate (EGCG) on huperzine A's (HUP) inhibition of acetylcholinesterase (AChE) activity in rats was investigated. The inhibitory effects of HUP at 10 and 5 microg/kg on AChE activity were quite weak in the whole phase. In contrast, upon addition of EGCG (100 mg/kg) to the HUP 10 and 5 microg/kg groups, remarkably enhanced inhibitory effects with maximum inhibitory percentages of 90.94 and 88.13% were observed under the same conditions. EGCG also can greatly prolong the inhibitory time. The mechanism of the enhanced effects of EGCG on HUP's inhibition of AChE activity was investigated by steady fluorescence spectroscopy, infrared spectroscopy, and ultraviolet spectroscopy. HUP hardly interacted with the main transport protein, whereas there was a very strong binding interaction between EGCG and bovine serum albumin. The enhanced transport of HUP is a possible cause of the enhanced effect of EGCG on HUP bioactivity.  相似文献   
274.
The implementation of any sustainable breeding program requires a maximization of effective size (Ne) to maintain inbreeding rate at minimum levels. However, the control of Ne remains a major challenge for those species whose reproduction in captivity is based on a spawning strategy where there is no control over the established matings. The present study aims to assess the spawning dynamic of gilthead sea bream (Sparus aurata) at different dates from two mini‐broodstocks (4 ♀ and 4 ♂). Here we report the use of a simple protocol based on the genotyping of fertilized eggs from a reduced set of microsatellite loci which provides a quick evaluation of daily spawning in terms of family structuring (number of active breeders and number and family size). According to our results, the daily spawning dynamics is characterized by a fluctuation in the number of active breeders, reaching maximum values (until 100%) during peak production phase. However, the proportion of possible mating (families) in a single daily spawning never exceeded more than 81%. Unbalanced parental contributions were highly frequent, with extreme cases involving the assignment of 50%–90% of the offspring to a single family. Therefore, the use of mini‐broodstocks and the grouping of spawning harvested at different dates are proposed as strategies to minimize the inbreeding risk by providing a more optimal pattern of family structuring (increase in the number of families obtained and a more balanced parental contributions) that entails a more conservative Ne/N ratio.  相似文献   
275.
Among the fungi associated with the kiwi wood diseases, the vascular pathogen Phaeoacremonium minimum can infect plants already at nursery stage, without any external symptoms. At the moment, there are not effective control strategies. The effect of soil treatments applicable in organic agriculture was evaluated in two-years experiments on potted kiwi plants artificially inoculated with P. minimum. The soil treatments were based on commercial formulations of iron chelate, silicon, neem paste, Trichoderma afroharzianum strain T22, and cover cropping with selected perennial Poaceae. Cover cropping and iron chelate treatments enhanced the iron availability for the plants and significantly reduced wood necrosis caused by the pathogen. Both treatments also produced an increase of hairy root proliferation, so the plants were able to better cope with stress conditions. Laboratory assays showed the role of iron on the pathogen growth and its pathogenesis enzyme activities.  相似文献   
276.
Enzymes are good tool to modify wheat proteins by creating new bonds between the protein chains. In this study, the effect of the addition of glucose oxidase (GO) and transglutaminase (TG) on the wheat flour proteins is presented. The modification of wheat proteins was determined by analyzing the changes in gluten quality, alveograph parameters, and protein modifications. The amount of wet gluten increased with the addition of GO and TG, but the gluten quality was not improved in any case. Regarding the alveograph parameters, the effect of GO was readily evident obtaining wheat dough with higher tenacity and lower extensibility than the control, while TG led to doughs with lower tenacity and that were also less extensible. The protein modifications were characterized by free‐zone capillary electrophoresis (FZCE). FZCE data indicated that TG polymerizes mainly glutenins and, of those, the high molecular weight glutenin subunits were the most affected.  相似文献   
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