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The regulation of food intake is a complex mechanism, and the hypothalamus is the main central structure implicated. In particular, the arcuate nucleus appears to be the most critical area in the integration of multiple peripheral signals.Among these signals, those originating from the white adipose tissue and the gastrointestinal tract are known to be involved in the regulation of food intake.The present paper focuses on adiponectin, an adipokine secreted by white adipose tissue, which is reported to have a role in the control of feeding by acting centrally. The recent observation that adiponectin is also able to influence gastric motility raises the question of whether this action represents an additional peripheral mechanism that concurs with the central effects of the hormone on food intake. This possibility, which represents an emerging aspect correlating the central and peripheral effects of adiponectin in the hunger-satiety cycle, is discussed in the present paper.  相似文献   
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BackgroundLittle is known about breakfast habits of the Latin American (LA) population to support nutritional recommendations for a balanced breakfast in this region.ObjectiveTo evaluate the nutritional composition of breakfast in the LA population and to propose recommendations for a balanced breakfast.DesignThis multicenter cross-sectional study evaluated food and nutrient intake of nationally representative samples of urban populations of 8 LA countries (Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Peru, and Venezuela) in 2014-2015.Participants/settingThe sample comprised 8714 participants from the Latin American Study of Nutrition and Health, aged 15 to 65 years, randomly recruited according to geographical location, sex, age, and socioeconomic level.Main outcome measuresTwo 24-hour recalls were used to examine dietary intake. Breakfast consumers were stratified by tertiles of Nutrient-Rich Foods Index 9.3 (NRF9.3) to assess the overall diet quality of individuals. Nutrient intake at breakfast of those in the upper tertile of NRF9.3 pooled for the 8 countries was used as a reference for the development of recommendations for LA adolescents and adults.Statistical analysesComparison of food and nutrient intake of breakfast across NRF9.3 tertiles were analyzed using the Kruskal-Wallis rank sum test.ResultsOverall breakfast was an important contributor to protein, carbohydrate, and B vitamin intakes but also to added sugar and total and saturated fat intakes relative to daily intakes. Individuals in the upper NRF9.3 tertile had higher intake of key micronutrients such as calcium and potassium at breakfast compared with other tertiles. White breads/rolls/tortillas were the most consumed food group (60%), followed by butter/margarine (40%) and coffee/tea without milk (34%-50%).ConclusionsBreakfast contributed to the daily intake of B vitamins, protein, and carbohydrates but also added sugar and total and saturated fat intakes for all countries. The proposed recommendations support the nutrient density of existing highest-quality breakfast in the LA population while addressing concerns about nutrients to be encouraged or reduced.  相似文献   
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选用菜心作为富硒的研究对象,采用不同质量浓度的亚硒酸钠进行喷施处理,测定总硒和有机硒的含量以及不同的富硒浓度对菜心植株产量和各营养成分的影响。结果显示:喷施低浓度硒可以增进菜心品质而高浓度硒则抑制了菜心植株的正常生长和生理代谢。在富硒菜心中,75%以上的硒以有机硒的形式存在,体内的无机硒主要以6价硒存在,6价硒占总无机硒的94%以上;硒可以明显的提高菜心叶绿素、蛋白质、维生素C和氨基酸的含量,但可溶糖的含量降低。  相似文献   
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Twenty-eight members of the general public, with little nutritional knowledge and no previous commitment to dietary change, completed 7-day-weighed dietary diaries. They then attempted to change their diets, where appropriate, in line with current nutritional guidelines.
The panel achieved changes in diet that were consistent with the recent recommendations but several problems arose. In particular, although fat levels were reduced, energy levels fell and fibre goals were not reached; in addition, certain of the initial vitamin and mineral intakes gave cause for concern. These results emphasize the importance of giving advice not only about foods that might be reduced in the diet, but also about food that might be used as alternatives. They also illustrate the difficulty of persuading people to make radical changes to their eating habits even when given personal advice from a nutritionist.
The panel was small and not necessarily representative, but the results illustrate the need for more dietary analysis studies. It is not enough simply to formulate appropriate guidelines from a nutritional point of view; it is also important to ensure that the public understands them and that people make sensible decisions about their diet.  相似文献   
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植物营养活力素对小鼠生长及耐受能力的影响   总被引:3,自引:3,他引:0  
以不同剂量的植物营养活力素(PVN)喂饲小鼠,对小鼠的体重增长、耐寒、耐热、耐力等进行了观测。结果:用药后实验小鼠的体重和胸脾系数明显增加;耐寒、耐热及持续游泳时间明显延长。表明PVN可明显提高小鼠的体重增长和对应激的耐受能力,提示其营养作用不仅适用于植物,而且适用于动物。  相似文献   
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张格祥  王玉  苏莉 《现代预防医学》2005,32(6):593-594,597
目的:观察锌(Zn)、维生素A(VA)、维生素B2(VB2)缺乏和补充对初断乳大鼠进食量、体重的影响。方法:通过耗竭一补充方式造成初断乳大鼠的Zn、VA、VB2单独和联合缺乏模型,后强化补充相应营养素,动态检测大鼠进食量、体重的变化。结果:Zn、VA、VB2缺乏时不同程度地影响大鼠进食量、体重,以联合缺乏影响最为突出;强化补充相应营养素后,大鼠进食量、体重均得到改善,但仍达不到正常发育水平。结论:婴幼期Zn、VA、VB2缺乏或不足可影响生长发育,应充分重视婴幼儿营养。  相似文献   
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