共查询到20条相似文献,搜索用时 15 毫秒
1.
A Gold 《Science (New York, N.Y.)》1973,181(96):275-276
A wide variety of data on the energy expended by animals in running, flying, or swimming can be accounted for by the simple hypothesis that all animals require the same quantity of energy to carry a unit of their own body mass one "step." For running locomotion this is approximately 3 x 10(-4) calorie per gram per step. 相似文献
2.
3.
4.
从公共财政支出视角来看,制约农民收入增长的因素主要有:(1)落后的基础教育,制约了农民智力素质的提升;(2)落后的交通环境和市场交易环境袁使农村发展面临较高的成本;(3)水利设施严重不足,降低了民族地区农村抵御自然灾害的能力,使农业生产面临较大风险。从理论上来看,公共财政支出对农民收入的影响是通过两大途径发挥作用的:(1)通过社会支出提高农民的健康水平和知识水平,从而增加农民的人力资本积累,增强农民的自我发展能力,提升农民获得更多收入的机会和能力,而且社会支出还通过再分配途径为那些收入特别低下的农民提升社会保障;(2)通过投资于农业、农村基础设施和农业科技,从而促进农业经济增长。利用我国1978-2009年有关统计资料进行实证分析,结果表明,公共财政支出对农业增收有较大影响。因此,促进农民增收、缩小城乡差异的一个重要途径就是加大对农业的财政支持。 相似文献
5.
6.
Regulation of food intake and obesity 总被引:7,自引:0,他引:7
This is not the place to consider the medical significance of obesity in terms of conditions such as heart disease and hypertension, diabetes, and arthritis. These very complex interrelationships have been dealt with elsewhere (69). We hope that enough evidence has been presented to demonstrate that energy balance is normally maintained by a precise and reliable physiologic mechanism, and that the energy surplus represented by obesity may reflect direct failure of this mechanism or some combination from a variety of neurological, endocrine, enzymatic, and psychological disorders. Environmental conditions as well as genetic and traumatic factors may contribute to the development of obesity. If increasing mechanization brings tus below the level of energy expenditure at which food intake is properly regulated, appropriate habits of exercise will have to be established and maintained. 相似文献
7.
8.
9.
10.
R C Collins F Plum F Posner A P Sanders R S Kramer B Woodhall W D Currie 《Science (New York, N.Y.)》1970,170(965):1430-1431
11.
12.
The geographic and temporal variability of freshwater supply in the United States constrains the choice and level of use of future energy sources. Ecological criteria for acceptable freshwater consumption, together with hydrological data on stream flow, provide a framework for estimating these constraints. The water consumption requirements for a variety of energy options are presented, and comparative judgments drawn. Attention is focused on problems resulting from synthetic, gaseous, and liquid fuel production. Scenarios describing possible future levels of coal and electricity use are analyzed. They point to the importance of water supply constraints in both the eastern and western United States. 相似文献
13.
14.
15.
16.
Ferber D 《Science (New York, N.Y.)》1999,283(5407):1423, 1425
17.
18.
19.
Uno K Katagiri H Yamada T Ishigaki Y Ogihara T Imai J Hasegawa Y Gao J Kaneko K Iwasaki H Ishihara H Sasano H Inukai K Mizuguchi H Asano T Shiota M Nakazato M Oka Y 《Science (New York, N.Y.)》2006,312(5780):1656-1659
Coordinated control of energy metabolism and glucose homeostasis requires communication between organs and tissues. We identified a neuronal pathway that participates in the cross talk between the liver and adipose tissue. By studying a mouse model, we showed that adenovirus-mediated expression of peroxisome proliferator-activated receptor (PPAR)-g2 in the liver induces acute hepatic steatosis while markedly decreasing peripheral adiposity. These changes were accompanied by increased energy expenditure and improved systemic insulin sensitivity. Hepatic vagotomy and selective afferent blockage of the hepatic vagus revealed that the effects on peripheral tissues involve the afferent vagal nerve. Furthermore, an antidiabetic thiazolidinedione, a PPARg agonist, enhanced this pathway. This neuronal pathway from the liver may function to protect against metabolic perturbation induced by excessive energy storage. 相似文献
20.
Diabetes, obesity, and the brain 总被引:1,自引:0,他引:1
Recent evidence suggests a key role for the brain in the control of both body fat content and glucose metabolism. Neuronal systems that regulate energy intake, energy expenditure, and endogenous glucose production sense and respond to input from hormonal and nutrient-related signals that convey information regarding both body energy stores and current energy availability. In response to this input, adaptive changes occur that promote energy homeostasis and the maintenance of blood glucose levels in the normal range. Defects in this control system are implicated in the link between obesity and type 2 diabetes. 相似文献