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81.
Between 1811 and 2003, the mean height of 17-year-old Estonian boys increased 18.4 cm (0.97 cm per decade). The increase was 5.2 cm (0.7 cm per decade) between 1811 and 1886, 12.3 cm (2.2 cm per decade) between 1922 and 1978, and 0.5 cm per decade between 1978 and 2003. Between 1922 and 2003, mean height increased 8.2% and mean weight increased 27.2%. Between 1956 and 2003, biacromial (shoulder) breadth increased more than bicristal (hip) breadth; relative chest depth diminished; chest circumference and upper thigh circumference both increased. A multidimensional body structure model is constructed from 1998 to 2003 data.  相似文献   
82.
A total of 39 postmenopausal women 40–70 years of age and undergoing hormone replacement therapy participated in a 6-month weight reduction program, which consisted of a low calorie diet (5040 KJ/day) and phentermine hydrochloride therapy. Subjects had an average body mass index of 35.95±5.32 kg/m2 and 42.20±11.0 kg of total fat. Body mass index, plasma lipids, total and trunk fat, and plasma apoproteins were measured at baseline and after 3 and 6 months of the weight reduction program. Subjects experienced an overall 10% weight loss during the treatment period (P<0.001). Plasma LDL cholesterol and triglycerides were reduced by 18% and 15% (P<0.01) respectively, whereas HDL cholesterol was increased by 9% (P<0.01) over the 6-month period. Plasma apoproteins were significantly affected by weight loss. Plasma apolipoprotein (apo) B concentrations were reduced 6.5% (P<0.01), and apo C-III and apo E were reduced by 9% over 6 months (P<0.01). The observed decreases in plasma apo B were significantly correlated with the observed changes in plasma cholesterol (r=0.356, P<0.01) over 3 months. In addition, changes in plasma triglycerides were correlated with changes in both apo C-III (r=0.436) and apo E (r=0.354) over 6 months. These results suggest that weight loss may have multifactorial effects on lipoprotein metabolism, resulting in better plasma lipid and apoprotein profiles.  相似文献   
83.
中国学生体质发育的生长加速及与日本学生的比较   总被引:3,自引:1,他引:2  
陈德珍 《人类学学报》2000,19(4):284-297
在 1 98 5年和 1 995年国家教委、国家体委、卫生部、国家民委、国家科委共同领导和组织的全国性的学生体质健康调查基础上 ,及本世纪 30年代起个别省城 (北京市、天津市、上海市、丹阳市 (县 )、南京市、辽宁省、黑龙江省及山东省 )学生的体质调查资料基础上 ,作者经数理统计 ,并就我国学生的体质发育状况和生长加速问题对汉族学生和少数民族学生分别加以分析讨论 ,从而了解了我国学生体质发育的现状 ;经与近邻的日本国的学生的体质发育和生长加速状况比较后也找到了差距。
我国学生的体质发育水平目前虽有些不足 ,但我国学生的体质发育指标的生长增长值比日本国学生在身高指标上 ,男学生大2.10cm,女学生大1.65cm;在体重指标上 ,男学生大2.22kg,女学生大1.54kg,身高和体重指标相对日本国而言都仍呈较大的增长趋势 ,存在发展潜力 ,我国学生的体质定将有提高的可能。但胸围指标与身高和体重指标相比 ,除城市男女学生增长值还较大外 ,乡村学生的增长值却为偏低 ,这将影响我国学生的身体素质 ,影响整体生长发育水平的提高。这些将为我国有关部门制定方针政策和实施措施提供可靠的科学依据。我国的经济正在迅速发展 ,对我国学生的营养已采取了积极的措施加以改善和提高 ,并加强了学生的体育锻炼,中小学学生的学业负担也正在减轻,因此,对我国学生体质发育的促进的效果是可能达到的。  相似文献   
84.
饲喂重组鸡白细胞介素18蛋白增加肉仔鸡体重的初步研究   总被引:4,自引:0,他引:4  
经口服途径给肉仔鸡饲喂重组鸡白细胞介素 1 8(ChIL -1 8)蛋白,观察其在正常饲养条件下和人工感染鸡传染性支气管炎病毒 (IBV)时对肉仔鸡的影响。将 84只肉仔鸡随机分为 2组:正常称重组和IBV接种组。 2组肉仔鸡再随机各分为 3个亚组,分别每隔 5d各口服 1次PBS、细菌蛋白和重组ChIL -1 8蛋白。正常称重组每亚组 8只,每次口服前称重。IBV接种试验组每亚组 2 0只,在 30日龄时滴鼻接种IBVM41株并每隔 5d称重 1次。各亚组试验鸡分别在正压隔离器中饲养。结果表明,饲喂重组ChIL- 1 8蛋白的试验亚组肉仔鸡体重总增重量明显高于饲喂PBS和细菌蛋白的对照亚组;IBV接种试验组肉仔鸡在人工感染IBVM41株后,饲喂重组ChIL 1 8亚组的发病率和死亡率明显低于饲喂PBS和细菌蛋白亚组,而且后 2个亚组肉仔鸡临床症状也较饲喂重组ChIL- 1 8试验亚组明显。结果初步显示,饲喂重组ChIL -1 8融合蛋白能够增加肉仔鸡体重并可增强肉仔鸡对IBV感染的抵抗能力。  相似文献   
85.
86.
The body size of adult Cook Islanders on Rarotonga for the years 1952, 1966 and 1996 has been increasing. The rate of increase in stature of women aged 20-39 years was 0.5cm per decade across the period 1952-1966, and 0.8cm per decade for the period 1966-1996. The rate of increase of weight in the 20-29 years age group was 0.6kg per decade in period 1, and 7.3kg per decade in period 2. In the age group 30-39 years, the rates were 3.2kg per decade and 5.1kg per decade respectively. Changing food availability for the period 1961-2000 is used to compare estimates of dietary energy availability with estimates of physiological energy requirements. There has been reduced availability of traditional staples, a likely reduction in consumption of fish, increased consumption of meat, and a decline in the availability of dietary fats and oils. Daily per capita energy intakes in 1952 and 1966 greatly exceed an hypothetical physiological maximum value for energy expenditure, suggesting a large positive energy balance in 1952 and an even greater one in 1966, both predisposing to weight gain. Although daily per capita energy availability in 1996 is similar to the hypothetical physiological maximum value for energy expenditure, it exceeds the measured level of energy expenditure at that time. It is speculated that excessive energy intake relative to requirement is more likely to predispose to positive energy balance and weight gain than decline in energy expenditure, although to a lower extent than in 1966 and 1952.  相似文献   
87.
Craig  David M. 《Population Ecology》1986,28(2):173-183
Population Ecology - The present research has not identified all of the factors that interact to produce the observed egg cannibalism rates inTribolium. It has, however, shown that some physical...  相似文献   
88.
Resource exploitation by and intraspecific competition in larvae of Gastrophysa atrocyanea and Galerucella vittaticollis were investigated in field and laboratory experiments. Larvae of both species frequently suffered from food shortages in the field. When G. atrocyanea larvae suffered from a food shortage, severe intraspecific competition occurred because of lack of predation and parasitism. This exploitive competition was caused by a local food shortage of the host plant. Individuals survived by fast exploitation when food became abundant (contest type competition). the G. atrocyanea larvae were wasteful of the food resource, and no mechanism by which to economize on the utilization of the resource was acquired because of their exploitation of the abundant resource. In contrast, the G. vittaticollis population probably is regulated by extrinsic factors such as predation and parasitism. Those larvae grew into smaller adults than those of G. atrocyanea under a food shortage, so that their wasted food consumption was lower than that of G. atrocyanea. Although intraspecific competition was similar to that for G. atrocyanea, it was not as severe. The food for G. vittaticollis was apt to be appropriated by other wasteful exploitators such as G. atrocyanea, which was superior in resource exploitation; therefore G. vittaticollis frequently suffered a food shortage. Consequently selection in relation to tolerance to starvation became more acute for G. vittaticollis than for G. atrocyanea, and individuals of G. vittaticollis that could endure starvation better may have been selected.  相似文献   
89.
Malnutrition is associated with an inadequate diet, poor health and sanitation services and inadequate care for young children. A combination of income growth and nutrition interventions are therefore suggested to adequately tackle this issue [Haddad, L., Alderman, H., Appleton, S., Song, L., Yohannes, Y., 2003. Reducing child malnutrition: how far does income growth take us? World Bank Econ. Rev., 17, 107-131.], yet evidence to support this claim is often not available, especially for African settings. This paper evaluates the joint contribution of income growth and nutrition interventions towards the reduction of malnutrition. Using a four round panel data set from northwestern Tanzania we estimate the determinants of a child's nutritional status, including household income and the presence of nutrition interventions in the community. The results show that better nutrition is associated with higher income, and that nutrition interventions have a substantial beneficial effect. Policy simulations make clear that if one intends to halve malnutrition rates by 2015 (the MDG objective), income growth will have to be complemented by large scale program interventions.  相似文献   
90.
This study utilizes a natural experiment—conditionally random dormitory assignments of first-year US college students—to investigate the influence of obesogenic environmental factors in explaining changes in weight and exercise behavior during the 2009–2010 academic year. The design addresses potential selection biases resulting from the likelihood that individuals sort into built environments that match their preferences for exercise and healthy eating. We find some evidence that the food environment, specifically access to campus dining, significantly affected the weight of female students in our study. Females assigned to dormitories where the nearest campus dining hall was closed on the weekends gained about 1 lb less over the course of the year than females assigned to dormitories near dining halls that were open 7 days a week. We also find some evidence that female who lived in close proximity to a grocery store gained less weight over the course of the year. Finally, females who lived closer to campus gym reported more frequent exercise over the course of the year. We do not find significant effects of the built environment on weight changes of males in our sample, but we are cautious to draw strong conclusions from this because the male weight change in our sample was quite small.  相似文献   
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