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1.
An experimental model of protein calorie malnutrition (PCM) was created in young rhesus monkeys. Ulnar and tibial nerves from six monkeys with PCM, six rehabilitated and 12 control monkeys were studied for lipid composition and activity of myelin marker enzyme. Total lipids, myelin marker lipids and activity of myelin marker enzyme, 2', 3'-cyclic nucleotide 3' - phosphohydrolase were decreased, while esterified cholesterol and free fatty acids were increased in PCM as compared to controls. There was partial recovery in myelin marker lipids and complete restoration of other lipids on nutritional rehabilitation.  相似文献   

2.
3.
Summary Genetic improvement in growth of poultry has traditionally proceeded via selection for body weight at a fixed age. Due to increased maintenance costs and reproductive problems of adult broiler breeders, the potential for genetic manipulation of the growth curve has been receiving increased interest. Research of both male and female progeny of a three-way diallel cross was used to investigate the inheritance of growth curve parameters. The Laird form of the Gompertz equation was used to determine growth curve parameters, and was suited to the juvenile growth data frequently collected from meat-type chickens. Growth rate exhibited significant heterosis due to both autosomes and the sex chromosomes. Age at inflection point also exhibited significant average heterosis, though only among females. Growth rate was also influenced by average line effects, as was age at inflection point. Maternal effects had no influence on growth curve parameters, while additive sex linkage was observed for growth rate. Phenotypic and genetic correlations were calculated among the growth curve parameters and suggest that specific breeding programs could alter the growth trajectory of the contemporary broiler chicken. Moderate heritabilities were observed for the growth curve parameters and support the hypothesis that the growth curve could be altered via genetic manipulation of early postnatal growth, especially during the first 14 days post-hatch.  相似文献   

4.
Genetic analyses were conducted on 51 anthropometric measurements and on four factors derived from them by factor analysis. These variables were obtained on 784 members of a religious isolate, the S-leut. Correlations were computed between relatives, and heritabilities were estimated using information on extended families. Longitudinal measurements generally exhibited the highest heritabilities. The test for fit of a major gene model was significant for 13 of the 55 variables, the circumferential and breadth measurements giving the strongest evidence for major gene control. In another approach to establishment of genetic control, linkage analysis was performed between the anthropometric variables and blood group and serum protein polymorphisms. Several traits showed some evidence for linkage but none achieved statistical significance.  相似文献   

5.
An anthropometric survey of 750 preschoolers was conducted during 1979 in Belize to assess nutritional status in two districts, one coastal and the other inland. Mothers were interviewed concerning reproductive history, child's health and dietary history, and associated factors. Analysis included the recognition of low arm circumference, weight-for-age, stature-for-age, and weight-for-stature. Survey results indicate that about 25% of the children, birth to 5 years old, show evidence of stunting, while 2.5% show evidence of wasting. Comparisons of rates of malnutrition by ethnic group reveal that the Maya and Garifuna (Black Carib) children are significantly more commonly malnourished than others. Applying a discriminant function to groups of children designated as “poor” and “better-than-average” growth classes reveals several factors which may be contributory to the etiology of preschool malnutrition in Belize. The frequency of diarrhea and age at introduction to solid foods, are significantly related to growth retardation among preschoolers. Analysis of 24-hour-diet recalls corroborates the patterning of malnutrition among ethnic groups.  相似文献   

6.
Morphometric data collected from 118 male and 169 female savannah baboons (Papio cynocephalus anubis) aged between birth and 5.5 years were analyzed to describe the morphology and physical growth of this species. Measurements included weight, crown-rump length, triceps circumference, and skinfolds at the neck, subscapular, suprailiac, and triceps anatomical sites. Principal components analyses were applied to the data to provide multivariate assessments of morphological patterning among the variables. These analyses resulted in the extraction of two unrotated orthogonal components that accounted for 88% of the overall sample variation. The first component accounted for 77% of the variation and represents an axis of overall body size. The second component represents an axis of shape variation that contrasts body size with fat patterning, and was interpreted as a measure of body leanness. Individual component scores were computed for determining age, gender, and age-by-gender interaction effects. Both components were found to be age dependent for both genders. Males and females shared similar age patterning along the two components; however, gender differences did occur in patterning along the two components; however, gender differences did occur in respect to leanness. The multivariate measure of overall body size increased for both genders similarly with advancing age. Age patterning along the leanness component was described as a decrease from birth to 1 year, followed by an increase in leanness in older ages. Females had a delayed and significantly less intense increase in leanness relative to males.  相似文献   

7.
The high oil dependence and the growth of energy use in the transport sector have increased the interest in alternative nonfossil fuels as a measure to mitigate climate change and improve energy security. More ambitious energy and environmental targets and larger use of nonfossil energy in the transport sector increase energy–transport interactions and system effects over sector boundaries. While the stationary energy sector (e.g., electricity and heat generation) and the transport sector earlier to large degree could be considered as separate systems with limited interaction, integrated analysis approaches and assessments of energy–transport interactions now grow in importance. In recent years, the scientific literature has presented an increasing number of global energy–economy future studies based on systems modelling treating the transport sector as an integral part of the overall energy system and/or economy. Many of these studies provide important insights regarding transport biofuels. To clarify similarities and differences in approaches and results, the present work reviews studies on transport biofuels in global energy–economy modelling and investigates what future role comprehensive global energy–economy modelling studies portray for transport biofuels in terms of their potential and competitiveness. The results vary widely between the studies, but the resulting transport biofuel market shares are mainly below 40% during the entire time periods analysed. Some of the reviewed studies show higher transport biofuel market shares in the medium (15–30 years) than in the long term (above 30 years), and, in the long‐term models, at the end of the modelling horizon, transport biofuels are often substituted by electric and hydrogen cars.  相似文献   

8.
The purpose of this study is to explore the main correlates of male height in 105 countries in Europe & overseas, Asia, North Africa and Oceania. Actual data on male height are compared with the average consumption of 28 protein sources (FAOSTAT, 1993–2009) and seven socioeconomic indicators (according to the World Bank, the CIA World Factbook and the United Nations). This comparison identified three fundamental types of diets based on rice, wheat and milk, respectively. The consumption of rice dominates in tropical Asia, where it is accompanied by very low total protein and energy intake, and one of the shortest statures in the world (∼162–168 cm). Wheat prevails in Muslim countries in North Africa and the Near East, which is where we also observe the highest plant protein consumption in the world and moderately tall statures that do not exceed 174 cm. In taller nations, the intake of protein and energy no longer fundamentally rises, but the consumption of plant proteins markedly decreases at the expense of animal proteins, especially those from dairy. Their highest consumption rates can be found in Northern and Central Europe, with the global peak of male height in the Netherlands (184 cm). In general, when only the complete data from 72 countries were considered, the consumption of protein from the five most correlated foods (r = 0.85) and the human development index (r = 0.84) are most strongly associated with tall statures. A notable finding is the low consumption of the most correlated proteins in Muslim oil superpowers and highly developed countries of East Asia, which could explain their lagging behind Europe in terms of physical stature.  相似文献   

9.
D. J. Morré 《Protoplasma》1995,184(1-4):14-21
Summary An NADH oxidase activity of the plasma membrane that was growth factor- and hormone-stimulated has been reported and characterized extensively. The activity is constitutively activated in cancer. Thiol groups are important to its activity and its activity as a thiol oxidoreductase or thiol interchange activity may be important to its functioning in growth and membrane trafficking. The activity is inhibited in the presence of GDP and brefeldin A and appears to be found not only at the plasma membrane but also with the Golgi apparatus. The phenotype of an inhibited NADH oxidase is a failure of cells to enlarge. The hypothesis under investigation is that the hormone- and growth factor-stimulated NADH (quinone)/thiol oxidase functions as an essential component of physical membrane displacements associated with cell elongation, vesicle budding and pleomorphic membrane changes in both animal and plant cells.  相似文献   

10.
This study describes the growth characteristics of Aymara children living in Ancoraimes, Bolivia at altitudes between 3800 and 4000 meters. Anthropometric measurements were made on 510 children between the ages of 6. 0 and 20. 9 years, 360 males and 150 females. The growth pattern of Ancoraimes Aymara children is very similar to that of other high altitude Andean populations. They are greatly delayed in height and weight, exhibit little sexual dimorphism in body size and relative to stature, have larger chest dimensions than U.S. children. Compared to Quechua children living at higher altitudes in Peru, Ancoraimes children tend to be taller and heavier but have significantly smaller chest dimensions. Although the causes of the size differences between these two groups are not entirely clear, they may be due to the different altitudes at which the groups reside.  相似文献   

11.
4 种不同脂肪源对太平洋鲑生长和体组成的影响   总被引:6,自引:0,他引:6  
在日粮中添加11.5%的4 种不同来源脂肪饲养180 尾初始重约为110g 的太平洋鲑(Oncorhynchus spp.)于水泥池中56d。实验分4 组,每组3个平行池,每池15尾鱼。研究日粮中4 种不同来源脂肪对淡水养殖太平洋鲑生长性能、体组成与品质的影响。4 组脂肪源分别为鱼油(实验1 组)、大豆油(实验2 组)、大豆磷脂(实验3 组)和玉米油(实验4 组)。实验表明:(1) 实验各组太平洋鲑存活率相似,但大豆磷脂组的特定生长率显著好于鱼油组、大豆油组和玉米油组(P0.05)。大豆磷脂组、大豆油组和玉米油组的饲料效益显著好于鱼油组(P< 0.05); (2) 大豆油组、大豆磷脂组和玉米油组太平洋鲑肠系膜脂肪与肝脏脂肪含量不同程度低于鱼油组,而肌肉中脂肪含量不同程度低于鱼油组; (3) 实验各组太平洋鲑肝脏脂肪、肌肉脂肪和肠脂中总多不饱和脂肪酸组成基本相似,但玉米油组、大豆磷脂组和大豆油组太平洋鲑总n-3 多不饱和脂肪酸比例较鱼油组显著下降,而总n-6 系多不饱和脂肪酸比例显著提高(P<0.05);(4) 玉米油组、大豆磷脂组和大豆油组太平洋鲑血浆中脂肪分解酶、甘油三酯和高密度脂蛋白指标较鱼油组不同程度上升;(5) 实验各组太平洋鲑解剖组织学检查未见异常病理变化。实验结果表明,淡水养殖条件下,太平洋鲑日粮中脂肪以添加大豆磷脂的生长性能最好,大豆油、玉米油和鱼油效果相似,添加玉米油、大豆磷脂和大豆油均不影响太平洋鲑健康状况和品质。    相似文献   

12.
The circumstances surrounding the first study of human growth, published in 1754, are described. Jampert, who made this study, died young and his work was not recognised, indeed remained completely unknown between 1778 and 1981. The content of the work is briefly described.  相似文献   

13.
In [Quince, et al., 2008. Biphasic growth in fish I: Theoretical foundations. J. Theor. Biol., doi:10.1016/j.jtbi.2008.05.029], we developed a set of biphasic somatic growth models, where maturation is accompanied by a deceleration of growth due to allocation of energy to reproduction. Here, we use growth data from both hatchery-raised and wild populations of a large freshwater fish (lake trout, Salvelinus namaycush) to test these models. We show that a generic biphasic model provides a better fit to these data than the von Bertalanffy model. We show that the observed deceleration of somatic growth in females varies directly with gonad weight at spawning, with observed egg volumes roughly 50% of the egg volumes predicted under the unrealistic assumption of perfectly efficient energy transfer from somatic lipids to egg lipids. We develop a Bayesian procedure to jointly fit a biphasic model to observed growth and maturity data. We show that two variants of the generic biphasic model, both of which assume that annual allocation to reproduction is adjusted to maximise lifetime reproductive output, provide complementary fits to wild population data: maturation time and early adult growth are best described by a model with no constraints on annual reproductive investment, while the growth of older fish is best described by a model that is constrained so that the ratio of gonad size to somatic weight (g) is fixed. This behaviour is consistent with the additional observation that g increases with size and age among younger, smaller breeding females but reaches a plateau among older, larger females. We then fit both of these optimal models to growth and maturation data from nineteen wild populations to generate population-specific estimates of ‘adapted mortality’ rate: the adult mortality consistent with observed growth and maturation schedules, given that both schedules are adapted to maximise lifetime reproductive output. We show that these estimates are strongly correlated with independent estimates of the adult mortality experienced by these populations.  相似文献   

14.
Effectively adapting to climate change involves overcoming social and ecological system barriers. The present study uses a three‐phase adaptation framework to propose adaptation strategies aimed at overcoming socioecological barriers of the food–energy–water (FEW) nexus. Cradle‐to‐farm‐gate land, greenhouse gas (GHG), and water impacts—that derive from food consumption in the United States—are analyzed and differentiated by major demographic groups (Black, Latinx, and White). Results indicate that the White demographic yields the highest per capita GHG (680 kg of CO2 eq?year?1) and water impacts (328,600 L?year?1) from food consumption, whereas the Black demographic yields the highest per capita land impacts (1,770 m2?year?1) from food consumption. Our findings suggest that obtaining data with the intention of building consensus across sociodemographic lines overcomes barriers in the understanding phase, leading to increased social receptivity for many planning and managing phase processes. Specifically, we find that identifying and developing leaders who possess the cognitive and interpersonal capacity to manage many variables and stakeholders is key to assessing and selecting adaptation options in the planning phase. We also propose using government programming to encourage environmentally friendly food purchasing behavior. Then, we discuss how our proposals could be used in adaptation feasibility and evaluation activities in the managing phase. In all, these findings facilitate the development of improved climate change adaptation and policy by satisfying the understanding phase of the climate change adaptation framework, establishing a cross‐disciplinary methodological approach to addressing socioecological problems, and providing useful FEW impact data for FEW nexus and climate change researchers.  相似文献   

15.
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   

16.
Whether Hymenolepis diminuta (Cestoda: Cyclophyllidea) might affect adversely the growth of its host under normal conditions was studied. Rats were divided into four experimental groups: (1) rats infected with the tapeworm and fed ad libitum, (2) uninfected rats fed ad libitum, (3) and infected rats fed isocalorically with (4) uninfected rats. Growth rates of infected rats did not differ from infected animals. Infected, meal fed rats limited to 15 g synthetic diet/day grew as rapidly as their uninfected counterparts, and infected rats fed ad libitum did not consume more food than the comparable infected group. There were no significant differences in consumption or in excrement produced between groups (1) and (2) and groups (3) and (4). Weights attained by the worms were not affected by mode of host feeding (ad libitum or meal fed), whether expressed as wet or dry weight. Since H. diminuta appears not to affect nutrient utilization or consumption in a healthy, unstressed host, at least on a gross level, it probably should be considered an endocommensal.  相似文献   

17.
Heparan sulfates (HS) are highly modified sugar polymers in multicellular organisms that function in cell adhesion and cellular responses to protein signaling. Functionally distinct, cell type-dependent HS modification patterns arise as the result of a conserved network of enzymes that catalyze deacetylations, sulfations, and epimerizations in specific positions of the sugar residues. To understand the genetic interactions of the enzymes during the HS modification process, we have measured the composition of HS purified from mutant strains of Caenorhabditis elegans. From these measurements we have developed a genetic network model of HS modification. We find the interactions to be highly recursive positive feed-forward and negative feedback loops. Our genetic analyses show that the HS C-5 epimerase hse-5, the HS 2-O-sulfotransferase hst-2, or the HS 6-O-sulfotransferase hst-6 inhibit N-sulfation. In contrast, hse-5 stimulates both 2-O- and 6-O-sulfation and, hst-2 and hst-6 inhibit 6-O- and 2-O-sulfation, respectively. The effects of hst-2 and hst-6 on N-sulfation, 6-O-sulfation, and 2-O-sulfation appear largely dependent on hse-5 function. This core of regulatory interactions is further modulated by 6-O-endosulfatase activity (sul-1). 47% of all 6-O-sulfates get removed from HS and this editing process is dependent on hst-2, thereby providing additional negative feedback between 2-O- and 6-O-sulfation. These findings suggest that the modification patterns are highly sensitive to the relative composition of the HS modification enzymes. Our comprehensive genetic analysis forms the basis of understanding the HS modification network in metazoans.  相似文献   

18.
A comprehensive understanding of protein–protein interactions is an important next step in our quest to understand how the information contained in a genome is put into action. Although a number of experimental techniques can report on the existence of a protein– protein interaction, very few can provide detailed structural information. NMR spectroscopy is one of these, and in recent years several complementary NMR approaches, including residual dipolar couplings and the use of paramagnetic effects, have been developed that can provide insight into the structure of protein–protein complexes. In this article, we review these approaches and comment on their strengths and weaknesses.  相似文献   

19.
西农莎能山羊间性遗传机制研究   总被引:3,自引:0,他引:3  
詹铁生  刘景喜 《遗传学报》1994,21(5):356-361
本文从解剖学、组织学、细胞遗传学及遗传学方面对西农药莎能山羊的间性个性进行了研究。发现从雌性假间性到性逆转雄性的一系列类型的间性,全部是遗传雌性(60,XX),核型正常。这些间性个体完全受基因作用,使雌性转化,引起性别异常,因而间性基因是雄性化基因,位于常染色体,属隐性遗传。  相似文献   

20.
T Shimizu  T Ono  T Yoshida  F Cho  N Goto 《Jikken dobutsu》1988,37(2):145-151
We describe the relative growth in infant cynomolgus monkeys (Macaca fascicularis). The multivariate analyses using the principal component analysis and multivariate allometric analysis were applied to biometrical data of laboratory-bred cynomolgus monkeys aged from birth to 12 weeks. All the animals had been bred and reared under uniform environmental conditions at Tsukuba Primate Center for Medical Science, N. I. H., Japan. As the result of the principal component analysis, the cumulative contribution ratio of the 1st and 2nd principal components (PC1 and PC2) accounted for 88.2% and 85.7% in males and females, respectively. This indicates that the morphologic traits (15 traits) grow normally in size, but the analysis did not detect any differences in growth rate among the traits. So, the multivariate allometric analysis was applied to the same data. The traits concerning the face and truck showed relatively high growth rates compared to head breadth, whereas the limbs and arms grew slowly.  相似文献   

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