首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
2.
This article examines the effect of access to health infrastructure, personnel and services on children's nutritional status in rural Nepal. Data for the study come from the 1996 Nepal Living Standards Survey, which includes individual- and household-level information on children's nutritional status and its environmental and socioeconomic determinants, and community-level information on the availability of health care infrastructure, personnel and services. The study uses a structural modelling approach to assess the relative contributions of the health care supply environment on children's anthropometric status via the pathway of maternal and child health (MCH) service use. The findings suggest that improvements in the availability of outreach clinics and the structural quality of the closest public facility would be expected to have statistically significant and large effects on the use of MCH services, and that increases in MCH service use would have a statistically significant impact on weight-for-age, but not weight-for-height or height-for-age. The overall impact of the heath care supply environment on nutritional status is assessed through a series of policy simulations.  相似文献   

3.
In South Asia women are often the primary decision-makers regarding child health care, family health and nutrition. This paper examines the proposition that constraints on women's status adversely affect the survival of their children. Survey data are used to construct indices of women's household autonomy and authority, which are then linked to longitudinal data on survival of their children. Proportional hazard models indicate that enhanced autonomy significantly decreases post-neonatal mortality. Enhanced household authority significantly decreases child mortality. A simulation based on estimated effects of eliminating gender inequality suggests that achieving complete gender equality could reduce child mortality by nearly fifty per cent and post-neonatal mortality by one-third.  相似文献   

4.
In this review, we discuss the effect of increased and decreased loading and nutrition deficiency on muscle and bone mass and strength (and bone length and architecture) independently and combined. Both exercise and nutrition are integral components of the mechanostat model but both have distinctly different roles. Mechanical strain imparted by muscle action is responsible for the development of the external size and shape of the bone and subsequently the bone strength. In contrast, immobilization during growth results in reduced growth in bone length and a loss of bone strength due to large losses in bone mass (a result of endosteal resorption in cortical bone and trabecular thinning) and changes in geometry (bone shafts do not develop their characteristic shape but rather develop a rounded default shape). The use of surrogate measures for peak muscle forces acting on bone (muscle strength, size, or mass) limits our ability to confirm a cause-and-effect relationship between peak muscle force acting on bone and changes in bone strength. However, the examples presented in this review support the notion that under adequate nutrition, exercise has the potential to increase peak muscle forces acting on bone and thus can lead to a proportional increase in bone strength. In contrast, nutrition alone does not influence muscle or bone in a dose-dependent manner. Muscle and bone are only influenced when there is nutritional deficiency--and in this case the effect is profound. Similar to immobilization, the immediate effect of malnutrition is a reduction in longitudinal growth. More specifically, protein and energy malnutrition results in massive bone loss due to endosteal resorption in cortical bone and trabecular thinning. Unlike loading however, there is indirect evidence that severe malnutrition when associated with menstrual dysfunction can shift the mechanostat set point upward, thus leading to less bone accrual for a given amount of bone strain.  相似文献   

5.
The beneficial effects of nutrition on reproduction in sheep have been described, particularly on ovulation rate. However, the relationships between nutrition and reproductive seasonality are not well known. This review will deal with the effects of body fat or food intake on sexual and hypothalamic/pituitary activity in sheep, mainly focused on Mediterranean genotypes. Although only severe malnutrition can significantly extend the length of the seasonal anestrous period, the level of fat reserves can play a significant role on reproductive seasonality delaying the onset of seasonal anoestrus, particularly on the Mediterranean environment. The effect of overfeeding on LH secretion has also been reported, specially at short term. Several experimental approaches have elucidated that both high body fat and food intake are able to modify the sensitivity of the hypothalamus to oestradiol negative feedback during seasonal anoestrus, with those effects being associated to a reduced amount of NPY mRNA and to an increase of plasma insulin, glucose and leptin concentrations, particularly in the late scenario. However, the highest receptivity to nutritional stimulation in terms of increasing LH occurs when ewes are subjected to a photoperiodic state of early anoestrus or late breeding season rather than under a photoperiod characteristic of the end of anoestrus or the beginning of the breeding season.  相似文献   

6.
On a sample of some 2000 children living in two ecologically different zones (the Wooded and Guinea savanna) in Kwara state, Nigeria, body measurements were taken, to serve as indicators of the state of nutrition. There was more undernutrition in the Guinea savanna than in the Wooded. More males than females were undernourished in the Guinea savanna but not in the Wooded. It is argued that the differences between districts stem from social and cultural variables.  相似文献   

7.
8.
The relation between the nutrition of the mother and that of her baby was assessed in a south Indian community where malnutrition is common and women do not smoke. Unselected mothers and their infants of over 37 weeks'' gestation were studied in two groups: those who paid for their care (150) and a poorer group who did not (172). There were significnat differences between the paying and non-paying groups in maternal triceps skinfold thickness, infant weight, and infant length. Overall there was a significant positive correlation between maternal triceps thickness and infant weight, length, and triceps and subscapular skinfold thickness. The correlation with the infant head circumference was less significant. These findings are further evidence that the nutrition of the mother has an important effect on the nutrition of her baby and that malnutrition is an important reason why Indian babies are lighter than European ones.  相似文献   

9.
10.
Evidence indicates that oocyte/embryo quality in the sheep is affected by nutrient status during the cycle of conception. This study aimed to determine, in the superovulated ewe, if there are stages during the peri-conception period (-18 days to +6 days relative to the day of ovulation [Day 0]) when quality is more likely to be influenced by nutrition. In Experiment 1, ewes were provided with either a 0.5 x maintenance (L), 1.0 x maintenance (M) or 1.5 x maintenance (H) diet (in terms of daily energy requirements) during the peri-conception period. Diet did not affect the mean ovulation rate (range: 15.4+/-1.47 to 16.1+/-1.55) nor the mean number of embryos collected per ewe (range: 10.9+/-2.05 to 12.4+/-1.82) but there was an increase (P<0.05) in the mean number of cells per blastocyst in the L diet (74.7+/-1.45) compared with either the M (66.4+/-1.29) or H (62.0+/-0.84) diets. This increase was due to an increase in the number of trophectoderm (Tr) cells, resulting in a shift (P<0.05) in the Tr:inner cell mass (ICM) cell ratio (range 0.69+/-0.03 to 0.73+/-0.04). In Experiment 2, six diets (HHH, MHH, MHL, MLH, MLL and LLL) were imposed during three 6-day periods commencing 12 days before and continuing until 6 days after ovulation. Although diet had minimal effect on the superovulatory response, both the mean number of cells per blastocyst and the Tr:ICM ratio were increased (P<0.05) when the L diet was provided after Day 0 (diets MHL, MLL and LLL). It is concluded that the ewe is able to respond to acute changes in nutrition imposed immediately after ovulation, resulting in changes in embryo development including cell lineage differentiation. The significance of these findings, in terms of fetal development, embryo-maternal signalling and the nutritional management of the ewe is discussed.  相似文献   

11.
The effect of potassium nutrition on pest and disease resistance in plants   总被引:4,自引:0,他引:4  
Providing a fast growing world population with sufficient food while preserving ecological and energy resources of our planet is one of the biggest challenges in this century. Optimized management of chemical fertilizers and pesticides will be essential for achieving sustainability of intensive farming and requires both empirical data from field trials and advanced fundamental understanding of the molecular processes controlling plant growth. Genes involved in plant responses to nutrient deficiency and pathogen/herbivore attack have been identified, but we are lacking information about the cross-talk between signalling pathways when plants are exposed to a combination of abiotic and biotic stress factors. The focus of this review is on the relationship between the potassium status of plants and their susceptibility to pathogens and herbivorous insects. We combine field evidence on potassium–disease interaction with existing knowledge on metabolic and physiological factors that could explain such interaction, and present new data on metabolite profiles and hormonal pathways from the model plant Arabidopsis thaliana . The latter provides evidence that facilitated entry and development of pathogens or insects in(to) potassium-deficient plants as a result of physical and metabolic changes is counteracted by an increased defence. A genetic approach should now be applied to establish a causal relationship between disease susceptibility on the one hand and individual enzymatic and signal components on the other. Once identified, these can be used to design agricultural strategies that support the nutritional status of the crops while exploiting their inherent potential for defence.  相似文献   

12.
Disorders of anxiety and fear dysregulation are highly prevalent. These disorders affect women approximately 2 times more than they affect men, occur predominately during a woman's reproductive years, and are especially prevalent at times of hormonal flux. This implies that gender differences and sex steroids play a key role in the regulation of anxiety and fear. However, the underlying mechanism by which these factors regulate emotional states in either sex is still largely unknown. This review discusses animal studies describing sex-differences in and gonadal steroid effects on affect and emotional learning. The effects of gonadal hormones on the modulation of anxiety, with particular emphasis on progesterone's ability to reduce the responsiveness of female rats to corticotropin releasing factor and the sex-specific effect of testosterone in the reduction of anxiety in male rats, is discussed. In addition, gonadal hormone and gender modulation of emotional learning is considered and preliminary data are presented showing that estrogen (E2) disrupts fear learning in female rats, probably through the antagonistic effect of ERalpha and ERbeta activation.  相似文献   

13.
The effect of nutrition on sexual development of bulls   总被引:1,自引:0,他引:1  
Most bulls that are managed for sale as yearlings are fed high-energy diets in the post-weaning period to maximize rates of gain in body weight. High-energy diets with adequate protein, vitamins and minerals result in a larger scrotal circumference at 1 y of age, however, part of this increase in size is likely due to scrotal fat. It is unclear whether testis size and spermatogenesis is significantly affected by nutritional intake in the post-weaning period. There are indications of an effect of calfhood nutrition on age at puberty and testis size. Scrotal circumference was smaller in yearling bulls raised by first-parity dams, compared to those raised by older dams. This may have been due to lower milk production by first-parity dams, an in utero effect, or both. The effect of reduced calfhood nutrition may be mediated through gonadotropin secretion. Calves destined to become later maturing bulls with smaller testes had lower amounts of LH secretion during the period of the early gonadotropin rise (8-16 wk of age). Furthermore, augmenting circulating LH concentrations at this time by treating calves with GnRH hastened pubertal development. In addition, FSH treatments in calfhood also increased scrotal circumference and hastened spermatogenesis. In that regard, FSH has been considered a main driver of Sertoli cell proliferation in prepubertal animals. Since Sertoli cell multiplication ceases at 20-25 wk of age in bulls, final testis size in bulls is likely determined in calfhood. Four experiments were done to investigate the effects of calfhood nutrition on pubertal development. These studies confirmed that superior calfhood nutrition augmented gonadotropin secretion (which is probably mediated by metabolic hormones); this resulted in larger testes at 1 y of age and an earlier onset of spermatogenesis.  相似文献   

14.
The soil/dust ingestion rate (SIR) is a crucial parameter for a human health risk assessment associated with contaminated soil. In addition, SIR levels may be influenced by demographic characteristics and geographic environments. The objectives of this study were to explore the effects of geography, age, and gender on Chinese children's SIR levels. We estimated SIRs for 210 children aged 2.5 to <12 years from three cities of China. The results showed that the mean SIR level for children aged 2.5 to <6 years (kindergarten age) was 60.8 mg d?1, significantly lower than that (91.6 mg d?1) observed for children aged 6 to <12 years (primary school age). There was no significant difference in mean SIR levels between females (78.0 mg d?1) and males (69.2 mg d?1). The mean SIR level (117.4 mg d?1) for the children group in Lanzhou was significantly higher than that for the Wuhan children group (63.0 mg d?1) and the Shenzhen children group (47.5 mg d?1). However, there was an appreciable but not statistically significant difference in SIR levels between children groups in Wuhan and Shenzhen. Our study highlights the necessity of developing SIR values for children in different geographic locations and age stages.  相似文献   

15.
Potyvirus particles are flexuous rods of 700–900?nm in length and contain one positive sense single-stranded genomic RNA molecule of approximately 10?kb, which is encapsidated by a single type of coat protein. According to available NCBI database, Potyvirus infection is prominently present in Solanaceae, Leguminosae and Cucurbitaceae families in India. Potyviruses can induce a wide range of different symptoms in infected host plants including mosaic, stripe, mottling, vein clearing, vein banding, ringspots, necrotic or chlorotic lesions, flower breaking, stunting, wilting, and most commonly lead tostunting and yield losses. PCR-based methods for the detection and identification of potyviruses rely on degenerate primers designed for conserved regions. Potyvirus infection requires the interaction of host factors with viral proteins and RNA for its replication and systemic spread, i.e interaction between VPg and eIF4E is required for Potyvirus genome translation. Mutations in host translational initiation factor eIF4E cause the conformational shift in encoded proteins which are unable to bind with viral protein (VPg), resulting in broad-spectrum Potyvirus resistance.  相似文献   

16.
PK Singh  RK Rai  L Singh 《PloS one》2012,7(9):e44901

Background

Although the urban health issue has been of long-standing interest to public health researchers, majority of the studies have looked upon the urban poor and migrants as distinct subgroups. Another concern is, whether being poor and at the same time migrant leads to a double disadvantage in the utilization of maternal health services? This study aims to examine the trends and factors that affect safe delivery care utilization among the migrants and the poor in urban India.

Methodology/Principal Findings

Using data from the National Family Health Survey, 1992–93 and 2005–06, this study grouped the household wealth and migration status into four distinct categories poor-migrant, poor-non migrant, non poor-migrant, non poor-non migrant. Both chi-square test and binary logistic regression were performed to examine the influence of household wealth and migration status on safe delivery care utilization among women who had experienced a birth in the four years preceding the survey. Results suggest a decline in safe delivery care among poor-migrant women during 1992–2006. The present study identifies two distinct groups in terms of safe delivery care utilization in urban India – one for poor-migrant and one for non poor-non migrants. While poor-migrant women were most vulnerable, non poor-non migrant women were the highest users of safe delivery care.

Conclusion

This study reiterates the inequality that underlies the utilization of maternal healthcare services not only by the urban poor but also by poor-migrant women, who deserve special attention. The ongoing programmatic efforts under the National Urban Health Mission should start focusing on the poorest of the poor groups such as poor-migrant women. Importantly, there should be continuous evaluation to examine the progress among target groups within urban areas.  相似文献   

17.
Po JY  Subramanian SV 《PloS one》2011,6(2):e16844

Background

The dimensions along which mortality is patterned in India remains unclear. We examined the specific contribution of social castes, household income, assets, and monthly per capita consumption to mortality differentials in India.

Methods and Findings

Cross-sectional data on 217 363 individuals from 41 554 households from the 2004–2005 India Human Development Survey was analyzed using multiple logistic regressions. Mortality differentials across social castes were attenuated after adjusting for household economic factors such as income and assets. Individuals living in the lowest income and assets quintiles had an increased risk of mortality with odds ratio (OR) of 1.66 (95% CI  = 1.23–2.24) in the bottom income quintile and OR of 2.94 (95% CI  = 1.66–5.22) in the bottom asset quintile. Counter-intuitively, individuals living in households with lowest monthly consumption per capita had significantly lower probability of death (OR  = 0.27, 95% CI  = 0.20–0.38).

Conclusions

Mortality burden in India is largely patterned on economic dimensions as opposed to caste dimensions, though caste may play an important role in predicting economic opportunities.  相似文献   

18.
19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号