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941.
Children in food-insecure households may be at risk of poor health, developmental or behavioural problems. This study investigated the associations between food insecurity, potential determinants and health and developmental outcomes among children. Data on household food security, socio-demographic characteristics and children's weight, health and behaviour were collected from households with children aged 3-17 years in socioeconomically disadvantaged suburbs by mail survey using proxy-parental reports (185 households). Data were analysed using logistic regression. Approximately one-in-three households (34%) were food insecure. Low household income was associated with an increased risk of food insecurity [odds ratio (OR), 16.20; 95% confidence interval (CI), 3.52-74.47]. Children with a parent born outside of Australia were less likely to experience food insecurity (OR, 0.42; 95% CI, 0.19-0.93). Children in food-insecure households were more likely to miss days from school or activities (OR, 3.52; 95% CI, 1.46-8.54) and were more likely to have borderline or atypical emotional symptoms (OR, 2.44; 95% CI, 1.11-5.38) or behavioural difficulties (OR, 2.35; 95% CI, 1.04-5.33). Food insecurity may be prevalent among socioeconomically disadvantaged households with children. The potential developmental consequences of food insecurity during childhood may result in serious adverse health and social implications.  相似文献   
942.

Introduction

Understanding people''s perceptions of disease risk and how these perceptions compare with actual risk models may improve the effectiveness of risk communication. This study examined perceived disease risk and causal beliefs for type 2 diabetes and cardiovascular disease (CVD), the relationship between self-reported risk factors and perceived disease risk, and the influence of causal beliefs on perceived disease risk in people at increased risk.

Methods

The sample (n = 255) consisted of people who were at increased risk for diabetes and CVD (aged 57-79 y). Participants completed a postal questionnaire assessing risk factors, perceived risk, and causal beliefs for diabetes and CVD. We used regression analyses to examine the relationship between risk factors and perceived disease risk and to explore how causal beliefs affect the relationship between risk factors and perceived disease risk.

Results

Associations between risk factors and perceived diabetes and CVD risks were weak. Perceived risk, causal beliefs, and explained variance of risk factors on perceived risk were lower for diabetes than for CVD. Stronger beliefs concerning 1) overweight as a cause of diabetes and 2) smoking as a cause of CVD strengthened the association between these risk factors and perceived disease risk.

Conclusion

Although participants seemed to have some understanding of disease causation, they only partially translated their risk factors into accurate perceptions of risk. To improve understanding of risk information, health professionals may need to educate patients on how personal risk factors can contribute to the development of diabetes and CVD.  相似文献   
943.
The aim of this study was to verify the relationship between eating disorders (binge eating and bulimia nervosa) and body image dissatisfaction with BMI, anorexigenic and orexigenic factors in adolescents. Thirty-two adolescents, (13 obese [BMI=36.65±5.68] and 19 non-obese [BMI=22.18±3.11]), aged between 14 and 19y, were recruited. Symptoms of eating disorders were measured by self-report questionnaires (BSQ, BITE and BES). Hormones, cytokines and neuropeptides were determined by Elisa kits (Phoenix peptide). A positive correlation was found between: leptin and BES (r=.724), BSQ (r=.705) and BITE (r=.696); BMI and BES (r=.663), BSQ (r=.525) and BITE (r=.732); the same pattern was observed to insulin and TNF-α. A negative correlation was found in α-MSH and AgRP with BES, BSQ and BITE. Blood levels of hormones and neuropeptides could be the link between obesity and eating disorders in adolescents. However, it is not clear which is the cause and which is the consequence.  相似文献   
944.
A trend toward the reduction in the length of hospital stays has been widely observed. This increasing shift is particularly evident in perinatal care. A stay of less than 48 hours after delivery has been shown to have no negative effects on the health of either the mother or the baby as long as they receive an adequate follow‐up. This implies a close integration between hospital and community health services. The present article addresses the following questions: To what extent are postnatal services accessible to mothers and neonates? Are postnatal services in the community in continuity with those of the hospital? Are the services provided by the appropriate source of care? The authors conducted a telephone survey among 1158 mothers in a large urban area in the province of Quebec, Canada. The results were compared to clinical guidelines widely recognised by professionals. The results show serious discrepancies with these guidelines. The authors found a low accessibility to services: less than half of the mothers received a home visit by a nurse. In terms of continuity of care, less than 10% of the mothers received a follow‐up telephone call within the recommended time frame and only 18% benefited from a home visit within the recommended period. Finally, despite guidelines to the contrary, hospitals continue to intervene after discharge. This results in a duplication of services for 44.7% of the new‐borns. On the other hand, 40.7% are not seen in the recommended period after hospital discharge at all. These results raise concerns about the integration of services between agencies. Following earlier work, the present authors have grouped explanatory factors under four dimensions: the strategic dimension, particularly leadership; the structural dimension, including the size of the network; the technological dimension, with respect to information transmission system; and the cultural dimension, which concerns the collaboration process and the development of relationships based on trust.  相似文献   
945.
946.
The relative sensitivity of four benthic invertebrates (Hyalella azteca, Chironomus riparius, Hexagenia spp., and Tubifex tubifex) was determined for Cd, Cu, and Ni in water-only and in spiked-sediment exposures. Survival (median lethal concentrations [LC50s] and the concentrations estimated to be lethal to 25% of test organisms [LC25s]), and endpoints for growth and reproduction (mean inhibitory concentrations [IC25s]) were compared. The sensitivities differed depending on the species and metal, although some trends emerged. In water-only exposures, H. azteca is the most sensitive species to cadmium and nickel, with mean LC50s of 0.013 and 3.6 mg/L, respectively; C. riparius is the most sensitive species to copper, with a mean LC50 of 0.043 mg/L. In the spiked-sediment exposures, the order in decreasing sensitivity to copper is Hyalella = Hexagenia < Chironomus < Tubifex for survival and growth/reproduction. For cadmium, the order in decreasing sensitivity is Hyalella = Chironomus < Hexagenia < Tubifex, and for nickel is Hyalella < Hexagenia < Chironomus < Tubifex. Chironomus riparius and Hexagenia spp. survival can be used to distinguish between toxicity caused by different metals. Species test responses in field-collected sediment(Collingwood Harbour, ON, Canada) were examined in an attempt to determine the causative agent of toxicity throughout, using the established species sensitivities. Sediment toxicity was categorized first by comparing species responses to those established for a reference database. Test responses in the field-collected sediment do not support causality by Cu, a suspected toxicant based on comparison of sediment chemistry with sediment quality guidelines.  相似文献   
947.
Rabies virus is an important causative agent of disease resulting in an acute infection of the nervous system and death. Although curable if treated in a timely manner, rabies remains a serious public health issue in developing countries, and the indigenous threat of rabies continues in developed countries because of wildlife reservoirs. Control of rabies in wildlife is still an important challenge for governmental authorities.There are a number of rabies vaccines commercially available for control of wildlife rabies infection. However, the vaccines currently distributed to wildlife do not effectively immunize all at-risk species, particularly skunks. A replication competent recombinant adenovirus expressing rabies glycoprotein (AdRG1.3) has shown the most promising results in laboratory trials. The adenovirus vectored vaccine is manufactured using HEK 293 cells.This study describes the successful scale-up of AdRG1.3 adenovirus production from 1 to 500 L and the manufacturing of large quantities of bulk material required for field trials to demonstrate efficacy of this new candidate vaccine. The production process was streamlined by eliminating a medium replacement step prior to infection and the culture titer was increased by over 2 fold through optimization of cell culture medium. These improvements produced a more robust and cost-effective process that facilitates industrialization and commercialization. Over 17,000 L of AdRG1.3 adenovirus cultures were manufactured to support extensive field trials. AdRG1.3 adenovirus is formulated and packaged into baits by Artemis Technologies Inc. using proprietary technology. Field trials of AdRG1.3 rabies vaccine baits have been conducted in several Canadian provinces including Ontario, Quebec and New Brunswick. The results from field trials over the period 2006-2009 demonstrated superiority of the new vaccine over other licensed vaccines in immunizing wild animals that were previously difficult to vaccinate.  相似文献   
948.
The authors examined the effect of women's lifestyles on the timing of natural menopause using data from a cross-sectional questionnaire used in the United Kingdom-based Breakthrough Generations Study in 2003-2011. The analyses included 50,678 women (21,511 who had experienced a natural menopause) who were 40-98 years of age at study entry and did not have a history of breast cancer. Cox competing risks proportional hazards models were fitted to examine the relation of age at natural menopause to lifestyle and anthropometric factors. Results were adjusted for age at reporting, smoking status at menopause, parity, and body mass index at age 40 years, as appropriate. All P values were 2-sided. High adult weight (P(trend) < 0.001), high body mass index (P(trend) < 0.001), weight gain between the ages of 20 and 40 years (P(trend) = 0.01), not smoking (P < 0.001), increased alcohol consumption (P(trend) < 0.001), regular strenuous exercise (P < 0.01), and not being a vegetarian (P < 0.001) were associated with older age at menopause. Neither height nor history of an eating disorder was associated with menopausal age. These findings show the importance of lifestyle factors in determining menopausal age.  相似文献   
949.
Low doses of (5R,10S)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine (MK-801; dizocilpine) or ethanol induce less locomotor activation in inbred long-sleep (ILS) than short-sleep (ISS) mice. These differences may involve altered dopamine and/or 5-hydroxytryptamine (serotonin; 5-HT) neurotransmission. To address this possibility, the dopaminergic and serotonergic mechanisms underlying the locomotor-stimulant effects of MK-801 and ethanol in ILS and ISS mice were studied. Dopamine D1, D2 and 5-HT(2A) receptor antagonists reduced MK-801-stimulated activity in ILS mice without having any effect in ISS mice. The 5-HT reuptake inhibitor fluoxetine potentiated MK-801-stimulated activity selectively in ILS mice. Strain differences in 5-HT transporters do not explain this selective effect of fluoxetine in ILS mice since [3H]citalopram binding and [3H]5-HT uptake studies found no differences in the affinity, number or function of 5-HT transporters between ILS and ISS mice. Ethanol-induced activity in ISS mice was depressed by dopamine D2 and 5-HT(2C) receptor antagonists and enhanced by a 5-HT(1A) receptor antagonist. These results suggest that in ILS mice the locomotor-stimulant effects of MK-801 require increased dopamine and/or 5-HT neurotransmission. Conversely, in ISS mice, the effects of MK-801 appear to be monoamine-independent. Thus, even though both MK-801 and ethanol inhibit N-methyl-D-aspartate receptors, their stimulant effects appear to involve different neuronal systems.  相似文献   
950.
We examined factors associated with health care access and quality, among children in Georgia. Data from the 2007 National Survey of Children’s Health were merged with the 2008 Area Resource File. The medically underserved area variable was appended to the merged file, restricting to Georgia children ages 4–17 years (N = 1,397). Study outcomes were past-year access to care, defined as utilization of preventive medical care and no occasion of delay or denial of needed care; and quality of care received, defined as compassionate, culturally-effective, and family-centered care which was categorized as higher, moderate, or lower. Analysis included binary and multinomial logit modeling. In our study population, 80.8 % were reported to have access to care. The quality of care distribution was: higher (39.4 %), moderate (30.6 %), and lower (30.0 %). Younger age (4–9 years) was positively associated with having access to care. Compared to children who had continuous and adequate private insurance, children who were never/intermittently insured or who had continuous and inadequate private insurance were less likely to have access. Compared to children who had continuous and adequate private insurance, there were lower odds of perceiving received care as higher/moderate versus lower quality among children who were never/intermittently insured or who had continuous and inadequate/adequate public insurance. Being in excellent/very good health and living in safe/supportive neighborhoods were positively associated with quality; non-white race/ethnicity and federal poverty level were negatively associated with quality. Assuring continuous, adequate insurance may positively impact health care access and quality.  相似文献   
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