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1.
This paper examines young African school children's understanding of HIV and AIDS. Based on focus group interviews with children aged 7–8 in KwaZulu-Natal province, South Africa, it explores the ways in which gender and sexuality feature in their responses to the disease. Data were collected between 2003 and 2004 through 26 focus groups involving 55 boys and 64 girls. The paper argues that younger children are active agents in giving meaning to the disease. Their agency is negotiated within complex social processes involving sexual violence, highly unequal gender/age inequalities, but also sexual expression. Those expressions are subsumed however under a regime of violence and fear catapulting men, albeit with contestation, as chief vectors in the spread of the disease and a source of girls' anxieties. Children's responses to the disease are the effects of material, symbolic and discursive forces effectively constraining the opportunities available to them and creating patterns of vulnerability especially for young girls. Interventions aimed at scaling up efforts to address young children responses to the disease must be situated in parallel efforts to end poverty, sexual violence and pervasive gender inequalities in order to foster more comprehensively the exercise of young children's agency.  相似文献   
2.
Numerous studies document improvements in health status and health expectancies among older adults over time. However, most evidence is from developed nations and gender differences in health trends are often inconsistent. It remains unknown whether changes in health in developing countries resemble Western trends or whether patterns of health improvement are unique to the country's epidemiologic transition and gender norms. Using two nationally representative samples of non-institutionalized adults in China aged 65 years and older, this study investigates gender differences in the improvements in disability, chronic disease prevalence, and self-rated health from 1992 to 2002. Results from multivariate logistic regression models show that all three indicators of health improved over the 10-year period, with the largest improvement in self-rated health. With the exception of disability, the health of women improved more than men. Using Sullivan's decomposition methods, we also show that active life expectancy, disease-free life expectancy, and healthy life expectancy increased over this decade and were patterned differently according to gender. Overall, the findings demonstrate that China experienced broad health improvements during its early stages of the epidemiologic transition and that these changes were not uniform by gender. We discuss the public health implications of the findings in the context of China's rapidly aging population.  相似文献   
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Effects of gender,age, and heart rate on QT intervals in children   总被引:9,自引:0,他引:9  
The objective of this study was to determine if gender, age, and heart rate affect corrected QT intervals in children. Electrocardiograms were obtained from 781 healthy children 10–18 years of age. Corrected QT intervals were significantly (p < 0.0005) greater for girls than for boys in the entire population and for each age group over 14 years. The corrected QT interval varied inversely with age and directly with heart rate. Hence gender, age, and heart rate should be considered when diagnosing long QT syndrome.  相似文献   
5.
Because body composition is altered during head-down bed rest (HDBR), body mass can not be used as an index of energy balance. Consequently diet allowances should not be based on body mass evolution but on fat mass changes. Though criticized, skinfold thickness (ST) is the costless, easiest and fastest method to use for such an objective. The aim of this study was to compare the percentage of body fat (%BF) estimated by ST with the isotope dilution of H218O. We compiled data from three HDBR campaigns, one on women (n=8) in November 1998 and two on the same men (n=8) in December 1997 (without countermeasure) and January 1998 (with thigh-cuffs countermeasure), according to a crossover design. Body composition was assessed before and after 6 days of HDBR. %BF was derived from the biceps, triceps, sub-scapular and sup-iliac ST according to Durnin and Wormersly (1974). Fat-free mass was measured on the same day by H218O dilution and fat mass was calculated by the difference with body mass and expressed as a percentage. Based on precision tests, the minimum measurable change by ST was 1.1%BF for single measurement point. Both intercepts (F 4,30=0.89, P=0.45) and slopes (F 4,30=0.74; P=0.57) of the ST versus dilution relationships were not affected by the periods (December vs January), experimental conditions (control vs HDBR vs HDBR + thigh cuffs) or sex allowing the derivation of a common relationship %BFst=0.94 × %BFdil (F 1,47=97.9, P<0.0001; non-significant intercept excluded) with a bias between methods of −1.7±2.0 %BF (95% CI: −5.8, 2.4 %BF). ST can be used to measure %BF during HDBR provided great care is placed on training and changes are higher than 1.1 %BF. If the method can be applied for in-flight energy balance monitoring given the high observed energy deficit, a tight monitoring of the individual nutritional status as needed during simulation appears, however, dubious based on this solely method.  相似文献   
6.
Potential sex differences in amplitude, habituation, prepulse inhibition (PPI) and prepulse facilitation (PPF) of the acoustic startle response (ASR) were investigated using male and female mice from the two different inbred mouse strains C57BL/6J (C57) and C3H. Furthermore, the effects of the estrous cycle were tested. The estrous cycle appeared to have no effect on ASR amplitude, habituation, PPF and PPI, the latter being in contrast to results in rats and humans. While sex had no effect on PPI or PPF, males exhibited higher startle amplitudes than females, irrespective of strain, which we discuss to be due to increased male anxiety. In addition, long-term habituation was stronger in C57 males and short-term habituation was weaker in C3H males with respect to females. These results provide evidence for influence of the reproductive hormones on startle reactivity and startle habituation; we therefore conclude that future studies involving genetic influences on behavior using inbred strains are only complete if both sexes are included.  相似文献   
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8.
The study considers the prevalence of back pain experienced in a nationwide random sample of 2173 Icelandic school children aged 11–12 and 15–16. The study found a 20.6% prevalence of at least weekly back pain. The prevalence of back pain was significantly more frequent among the older children. No gender or class difference was found in the overall sample. Older children from rural areas have significantly more back pain than those living in the city. The need for a thorough epidemiological investigation of the association of back pain in children is emphasized.  相似文献   
9.
The aim of the study was to investigate cord blood leptin concentrations and their relationship to birth weight and gender in term pregnancies complicated by pre-eclampsia.

Cord blood samples were obtained from 52 women, identified as having pre-eclampsia, and their newborns (31 males and 21 females) immediately after birth. Specimens were analyzed using a human leptin125 I radioimmunoassay. The relationship between leptin and anthropometrics was assessed by Spearman correlation. Differences in cord blood leptin levels between male and female infants were tested with the Mann- Whitney U test. The correlation between leptin and gender was computed using the productmoment-biseral correlation analysis for continuous and dichotomous variables. The multiple logistic regression analysis examined influences of sex, birth length, birth weight, birth weight/birth length ratio, ponderal index and maternal leptin as covariates on the fetal cord leptin level.

Fetal leptin correlated positively with birth weight, length and weight/length ratio, in the total group and in the male subgroup and additionally with ponderal index in the female subgroup. Cord blood leptin concentrations in female newborns were significantly higher than in male newborns (p = 0.015), and concentrations correlated with gender (r =-0.315; p = 0.023). Multiple logistic regression analysis revealed four potential independent factors influencing fetal cord leptin: gender, birth weight, birth weight/birth length ratio and maternal leptin.

In conclusion, cord leptin concentrations in pregnancies complicated by pre-eclampsia correlate positively with birth weight and gender. Leptin concentrations in female newborns are higher compared to male newborns.  相似文献   
10.
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