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Abstract: Data from the National Education Longitudinal Study were combined with census data at the zip code level to examine the impact of neighborhood racial and ethnic diversity and consolidated inequality, in addition to individual, family, and school factors, on the likelihood of dropping out of high school. Results indicate that while the effects for diversity and consolidated inequality did not support the stated hypotheses, main effects for family risk and prior academic achievement were significant and in the stated direction. Also, when controlling for individual, family, school, and neighborhood characteristics, African Americans were less likely than White students to drop out of school. Implications for contextual effects research and educational outcomes are discussed.  相似文献   
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Objective: To document the breastfeeding practices of Aboriginal mothers delivering in Perth. Design and methods: A cohort of mothers was followed from the time of delivery for six months to obtain details of infant feeding practices. Subjects: A total of 455 mothers delivered during the study period and were asked to participate. A total of 425 mothers completed the initial questionnaire. Setting: The study was undertaken in six public hospitals in Perth, Western Australia. Data analyses: The data were analysed using spss . Breastfeeding duration was calculated using Kaplan–Meier survival analysis. Main outcome measures: Breastfeeding initiation and duration. Results: The mean age of the Aboriginal mothers was 21.8 years (range 14–39 years, SD 5.32) and the average gestational age was 38.3 weeks. Almost 50% of the mothers in the study delivered by Caesarean section. At discharge from hospital 89.4% (CI 86.6–92.1) of mothers were breastfeeding, declining to 58.8% (CI 53.5–64.1) at six months. When compared with non‐Aboriginal mothers, the Aboriginal breastfeeding rates were higher than the non‐Aboriginal average breastfeeding rates, but lower than the highest socioeconomic group. Conclusions: The breastfeeding rates of Aboriginal mothers are higher than for other Australians. This is despite the low maternal age and level of education and the high rates of low‐birth‐weight infants and Caesarean section among this population. The World Health Organization recommendation for infant feeding is exclusive breastfeeding until six months, but less than one‐third of Aboriginal mothers achieved this recommendation.  相似文献   
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OBJECTIVE: To determine the cost-effectiveness of induction of labour versus serial fetal monitoring while awaiting spontaneous labour in postterm pregnancies. DESIGN: Cost-effectiveness and cost-minimization analyses conducted as part of a Canadian multicentre randomized clinical trial. SETTING: Twenty-two Canadian hospitals, of which 19 were teaching hospitals and 3 were community hospitals. PATIENTS: Women with uncomplicated pregnancies of 41 or more weeks' gestation were randomly assigned to induction of labour or serial antenatal monitoring. Of the 3418 women enrolled, no data were received on 11. Therefore, results were based on data from 1701 women in the induction arm of the study and 1706 women in the monitoring arm. MAIN OUTCOME MEASURES: Perinatal mortality and neonatal morbidity, rates of cesarean section and health care costs. Hospital costing models were developed specifically for the study. Data on use of major resources (e.g., length of hospital stay, surgical procedures, major diagnostic tests and procedures, and medications) for all trial participants were collected and combined with data on minor tests and procedures (e.g., laboratory tests) abstracted from a detailed review of medical records of a sample of patients. RESULTS: Because the results of the clinical trial showed a nonsignificant difference in perinatal mortality and neonatal morbidity between the induction and monitoring arms, the authors conducted a cost-minimization rather than a cost-effectiveness analysis. The mean cost per patient with a postterm pregnancy managed through monitoring was $3132 (95% confidence interval [CI] $3090 to $3174) and per patient who underwent induction of labour was $2939 (95% CI $2898 to $2981), for a difference of $193. The significantly higher (p < 0.0001) mean cost per patient in the monitoring arm was due mainly to the costs of additional monitoring and the significantly higher rates of cesarean section among these patients. Estimated conservatively, the savings resulting from a universal policy of managing postterm pregnancies by induction of labour in Canada may be as high as $8 million a year. CONCLUSIONS: A policy of managing postterm pregnancy through induction of labour not only results in more favourable outcomes than a monitoring strategy but does so at a lower cost.  相似文献   
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Extrarenal angiomyolipomas of the perinephric space.   总被引:4,自引:0,他引:4  
We describe 2 cases of extrarenal angiomyolipoma of the perinephric space. All other cases of extrarenal angiomyolipoma of the retroperitoneum are reviewed and the clinical relevance of this unusual pathological entity is discussed.  相似文献   
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This study compares the effects of the cancer experience on various aspects of marital and sexual functioning (e.g., communication, emotional support, body image, sexual satisfaction and frequency) for two groups of long-term cancer survivors (testicular cancer and Hodgkin's disease) and their spouses. Comparisons between the two patient groups showed significantly more survivors of Hodgkin's disease than testicular cancer reporting the emergence of special issues and changes in the marital relationship. No differences emerged between the spouse groups on sexual functioning variables; however, spouses of survivors of Hodgkin's disease were more likely than spouses of survivors of testicular cancer to report the development of special issues and communication difficulties. A substantial proportion of both survivor groups disclosed negative changes in body image and sexual frequency. Majorities of both survivors and spouses acknowledged that the illness had drawn them closer together. When representative marital/sexual functioning variables were used to predict Family Environment Scale (FES) scores for survivors and for spouses, changes in the spouse's importance, influence of the illness on the relationship, and changes in sexual frequency emerged as significant predictors. The clinical significance of long-term changes in marital and sexual functioning for the couple and the need for therapeutic interventions are discussed.  相似文献   
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Partial thickness burns (PTB) usually heal within 3 weeks. Prevention of infection and desiccation of the wounds are crucial for optimal healing. Early tangential excision of the burn eschar and allografting prevent deepening of the burns, and are therefore advocated for treatment with the best functional and aesthetic results. For superficial partial thickness burns (SPTB) conservative use of topical antimicrobial agents with frequent dressing changes are implemented. We compared the conservarive treatment for PTBs and SPTBs to grafting cryopreserved cadaveric allografts with no prior excision.

Twelve patients with flame PTB areas were allografted after mechanical debridement without excision of the burn wounds. The allografts were cadaveric skin cryopreserved by programmed freezing and stored at −180°C for 30–48 months. Matching burns for depth and area were treated with silver sulfadiazine (SSD) one to two times daily until healing or debridement and grafting were required.

It was found that 80 per cent of the cryopreserved allografts adhered well and 76 per cent of the treated areas healed within 21 days, whereas only 40 per cent of the SSD-treated burns healed within 21 days.

Partial thickness burns can be treated successfully with viable human allografts (cryopreserved cadaveric skin) with no prior surgical excision. The burn wounds heal well within 3 weeks. For deep partial thickness burns (DPTB) treatment with allografts has no advantage if they have not been previously excised.  相似文献   

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