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The Clustering of Risk Behaviors Among Caribbean Youth 总被引:2,自引:0,他引:2
Objective: To examine the relationships among risk behaviors for Caribbean youth; and to determine the correlations between initiation of sexual activity and other risk behaviors. Methods: The associations between cigarette smoking, alcohol and marijuana use, early initiation of sexual intercourse, involvement in violence and delinquency were examined using odds ratios on data from the Caribbean Youth Health Survey (n = 15,695). Survival analysis was then used to determine the association between initiation of sexual activity and the risk behaviors. Findings: There were statistically significant relationships between all pairs of risk behaviors for both male and female adolescents. Even though more males than females had engaged in each of the behaviors, the strengths of association were higher for females. From survival analysis, initiation of sexual activity was associated with gang involvement and weapon carrying among young adolescents and even more risk behaviors among the older adolescents. Conclusion: Health compromising behaviors cluster among Caribbean youth with associations being stronger for females. Initiating sexual activity was a predictor of other risk behaviors with the likelihood increasing among older adolescents and females. 相似文献
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We have previously reported evidence that megakaryocytes may play a role in bone remodeling, possibly by interactions with cells at the bone surface. To investigate the direct effects of megakaryocytes on osteoblasts, maturing megakaryocytes (CD61 positive cells) were isolated and added to cultures of human osteoblasts. Osteoblasts alone and osteoblasts treated with CD61-negative (non-megakaryocytic) cells were used as control cultures. After 48 h in culture, megakaryocytes were removed and osteoblasts immunolocalized for type-1 collagen, osteoprotegerin (OPG), and RANKL expression. Similar cultures were used for RNA extraction with mRNA for Col 1A1, OPG, and RANKL in osteoblasts measured quantitatively by RT-PCR. Osteoblasts cultured alone showed high levels of expression of collagen with 74% (+/-7) of cells staining positively. When cultured with megakaryocytes, the number of positively staining cells remained similar but the intensity of expression was increased 1.54-fold (P < 0.02). OPG was expressed by 32% (+/-6.3) of osteoblasts increasing to 51% (+/-5.5) when cultured in the presence of megakaryocytes (P < 0.01) with a 1.63-fold increase in intensity of expression (P < 0.01). In contrast, osteoblasts cultured with megakaryocytes showed suppression of RANKL expression; 35.6% (+/-5.8) of osteoblasts cultured alone stained positively decreasing to 24.3% (+/-5.3) with a 1.6-fold diminished intensity of expression (P < 0.02). Osteoblasts co-cultured with CD61-negative cells showed no differences in collagen, OPG, or RANKL expression levels compared to osteoblasts cultured alone. mRNA data supported these findings with a 3.1-fold increase in Col 1A1 expression in megakaryocyte-treated cultures compared to controls (P < 0.02). Low-level OPG mRNA expression increased 8.14-fold in osteoblasts cultured in the presence of megakaryocytes (P < 0.01), while RANKL expression was suppressed 3.3-fold (P < 0.02). These results demonstrate that in vitro, megakaryocytes have direct effects on osteoblastic production of factors affecting both bone formation and resorption. These data provide further evidence that megakaryocytes may play an important role in bone remodeling. 相似文献
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Prytherch DR Ridler BM Ashley S;Audit Research Committee of the Vascular Society of Great Britain Ireland 《The British journal of surgery》2005,92(6):714-718
BACKGROUND: Reducing the data required for a national vascular database (NVD) without compromising the statistical basis of comparative audit is an important goal. This work attempted to model outcomes (mortality and morbidity) from a small and simple subset of the NVD data items, specifically urea, sodium, potassium, haemoglobin, white cell count, age and mode of admission. METHODS: Logistic regression models of risk of adverse outcome were built from the 2001 submission to the NVD using all records that contained the complete data required by the models. These models were applied prospectively against the equivalent data from the 2002 submission to the NVD. RESULTS: As had previously been found using the P-POSSUM (Portsmouth POSSUM) approach, although elective abdominal aortic aneurysm (AAA) repair and infrainguinal bypass (IIB) operations could be described by the same model, separate models were required for carotid endarterectomy (CEA) and emergency AAA repair. For CEA there were insufficient adverse events recorded to allow prospective testing of the models. The overall mean predicted risk of death in 530 patients undergoing elective AAA repair or IIB operations was 5.6 per cent, predicting 30 deaths. There were 28 reported deaths (chi(2) = 2.75, 4 d.f., P = 0.600; no evidence of lack of fit). Similarly, accurate predictions were obtained across a range of predicted risks as well as for patients undergoing repair of ruptured AAA and for morbidity. CONCLUSION: A 'data economic' model for risk stratification of national data is feasible. The ability to use a minimal data set may facilitate the process of comparative audit within the NVD. 相似文献
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Because of the doubts cast on the safety of the sulphonylureas we analysed 1000 consecutive referrals to a diabetic clinic to identify the number of new patients equally suitable for treatment with a sulphonylurea or insulin. After excluding previously diagnosed and treated diabetics and those with a non-diabetic glucose tolerance test there were 531 new diabetics. Youth and insulin dependency, old age or obesity accounted for 390. A further 40 required diet alone, 50 had concomitant disease or socio-domestic circumstances influencing treatment choice, and 10 had secondary diabetes. Thus, only 41 diabetics (7.7% of new patients or 4.1% of total clinic referrals) appeared suitable for optional sulphonylurea or insulin therapy. We conclude that there are relatively few diabetics for whom the questionable safety of the sulphonylureas poses a therapeutic problem, and equally few who would be available for any further long-term, random-allocation trials of their effects upon the cardiovascular system. 相似文献
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A study was carried out to compare the effects of three dialysis regimens of different durations. Nineteen patients dialysed over 1975--7 for an average of only 11.2 hours per week were compared with nine dialysed for 24 hours per week (1974--6) and 10 dialysed for 27 hours (1971--3). Clinical, biochemical, and haematological results showed that the short dialysis regimen was as effective as the longer regimens, except that patients had to take a phosphate binder regularly, and that it was considerably cheaper. Short dialysis has social and economic benefits, since patients have more free time and more patients can be treated with the same number of staff and dialysis stations. As in many areas there is a shortage of places for patients needing dialysis, a short regimen is recommended. 相似文献
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