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Cohort studies have indicated that the survival of individuals with Down's syndrome has dramatically increased over the past 50 years. Early childhood survival in particular has shown major improvement, due largely to advances in cardiac surgery and in general health management. The present study was based on a continuous cohort of 1332 people with Down's syndrome in Western Australia, registered for intellectual disability services between 1953 and 2000. Their life expectancy was 58.6 years, 25% lived to 62.9 years, and the oldest living person is 73 years of age. Life expectancy for males was greater than females by 3.3 years. The substantial increase in survival across the study period means that the life expectancy of people with Down's syndrome is approaching that of the general population, but accompanied by a range of significant mid-life health problems. The findings are of relevance to all developed countries and have considerable implications in terms of the counselling information provided to families at risk of having a child with Down's syndrome.  相似文献   
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The enhancer of simian virus 40 (SV40) is active in a wide variety of tissues and hosts and thus has been called a general enhancer. Previous work has established that this region contains a number of subsegments, each with a different cell type specificity. By analyzing enhancer deletion mutants of SV40 with a restricted cell type specificity, we have identified a purine-rich DNA motif (Pu box) that is essential for activity of the mutant enhancer in lymphoid cells and also obtained evidence for an independent element that confers activity in kidney CV-1 cells. The Pu box element is positively regulated since binding of a cognate factor(s) was only observed in lymphoid cell extracts. The Pu box is also present in the 63-bp enhancer repeat of lymphotropic papovavirus (LPV), and competition experiments show that the SV40 and LPV sequences bind the same factor(s). Thus, the Pu box is likely to be a major determinant of the lymphotropic host range of LPV. In SV40, however, the Pu box is one of several enhancer elements with different cell specificities. We suggest that such an arrangement reflects a diversification strategy of SV40 to maximize its chance of adaptation to various types of host cells.  相似文献   
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Current and comprehensive information about the medical issues affecting children with Down syndrome (DS) is of value in counselling parents who are considering prenatal diagnosis and in planning services for people with DS as they age, especially given the continued improvements in their survival. Parents of school-aged children (mean age 11.37 years, 57.3% male, 42.7% female) with DS were identified by linking registers from the Disability Services Commission and the Birth Defects Registry. Less than half the children had cardiac and bowel conditions. More than half had ear conditions and more than three quarters had eye conditions. Ear, nose, and throat professionals were the specialists seen most often and the rate of tympanostomy tube insertion was nearly 17 times that of the general childhood population. Children with DS were over five times more likely to wear glasses than other children. These findings suggest that chronic, non life-threatening conditions impose a burden on families but do not threaten quality of life.  相似文献   
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The impact of lithium prophylaxis on mortality has been studied in 497 patients, 405 bipolars and 92 unipolars, who attended the same out-patient lithium clinic for up to 30 years. In order to avoid preselection, no minimum period of lithium treatment was required in our study. Of a total of 6014 patient-years, 4330 were spent in regular contact with the study clinic. General mortality due to natural causes was not significantly increased; among cardiovascular diseases, only pulmonary embolism showed an excess mortality. No patients died of lithium intoxication or chronic renal insufficiency. Patients were divided into three groups: Group A, 277 patients, attended the study clinic until death or the end of the study, Group B, 86 patients, left the clinic but continued to take lithium, and Group C, 134 patients, both left the clinic and stopped taking lithium. Among bipolars, the suicide rate compared to the general population was in excess in all three groups. Among unipolars, suicides occurred only after the patients had left the study clinic and stopped taking lithium. A special analytical method was used for intergroup comparisons of suicide rates. Bipolars in Group A attending the study clinic regularly had a suicide rate of 3.5 per 1000 patient-years. The rate increased to 6.3 or by 80 % if patients had left the clinic and did not take lithium any longer as in Group C. The suicide rate in Group C increased by 45% compared to Group B, patients who left the clinic but continued to take lithium. Our results support the hypothesis that lithium has a significant antisuicidal effect in bipolars as well as in unipolars. The suicide mortality can be further reduced by regular attendance in a specialised mood disorder clinic.  相似文献   
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This article examines the extent to which, conditional on receiving treatment, the type of care differs across metropolitan and nonmetropolitan areas. Using data from the Medical Expenditure Panel Survey (MEPS), the findings indicate that nonmetro residents who obtained mental health care (n = 2,381) have fewer mental health visits in a calendar year than their metro counterparts after adjusting for individual-level characteristics. Although observed rates of hospitalization and contact with physicians are higher in nonmetro areas than metro areas, this difference is attributable primarily to compositional differences between metro and nonmetro residents.  相似文献   
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