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More than 80 million African children lack access to healthy shelter, and 16 million of these children are living on the streets. This phenomenon of street children represents massive social failure as well as a violation of the United Nations Convention on the Rights of the Child. Urbanization--and the attendant processes of industrial expansion, land speculation, and "beautification"--has created a cycle of poverty, evictions, family disruption, and unwanted and abandoned children. In African cities, at least 60% of the population lives in informal, underserviced, and frequently illegal slums and squatter settlements in households generally headed by a single mother. Increasingly, eviction is being used as a strategy for driving the poor out of urban areas where they have come to seek work. Mothers who are themselves illiterate, malnourished, and constantly facing the threat of eviction are unable to meet their children's basic security needs. Moreover, violent evictions subvert children's educational and health status, cause psychological trauma and the loss of a sense of belonging, and exacerbate the household's precarious economic status. Nongovernmental organizations (NGOs) have been successful in preventing some evictions and have established programs for the care of street children. Recommended is improved coordination between NGOs and local and national governments, as exemplified by the urban child welfare task force established by the Kenyan Government. Above all, however, NGOs need to develop strategies for dealing more effectively with mass urban poverty and providing the necessary infrastructure to improve the lives of slum residents.  相似文献   
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In Hannover/Germany in 1976 a so called "Society for Regenerative Hyperbaric Therapy" (Gesellschaft für Regenerative Uberdruck-Therapie) subjected 20 patients within two coupled multi-place chambers to a simulated hyperbaric environment, equivalent to a maximum of 4 ata, followed usually by gradual reductions of the pressure. The patients were of an average age of 67.2 years and were afflicted by various disorders. During one of the "dives" a patient developed air embolism of the central nervous system. During ensuing confusion of the chamber was opened suddenly, with resultant explosive reduction of the high pressure. This resulted in five letal accidents of decompression sickness. Post mortem examination revealed diffuse distribution of gas bubbles throughout the entire body. By elecronmicroscopy each bubble was covered by an osmiophilic coat. Post mortem findings are discussed and correlated with well-known and new clinical symptomes. These observations present for the first time fatal accidents of decompression sickness in humans, associated with hyperbaric air-therapy.  相似文献   
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