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41.
Judith B. Erickson 《Child & youth care forum》1988,17(2):86-103
Several million American children are currently unsupervised during the hours between school and parents' leaving for and/or return from the workplace. Many families would prefer other arrangements, but cost or availability factors present insurmountable barriers. Although growing, the public response continues to fall far short of the need; in the meantime, private entrepreneurs are moving to fill the gaps in available services. But if these programs for school-aged children are to serve functions other than the aggrandizement of their sponsors, they must be focused on the real needs that exist among real American children. Among the real children in need of care are those who are impoverished, unsupervised, unfit physically, unprepared for the demands of school and workplace, hurried into premature adulthood, and/or disconnected from the social worlds around them. Professional child and youth care workers with experience in day care and residential settings have the preparation needed to take leadership roles in creating developmentally appropriate, effective programs to meet the emerging demands for school-age child care and to weave them into a fabric of youth-centered community services. 相似文献
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Irwin L. Flink 《Brain structure & function》2002,205(3):235-244
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Paul Hochstein Ulrich Glatzel Thomas Schmickal Andreas Wentzensen 《Trauma und Berufskrankheit》2002,4(2):s110-s114
The treatment of deep cartilage defects in load-bearing joints is a problem that still has no satisfactory solution. Full-thickness defects of the articular cartilage rarely heal spontaneously, usually leaving damage that can lead to early arthrosis. Techniques currently available for the treatment of chondral defects include abrasion, drilling, micro-fracturing, transplantation of tissue autografts and allografts, and cell transplantation. Osteochondral autograft transplantation is currently the only surgical cartilage repair technique known to lead to the formation of genuine hyaline articular cartilage and its retention at least in the medium term. The Draenert method, in which a water-cooled diamond bone-cutting system is used, is an effective procedure for resurfacing the joints affected by localised cartilaginous defects, even when there is also severe bone loss. Donor-side morbidity can be kept to a minimum by filling the defect caused by harvesting with a press-fit cylinder of cancellous bone covered with periosteum for protection. 相似文献
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Annemieke Smit-van Oosten Winston W. Bakker Harry van Goor 《Transplant international》2002,15(12):602-609
Ischemic injury plays an important role in chronic renal transplant failure (CRTF). Down-regulation of ecto-adenosine triphosphatase (ATPase) in combination with up-regulation of ecto-5'-nucleotidase is a hallmark of ischemic injury. We studied the expression of renal ecto-5'-nucleotidase and ecto-ATPase in experimental renal transplantation. Fisher 344-to-Lewis allografted rats were either treated with an angiotensin-converting enzyme inhibitor (ACEi) or left untreated. Lewis-to-Lewis syngrafted rats served as controls. Untreated allografted rats developed proteinuria, glomerulosclerosis, and mild intimal hyperplasia. ACEi completely prevented focal and segmental glomerulosclerosis (FGS) and proteinuria, but significantly enhanced intimal hyperplasia. Untreated allografted rats revealed marked vascular ecto-5'-nucleotidase activity, which increased with ACEi. Vascular ecto-5'-nucleotidase activity was absent in syngrafted animals. Ecto-5'-nucleotidase activity correlated well with intimal hyperplasia. Glomerular ecto-ATPase expression was significantly reduced in untreated allografted rats compared to syngrafted rats and correlated well with the extent of FGS. ACEi prevented reduction in glomerular ecto-ATPase. We found de-novo expression of ecto-5'-nucleotidase at sites of renal intimal hyperplasia. Glomerular ecto-ATPase expression was markedly reduced in allografted rats and was prevented by ACEi. These enzyme expression patterns suggest local ischemic damage in experimental CRTF. 相似文献
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J. Bryan Page 《Journal of urban health》2005,82(3):iii35-iii43
Contemporary discourse contains numerous examples of use of the concept of culture by social and behavioral scientists. Simple reification, where the speaker makes culture into a thing capable of action exemplifies one usage in public discourse. Some quantitative social scientists attempt to characterize people’s cultural identities by means of a single categorical variable, which often “lumps” people into categories such as “Hispanic” or “Black” that in fact have numerous culturally bounded subcategories. Approaches that emphasize cultural process are preferable to those who attempt to categorize; more complex measures of acculturation help investigators to make convincing analyses of circumstances in which health disparities occur. Examples in which investigators make appropriate use of cultural characterizations demonstrate their utility in investigating health disparities in Haitian American women, injecting and noninjecting drug users, Hispanic youth, and adult Hispanics at risk of HIV infection. Focus on culture in the study of health disparities can identify entanglements between structural factors such as poverty and lack of education and cultural factors such as beliefs about health. Qualitative methods coupled with quantitative methods have great potential to improve investigators’ grasp of cultural nuance while capturing the distribution of qualitatively derived behaviors. 相似文献
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