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This study examined the mitogenic response to keratinocyte growth factor (KGF) of normal and tumour-derived human oral keratinocytes in which the degree of cellular differentiation was known and in contiguous fibroblast cultures derived from the malignant epithelial cultures. Keratinocytes, but not fibroblasts, were stimulated by KGF. There by demonstrating epithelial target cell specificity of the ligand. KGF-induced stimulation of the tumour-derived keratinocytes cultured in the absence of the 3T3 fibroblast support broadly correlated with the degree of cellular differentiation; well-differentiated keratinocytes were stimulated more by KGF than their less differentiated counterparts. Malignant oral keratinocytes expressed KGF cell surface receptors (KD 451-709 pM; receptors/cell 2306-413645), but KGF receptor mRNA did not correlate with either KGF-induced mitogenesis or the degree of epithelial cell differentiation. When the tumour-derived keratinocytes were cultured in the presence of 3T3 fibroblasts, the mitogenic response to KGF was comparable to normal epithelial cells. The results suggest that KGF-mediated growth stimulation may not be significant in providing a selective advantage for the growth of malignant keratinocytes.  相似文献   
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The pattern of infection inGlossina morsitans morsitans andG. m. centralis membrane-fed on eland, buffalo or goat blood mixed withTrypanosoma congolense orT. brucei was studied from day 1 to day 10. Tsetse were initially permissive vectors, with most flies harbouring infections of 104–105 parasites on day 3. However, after a second blood meal on day 3, flies cleared many infections withG. m. morsitans clearing more infections thanG. m. centralis. Infective feeds of goat blood consistently increased final infection rates by limiting the number of infections lost between days 3 and 6. In further experiments withG. m. morsitans only, this effect was replicated by feeding flies on erythrocytes but not on serum. These results suggest that compounds from some mammalian erythrocytes match the target specificity ofG. m. morsitans midgut lectins and, hence, have a protective effect on trypanosome establishment in the fly.  相似文献   
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It is often useful in studies of intellectual disability to be able to stratify the sample in terms of intellectual level. However, this information is sometimes difficult to obtain, and can involve a great deal of time if full IQ assessments are performed. This study explores the accuracy with which IQ scores can be projected by multiple regression from adaptive behaviour scores provided by informants. Fifty-one people with moderate, severe or profound intellectual disability received IQ assessments using the Kaufman Assessment Battery, and adaptive behaviour assessments using the Adaptive Behavior Scales (ABS). Ninety percent of projected estimates differed by less than 30% from that estimated by the K-ABC. Mean percentage divergence between actual and predicted estimates of IQ for the 51 cases for which all data were available was 15.0%. Limitations of the technique are discussed. The actual coefficients for calculating IQ are given in tabular form.  相似文献   
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Some nonprofit mental health organizations are buying real estate in order to own service delivery sites and to provide housing for clients. Owning real estate generally requires long-term financing to conserve cash. This article explores tax exempt financing methods available to nonprofit mental health organizations.  相似文献   
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Mental health centers and other government sponsored service organizations need highly effective management techniques. In this era of tightening budgets, the Japanese Management System may be a way of increasing both excellence and employee satisfaction. Managers who choose to explore this system may need a concise, written model as a guide to the ingenious, extensive, and paradoxical Japanese Management System. The System centers around quality control circles—autonomous problem-solving groups that strive for excellence. Composed of hierarchically interlocking groups, it uses a wide selection of group cohesion techniques to inspire esprit de corps, and an interlocking set of rewards governs behavior at every level. Decision making is collective (although supervisors retain veto power), and execution of ideas, once agreed upon, is quick and consistent. The System operates holistically, enthusiastically, with a high degree of excellence and mutual concern.  相似文献   
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