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The Kahnawake Schools Diabetes Prevention Project (KSDPP) is an ongoing participatory research and intervention project aimed at the primary prevention of type 2 diabetes. Formally initiated in 1994 with strong community support, KSDPP provides a fertile opportunity to learn about how a community came to identify the need for preventive action on a health problem such as diabetes. The purpose of our study was to describe the various conditions in the community of Kahnawake, which gave rise to its mobilization for the prevention of type 2 diabetes. Qualitative data consisted of 12 individual interviews and one focus group with key community members and health professionals living and/or working in the community of Kahnawake, along with historically relevant documents. The data collection and analysis procedures of the grounded theory method were applied. Results describe a preceding phase to formal KSDPP implementation, triggered by returning research results on the community prevalence of type 2 diabetes. This phase of 'legitimizing diabetes as a community health issue' is characterized by a shift in the perceived preventability of diabetes among community members; from a problem that was to be lived with to a problem that was to be prevented. The shift in perceptions was facilitated by the context in the community, described by structural developments, cognitive and relational elements. In addition to reaffirming the critical importance of utilizing lay knowledge during the planning of a health promotion intervention, our study has uncovered some of the key conditions through which individuals in the community came to participate in the identification and planning of a diabetes prevention project.  相似文献   
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A sample of Aedes aegypti (L.) from Santiago de Cuba, Cuba, with a high level of temephos resistance (19.58x at the 50% lethal concentration [LC50]), was subjected to temephos selection to evaluate the utility of this organophosphate insecticide for mosquito control. High resistance developed after six generations of selection (200.00x). Little or no cross-resistance was observed to the organophosphates, malathion and fenitrothion, but high cross-resistance was observed for the pyrethroid deltamethrin (337.5x) and the organophosphate fenthion (12.74x). Synergism tests implicated detoxifying esterases in temephos and fenthion resistance and deltamethrin resistance was associated with a cytochrome P450 monooxygenasa. Biochemical tests, polyacrylamide gel electrophoresis (PAGE), and inhibition studies confirmed the presence of elevated esterase activity associated with temephos resistance. Pyrethroid resistance could be associated with a glutathione-S-transferase mechanism but not the esterases. The cross-resistance to deltamethrin from temephos selection could limit the use of both insecticides for Ae. aegypti control.  相似文献   
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Background  

South African households are severely affected by human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) but health and economic impacts have not been quantified in controlled cohort studies.  相似文献   
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1. gamma-Aminobutyric acid (GABA) inhibited the antidiuretic response and the increased urinary excretion of vasopressin produced by carbachol when both drugs were injected into a lateral cerebral ventricle (i.c.v.) in the water-loaded rat under ethanol anaesthesia. 2. The inhibitory effect of GABA was mimicked by muscimol and 3-amino-1-propane sulphonic acid (3-APS) and blocked by bicuculline. 3. GABA injected i.v. or into the cisterna magna (i.cist.) did not inhibit the release of vasopressin by carbachol injected i.c.v. 4. The results suggest a role for GABA as a putative inhibitory transmitter in the hypothalamo-neurohypophysial system, acting directly on the supraoptic or paraventricular nuclei in the anterior hypothalamus.  相似文献   
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The ethnobotanical uses of South American species of Strychnos L. (Loganiaceae) are reviewed, with the exception of their major r?le in the preparation of curare, which will be dealt with in detail elsewhere. Medicinal uses are less common than is the case with the African and Asian species of the genus. About 140 samples, mostly of leaves, belonging to 53 species, have been screened for alkaloids. As with species from other parts of the world, the stem bark and root bark tend to be a richer source than leaves. Nor-harman is present in extracts from S. barnhartiana leaves. Pyridino-indolo-quinolizidinone (angustine-type) bases are also found in several species. The occurrence and pharmacology of the (non-curarizing) alkaloids known to be present in South American Strychnos species is reviewed.  相似文献   
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