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91.
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Before 1989, dengue epidemiology in Sri Lanka was characterized by frequent transmission of all four dengue serotypes but a low incidence of dengue hemorrhagic fever (DHF). After 1989, cases of DHF dramatically increased. Here we present the results of epidemiologic studies conducted in Colombo, Sri Lanka before and after epidemic emergence of DHF in 1989. We compared the proportion of dengue cases among people with fever attending clinics from 1980 to 1984 and in 1997 and 1998 to determine if an increase in dengue transmission was associated with more DHF cases being reported. We also compared the relative distribution of dengue virus serotypes circulating in Colombo before and after the emergence of DHF. We detected no significant differences in dengue as a proportion of fever cases or in serotype distribution between the pre and post-DHF periods. We conclude that an increase in virus transmission or a change in circulating serotypes does not explain the epidemic emergence of DHF in Sri Lanka.  相似文献   
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Bivalent ligands have been developed for a variety of G protein-coupled receptor targets, including opioid, dopamine, serotonin and muscarinic receptors. The most successful application of the bivalent ligand approach has been in the development of selective opioid antagonists, such as norbinaltorphimine. Several important principles have emerged from the study of norbinaltorphimine and related compounds, including the utility of bivalent ligands for targeting particular receptor classes and serving as a scaffold for specific interactions with unique amino acid residues that render receptor subtype selectivity. In recent years, several novel bivalent compounds were synthesized and characterized for activity at muscarinic receptors. The compounds display an interesting profile of high binding affinity, strong agonist potency and receptor subtype selectivity. Bivalent ligands represent an important starting point for the development of selective muscarinic agonists with potential utility in treating a variety of neurological disorders, including Alzheimer's disease and schizophrenia. The bivalent ligand approach may be generally applicable to other G protein-coupled receptors.  相似文献   
95.
ObjectiveThis study aimed to examine the dietary intake of Salvadoran households according to perceived access to healthy meals (PAHD), and to identify household characteristics associated with diet quality and PAHD.MethodsSecondary data analysis with a sample of 139 Salvadoran households from resource-poor communities in El Salvador. Chi-square tests and ANOVA were used to assess differences in dietary intake across households classified according to PAHD.ResultsHigh-PAHD households had higher women's education, household food security levels, overall diet quality, and variety, and higher intakes of animal products, fats, cholesterol, vitamin C, and sodium (P < .05). Diet quality was not associated with the household characteristics studied.Conclusions and ImplicationsOverall diet quality was associated with higher levels of PAHD, but some differences in intakes were not as expected, such as higher intakes in foods and nutrients associated with low-quality diets, among high PAHD households.  相似文献   
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Promotion of mouthguards among amateur football players in Victoria   总被引:2,自引:0,他引:2  
Abstract: Wearing mouthguards while playing contact sports reduces the prevalence and severity of orofacial injuries. We report on a 1991–92 promotion of mouthguard use among amateur football players in Melbourne. Four questionnaires were completed by players (1991 season: middle: n =638, 49 per cent response; late: n =770, 51 per cent; 1992: early: n =505, 26 per cent; late: n =698, 54 per cent), in four age groups (16–19, 20–23, 24–29, 30–44 years), about perceived mouthguard value and usage, injury experience, and awareness of a promotional message. Over the two seasons, mouthguard ownership and consistent wear increased and dental injuries decreased. Ownership of mouthguards increased among: 20–23 year olds and 30–44 year olds (13 and 16 per cent); managers, tradespersons, salespersons, labourers and the unemployed (14–19 per cent); residents of northern and western regions (12 and 13 per cent); those with 6 to 10 years of education (29 per cent); players in old boys' networks (13 per cent); and those with English as a first language (8 per cent). Consistent wear was high at matches (89 per cent) but low at training (13 per cent), owing to perceived lack of physical contact. Of dental injuries reported by 25–31 per cent, fractures predominated over luxations and avulsions. Fractures and avulsions were more common at matches than training; luxations predominated at training. When a mouthguard was not worn, the likelihood of a fractured or avulsed tooth was at least twice that when a mouthguard was worn. Some injuries occurred despite the wearing of mouthguards. The promotional message appeared effective in increasing mouthguard use; newspapers and football journals provided effective message locations for players, and ground signs and the electronic scoreboard for spectators.  相似文献   
99.
OBJECTIVES: Pediatric chronic physical illness and adult psychiatric disorders are substantial sources of burden for family care-takers, but little attention has been paid to parental burden resulting from children's or adolescents' psychiatric disorders. This paper describes the predictors of perceived parental burden and its impact on the use of specialty mental health and school services. METHODS: A representative general population sample of 1015 9-, 11-, and 13-year-olds and their parents completed structured psychiatric diagnostic interviews and the Child and Adolescent Burden Assessment. RESULTS: Weighted estimates indicated that 10.7% of parents in the general population perceived burden resulting from their children's symptomatology. Significant predictors of perceived burden were levels of child symptomatology and impairment and parental mental health problems. Children's depressive and anxiety disorders were associated with less burden than other diagnoses. The effects of child disorder severity on specialty mental health service use appeared to be mediated by the level of burden induced. CONCLUSIONS: Substantial levels of parental burden resulted from child psychiatric disorders and were a major reason for specialist mental health service use.  相似文献   
100.
Over the past decade, considerable effort was focused on the development of muscarinic and nicotinic agonists for the treatment of Alzheimer's disease. The rationale for developing muscarinic agonists was based on the role of acetylcholine in learning and memory function and the consistent neurochemical finding that cholinergic neurons degenerated in Alzheimer's patients. Thus far, the clinical utility of muscarinic agonists remains unproven, yet recent studies suggest that muscarinic agonists might be useful in treating not only memory deficits, but also psychiatric disturbances and some of the underlying causes of Alzheimer's disease, such as the deposition of Abeta. In addition, nicotinic receptors may play a role in cognitive function and help regulate the toxicity of amyloid precursor protein. Ultimately, cholinergic agonists may prove useful in the treatment of Alzheimer's disease.  相似文献   
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