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Little is known about how beliefs about heredity as a cause of health conditions might influence preventive and interpersonal behaviors among those individuals with low genetic and health literacy. We explored causal beliefs about podoconiosis, a neglected tropical disease (NTD) endemic in Ethiopia. Podoconiosis clusters in families but can be prevented if individuals at genetically high risk wear shoes consistently. Adults (N = 242) from four rural Ethiopian communities participated in qualitative assessments of beliefs about the causes of podoconiosis. Heredity was commonly mentioned, with heredity being perceived as (1) the sole cause of podoconiosis, (2) not a causal factor, or (3) one of multiple causes. These beliefs influenced the perceived controllability of podoconiosis and in turn, whether individuals endorsed preventive and interpersonal stigmatizing behaviors. Culturally informed education programs that increase the perceived controllability of stigmatized hereditary health conditions like podoconiosis have promise for increasing preventive behaviors and reducing interpersonal stigma.  相似文献   
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This study examined the relationship between performance on the Portland Digit Recognition Test (PDRT) and the MMPI-2 in a group of veterans who were suspected of having motivation to exaggerate cognitive and/or psychiatric symptoms. Number correct on “easy” trials on the PDRT correlated inversely with MMPI-2 measures of psychopathology, whereas number correct on “hard” trials positively correlated with the same scales. Some individuals performed poorly across both types of PDRT trials and had significant MMPI-2 elevations, whereas others performed poorly only on “hard” PDRT trials and had less extreme MMPI-2 elevations. This study reinforces the need to assess the validity of both cognitive and psychiatric symptom complaints.  相似文献   
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Patients with alien hand syndrome (AHS) experience making apparently deliberate and purposeful movements with their hand against their will. However, the mechanisms contributing to these involuntary actions remain poorly understood. Here, we describe two experimental investigations in a patient with corticobasal syndrome (CBS) with alien hand behaviour in her right hand. First, we show that responses with the alien hand are made significantly more quickly to images of objects which afford an action with that hand compared to objects which afford an action with the unaffected hand. This finding suggests that involuntary grasping behaviours in AHS might be due to exaggerated, automatic motor activation evoked by objects which afford actions with that limb. Second, using a backwards masked priming task, we found normal automatic inhibition of primed responses in the patient's unaffected hand, but importantly there was no evidence of such suppression in the alien limb. Taken together, these findings suggest that grasping behaviours in AHS may result from exaggerated object affordance effects, which might potentially arise from disrupted inhibition of automatically evoked responses.  相似文献   
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Sequestration of Plasmodium falciparum-infected erythrocytes is a pathological feature of fatal cerebral malaria. P. falciparum is genetically diverse among, and often within, patients. Preferential sequestration of certain genotypes might be important in pathogenesis. We compared circulating parasites with parasites sequestered in the brain, spleen, liver, and lung in the same Malawian children with fatal malaria, classifying serotypes using antibodies to merozoite surface proteins 1 and 2 and immunofluorescence in order to differentiate parasites and to quantify the proportions of each serotype. We found (i) similar distributions of various serotypes in different tissues and (ii) concordance between parasite serotypes in peripheral blood and parasite serotypes in tissues. No serotypes predominated in the brain in cerebral malaria, and parasites belonging to a single serotype did not cluster within individual vessels or within single tissues. These findings do not support the hypothesis that cerebral malaria is caused by cerebral sequestration of certain virulent types.  相似文献   
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The prevalence of food allergy: a meta-analysis   总被引:7,自引:2,他引:5  
BACKGROUND: There is uncertainty about the prevalence of food allergy in communities. OBJECTIVE: To assess the prevalence of food allergy by performing a meta-analysis according to the method of assessment used. METHODS: The foods assessed were cow's milk, hen's egg, peanut, fish, shellfish, and an overall estimate of food allergy. We summarized the information in 5 categories: self-reported symptoms, specific IgE positive, specific skin prick test positive, symptoms combined with sensitization, and food challenge studies. We systematically searched MEDLINE and EMBASE for publications since 1990. The meta-analysis included only original studies. They were stratified by age groups: infant/preschool, school children, and adults. RESULTS: A total of 934 articles were identified, but only 51 were considered appropriate for inclusion. The prevalence of self-reported food allergy was very high compared with objective measures. There was marked heterogeneity between studies regardless of type of assessment or food item considered, and in most analyses this persisted after age stratification. Self-reported prevalence of food allergy varied from 1.2% to 17% for milk, 0.2% to 7% for egg, 0% to 2% for peanuts and fish, 0% to 10% for shellfish, and 3% to 35% for any food. CONCLUSION: There is a marked heterogeneity in the prevalence of food allergy that could be a result of differences in study design or methodology, or differences between populations. CLINICAL IMPLICATIONS: We recommend that measurements be made by using standardized methods, if possible food challenge. We need to be cautious in estimates of prevalence based only on self-reported food allergy.  相似文献   
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