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101.
Infections are an uncommon cause of chronic diarrhoea. Parasites are most likely, including protozoa like giardia, cryptosporidia and cyclospora. Bacteria are unlikely to cause chronic diarrhoea in immunocompetent individuals with the possible exception of Yersinia, Plesiomonas and Aeromonas. Infectious diarrhoea can trigger other causes of chronic diarrhoea, including inflammatory bowel disease, irritable bowel syndrome and “Brainerd-type” diarrhoea. A thorough evaluation should detect most infections causing chronic diarrhoea.  相似文献   
102.
Environmental assessment and exposure reduction are a set of diagnostic and treatment techniques that work in tandem with the traditional medical approach by reducing a patient??s exposure to adverse environmental conditions as part of medical care. Assessment involves identifying the specific exposures to which a patient is sensitive and locating the corresponding contaminants in the patient??s environment. This provides a more complete diagnostic evaluation of a patient??s problem than could be obtained merely by examining the patient alone. Exposure reduction involves reducing the identified triggers to levels that are below thresholds that are associated with increased risk of sensitization and disease morbidity. Assessment of an environment for contaminants focuses on a chain of factors that include contaminant sources such as cockroaches, rodents, dust mites and fungi that excrete contaminants into an environment, facilitative factors such as moisture, food, water and shelter that help sources to thrive, and reservoirs where contaminants can accumulate prior to subsequent transport to occupants. By using this model to guide environmental assessments and their corresponding interventions, the root cause of health problems can be addressed, leading to improved quality of life for patients and reduced need for chronic medications.  相似文献   
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We describe Guatemalan birth attendants’ identification of vulnerable newborns, their evaluation of gestational age and anthropometry, and the validity of the Capurro and New Ballard newborn gestational age assessment methods. We interviewed 49 birth attendants and trained 10 of these women to assess 63 newborns. The Capurro and Ballard methods were correlated (Spearman rho = .75, p < .001) and showed agreement (Bland-Altman plot, difference and bias, ?0.33 ± 1.3 weeks). Prematurity was estimated at 27% (Ballard) and 24% (Capurro); low birth weight (LBW) was 30%. Capurro provided a simplified, equivalent estimate of gestational age compared with New Ballard that could be used by birth attendants.  相似文献   
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We surveyed cognitively normal teens with and without chronic illness regarding the perceived physical and social impact of various chronic diseases including asthma.

The overall physical impact of asthma was perceived equivalently to diabetes and arthritis, but less than epilepsy, Down's syndrome, leukemia, and human immunodeficiency virus infection. However, asthma was rated to more commonly cause physical disability (p < 0.001) and restrict activities (p < 0.0005). The social impact of asthma was perceived equivalently to diabetes, but more favorably than the other chronic diseases surveyed. Specifically, teens with asthma were perceived as having fewer behavior problems, being more honest, popular, and fun to be around, but less adept at sports. Only 6 of 149 (4%) teens surveyed expressed any degree of reluctance to befriend peers with asthma.  相似文献   
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The importance of aeroallergens as triggers for asthma is well recognized, but the relationship between asthma severity and atopic profiles in childhood has not been elucidated. This study assessed the relationship of allergen sensitization to asthma severity in a study of 114 asthmatic children followed for 8 weeks in three Southern California areas. Increased controller medication and β-agonist use were positively associated with number of positive skin tests and allergy to mold and pollens. Mold was associated with increased asthma symptoms. Degree of atopy and reactivity to mold and pollens plays a significant role in asthma severity in asthmatic children.  相似文献   
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For traditionally underserved populations, the Web can potentially unlock resources that could fundamentally improve health and wellbeing. However, there are many barriers to using Web-based content. While physical access issues are well documented, there is little understanding of how nonmainstream populations use or will use the Web. Based on an ethnographic study of a group of low-literate adults, we have identified specific navigational and content issues that present barriers to this population. We discuss preliminary assumptions that can be used to inform the development of Web tools for this target audience, and directions for future applied research.  相似文献   
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