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We describe the clinical and pathological findings of the hemolytic uremic syndrome (HUS) in two children with human immunodeficiency virus (HIV) infection. Both patients presented with microangiopathic hemolytic anemia, thrombocytopenia, and subsequently developed renal failure. The diagnosis of HUS was confirmed by renal histopathology in both patients. None of these children presented with bloody diarrhea, evidence of circulating antibody response to Escherichia coli O157 lipopolysaccharide, or other known risk factors for HUS, except for the presence of HIV infection. Each patient was treated with intravenous plasma infusion and renal replacement therapy. Their clinical course was characterized by non-oliguria and lack of significant hypertension throughout the acute phase of the disease. Despite these favorable clinical parameters, both patients developed end-stage renal failure. The etiology of this atypical HUS characterized by poor renal survival remains unknown and the role of HIV infection in its pathogenesis, although possible, is unclear. Received March 5, 1996; received in revised form and accepted October 15, 1996  相似文献   
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Abstract Home visiting is a central, long-standing, and yet theoretically underdeveloped public health nursing process. The general aim of this study was to expand and refine a preliminary model of home visiting A stylized field research investigation was conducted in the area of maternal-child health with one nurse in a visiting nurse association in New England. A specific type of home visiting, identified as child focused, emerged, with phases labeled as surveying and designating; selling and scheduling; approaching the home and the visit; entering the home; gaining permission to ask questions and access the infant—starting with the mother's expressed concerns; making the caregiving judgment—asking questions and weighing and examining the infant; and ending the visit. "Haunting and telling" was an additional phase for certain visits. The nurse conducted child-focused home visiting in three patterns. The single pattern is described in this article. Potential maternal, child, interactive, and environmental consequences were identified, as were factors influencing the process of maternal-child home visiting. Social exchange theory emerged as useful in describing how the nurse initiated, maintained, and ended the home visiting process, and in describing attendant client consequences.  相似文献   
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This paper concerns the analysis of menstrual data; in particular, methodology to identify variables that contribute to the variability of menstrual cycles both within and between women. The basis for the proposed methodology is a parameterization of the mean length of a menstrual cycle conditional upon the past cycles and covariates. This approach accommodates the length-bias and censoring commonly found in menstrual data. Data from a longitudinal study of menstrual patterns and other variables among Lese women of the Ituri Forest, Zaire, illustrate the methodology. A small simulation illustrates the bias caused by incorrectly deleting the censored cycles.  相似文献   
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Two children who presented with fever, rash, and hypotension were found to have group A beta hemolytic streptococcal toxic shock syndrome. These cases are reported to remind physicians who care for acutely ill children that exotoxin-producing streptococci can produce clinical features and multisystem failure similar to staphylococcal toxic shock syndrome.  相似文献   
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Very little is known regarding the mechanisms of action of angiotensin II (Ang II) or the consequences of Ang II-dependent hypertension in the cerebral circulation. We tested the hypothesis that Ang II produces constriction of cerebral arteries that is mediated by activation of AT1A receptors and Rho-kinase. Basilar arteries (baseline diameter approximately 130 microm) from mice were isolated, cannulated and pressurized to measure the vessel diameter. Angiotensin II was a potent constrictor in arteries from male, but not female, mice. Vasoconstriction in response to Ang II was prevented by an inhibitor of Rho-kinase (Y-27632) in control mice, and was reduced by approximately 85% in mice deficient in expression of AT1A receptors. We also examined the chronic effects of Ang II using a model of Ang II-dependent hypertension, mice which overexpress human renin (R+) and angiotensinogen (A+). Responses to the endothelium-dependent agonist acetylcholine were markedly impaired in R+A+ mice (P<0.01) compared with controls, but were restored to normal by a superoxide scavenger (PEG-SOD). A-23187 (another endothelium-dependent agonist) produced vasodilation in control mice, but no response or vasoconstriction in R+A+ mice. In contrast, dilation of the basilar artery in response to a NO donor (NONOate) was similar in R+A+ mice and controls. Thus, Ang II produces potent constriction of cerebral arteries via activation of AT1A receptors and Rho-kinase. There are marked gender differences in cerebral vascular responses to Ang II. Endothelial function is greatly impaired in a genetic model of Ang II-dependent hypertension via a mechanism that involves superoxide.  相似文献   
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BACKGROUND: Quality of life has increased in popularity as an outcome measure in health research. However, the measurement of quality of life has been questioned on methodologic grounds, as it often shows little association with objective measures of disease status. OBJECTIVE: For this report we studied the determinants of pediatric asthma caregiver report of quality of life and its relationship to disease burden. METHOD: Ninety-eight children who were admitted to a Pediatric Day Program for an asthma evaluation were enrolled in an outcome study. A complete set of medical records for the 2-year period before and after the admission was collected and systematically coded for health care utilization. Using the Pediatric Asthma Caregiver's Quality of Life Questionnaire, data were collected at baseline, discharge, and year after the admission. Caregiver negative affect (anxiety and depression), measured with the Brief Symptom Inventory, was also collected at baseline and discharge. RESULTS: Caregiver report of quality of life was unrelated to health care utilization at baseline but instead was significantly related to baseline caregiver negative affect. A significant relationship between health care utilization and quality of life was present at followup. The Emotional Function scale from the quality of life measure can account for most of the relationship between quality of life and negative affect. CONCLUSIONS: Caregiver affect may have a considerable influence on report of quality of life. Understanding the individual characteristics of the respondent is important when using a quality of life instrument as an outcome measure.  相似文献   
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