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OBJECTIVE: To describe investigation of a tightly clustered outbreak of invasive group A streptococcal (GAS) disease associated with a high mortality rate in a long-term care facility (LTCF). DESIGN: Cross-sectional carriage survey and epidemiologic investigation of LTCF resident and employee cohorts. SETTING: A 104-bed community LTCF between March 1 and April 7, 2004. PATIENTS: A cohort of LTCF residents with assigned beds at the time of the outbreak. INTERVENTIONS: Reinforcement of standard infection control measures and receipt of chemoprophylaxis by GAS carriers. RESULTS: Four confirmed and 2 probable GAS cases occurred between March 16 and April 1, 2004. Four case patients died. The final case occurred during the investigation, before the patient was determined to be a GAS carrier. No case occurred during the 6 months after the intervention. Disease was caused by type emm3 GAS; 16.5% of residents and 2.4% of employees carried the outbreak strain. Disease was clustered in 1 quadrant of the LTCF and associated with nonintact skin. GAS disease or carriage was associated with having frequent personal visitors. CONCLUSIONS: Widespread carriage of a virulent GAS strain likely resulted from inadequate infection control measures. Enhanced infection control and targeted prophylaxis for GAS carriers appeared to end the outbreak. In addition to employees, regular visitors to LTCFs should be trained in hand hygiene and infection control because of the potential for extended relationships over time, leading to interaction with multiple residents, and disease transmission in such residential settings. Specific attention to prevention of skin breaks and proper wound care may prevent disease. The occurrence of a sixth case during the investigation suggests urgency in addressing severe, large, or tightly clustered outbreaks of GAS infection in LTCFs.  相似文献   
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A population-based study on 1008 postmenopausal women identified that the 24% of women achieving high levels of PA and CI had 3.4-4.4% higher femoral bone strength in axial compression and 1.7-5.2% in bending than those achieving low levels, indicating that lifestyle factors influence bone strength in the proximal femur. INTRODUCTION: Extensive research has shown that increased physical activity (PA) and calcium intake (CI) decrease the rate of bone loss; however, there is little research on how these lifestyle variables affect bone geometry. This study was designed to investigate the effects of modifiable lifestyle variables, habitual PA and dietary CI, on femoral geometry in older women. MATERIALS AND METHODS: Femoral geometry, habitual PA, and dietary CI were measured in a population-based sample of 1008 women (median age+/-interquartile range, 75+/-4years) enrolled in a randomized controlled trial (RCT) of calcium supplementation. Baseline PA and CI were assessed by validated questionnaires, and 1-year DXA scans (Hologic 4500A) were analyzed using the hip structural analysis technique. Section modulus (Z), an index of bending strength, cross-sectional area (CSA), an index of axial compression strength, subperiosteal width (SPW), and centroid position, the position of the center of mass, were measured at the femoral neck (NN), intertrochanter (IT), and femoral shaft (FS) sites. These data were divided into tertiles of PA and CI, and the results were compared using analysis of covariance (ANCOVA), with corrections for age, height, weight, and treatment (calcium/placebo). RESULTS AND CONCLUSIONS: PA showed a significant dose-response effect on CSA all hip sites (p<0.03) and Z at the narrow neck and intertrochanter sites (p<0.02). For CI, there was a dose-response effect for centroid position at the intertrochanter (p=0.03). These effects were additive, such that the women (n=240) with PA in excess of 65.5 kcal/day and CI in excess of 1039 mg/day had significantly greater CSA (NN, 4.4%; IT, 4.3%; FS, 3.4%) and Z (NN, 3.9%; IT, 5.2%). These data show a favorable association between PA and aspects of bone structural geometry consistent with better bone strength. Association between CI and bone structure was only evident in 1 of 15 variables tested. However, there was evidence that there may be additive effects, whereby women with high levels of PA and CI in excess of 1039 mg/day had significantly greater CSA (NN, 0.4%; FS, 2.1%) and Z (IT, 3.0%) than women with high PA but low CI. These data show that current public health guidelines for PA and dietary CI are not inappropriate where bone structure is the health component of interest.  相似文献   
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Ischaemia-reperfusion injury (IRI) is of obvious relevance in situations where there is an interruption of blood supply to the gut, as in vascular surgery, or in the construction of free intestinal grafts. It is now appreciated that IRI also underlies the gut dysfunction that occurs in early shock, sepsis, and trauma. The events that occur during IRI are complex. However, recent advances in cellular biology have started to unravel these underlying processes. The aim of this review is to provide an outline of current knowledge on the mechanisms and consequences of IRI. Initially, IRI appears to be mediated by reactive oxygen metabolites and, at a later stage, by the priming and activation of polymorphonuclear neutrophils (PMN). Ischaemia-reperfusion injury can diminish the barrier function of the gut, and can promote an increase in the leakage of molecules (intestinal permeability) or the passage of microbes across the wall of the bowel (bacterial trans-location). Ischaemia-reperfusion injury to the gut can result in the generation of molecules that may also harm distant tissues.  相似文献   
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When children are ill enough to require admission to paediatric intensive care, parents may become distressed about their child's medical condition and this distress may be compounded by the unfamiliar nature of the highly technological environment Parents of children who are sick enough to warrant intubation are particularly likely to be exposed to a frightening array of technological equipment Seventy-one parents of intubated and non-intubated children completed the Parental Stressor Scale Paediatnc Intensive Care Unit (PSS PICU) Overall the findings suggest that parents were most distressed (a) by the painful procedures to which their children were subjected, (b) by the sights and sounds of the intensive care unit and (c) by their children's reactions to intensive care The behaviour of staff towards parents and the way that staff communicated with them caused the least distress When the levels of stress reported by parents of intubated children were compared with those reported by parents of non-intubated children, different patterns of stress were found Painful procedures were a source of greater stress to parents of intubated children whereas the behaviour of staff and the children's reactions to the intensive care experience caused greater stress to the parents of the non-intubated children In general the findings suggest that the needs of parents of non-intubated children are being overlooked, with staff focusing more of their attention on the parents of intubated children  相似文献   
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In a sample of 55 consecutive methadone maintenance admissions to our clinic, 42% were diagnosed with antisocial personality disorder (ASPD) using the National Institute of Mental Health Diagnostic Interview Schedule NIMH DIS. Individuals with ASPD exhibited greater risk for HIV infection as defined by more sexual contacts, needle use and equipment sharing. Data at 1 year follow-up were obtained on this group of patients. The objective was to compare the ASPD and non-ASPD groups with regards to demographics, drug abuse history, outcome and retention in treatment. There were no significant differences between the groups on any demographic or treatment outcome variables. Survival analysis indicated that there were no group differences in treatment retention. In conclusion, although there were no differences in treatment outcome between ASPD and non-ASPD groups it is possible that ASPD patients who drop out of treatment will be at higher risk for contracting and spreading HIV within the IV drug using population. These data also suggest that in this population the diagnosis of ASPD using primarily behavioral traits as measured in the NIMH-DIS-III, has little utility in predicting treatment outcome.  相似文献   
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Despite being constantly cited as a critical intervening variable in the recovery from alcohol problems, there is a paucity of literature on client motivation. This paper reviews the current literature which impacts on motivation and its importance in treatment and develops in a stepwise manner the revised expectancy/motivation hypothesis, tentatively explaining both motivation and denial as a natural process in behavioural change. Because of the revised expectancy/motivation hypothesis' distinctly defined stages which closely relate to the process of nursing and the qualitative and quantitative measurement it entails which the nursing process demands, it offers a particularly appropriate model for treatment within nurse practice.  相似文献   
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