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11.
Several lines of evidence indicate that there may be an inflammatory component to the pathology of Alzheimer's disease (AD), the major form of degenerative dementia in the elderly. Activity of inflammatory cells, and the elaboration of toxic molecules by such cells may be a significant factor in disease progression. In peripheral inflammatory states, the increased activity of matrix metalloproteinase (MMP) enzymes are a major cause of tissue breakdown and secondary damage in diseases such as rheumatoid arthritis. The activity of such enzymes in the normal or diseased central nervous system is, however, not well characterized. We have therefore determined the levels of MMP 1 (collagenase) in the normal human brain and in AD. MMP1 levels were relatively low though were significantly elevated by approximately 50% in AD in all cortical areas examined. Given the activity towards collagen of MMP1, it is possible that enhanced MMP1 activity in AD, may contribute to the blood-brain barrier dysfunction seen in AD. 相似文献
12.
The occupational risk to dental anesthesiologists of acquiring 3 bloodborne pathogens 总被引:1,自引:0,他引:1 下载免费PDF全文
OBJECTIVE: To estimate the occupational risk to dental anesthesiologists of contracting 3 bloodborne pathogens: hepatitis B (HBV), hepatitis C (HCV), and human immunodeficiency virus (HIV). METHODS: Through an anonymously returned, mailed questionnaire, dental anesthesiologists in Canada and the United States provided information regarding percutaneous and mucocutaneous contacts with contaminated fluid during the treatment of patients under deep sedation and general anesthesia as well as other general practice information. A mathematical model was applied to determine the occupational risk. RESULTS: Of the 101 (65%) returned questionnaires, 98 reported having treated patients within the previous 6 months. Of these, 41 (42%) had at least one percutaneous accident (89 accidents in total), and the projected mean annual injury rate for dental anesthesiologists overall was 1.82. The most common causes of injury were burs, intraoral needles, and dental instruments. Operator error during use was associated with 31% of reported accidents. Significantly more injuries were reported by those who also reported a mucocutaneous contact and by those working more than 25 hours per week. The projected mean annual number of mucocutaneous exposures was 0.88 for dental anesthesiologists overall. CONCLUSIONS: The calculated annual risk to the average dental anesthesiologist of acquiring HBV (if not immune), HCV, and HIV following percutaneous injury was very low for all infections (HBV the most; HIV the least). The risk of contracting HIV following mucocutaneous contact was extremely low. 相似文献
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BD White A Kong E Khoo AM Southcott 《Journal of Medical Imaging and Radiation Oncology》2005,49(4):319-321
Tracheobronchopathia osteochondroplastica (TO) is a rare benign disease characterized by the presence of osseous and cartilaginous submucosal nodules projecting into the tracheobronchial tree. Most cases are asymptomatic and discovered incidentally at post‐mortem. We identified a case of TO on thoracic spiral CT and confirmed the diagnosis on bronchoscopy. This article reviews the imaging characteristics of TO, and shows the 3‐D virtual bronchoscopic and multiplanar reconstruction appearances of TO. 相似文献
14.
WBG Macdonald AP Patrikeos RI Thompson BD Adler AA Van Der Schaaf 《Journal of Medical Imaging and Radiation Oncology》2005,49(1):32-38
The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses. 相似文献
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kevern p. (2012) Journal of Nursing Management 20, 981–989
Who can give ‘spiritual care’? The management of spiritually sensitive interactions between nurses and patients Aims This article considers the purpose of contemporary ‘spiritual care’ in order to help managers make informed decisions about its appropriate delivery in a clinical context. Background Although there are national policies in place concerning spiritual care, surveys indicate that nurses are reluctant to engage with the spiritual needs of patients. Evaluation A consideration of the character of spiritual care indicates the need to take account of the context of contemporary Western society. A model drawn from the social psychology of religion is used to analyse the different types of nurse–patient interaction available in the provision of spiritual care. Key Issues Although religious and spiritual commitments can vary widely, they are subject to the same pressures in a secular and pluralist social context. This enables some general guidelines to be developed. Conclusions Effective spiritual care requires a consideration of both the patient’s and the nurse’s implicit and explicit religious commitments. Implications for nursing management Nurse managers need to take account of the personal commitments of nurses when directing them to offer spiritual care. This article offers a diagnostic tool for deploying nurses in an appropriate way. 相似文献
Who can give ‘spiritual care’? The management of spiritually sensitive interactions between nurses and patients Aims This article considers the purpose of contemporary ‘spiritual care’ in order to help managers make informed decisions about its appropriate delivery in a clinical context. Background Although there are national policies in place concerning spiritual care, surveys indicate that nurses are reluctant to engage with the spiritual needs of patients. Evaluation A consideration of the character of spiritual care indicates the need to take account of the context of contemporary Western society. A model drawn from the social psychology of religion is used to analyse the different types of nurse–patient interaction available in the provision of spiritual care. Key Issues Although religious and spiritual commitments can vary widely, they are subject to the same pressures in a secular and pluralist social context. This enables some general guidelines to be developed. Conclusions Effective spiritual care requires a consideration of both the patient’s and the nurse’s implicit and explicit religious commitments. Implications for nursing management Nurse managers need to take account of the personal commitments of nurses when directing them to offer spiritual care. This article offers a diagnostic tool for deploying nurses in an appropriate way. 相似文献
20.
Cytogenetic and histologic correlations in malignant lymphoma 总被引:9,自引:0,他引:9
Koduru PR; Filippa DA; Richardson ME; Jhanwar SC; Chaganti SR; Koziner B; Clarkson BD; Lieberman PH; Chaganti RS 《Blood》1987,69(1):97-102
Although a number of studies have indicated correlations between histologic subtypes of tumors and certain nonrandom chromosome changes, cytogenetic studies of lymphoma are in an early stage compared to those of leukemia. No comprehensive analysis of available data has so far been attempted in the literature either. Here we present an analysis of chromosome changes and their correlation with subtypes of lymphoma studied by conventional histology and cell surface markers, as observed in two sets of data: a group of 65 karyotypically abnormal tumors sequentially ascertained and studied by us during the period January 1, 1984 to April 30, 1985, and a larger data set derived by combining our data with those from two published series from the University of Minnesota that are comparable to our data. These combined data, which comprise the largest data set on the cytogenetics of lymphomas assembled so far, enabled a comprehensive analysis of correlation between chromosome change and tumor histology and the patterns of chromosome instability in these tumors. We found several significant associations, some previously described and others now recognized, between nonrandom chromosome gains, breaks, translocations, and deletions and histologic subtypes of tumors that characterize lymphomas. The data indicate that finding of chromosome breaks at certain sites (eg, 8q24, 14q32, 18q21) is of diagnostic value in dealing with cases of unusual lymphoma. Furthermore, nonrandom chromosome breakage exhibited three distinct patterns that reflected three levels of etiologically relevant genetic change. 相似文献