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排序方式: 共有522条查询结果,搜索用时 31 毫秒
81.
Deep vein thrombosis and pulmonary embolism, the common clinical manifestations of venous thromboembolism (VTE), are among the most preventable complications of hospitalized patients. However, survey data repeatedly show poor rates of compliance with guideline-based preventive strategies. This has led the Centers for Medicare and Medicaid Services to deny reimbursement for hospital readmission for thromboembolic complications in patients undergoing total hip or knee arthroplasty. Multiple strategies and national initiatives have been developed to improve rates of VTE prophylaxis during hospitalization; however, most VTE occurs in the outpatient setting. Epidemiologic data suggest that recent surgery or hospitalization is a strong risk factor for the development of VTE and that this risk may persist for up to 6 months. These observations call into question whether VTE prophylaxis should be administered only during hospitalization or if this preventive strategy should be continued after hospital discharge. Many of the randomized trials showing efficacy of VTE prophylaxis have used longer durations of prophylaxis than are typical for current length of hospital stay, highlighting the issue of how long the duration of prophylaxis should be. Several patient groups have undergone formal testing to evaluate the risks and benefits of extended-duration VTE prophylaxis, but this issue is less clear for other categories of patients. Although there is clear consensus that most hospitalized patients should receive VTE prophylaxis, there is uncertainty about whether to continue VTE prophylaxis in the immediate post-hospital period or for an extended duration. The transition from inpatient to outpatient care is a key event in the coordination of continuity of care, but VTE-specific care transition guidance is limited. In this article, we review the evidence for both standard- and extended-duration VTE prophylaxis and discuss the difficulties in effectively maintaining VTE prophylaxis during the transition from inpatient to outpatient care. 相似文献
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Koehler MJ Hahn S Preller A Elsner P Ziemer M Bauer A König K Bückle R Fluhr JW Kaatz M 《Experimental dermatology》2008,17(6):519-523
Background: Morphological changes in the dermal collagen and elastin fibre network are characteristic for skin ageing and for pathological skin conditions of the dermis. Objectives: To characterize pathological and physiological conditions by multiphoton laser scanning tomography (MLT) in vivo, it is necessary to investigate and identify morphological alterations related to ageing. Methods: In vivo MLT was used to image two‐photon excited autofluorescence (AF) and second harmonics generation (SHG) in human dermis of 18 volunteers of different ages. Criteria for the evaluation of age‐dependent morphological changes in MLT images were fibre tension and morphology, network pattern, clot formation and image homogeneity. These criteria were weighted and a score was calculated. Results: The resulting MLT‐based Dermis Morphology Score is correlated with age (R2 = ?0.90) and with the previously published SHG to AF Ageing Index of Dermis (R2 = 0.66). The two groups of young (age 21–38) and old (age 66–84) volunteers showed a significant difference in MLT score values (P < 0.001). Conclusions: We could demonstrate an in vivo relationship between morphological characteristics of human dermis assessed by MLT and age. The present score allows the semi‐quantitative evaluation of specific morphological changes of the dermal fibre network in ageing skin by in vivo AF and SHG imaging. This method will be useful for diagnostics of pathological conditions and their differentiation from ageing effects. 相似文献
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LJ Bell L Oliver P Vial TN Eade M Rinks E Hammond GW Morgan M Back KL Wiltshire 《Journal of Medical Imaging and Radiation Oncology》2010,54(1):82-89
The aim of this paper is to detail the experience obtained in implementing an image-guided radiation therapy program at the Northern Sydney Cancer Centre. This required retrofitting a Varian Clinac 21EX with an on-board imager. The commissioning and quality assurance procedures, organisation of a multidisciplinary image guided radiation therapy group, and the development of clinical protocols for orthogonal kV and cone beam computed tomography implementation are described. Reassessment of the image-guided radiation therapy program has continued as new equipment and software versions were made available in the department. 相似文献
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Dr. M.J. Köhler S. Springer M. Kaatz 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》2014,65(9):814-822
Background
The volume of search engine queries about disease-relevant items reflects public interest and correlates with disease prevalence as proven by the example of flu (influenza). Other influences include media attention or holidays.Study goal
The present work investigates if the seasonality of prevalence or symptom severity of dermatoses correlates with search engine query data.Methods
The relative weekly volume of dermatological relevant search terms was assessed by the online tool Google Trends for the years 2009–2013. For each item, the degree of seasonality was calculated via frequency analysis and a geometric approach.Results
Many dermatoses show a marked seasonality, reflected by search engine query volumes. Unexpected seasonal variations of these queries suggest a perviously unknown variability of the respective disease prevalence. Furthermore, using the example of allergic rhinitis, a close correlation of search engine query data with actual pollen count can be demonstrated.Discussion
In many cases, search engine query data are appropriate to estimate seasonal variability in prevalence of common dermatoses. This finding may be useful for real-time analysis and formation of hypotheses concerning pathogenetic or symptom aggravating mechanisms and may thus contribute to improvement of diagnostics and prevention of skin diseases. 相似文献89.
Enrico Dimitrow Iris Riemann Alexander Ehlers Martin Johannes Koehler Johannes Norgauer Peter Elsner Karsten König Martin Kaatz 《Experimental dermatology》2009,18(6):509-515
Abstract: Multiphoton excited tissue fluorescence summarises the emission of all naturally occurring endogenous fluorescent bio-molecules with their often overlapping fluorescence spectra. Common fluorescence intensity measurements could not be utilised to distinguish between different fluorophores or metabolic states. To overcome this limitation, we investigated new procedures of selective melanin imaging and spectral fluorescence lifetime imaging in combination with high resolution multiphoton laser tomography. Overall 46 melanocytic lesions of human skin were analysed. We suggested that fluorescence light, detected in such a way, may yield additional information for melanoma diagnostics. Remarkable differences in lifetime behaviour of keratinocytes in contrast to melanocytes were observed. Fluorescence lifetime distribution was found in correlation with the intracellular amount of melanin. Spectral analysis of melanoma revealed a main fluorescence peak around 470 nm in combination with an additional peak close to 550 nm throughout all epidermal layers. Excitation at 800 nm shows a selectively observable fluorescence of melanin containing cells and offers the possibility of cell classification. Procedures of selective imaging as well as spectral fluorescence lifetime imaging by means of multiphoton laser tomography support diagnostic decisions and may improve the process of non-invasive early detection of melanoma. 相似文献
90.
CP Murray PM Wong J Louw GW Waterer 《Journal of Medical Imaging and Radiation Oncology》2009,53(4):339-344
To determine the prevalence of small lung nodules on low‐dose helical computed tomography (CT) in a Western Australian cohort of asymptomatic long‐term cigarette smokers and to compare this with a large, similarly derived cohort of North Americans from the Mayo Clinic Lung Cancer Screening Trial. Forty‐nine asymptomatic long‐term cigarette smokers of minimum age 50 years underwent a low‐dose 64‐slice helical CT of the lungs. Images were viewed on a soft copy reporting station with thin section axial and coronal images, maximum intensity projection images, and advanced image manipulation tools. The prevalence of all nodules was 39%, significantly lower than the Mayo Clinic cohort prevalence of 51% (P < 0.01, Fisher's exact test), despite the use of more advanced imaging technology and image manipulation designed to increase the sensitivity for nodules. The prevalence of small nodules in asymptomatic long‐term cigarette smokers in Western Australia is high, though significantly less than that found in a large study in North America. The authors postulate this is due to the relatively low rates of mycobacterium tuberculosis and soil‐derived fungal pulmonary infections in Western Australia, as well as a lower degree of urban air pollution. 相似文献