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The present communication broadens the data base for determinations of the non-reference condition correction factor kNR needed in high-energy photon dosimetry to accomplish the use of various detectors under non-reference conditions. Following our previous strategy of calculating semiempirical values of kNR and correlating them with the mean photon energy Em at the point of measurement in a large water phantom, the values of Em are now stated for 6 and 15 MV photon radiations of accelerators with and without flattening filters, square field sizes from 1 to 30 cm side length and depths from 0 to 28 cm. The unambiguity of the kNR-Em correlation is again confirmed and is quantified by fitting formulae for air-filled ionization chambers, TLD detectors and Si diodes. This survey provides a practicable access to the kNR values, particularly for the non-water equivalent detectors to be used in small-field dosimetry 相似文献
104.
Michael C. Seidenbusch Dietrich Harder Dieter F. Regulla Karl Schneider 《Zeitschrift für medizinische Physik》2014,24(2):123-137
Estimations of organ doses DT received during computed tomographic examinations are usually performed by applying conversion factors to basic dose indicators like the computed tomography dose index (CTDI) or the dose-length-product (DLP). In addition to the existing conversion factors for beam apertures of 5 mm or 10 mm, we present new DLP-DT conversion factors adapted to high-resolution CT (HRCT) examinations of infants and young children with beam apertures of the order of 1 mm and under consideration of bow tie filtration. Calculations are performed on mathematical MIRD phantoms for an age range from 0, 1, 5, 10, 15 up to (for comparison) 30 years by adapting PCXMC, a Monte Carlo algorithm originally developed by STUK (Helsinki, Finland) for dose reconstructions in projection radiography. For this purpose, each single slice CT examination is approximated by a series of corresponding virtual planar radiographies comprising all focus positions. The transformation of CT exposure parameters into exposure parameters of the series of corresponding planar radiographies is performed by a specially developed algorithm called XCT. The DLP values are evaluated using the EGSRay code. The new method is verified at a beam aperture of 10 mm by comparison with formerly published conversion factors. We show that the higher spatial resolution leads to an enhanced DLP-DT conversion factor if a small organ (e. g. thyroid gland, mammae, uterus, ovaries, testes) is exactly met by the chosen CT slice, while the conversion factor is drastically reduced if the chosen CT slice is positioned above or below the organ. This effect is utilized for dose-saving examinations with only a few single slices instead a full scan, which technique is applied in about 10% of all paediatric chest CT examinations. 相似文献
105.
Trauma und Berufskrankheit - Die ABMR ist ein neues Modul im Heilverfahren der gesetzlichen Unfallversicherung. Sie soll zu dessen Abschluss insbesondere bei schwer körperlich Tätigen die... 相似文献
106.
Claudia Schulz Gisela Büchele Martin Rehm Dietrich Rothenbacher Patrick Roigk Kilian Rapp Christian Günster Hans-Helmut König Katrin Reber 《Journal of the American Medical Directors Association》2019,20(4):451-455.e3
Objectives
Hip fractures are common consequences of falls in older adults and, among other negative health outcomes, often lead to care dependence in the long term. Until 2016, the German long-term care insurance classified care recipients according to a standardized classification system consisting of 3 care levels. It was based on required assistance in performing activities of daily living and assessed by a qualified physician or nurse. Thus, care level reflects the degree of care dependence. The aim of this study was to determine relevant patient characteristics, which are related to the likelihood of increasing care dependence in terms of worsening care level after hip fracture.Design
Retrospective cohort study.Setting and participants
Statutory health insurance claims data including 122,922 insured individuals living in Germany and aged 65 years or older, who sustained a hip fracture from 2009 through 2011.Measures
The association of patient characteristics with worsening care level in the quarterly period after hip fracture was investigated by means of multinomial logit regression analysis. Death constitutes a competing risk and was modeled as additional nominal outcome.Results
Among all patients, crude rates were 30.9% for worsening care level, 54.8% for unchanged care level, and 14.4% for death after hip fracture. The multivariate analysis revealed that patient factors male sex, increasing age, increasing comorbidity, increasing inpatient length of stay, and a lack of inpatient rehabilitation were significantly associated with a worsening care level.Conclusions/Implications
This study uses the German standardized measurement of care dependence in terms of worsening care level after hip fracture and finds various related patient characteristics. Knowledge of these characteristics helps to identify possible risk groups for care dependence after hip fracture, for which special attention can be provided regarding treatment and prevention of hip fractures. 相似文献107.
Christoph F. Dietrich Adrian Goudie Liliana Chiorean Xin Wu Cui Odd Helge Gilja Yi Dong Jacques S. Abramowicz Sudhir Vinayak Susan Campbell Westerway Christian Pállson Nolsøe Yi-Hong Chou Michael Blaivas 《Ultrasound in medicine & biology》2017,43(1):49-58
Over the last decade, the use of portable ultrasound scanners has enhanced the concept of point of care ultrasound (PoC-US), namely, “ultrasound performed at the bedside and interpreted directly by the treating clinician.” PoC-US is not a replacement for comprehensive ultrasound, but rather allows physicians immediate access to clinical imaging for rapid and direct solutions. PoC-US has already revolutionized everyday clinical practice, and it is believed that it will dramatically change how ultrasound is applied in daily practice. However, its use and teaching are different from continent to continent and from country to country. This World Federation for Ultrasound in Medicine and Biology position paper discusses the current status and future perspectives of PoC-US. Particular attention is given to the different uses of PoC-US and its clinical significance, including within emergency and critical care medicine, cardiology, anesthesiology, rheumatology, obstetrics, neonatology, gynecology, gastroenterology and many other applications. In the future, PoC-US will be more diverse than ever and be included in medical student training. 相似文献
108.
Marina Díaz-Beyá Myriam Labopin Johan Maertens Mahmoud Alijurf Jakob Passweg Beelen Dietrich Harry Schouten Gerard Socié Nicolaas Schaap Rainer Schwerdtfeger Liisa Volin Mauricette Michallet Emmanuelle Polge Jorge Sierra Mohamad Mohty Jordi Esteve Arnon Nagler the Acute Leukaemia Working Party of the European Society for Blood Marrow Transplantation 《British journal of haematology》2020,189(5):920-925
Acute myeloid leukaemia (AML) with t(6;9)(p23;q34) is a poor-risk entity, commonly associated with FLT3-ITD (internal tandem duplication). Allogeneic stem-cell tranplantation (allo-SCT) is recommended, although studies analysing the outcome of allo-SCT in this setting are lacking. We selected 195 patients with t(6;9) AML, who received a first allo-SCT between 2000 and 2016 from the EBMT (European Society for Blood and Marrow Transplantation) registry. Disease status at time of allo-SCT was the strongest independent prognostic factor, with a two-year leukaemia-free survival and relapse incidence of 57% and 19% in patients in CR1 (first complete remission), 34% and 33% in CR2 (second complete remission), and 24% and 49% in patients not in remission, respectively (P < 0·001). This study, which represents the largest one available in t(6;9) AML, supports the recommendation to submit these patients to allo-SCT in CR1. 相似文献
109.
Bernard Barhafumwa Janan Dietrich Kalysha Closson Hasina Samji Angela Cescon Busisiwe Nkala 《Vulnerable children and youth studies》2016,11(3):263-273
Adolescents in HIV endemic settings are a priority demographic with respect to HIV prevention. Some studies have shown that behaviours associated with HIV transmission, may be mediated by mental health factors such as depression. We undertook this study to explore the prevalence and associations of depression symptomology among adolescents living in the HIV endemic community of Soweto, South Africa through the Botsha Bophelo Adolescent Health Study (BBAHS). We estimated the prevalence of depression using the Centre for Epidemiological Studies of Depression Scale, using a score of ≥24 to indicate ‘probable depression’. Among the 789 adolescents (14–19 years) with depression scores, 262 (33%) met the criteria for probable depression (99 [38%] men and 163 [62%] women; p = 0.061). In multivariable logistic regression, factors independently associated with depression included being female (AOR = 2.44, 95% CI: 1.45–4.00), marijuana use (AOR = 2.67, 95% CI: 1.21–5.93), physical violence (AOR = 1.63, 95% CI: 1.01–2.62), pregnancy (AOR = 2.00, 95% CI: 1.03–3.88) and incarceration (AOR = 2.09, 95% CI: 0.99–4.42). These data indicate that a concerning proportion of adolescents in Soweto may be suffering from depression and those screened as potentially depressed, were more likely to be female and have cofactors relating to increased risk for HIV. As part of a comprehensive HIV prevention strategy, we recommend that depression screening for adolescents be integrated into public and school health programs that triage those suffering into treatment programs. 相似文献
110.
Factors Associated with Reported Infection and Lymphedema Symptoms among Individuals with Extremity Lymphedema 下载免费PDF全文
Jie Deng PhD RN OCN Mei R. Fu PhD RN APRN‐BC FAAN Jane M. Armer PhD RN FAAN Janice N. Cormier MD MPH M. Elise Radina PhD CFLE Saskia R.J. Thiadens RN Jan Weiss PT DHS CLT‐LANA Catherine M. Tuppo PT MS CLT‐LANA Mary S. Dietrich PhD Sheila H. Ridner PhD RN FAAN 《Rehabilitation nursing》2015,40(5):310-319