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81.
Geert R. Mortier Ralph S. Lachman Maureen Bocian David L. Rimoin 《American journal of medical genetics. Part A》1996,61(4):310-319
To further delineate and classify those forms of short trunk dwarfism characterized by multiple vertebral segmentation defects, we analyzed 26 new patients and reviewed 115 described in the literature. Three distinct entities were recognized based on radio-graphic and clinical findings. Jarcho-Levin syndrome is the lethal autosomal recessive form, characterized by a symmetric crablike chest. Spondylocostal dysostosis is the benign autosomal dominant condition. Spondylothoracic dysostosis shows considerable clinical and radiographic overlap with spondylocostal dysostosis. Malformations observed in association with multiple vertebral segmentation defects are more common in the sporadic patients. Analysis of the 26 new individuals revealed that the body segment in which these nonvertebral malformations occur corresponds to the site of the vertebral segmentation defects. © 1996 Wiley-Liss, Inc. 相似文献
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Johannes Kolck Katharina Ziegeler Thula Walter-Rittel Kay Geert A. Hermann Bernd Hamm Alexander Beck 《The British journal of radiology》2022,95(1130)
Objectives:Radiography remains the mainstay of diagnostic and follow-up imaging. In view of the risks and the increasing use of ionizing radiation, dose reduction is a key issue for research and development. The introduction of digital radiography and the associated access to image postprocessing have opened up new opportunities to minimize the radiation dosage. These advances are contingent upon quality controls to ensure adequate image detail and maintenance of diagnostic confidence. The purpose of this study was to investigate the clinical applicability of postprocessed low-dose images in skeletal radiography.Methods:In our study setting, the median radiation dose for full dose X-rays was 9.61 dGy*cm2 for pelvis, 1.20 dGy*cm2 for shoulder and 18.64 dGy*cm2 for lumbar spine exams. Based on these values, we obtained 200 radiographs for each anatomic region in four consecutive steps, gradually reducing the dose to 84%, 71%, 60% and 50% of the baseline using an automatic exposure control (AEC). 549 patients were enrolled for a total of 600 images. All X-rays were postprocessed with a spatial noise reduction algorithm. Two radiologists assessed the diagnostic value of the radiographs by rating the visualization of anatomical landmarks and image elements on a five-point Likert scale. A mean-sum score was calculated by averaging the two reader’s total scores. Given the non-parametric distribution, we used the Mann-Whitney U test to evaluate the scores.Results:Median dosage at full dose accounted for 38.4%, 48 and 53.2% of the German reference dose area product for shoulder, pelvis and lumbar spine, respectively. The applied radiation was incrementally reduced to 21.5%, 18.4% and 18.7% of the respective reference value for shoulder, pelvis and lumbar spine. Throughout the study, we observed an estimable tendency of superior quality at higher dosage in overall image quality. Statistically significant differences in image quality were restricted to the 50% dose groups in shoulder and lumbar spine images. Regardless of the applied dosage, 598 out of 600 images were of sufficient diagnostic value.Conclusion:In digital radiography image postprocessing allows for extensive reduction of radiation dosage. Despite a trend of superior image detail at higher dose levels, overall quality and, more importantly, diagnostic utility of low-dose images was not significantly affected. Therefore, our results not only confirm the clinical utility of postprocessed low-dose radiographs, but also suggest a widespread deployment of this advanced technology to ensure further dose limitations in clinical practice.Advances in knowledge:The diagnostic image quality of postprocessed skeletal radiographs is not significantly impaired even after extensive dose reduction by up to 20% of the reference value. 相似文献
84.
Geert Molenberghs Christel Faes Johan Verbeeck Patrick Deboosere Steven Abrams Lander Willem Jan Aerts Heidi Theeten Brecht Devleesschauwer Natalia Bustos Sierra Franoise Renard Sereina Herzog Patrick Lusyne Johan Van der Heyden Herman Van Oyen Pierre Van Damme Niel Hens 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(7)
BackgroundCOVID-19 mortality, excess mortality, deaths per million population (DPM), infection fatality ratio (IFR) and case fatality ratio (CFR) are reported and compared for many countries globally. These measures may appear objective, however, they should be interpreted with caution.AimWe examined reported COVID-19-related mortality in Belgium from 9 March 2020 to 28 June 2020, placing it against the background of excess mortality and compared the DPM and IFR between countries and within subgroups.MethodsThe relation between COVID-19-related mortality and excess mortality was evaluated by comparing COVID-19 mortality and the difference between observed and weekly average predictions of all-cause mortality. DPM were evaluated using demographic data of the Belgian population. The number of infections was estimated by a stochastic compartmental model. The IFR was estimated using a delay distribution between infection and death.ResultsIn the study period, 9,621 COVID-19-related deaths were reported, which is close to the excess mortality estimated using weekly averages (8,985 deaths). This translates to 837 DPM and an IFR of 1.5% in the general population. Both DPM and IFR increase with age and are substantially larger in the nursing home population.DiscussionDuring the first pandemic wave, Belgium had no discrepancy between COVID-19-related mortality and excess mortality. In light of this close agreement, it is useful to consider the DPM and IFR, which are both age, sex, and nursing home population-dependent. Comparison of COVID-19 mortality between countries should rather be based on excess mortality than on COVID-19-related mortality. 相似文献
85.
Astrid Versluis ThuyMy Le Francine C. van Erp Mark A. Blankestijn Geert F. Houben Andr C. Knulst Harmieke van Os Medendorp 《Clinical and translational allergy》2022,12(2)
BackgroundAfter a positive food challenge (FC), patients receive dietary advice regarding avoidance of the culprit food. We examined the frequency and variables associated with dietary adherence after a positive FC in adults.MethodsIn this prospective daily practice study, adults with a positive FC were included. After every FC, dietary advice was given consisting of three options: (1) strict avoidance, (2) avoidance but products with precautionary allergen labelling (PAL) allowed and (3) (small) amounts allowed. Questionnaires about dietary adherence and associated variables were completed prior to and 6 months after the FC(s).Results41 patients (with 58 positive FCs) were included. Overall, patients adhered to the advised diet after 31% of the FCs. After 33 FCs, the advice was strict avoidance, whereof 82% followed a less strict diet. After 16 FCs, the advice was avoidance but products with PAL allowed, whereof 19% followed a less strict and 25% a stricter diet. In 9 FCs with the least strict advice, “(small) amounts allowed’’, 67% followed a stricter diet. Three variables were associated with adherence: misremembering dietary advice, impaired health‐related quality of life (HRQL) on domain “Emotional impact’’ and the need for dietary change after the FC.ConclusionAfter one third of the positive FCs, patients adhered to the dietary advice. Variables associated with adherence were misremembering dietary advice, impaired HRQL on domain “Emotional impact’’ and the need for dietary change after the FC. It seems important that healthcare professionals should more frequently apply adherence‐enhancing strategies to improve dietary adherence. 相似文献
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Verbruggen Lisanne C. Hudson Melissa M. Bowers Daniel C. Ronckers Cécile M. Armstrong Gregory T. Skinner Roderick Hoving Eelco W. Janssens Geert O. van der Pal Helena J. H. Kremer Leontine C. M. Mulder Renée L. 《Journal of neuro-oncology》2020,147(2):417-425
Journal of Neuro-Oncology - Childhood, adolescent and young adult (CAYA) cancer survivors treated with cranial radiotherapy are at risk for developing subsequent meningiomas. There is insufficient... 相似文献
88.
Linda A. Schoo Martine J. E. van Zandvoort Yael D. Reijmer Geert Jan Biessels L. Jaap Kappelle Albert Postma 《Journal of clinical and experimental neuropsychology》2014,36(6):648-658
Reconstructing the temporal order of events is a crucial part of episodic memory. The temporal dimension, however, is often discarded in clinical settings, and measurements of true temporal aspects of episodic memory are scarce. The present study assessed temporal memory in stroke patients and in age- and education-matched healthy controls. Both groups underwent a standardized neuropsychological examination. We asked participants afterwards to reconstruct the order of tests they had performed, measured in absolute temporal order (event placed on correct moment in sequence) and relative temporal order (event placed correctly relative to directly preceding and following events). The aim of the study was to examine how serial-position curve effects (measuring absolute temporal order anchored in exact time) and how relative temporal order memory (anchored to other events) may differ in a group of cerebral stroke patients. Another aim was to link temporal order memory deficits with established neuropsychological measures of cognitive functioning. Although item identification was comparable in both groups, absolute temporal order memory was impaired in patients: A total of 43% of the patients lacked the expected primacy and recency effects (serial position effect). In addition, relative temporal order memory was affected in this group as well, F(1, 70) = 4.08, p < .05; 25% of the patients were impaired in reconstructing the relative temporal order (p = .019, Fisher’s Exact Test). Both absolute and relative temporal order memory performance related to the domains of executive functioning and memory. Our results suggest that it is important to test both absolute and relative temporal order memory, especially because these types of memory depend on different anchors, either on time or on adjacent events. 相似文献
89.