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排序方式: 共有248条查询结果,搜索用时 31 毫秒
1.
J?rn Wulf Ulrich H?dinger Ulrich Oppitz Wibke Thiele Michael Flentje 《Radiotherapy and oncology》2003,66(2):141-150
BACKGROUND AND PURPOSE: Previous analyses of target reproducibility in extracranial stereotactic radiotherapy have revealed standard security margins for planning target volume (PTV) definition of 5mm in axial and 5-10mm in longitudinal direction. In this study the reproducibility of the clinical target volume (CTV) of lung and liver tumors within the PTV over the complete course of hypofractionated treatment is evaluated. The impact of target mobility on dose to the CTV is assessed by dose-volume histograms (DVH). MATERIALS AND METHODS: Twenty-two pulmonary and 21 hepatic targets were treated with three stereotactic fractions of 10 Gy to the PTV-enclosing 100%-isodose with normalization to 150% at the isocenter. A conformal dose distribution was related to the PTV, which was defined by margins of 5-10mm added to the CTV. Prior to each fraction a computed tomography (CT)-simulation over the complete target volume was performed resulting in a total of 60 CT-simulations for lung and 58 CT-simulations for hepatic targets. The CTV from each CT-simulation was segmented and matched with the CT-study used for treatment planning. A DVH of the simulated CTV was calculated for each fraction. The target coverage (TC) of dose to the simulated CTV was defined as the proportion of the CTV receiving at least the reference dose (100%). RESULTS: A decrease of TC to <95% was found in 3/60 simulations (5%) of pulmonary and 7/58 simulations (12%) of hepatic targets. In two of 22 pulmonary targets (9%) and in four of 21 hepatic targets (19%) a TC of <95% occurred in at least one fraction. At risk for a decreased TC <95% were pulmonary targets with increased breathing mobility and hepatic targets with a CTV exceeding 100 cm(3). CONCLUSIONS: Target reproducibility was precise within the reference isodose in 91% of lung and 81% of liver tumors with a TC of the complete CTV >or=95% at each fraction of treatment. Pulmonary targets with increased breathing mobility and liver tumors >100 cm(3) are at risk for target deviation exceeding the standard security margins for PTV-definition at least for one fraction and require individual evaluation of sufficient margins. 相似文献
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Michael Zech MD Robert Jech MD PhD Sylvia Boesch MD Matej Škorvánek MD PhD Ján Necpál MD Jana Švantnerová MD Matias Wagner MD Ariane Sadr-Nabavi PhD Felix Distelmaier MD Martin Krenn MD PhD Tereza Serranová MD PhD Irena Rektorová MD PhD Petra Havránková MD PhD Alexandra Mosejová MD Iva Příhodová MD PhD Jana Šarláková MD Kristína Kulcsarová MD Olga Ulmanová MD PhD Karel Bechyně MD Miriam Ostrozovičová MD Vladimír Haň MD PhD Joaquim Ribeiro Ventosa MD Theresa Brunet MD Riccardo Berutti PhD Mohammad Shariati MD Ali Shoeibi MD Susanne A. Schneider MD Alice Kuster MD Matthias Baumann MD David Weise MD Friederike Wilbert MD Wibke G. Janzarik MD Matthias Eckenweiler MD Volker Mall MD Bernhard Haslinger MD Steffen Berweck MD Juliane Winkelmann MD Konrad Oexle MD 《Movement disorders》2021,36(8):1959-1964
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Gastric perception thresholds are low and sensory neuropeptide levels high in helicobacter pylori-positive functional dyspepsia 总被引:7,自引:0,他引:7
Mönnikes H van der Voort IR Wollenberg B Heymann-Monnikes I Tebbe JJ Alt W Arnold R Klapp BF Wiedenmann B McGregor GP 《Digestion》2005,71(2):111-123
BACKGROUND AND AIMS: In functional dyspepsia (FD) decreased perception levels can be shown on gastric distension. Substance P (SP) and calcitonin gene-related peptide (CGRP) are involved in the sensitization of afferent neuronal pathways due to chronic inflammation. The role of Helicobacter pylori-induced gastric mucosal inflammation in the pathogenesis of FD is controversial. The aim of this study was to assess whether FD patients have altered mucosal concentrations of CGRP and SP, and to investigate whether this is associated with visceral hypersensitivity or H. pylori infection. METHODS: Gastrointestinal symptoms, H. pylori status, perception thresholds at gastric balloon distension, and gastric mucosal concentrations of CGRP and SP were determined in 13 FD patients and 18 healthy controls (HC). RESULTS: In H. pylori-positive FD patients discomfort and pain thresholds on gastric distension were lower compared to other groups. Antral mucosal levels of CGRP and SP were higher in H. pylori-positive subjects. In FD significantly negative correlations between discomfort and pain thresholds and antral mucosal concentrations of CGRP and SP were observed. CONCLUSIONS: In FD low perception thresholds on gastric distension are associated with high levels of CGRP and SP in the antrum, suggesting that sensory neuropeptides are involved in FD pathophysiology. 相似文献
6.
Melanie Boerries Florian Grahammer Sven Eiselein Moritz Buck Charlotte Meyer Markus Goedel Wibke Bechtel Stefan Zschiedrich Dietmar Pfeifer Denis Laloë Christelle Arrondel Sara Gonçalves Marcus Krüger Scott J. Harvey Hauke Busch Joern Dengjel Tobias B. Huber 《Kidney international》2013,83(6):1052-1064
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Seidl RO Nusser-Müller-Busch R Hollweg W Westhofen M Ernst A 《Clinical rehabilitation》2007,21(8):686-697
OBJECTIVE: To investigate the success of a neurophysiological dysphagia therapy in patients with neurological disorders. DESIGN: A pre- and post-intervention group study. SETTING: Acute rehabilitation unit. SUBJECTS: Ten patients (swallowing rate <1/5 minutes, Frühreha-Barthel Index <-150, tracheostomy as a result of a swallowing disorder) with dysphagia as a result of a head injury or cerebral haemorrhage. INTERVENTIONS: Therapy was given based on facio-oral tract therapy for three weeks (15 sessions of 1 hour each). MEASURES: The general scales used were the Frühreha-Barthel Index and Coma Remission Scale. Measures of swallowing rate, alertness and swallowing ability were undertaken before, during and after the treatment sessions and at intervals of 30 minutes for 2 hours after the treatment sessions. RESULTS: On the treatment days, the therapy did not lead to an increase in swallowing rate, but did lead to a significant increase in alertness. After completion of a single treatment session, there was a statistically significant decrease in alertness and swallowing rate for 90 minutes. An increase in alertness (Frühreha-Barthel Index and Coma Remission Scale), swallowing ability (measured using an endoscopic examination) and protection of the respiratory tract was observed over the entire therapy period. CONCLUSION: Facio-oral tract therapy led to a statistically significant increase in alertness during the treatment session and, over the entire therapy period, to an increase in swallowing rate, alertness and swallowing ability. The decrease in alertness following therapy sessions must be taken into account in planning rehabilitative measures. Further studies on larger populations as well as studies currently in progress should further elucidate the strategies employed to rehabilitate dysphagic patients. 相似文献
9.
L. Albers S. Ziebarth R. von Kries 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2014,57(8):952-960
Background
Strategies to prevent primary headaches could be very beneficial, especially given that primary headaches can lead to the development of chronic headache. In order to establish headache prevention strategies, the modifiable risk factors for primary headaches need to be identified.Material and methods
A systematic literature search on the risk factors for primary headaches was conducted independently by two persons using the databases MEDLINE and Embase. Further inclusion criteria were observational studies in adult general populations or case-control studies, where the effect sizes were reported as odds ratios or where the odds ratios could be calculated from the given data.Results
In all, 24 studies were included in the analysis. There was a large amount of heterogeneity among the studies concerning headache acquisition, headache classification, and risk factors for headache development. Independent of headache trigger and definition of headache, the association between headache and the risk factor “stress” was very high: The meta-analysis shows an overall effect of 2.26 (odds ratio; 95?%-CI =?[1.79; 2.85]). Studies evaluating neck and shoulder pain also report a strong association with headache; however, these results could not be summarized in a meta-analysis. Equally, the overall effects of smoking and coffee consumption on headaches could not be verified because the effect sizes were rather small and predominantly noticeable only at higher doses.Conclusion
A strong association between headache and the risk factors stress and neck and shoulder pain was confirmed. The effect sizes of smoking and coffee consumption on headaches were rather small. 相似文献10.
Ultrasound is the screening modality of choice for evaluation of the fetal central nervous system (CNS). However, in cases of difficult diagnosis further fetal investigation is desirable. Due to ultrafast magnetic resonance imaging (MRI) techniques artifacts from fetal motions are minimized. MRI involves no exposure to radiation and hence appears to be safe. Due to the better soft tissue contrast, additional investigation by MRI may extend the sonographic diagnosis of fetal CNS-anomalies. Ultrasound and MRI are complementary imaging methods in the evaluation of the fetal CNS. The most important indications for ultrasound are screening for CNS anomalies and serial assessment of the dynamic of the disorder. The most important indications for fetal MRI are the "second opinion" and investigation by fetal MRI instead of postpartum MRI (especially in cases of planned postpartum intervention). In this article the indications and limitations of ultrasound and magnetic resonance imaging in the evaluation of the fetal CNS are discussed. 相似文献