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31.
32.
Robert A Bucek Stefan Puchner Armin Kanitsar Thomas Rand Johannes Lammer 《Journal of endovascular therapy》2007,14(1):70-76
PURPOSE: To evaluate the feasibility and accuracy of automated analysis software for use with multidetector computed tomographic angiography (CTA) in the exact grading of internal carotid artery stenosis. METHODS: A retrospective pilot trial was performed using CTA datasets from 87 stenotic carotid arteries in 46 consecutive patients (34 men; median age 73.5 years) with known cerebrovascular disease. Internal carotid artery (ICA) stenosis was graded according to NASCET criteria by 2 experienced vascular radiologists in consensus using axial source images as well as curved planar reformations and digital subtraction angiography (DSA). These results were then compared to those obtained from the automated CTA analysis software and the results of manually adapted automated CTA analysis. RESULTS: Measurements from automated CTA analysis as well as manually adapted automated CTA analysis correlated significantly to those of axial/reformatted CTA and DSA (r=0.53 and r=0.82, r=0.58 and 0.70, respectively, all p<0.05). Compared to axial/reformatted CTA measurements, automated CTA analysis had a median difference of -16%, while manually adapted automated CTA had a difference of -10%. Corresponding differences in a comparison with DSA were +4% and -2%, respectively. Circumferential calcification or kinking of the ICA origin did not significantly interfere with these differences (all p>0.05). Sensitivities for the detection of ICA stenosis >70% by manually adapted automated CTA analysis and automated measurement were 44.2% and 34.9%, respectively, versus axial/reformatted CTA. Compared with DSA as the gold standard, the sensitivities were 54.2% and 62.5%, respectively. Specificities for both methods and gold standards all exceeded 90%. CONCLUSION: Commercially available automated CTA analysis is a feasible tool, but sensitivities are still not sufficient for clinical application. 相似文献
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Birgit Herting MD Bettina Beuthien‐Baumann MD Katrin Pöttrich PhD Markus Donix MD Antje Triemer PhD Johannes B. Lampe MD Rüdiger von Kummer MD Karl Herholz MD Heinz Reichmann MD Vjera A. Holthoff MD 《Movement disorders》2007,22(4):490-497
Depressive symptoms are common in patients with neurodegenerative disorders. Imaging studies suggest that a disruption of frontal-subcortical pathways may underlie depression associated with basal ganglia disease. This pilot study tested the hypothesis that frontal dysfunction contributes to depression associated with multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). Depressed patients with MSA (n = 11), PSP (n = 9), and age-matched controls (n = 25) underwent measures of cerebral glucose metabolism applying positron emission tomography with (18)F-fluorodeoxyglucose. Regional metabolism in the patient groups was compared to the normal subjects using the voxel-based statistical parametric mapping. Depressive symptom severity (Hamilton Depression Rating) and degree of locomotor disability (Hoehn & Yahr) were assessed in the patient groups. The association between prefrontal metabolism and the occurrence of depressive symptoms and the degree of locomotor disability was investigated. When compared to controls, MSA patients revealed significant metabolic decreases in bilateral frontal, parietal, and cerebellar cortex and in the left putamen. In PSP patients, significant hypometabolism was demonstrated in bilateral frontal cortex, right thalamus, and midbrain. Depression severity but not the patients' functional condition was significantly associated with dorsolateral prefrontal glucose metabolism in both patient groups. The findings of this pilot study support the hypothesis that depressive symptoms in MSA and PSP are associated with prefrontal dysfunction. 相似文献
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Abstract – The dental records made on presentation of 1367 consecutive patients (731 females and 636 males) for orthodontic treatment at a private orthodontic practice between 1998 and 2002 were examined for data relating to trauma to the permanent incisors. The results showed that 10.3% of these patients had suffered from dental trauma before the onset of orthodontic treatment. The highest prevalence of dental trauma was determined in the 11–15 years age group, corresponding to the dental developmental stage of the late mixed dentition. The most frequently affected teeth were the maxillary central incisors (79.6%), and the most common types of trauma were fracture of enamel–dentin without pulpal involvement (42.7%) and fracture of enamel (33.8%). Compared to patients with normal overjet and adequate lip coverage, the frequency of dental trauma was significantly higher in patients with increased overjet and adequate lip coverage ( P = 0.028) or with increased overjet and inadequate lip coverage ( P = 0.003). The results of the present study indicate that a significant percentage of candidates for orthodontic treatment, and especially those with increased overjet and inadequate lip coverage, suffer trauma to their permanent incisors before the onset of orthodontic treatment. It might also be concluded that preventive orthodontic treatment of such patients should be initiated and completed before the age of 11, i.e. in the early to middle mixed dentition. 相似文献
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Claudia Trenkwalder MD Heike Benes MD Ludger Grote MD Svenja Happe MD Birgit Högl MD Johannes Mathis MD Gerda M. Saletu‐Zyhlarz MD Ralf Kohnen PhD CALDIR study group 《Movement disorders》2007,22(5):696-703
We report the first large-scale double-blind, randomly assigned study to compare two active dopaminergic therapies for Restless Legs Syndrome (RLS), the dopamine agonist cabergoline (CAB) and levodopa/benserazide (levodopa). Patients with idiopathic RLS were treated with fixed daily doses of 2 or 3 mg CAB or 200 or 300 mg levodopa for 30 weeks. Efficacy was assessed by changes in the IRLS (International RLS Severity Scale) and by time to discontinuation of treatment due to loss of efficacy or augmentation. 361 of 418 screened patients (age 58 +/- 12 years, 71% females) were randomly assigned and treated (CAB: n = 178; levodopa: n = 183) in 51 centers of four European countries. Baseline IRLS total score was 25.7 +/- 6.8. The baseline-adjusted mean change from baseline to week 6 in IRLS sum score was d = -16.1 in the CAB group and d = -9.5 in the levodopa group (d = -6.6, P < 0.0001). More patients in the levodopa group (24.0%) than in the CAB group (11.9%, P = 0.0029, log-rank test) discontinued because of loss of efficacy (14.2% vs. 7.9%, P = 0.0290) or augmentation (9.8% vs. 4.0%, P = 0.0412). Adverse events (AEs) occurred in 83.1% of the CAB group and in 77.6% of the levodopa group. In both groups, most frequent AEs were gastrointestinal symptoms (CAB: 55.6%, levodopa: 30.6%, P < 0.0001). This first large-scale active controlled study in RLS showed superior efficacy of cabergoline versus levodopa after a 30-week long-term therapy. Tolerability was found more favorable with levodopa than with cabergoline. 相似文献
37.
Is there a place for gastroenterostomy in patients with advanced cancer of the head of the pancreas? 总被引:4,自引:0,他引:4
George P. van der Schelling M.D. Rene P. van den Bosch M.D. Jean H. G. Klinkenbij M.D. Paul G. H. Mulder M.Sc. Johannes Jeekel M.D. Ph.D. 《World journal of surgery》1993,17(1):128-132
There remains doubt about the need for gastroenterostomy in patients with advanced cancer of the pancreatic head, performed either prophylactically or when passage of food becomes impossible. The records of 142 patients admitted for advanced pancreatic cancer to the Erasmus University Hospital over a period of 11 years were reviewed. We concentrated especially on the pre- and postoperative intake of food in cases involving gastroenterostomy and the morbidity and mortality associated with abdominal surgery in these patients. Of 129 patients without symptoms of gastric outlet obstruction at the time of diagnosis, 31 underwent prophylactic gastroenterostomy. The procedure did not prevent gastric outlet obstruction in 4 patients. Of the remaining 98 patients, 15 developed gastric outlet obstruction. Cox proportional hazards analysis showed no significant difference in the interval to the occurrence of a symptomatic obstruction between these two groups, taking into account other covariables. Postoperative complications and mortality regarding a gastroenterostomy were high, ranging from 9% to 41% and 11% to 33%, respectively. Our results do not indicate that prophylactic gastroenterostomy may significantly prevent future gastric outlet obstruction; therefore, as it also increases morbidity, it should not be performed. A gastroenterostomy to relieve symptoms should be considered carefully, as the success rate is low and is accompanied by a considerable incidence of morbidity and mortality.
Resumen Persiste la duda sobre la necesidad de practicar gastroenterostomía en pacientes con cáncer avanzado de la cabeza del páncreas, así sea profiláctica o en presencia de obstrucción al paso de los alimentos. Se revisaron las historias de 142 pacientes con cáncer avanzado de la cabeza del páncreas en el Hospital de la Universidad de Erasmo observados en un periodo de 11 años. El estudio se concentré especialmente sobre la ingesta pre y postoperatoria de alimentos en los pacientos con gastroenterostomía y en la morbilidad y mortalidad asociada con la cirugía abdominal. De 129 pacientes libres de síntomas de obstrucción en el momento del diagnóstico, 31 fueron sometidos a gastroenterostomía profiláctica; el procedimiento no logró prevenir la obstrucción gástrica en 4 casos. De los 98 pacientes restantes, 15 desarrollaron obstrucción gástrico. El análisis proporcional de Cox no demostró diferencia significativa en el intervalo transcurrido hasta la aparición de los sintomas entre los dos grupos, tomando en consideración diversas variables. Las tasas de complicaciones y de mortalidad postoperatoria en relación con la gastroenterostomía fueron elevadas, 9–41% y 11–33%, respectivamente. Nuestros resultados no indican que la gastroenterostomía profiláctica pueda prevenir la obstrucción gástrica y, por cuanto incrementa la morbilidad, no debe ser realizada. La gastroenterostomía por razones de sintomatologia debe ser cuidadosamente considerada, puesto que la tasa de éxito es baja y se acompana de considerable morbilidad y mortalidad.
Résumé Réaliser une gastroentérostomie de faÇon prophylactique ou seulement lorsque l'alimentation devient impossible chez un patient ayant un cancer de la tÊte du pancréas reste une question sans réponse. Les dossiers de 142 patients ayant un cancer avancé de la tÊte du pancréas, observés à l'HÔpital Universitaire Erasmus en l'espace de 11 ans, ont été revus. Nous avons noté la possibilité d'alimentation en périodes préet postopératoire ainsi que la morbidité et mortalité en rapport avec la chirurgie chez ces patients. Des 129 patients n'ayant pas de symptÔmes d'obstruction postpylorique au moment du diagnostic, 31 ont eu une gastroentérostomie à titre prophylactique. Cette intervention n'a pu prévenir l'obstruction chez 4 de ces patients. Des 98 autres patients, 15 ont développé une obstruction postpylorique. Une analyse multifactorielle selon le modèle de Cox n'a pu démontrer de différence significative entre les deux groupes pour l'intervalle entre le moment du diagnostic et la survenue de l'obstruction. Le taux de complications et de décès postopératoires après gastroentérostomie était élevée, variant respectivement entre 9% et 41% et 11% et 33%. Nos résultats indiquent que la gastroentérostomie à titre prophylactique ne prévient pas la survenue d'une obstruction postpylorique mais qu'elle accroÎt la morbidité. Dans ces conditions, la gastroentérostomie ne devrait Être réalisée qu'en cas d'obstruction symptomatique, mais en sachant qu'elle n'est pas toujours couronnée de succès et que les taux de mortalité et de morbidité ne sont pas nuls.相似文献
38.
Helmut Seidel Barbara Harazin Kristina Pavlas Christine Sroka Jörg Richter Ralph Blüthner Udo Erdmann Jan Grzesik Barbara Hinz Reinhard Rothe 《International archives of occupational and environmental health》1988,61(1-2):95-106
Summary This study was carried out in order: (1) to examine the effects of isolated and combined prolonged exposures to noise and whole-body vibration on hearing, vision and subjectively experienced strain, and (2) to check the combined effects with repeated exposures. Six male subjects were exposed twice to noise (N) at 92 dBA, whole-body vibration (V) in the Z-axis at 4 Hz and 1.0 ms–2 rms, and noise and vibration (NV) for 90 min with each condition. Temporary threshold shifts of hearing (TTS) and their integrals (ITTS) were measured at 4, 6, 10, and 12 kHz. Visual acuity was examined by means of a very sensitive test. Cross-modality matching (CMM) of the handgrip force was used to judge the subjectively experienced strain. NV induced a clear tendency of higher TTS and ITTS than N, with several significant differences most pronounced at 10 kHz. With repeated exposures, the effect of NV decreased, while the reactions to N and V remained unchanged. The individual reactions to NV differed. The influence of the duration of exposures on vision depended on the condition; N caused time-dependent changes, whereas V did not. CMM-data increased with the duration of the exposure during V and NV. N was generally judged to be more straining than V; NV caused higher strain than V during the first 30 min of exposure only. Correlations between different effects suggest certain links between them. Additionally, less motivation — daily obtained by a questionnaire — often correlated with higher ITTS during N and NV. The results also illustrate the combined effects on the individual susceptibility, repetition of exposure, the kind of response, and, possibly, the actual psychic state.Abbreviations CMM
cross-modality matching
- MVC
maximum voluntary contraction force
- N
exposure condition: noise level 92dBA, no whole-body vibration
- NV
exposure condition: combined exposure to noise with a level of 92 dBA and wholebody vibration with 4 Hz, 1 ms–2 rms
- V
exposure condition: whole-body vibration with 4 Hz, 1 ms–2 rms
- TTS
temporary threshold shift
- ITTS
integral of temporary threshold shift
- WBV
whole-body vibration in the common sense
This work was done in the Temporary International Research Team on Combined Effects of Noise and Vibration of the Council of Mutual Economic Assistance of the Socialist Countries. The authors gratefully acknowledge the help and assistance of L.-M. Brumm, Y. Bening, M. Godau, G. Weber, and R. Vizcaino. 相似文献
39.
Susanne K. Kjaer Claus Dahl Gerda Engholm Johannes E. Bock Elsebeth Lynge Ole M. Jensen 《Cancer causes & control : CCC》1992,3(4):339-348
Sexual, reproductive and venereal risk factors for cervical neoplasia were investigated in a population-based case-control study of 586 women with histologically verified, cervical squamous-cell carcinoma in situ, and 59 women with invasive squamous-cell cervical cancer, diagnosed from 1985 to 1986 in Copenhagen. Cases were identified from the computerized Danish Cancer Registry. An age-stratified control group (n=614) was drawn at random from the female population in the study area by means of the Danish Central Population Register. A structured questionnaire was mailed to cases as well as controls. Increasing number of sexual partners exerted a significant effect on the risk both for carcinoma in situ, and invasive cancer, independently of age at first intercourse and other potential confounders. Conversely, the association with early age at first intercourse became statistically insignificant after allowance for other risk factors, although an increasing risk was still observed with decreasing age at sexual debut. Early age at first episode with genital warts was a significant risk factor for carcinoma in situ, perhaps indicating a possible increased susceptibility of the cervix epithelium during adolescence. A history of genital warts was a good predictor of risk for carcinoma in situ, whereas a history of previous gonorrhea was associated with an increased risk for invasive carcinoma. Women with multiple births had a significantly increased adjusted risk, especially for carcinoma in situ, although some association was also observed with invasive cervical cancer. The study supports the hypothesis of cervical neoplasia being a sexually transmitted disease, and that carcinoma in situ and invasive cervical carcinoma, to a high degree, have similar patterns of risk factors.Drs Kjaer, Engholm, and Lynge are with the Danish Cancer Registry. Dr Dahl is with the Department of Surgery, Slagelse Hospital, Denmark. Dr Bock is with the Department of Gynecology, Rigshospitalet, Copenhagen, Denmark. Dr Jensen, formerly with the Danish Cancer Registry, is deceased. Address correspondence to Dr Kjaer, Danish Cancer Registry, Institute of Cancer Epidemiology, Danish Cancer Society, Rosenvengets Hovedvej 35, Box 839, Copenhagen. Denmark. The Danish Cancer Society supported this study through grants. 相似文献
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