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101.
A method is presented for 3D MRI in an extended field of view (FOV) based on continuous motion of the patient table and an efficient acquisition scheme. A gradient-echo MR pulse sequence is applied with lateral (left-right (L/R)) frequency-encoding direction and slab selection along the direction of motion. Compensation for the table motion is achieved by a combination of slab tracking and data alignment in hybrid space. The method allows fast k-space coverage to be achieved, especially when a short sampling FOV is chosen along the direction of table motion, as is desirable for good image quality. The method can be incorporated into different acquisitions schemes, including segmented k-space scanning, which allows for contrast variation with the use of magnetization preparation. Head-to-toe images of volunteers were obtained with good quality using 3D spoiled gradient-echo sequences. As an example of magnetization-prepared imaging, fat/water separated images were acquired using chemical shift selective (CHESS) presaturation pulses.  相似文献   
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Coronary magnetic resonance angiography (CMRA) is a technique in clinical evolution. Current clinical applications include assessment for coronary anomalies, aneurysms, bypass graft patency, and, in experienced centers, the exclusion of proximal and multivessel coronary artery disease (CAD). As local expertise increases and more extensive multicenter data become available, additional applications will be established. CMRA promises to supplement and in some cases obviate the need for X-ray contrast angiography, and to expand our understanding of the pathophysiology of CAD. Zusammenfassung Die Magnetresonanzangiographie der Koronargefäße (CMRA) ist eine sich ständig weiterentwickelnde Technik. Etablierte Anwendungen sind zurzeit die Beurteilung von koronaren Anomalien, Aneurysmen und der Durchgängigkeit von Bypasses. Auch der Ausschluss proximaler Koronarstenosen und einer koronaren Mehrgefäßerkrankung ist in einigen spezialisierten Zentren möglich. Mit zunehmender Erfahrung der jeweiligen Anwender und der Verfügbarkeit von Ergebnissen großer multizentrischer Studien können zukünftig weitere klinische Anwendungen etabliert werden. In der Zukunft könnte die CMRA ergänzende Informationen zur Indikationsstellung einer konventionellen Röntgenangiographie bringen und in einigen Fällen diese Untersuchung sogar ersetzen. Die CMRA wird unseren Einblick in die Pathophysiologie der koronaren Herzerkrankung sicher erweitern.  相似文献   
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The study of brain function using MRI relies on acquisition techniques that are sensitive to different aspects of the hemodynamic response contiguous to areas of neuronal activity. For this purpose different contrasts such as arterial spin labeling (ASL) and blood oxygenation level dependent (BOLD) functional MRI techniques have been developed to investigate cerebral blood flow (CBF) and blood oxygenation, respectively. Analysis of such data typically proceeds by separate, linear modeling of the appropriate CBF or BOLD time courses. In this work an approach is developed that provides simultaneous inference on hemodynamic changes via a nonlinear physiological model of ASL data acquired at multiple echo times. Importantly, this includes a significant contribution by changes in the static magnetization, M, to the ASL signal. Inference is carried out in a Bayesian framework. This is able to extract, from dual-echo ASL data, probabilistic estimates of percentage changes of CBF, R(2) (*), and the static magnetization, M. This approach provides increased sensitivity in inferring CBF changes and reduced contamination in inferring BOLD changes when compared with general linear model approaches on single-echo ASL data. We also consider how the static magnetization, M, might be related to changes in CBV by assuming the same mechanism for water exchange as in vascular space occupancy.  相似文献   
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The objective of this study is to test the luminous efficiency functions V(lambda), V'(lambda), V(10)(lambda) and their linear combinations on the basis of a data set gained from a simulated mesopic night-time driving experiment. Another aim is to provide 'real-world' data for the 'X framework' or 'linear combination model', and to find out its limits in a practical situation. Human performance was measured by the reaction time method. Results show that the single parameter of the linear combination of photopic and scotopic luminous efficiency functions can be determined analytically with little variation for a given mesopic background luminance level and a given visual target colour, but the computation leads to considerable deviations comparing all three target colours (red, green and blue) used in the experiment. The conclusion for the given experimental conditions is that the single parameter of the linear combination model has an increasing deviation for lower background luminance levels.  相似文献   
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BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials.  相似文献   
106.
Zusammenfassung Diese Studie untersucht, wie Erfolg im Einzelcoaching entsteht und was Psychodrama dazu beitragen kann. Dabei werden zun?chst die vier Berner Wirkfaktoren dargestellt, die im Rahmen einer allgemeinen psychologischen Coachingkonzeption die vier m?glichen Erfolgsstrategien darstellen. über Videoauswertung und schriftliche Befragung aller Beteiligten wurden 35 Einzelsitzungen evaluiert. Dabei zeigten sich die vier Wirkfaktoren tats?chlich als elementar in kurz- und mittelfristig erfolgreichen Coachingprozessen. In dem experimentellen Vergleich wurde das psychodramatische Coaching zudem wesentlich besser bewertet als das Vergleichscoaching, was durch den Ressourcen- und Wachstumsfokus sowie die sehr gute Beziehungskompetenz der Psychodramatiker erkl?rt werden kann. Des Weiteren zeigen die Auswertungen, dass ein dosierter und gezielter Einsatz des psychodramatischen Methodenrepertoires fruchtbarer zu sein scheint als der zeitlich umfassende Einsatz des Psychodramas als Hauptinterventionsmethode.
Summary The present study investigates the process of success development in one-to-one-coaching and examines how the method of psychodrama can contribute to this process. First the four change factors are presented. They represent the four success strategies in a general psychological coaching approach that can be chosen by the coach. Second 35 one-to-one-coaching sessions are evaluated by a video-based rating-system and questionnaires that were filled in by all coaches, clients and employees of the clients. In these analyses the four change factors were shown to be critical for short- and medium-term success. In an experimentally designed assessment the psychodramatic coachings had a considerably better result than the comparative coaching. This outcome could be explained by the focus on resources and growth and the high competence of the psychodramatic coaches to set up an appreciative coaching relationship. The analyses demonstrate furthermore that the well-aimed and specific use of psychodrama methods is more fruitful than its time-extensive use as the main intervention method.


Peter Behrendt geb. 1977, Dipl. Psych., ausgebildeter Psychodrama-Therapeut und Mediator, seit 2004 freiberuflich Coaching, Moderation sowie Konzeption und Durchführung von Fortbildung und Trainings. Er konzipierte und leitete die Evaluationsstudie, die diesem Artikel zugrunde liegt.  相似文献   
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