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In a newly developed dual-source computed tomography system (DSCT) the relation of heart rate and image quality and the possible advantages of the system’s superior temporal resolution in the evaluation of left ventricular parameters as compared to results of cardiac magnetic resonance imaging (MRI) were assessed. Coronary CT angiography was performed using a DSCT (Somatom Defintion, Siemens Medical Solutions, Forchheim, Germany) in 21 patients (mean age 62±8; 15 male, 6 female). Image quality of the coronary arteries, the heart valves, and the left ventricular myocardium was assessed using a three-point grading scale. Ten of these patients also underwent cardiac MRI for the assessment of left ventricular function, using a SSFP (steady-state free precession) sequence. Left ventricular ejection fractions (LV-EF), the end-systolic volumes (ESV), and the end-diastolic volumes (EDV) were measured employing MRI and DSCT datasets. The image quality ratings for the coronary arteries at the optimal reconstruction interval were diagnostic even in patients with high heart rates (1.42±0.49). Analysis of global LV function using DSCT quantified from CTA datasets showed a good correlation with results of cardiac MRI [EF: r=0.75 (p=0.01); ESV: r=0.72 (p=0.19); EDV: r=0.71 (p=0.02)]. The dual-source CT system offers robust image quality of the coronary arteries, independent of the heart rate, and provides combined diagnostic imaging of coronary arteries, the heart valves, the myocardium, and the global left ventricular function.  相似文献   
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This study was conducted to determine whether alcoholic and control subjects respond differently to manipulations that either enhance personal involvement (PI) or reduce negative affect (R, relaxation) on tests of neuropsychological function. In Phase 1, 48 male alcoholics and 36 male control subjects completed neuropsychological tasks under standard instructional sets. In Phase 2, subjects completed equivalent forms of these tests under one of three randomly assigned conditions; the PI condition in which subjects were encouraged to identify specific ways of improving their performance, the R condition in which subjects participated in a short relaxation exercise designed to reduce anxiety, or a No Treatment (NT) condition in which no attempt to manipulate the subjects' involvement or affect was made. Alcoholics were inferior to controls in both Phase 1 and Phase 2 [Fs (1,82) > 5.03, ps < 0.03]. The experimental manipulation differentially affected measures of negative affect and effort in the predicted direction. There were no group x condition interactions. Alcoholic and control subjects responded comparably to the experimental manipulations. This investigation, in combination with others using related manipulations, reinforces the hypothesis that alcohol-related cognitives dysfunction reflects an underlying deficit in brain states.  相似文献   
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Complement fixation (CF) was compared to hemagglutination inhibition (HI) as a method for identifying antibody responses to influenza virus vaccination. CF assays were performed at two different laboratories using paired (pre- and postvaccination) sera from 38 vaccinated laboratory employees; HI assays were performed at a third laboratory. As expected, most vaccinees (31/38 = 82%) responded to at least one of three influenza virus antigens as measured by HI. In contrast, only 21% (8/38) of vaccinees showed a response by CF at laboratory 1, and only 29% (11/38) showed a response by CF at laboratory 2. These findings indicate that due to low sensitivity, CF assays should not be used to assess the antibody response to influenza virus vaccination.  相似文献   
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Zusammenfassung Je 10 urämische Patienten und nierengesunde Probanden mit normaler Leberfunktion erhielten entweder 6 mg Phenylbutazon/kg oder 12 mg Aminophenazon/kg KG per os. Beide Pharmaka werden durch mischfunktionelle Oxygenierung im endoplasmatischen Reticulum der Leber abgebaut.Anschließend wurden zu bestimmten Zeiten die Plasmakonzentrationen gemessen und die Plasmahalbwertszeiten beider Substanzen ermittelt.24 h nach Phenylbutazongabe wurde bei Nierengesunden eine mittlere Plasmakonzentration von 4,3±0,85 mg/100 ml gemessen, bei Urämikern dagegen nur 1,75±0,91 mg/100 ml.Die mittlere Plasmahalbwertszeit betrug bei Nierengesunden für Phenylbutazon 50.9±13.5 h, bei Urämikern war sie um 48% auf 75.4±12.8 h verlängert.4 h nach oraler Gabe von Aminophenazon betrug die Plasmakonzentration von Aminophenazon bei Nierengesunden 0,99±0,31 mg/100 ml, bei Urämikern 1,03±0,45 mg/100 ml. Bei urämischen Patienten wurde eine mittlere Aminophenazonhalbwertszeit von 4.1 ± 1.6 h, bei Urämikern von 4.0±1.7 h gemessen.Es bestand keine signifikante Korrelation zwischen den Serumkonzentrationen von Harnstoff oder Kreatinin einerseits und der Plasmahalbwertszeit von Phenylbutazon oder Aminophenazon andererseits.Aus diesen Ergebnissen und den in der Literatur mitgeteilten Befunden wird geschlossen, daß beim Menschen unter den Bedingungen der Urämie eine Beeinflussung des oxydativen Abbaus einzelner lipophiler Pharmaka eintritt. Allgemein gütige Regeln bezüglich der Dosierung von Arzneimitteln, die durch mischfunktionelle Oxygenierung metabolisiert werden, können bei urämischen Patienten aber bis jetzt nicht gegeben werden, da offensichtlich der Abbau verschiedener Substanzen durch die Urämie unterschiedlich beeinflußt wird.Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   
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This paper is an edited version of the Max Hamilton Memorial Lecture that was delivered at the annual meeting of the British Association for Psychopharmacology in Cambridge in July 1989. In tribute to Professor Hamilton's pioneering efforts in the field, the lecture focuses on several aspects of the measurement process in psychopharmacology. The role of enumeration in the classification of psychopathology is reviewed and its importance illustrated with an example drawn from the literature. Attention is given to the fundamental link between agreements within the field about the nature and qualities of clinical phenomena and the field's ability to construct and use multi-item rating scales to measure meaningful changes in the intensity of psychopathology. The importance of global assessment as a validation procedure is emphasized and selected hazards to reliable inference are examined.  相似文献   
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Chronic spinal subdural haematoma is a uncommon. We describe the CT and MRI appearances of chronic spinal and intracranial subdural haematomas following minor trauma. The aetiology, pathogenesis and differential diagnosis are discussed. Received: 7 January 1998 Accepted: 15 July 1998  相似文献   
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The incidence of operative procedures in a group of 374 cleft lip and palate patients was determined by a chart review. These patients were part of a long term study funded by the National Institute of Dental Research at the Lancaster Cleft Palate Clinic. The chart review provided a breakdown of the primary and secondary procedures performed on the patients. Although the secondary procedures carried out were underestimated in this study, it is clear that these operations comprise a major component of the successful treatment of these patients. The results of the study and the implications in today's managed care environment are discussed.  相似文献   
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