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The authors present an improvement to a sigma-filter extrapolation method for the reconstruction of magnetic resonance (MR) images from symmetric discrete Fourier data. By making use of the phase information in the image data, the proposed method can overcome the data inconsistency problem of the original method for handling MR image data with large phase variations, such as those obtained in gradient-echo pulse sequences. Reconstruction results show that its performance is comparable with that of the modified complex sigma-filter method proposed previously to handle the inconsistency problem. However, the new approach has the advantage of reducing computation time by a factor of two with use of a sigma filter applied to real instead of complex images. It is expected that this method will be more practical for use in clinical MR imaging systems.  相似文献   
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Summary We evaluated a bioluminescence assay as a screening test for the detection of bacteriuria in pregnancy. A total of 1,000 urine specimens from a randomly selected group of pregnant women undergoing prenatal surveillance was investigated. Sequential dilution of urine specimens on CLED agar plates served as a reference method. Set against the reference group, bioluminescence screening scored a 93% sensitivity, a 78% specificity and a 99% predictive accuracy for negative results. All urine specimens were also analysed chemically for the presence of nitrite and leucocyte esterase by dip sticks. Dip sticks proved to be insufficient because of poor sensitivities of 54% and 59%, respectively. The bioluminescence assay is an effective, time- as well as labor-saving but questionably cost-effective method for the detection of bacteriuria in pregnancy.
Rascher Nachweis der Bakteriurie bei Schwangeren
Zusammenfassung In der vorliegenden Studie prüften wir die klinische Wertigkeit eines Biolumineszenz-Verfahrens zum Nachweis der Bakteriurie bei Schwangeren. Insgesamt wurden 1000 Routine-Harnproben von Schwangeren untersucht. Als Referenzmethode diente die sequentielle Verdünnung der Harnproben und Ausstreichen auf CLED-Agarplatten. Eine signifikante Bakteriurie konnte mit der Biolumineszenz-Methode mit einer Sensitivität von 93% und einer Spezifität von 78% erkannt werden. Die Voraussagewahrscheinlichkeit für negative Resultate war 99%. Gleichzeitig untersuchten wir alle Harnproben auf Vorhandensein von Nitrit und Leukozyten-Esterase mittels Teststreifen. Die Sensitivitäten lagen nur bei 54% bzw. 59%. Mit Hilfe der Biolumineszenz-Methode kann eine signifikante Bakteriurie bei Schwangeren rasch, verläßlich, aber nur bei relevanter Probenanzahl auch kostengünstig nachgewiesen werden.
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Mutations in APP are associated with familial early-onset Alzheimer disease (FAD). Examination of the genomic sequence in one patient with FAD revealed a change located in the axon 17 of the APP gene at position 275329G>A (GenBank accession number: D87675; GI: 2429080); cDNA sequence 2137G>A (GenBank accession number: X06989; GI: 28720). This corresponds to the mutation A713T in APP. AD stage VI of neurofibrillary degeneration and stage C of Aβ-amyloid burden was found at the post-mortem neuropathological examination. Previous studies have suggested that the mutation A713T in APP is a silent mutation or polymorphism. However, we have not found this change in APP in a control population analyzed by the amplification-refractory mutation system (ARMS). It is concluded that A713T in APP is implicated in the pathogenesis of AD. Since the immunohistochemical study indicates that A713T mutation is not likely to relate with Aβ-amyloid processing, the causative role of this rare mutation remains to be warranted.  相似文献   
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Few studies have systematically assessed executive functioning (EF) skills in boys with XXY, and these are limited by small samples and restricted EF assessment. This study used a broader battery of performance‐based measures as well as parent‐rating scales of EF in 77 boys and adolescents with XXY (mean age = 12.5 years), recruited from a clinical trial and an outpatient clinic. Exploratory factor analyses were used to create EF domains from performance‐based measures, and similar domains were measured using the Behavior Rating Inventory of Executive Function and Conners Parent‐Rating Scales. The boys with XXY showed a distinct EF profile, with the greatest deficit in attention and more moderate deficits in working memory, switching, and planning/problem solving. Parent ratings showed similar challenges, as well as impaired inhibition. Independent sample t‐tests showed no difference on performance measures between boys diagnosed or not diagnosed with attention‐deficit/hyperactivity disorder (ADHD), although parents of boys diagnosed with ADHD reported more difficulties. There were no differences on performance‐based tests between those diagnosed pre‐ and postnatally, although parents of postnatally diagnosed boys reported more metacognitive problems. Language deficits, cognition, and socio‐economic status did not account for EF deficits.  相似文献   
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The laryngeal mask for intubation (MLI), or "Fastrach", is a new device designed by Brain for airway management. The MLI, a modified version of the conventional laryngeal mask, allows for blind intubation through the device using endotracheal tubes up to 8 mm in diameter. Insertion with the head in a neutral position makes this system useful for managing the airway when neck injury is present. The device has been used successfully in patients assessed as having difficult-to-manage airways and its use in emergencies inside or outside the hospital is promising. The MLI has been used with high rates of success in combination with other techniques such as fiberoptic bronchoscopy (success rate 99 to 100%) and transillumination (95 to 100% success rate) in patients whose airways have been considered difficult to manage. Given such high rates of success for MLI placement (95 to 100%) and for blind orotracheal intubation (81 to 100%), the Fastrach may offer an alternative to the conventional laryngeal mask in algorithms for airway management.  相似文献   
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Gastroesophageal reflux disease(GERD) is a frequently encountered disorder. Obesity is an important risk factor for GERD, and there are several pathophysiologic mechanisms linking the two conditions. For obese patients with GERD, much of the treatment effort is focused on weight loss and its consistent benefit to symptoms, while there is a relative lack of evidence regarding outcomes after novel or even standard medical therapy is offered to this population. Physicians are hesitant to recommend operative anti-reflux therapy to obese patients due to the potentially higher risks and decreased efficacy, and these patients instead are often considered for bariatric surgery. Bariatric surgical approaches are broadening, and each technique has emerging evidence regarding its effect on both the risk and outcome of GERD. Furthermore, combined antireflux and bariatric options are now being offered to obese patients with GERD. However, currently Rouxen-Y gastric bypass remains the most effective surgical treatment option in this population, due to its consistent benefits in both weight loss and GERD itself. This article aims to review the impact of both conservative and aggressive approaches of obesity treatment on GERD.  相似文献   
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