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101.
Zusammenfassung Im Jahr 1988 wurde erstmals von der m?glichen Wirksamkeit der Valproins?ure in der Migr?neprophylaxe berichtet. Seit 1992 sind insgesamt 359 Patienten in 5 Doppelblindstudien untersucht. In allen Studien ergab sich eine signifikant überlegene Wirksamkeit im Vergleich zu Placebo, eine Studie belegt einen gleichen Effekt wie Propranolol. Es fehlen noch Wirksamkeitsanalysen, die sich am Plasmaspiegel orientieren. Die Nebenwirkungen entsprechen denen aus der Epilepsietherapie, scheinen aber im Vergleich zu Propranolol etwas h?her zu liegen. International und nach den Empfehlungen der Deutschen Migr?ne- und Kopfschmerzgesellschaft gilt Valproins?ure mittlerweile als etabliertes Mittel der zweiten Wahl.   相似文献   
102.
A new computed tomographic and sonographic appearance of renal metastatic melanoma is described. Bilateral cystic masses with thick walls, many with mural nodules, were noted. Sonography also demonstrated complex echopenic masses with irregularly thickened walls and mural nodules.  相似文献   
103.
Sonography detected a paraaortic pulsatile tubular mass in a patient 10 years after “stump” nephrectomy, which was subsequently confirmed as a renal artery-renal vein fistula by computed tomography, angiography, and laparotomy.  相似文献   
104.
Red cell folate specimens were added to the Quality Assurance Program (QAP) of the Royal College of Pathologists of Australasia in 1986. The interlaboratory variation in the results of these red cell folate surveys has been persistently unsatisfactory. This study reports an investigation into the factors contributing to the wide variation of results reported in QAP surveys. Survey results were studied, replies to a questionnaire regarding methods sent to all participants were assessed and some new experimental studies were performed. Factors contributing to the poor QAP results include variation in dilution and diluent, calculation errors, failure to freeze the hemolysate prior to assay and to follow the kit manufactorer's instructions, stability of dithiothreitol, and variations in kit methods, especially in the release of bound folate by "boil" and "no-boil" methods. Photodecomposition and the form and concentration of ascorbate may also be significant. Adequate preparation of the hemolysate sample should ensure release of all protein-bound red cell folate with the reduction of all folates to a single form. Kit manufactures, users and the QAP committee can all contribute in all attempt to rectify current sources of error.  相似文献   
105.
The well-known increased risk of the respiratory distress syndrome in a twin born second as compared with the twin born first is usually attributed to the second twin's predisposition to depression at birth ("asphyxia"). We analyzed the etiologic roles of birth order, presentation, and depression at birth in the development of the respiratory distress syndrome in matched case-control populations drawn from 221 preterm twin pairs. Among the 39 twin pairs discordant for respiratory distress syndrome, the second twin was the affected member in 31 pairs. Second birth order was the only independent risk factor, but only in vaginal deliveries (matched odds ratio, 14.2; 95 percent confidence interval, 2.5 to 81.1). Second twins delivered abdominally did not have an increased risk relative to first twins (odds ratio, 0.9; confidence interval, 0 to 17.8). When depression at birth was evaluated as an outcome variable, malpresentation, rather than birth order, was the major risk factor (independent matched odds ratios of 2.7 [confidence interval, 1.0 to 7.5] and 1.3 [0.7 to 2.5], respectively). Thus, second twins' increased risk of respiratory distress syndrome cannot be explained by a predisposition to depression at birth; a more important factor may be that second twins do not benefit from the salutary effects of labor to the same extent as first twins.  相似文献   
106.
PURPOSE: Recent literature defines certain cognitive errors that emergency physicians will likely encounter. The authors have utilized simulation and debriefing to teach the concepts of metacognition and error avoidance. METHOD: The authors conducted a qualitative study of an educational intervention at Lehigh Valley Hospital during academic year 2002-03. Fifteen emergency medicine residents--eight from postgraduate year three (PGY3) and seven from postgraduate year two (PGY2)--experienced a difficult simulator lab scenario designed to lead them into a cognitive error trap. The debriefing was a PowerPoint with audio format CD-ROM with a didactic on succinylcholine (15 minutes) and cognitive forcing strategies (30 minutes). After debriefing, residents were interviewed by an ethnographer with an 11-question (15-minute) interview and completed an eight-question written survey. RESULTS: The residents ranked this experience second only to direct patient care for educational effectiveness. Survey results (Likert scale, 1 = disagree completely to 5 = agree completely) included "Improved my ability to use succinylcholine" (mean = 4.73), "Improved my ability to diagnose and treat hyperkalemia" (mean = 4.6), and "Cognitive forcing strategies is a useful educational effort" (mean = 4.33). The major interview themes that evolved were that the simulation lab was a positive experience; succinylcholine knowledge was gained; mistakes caused reflection/motivation; the lab was stressful; attending feedback was desired; the lab was realistic; and cognitive forcing strategies were discussed. When asked what they learned, more of the PGY3s commented on cognitive strategies or heuristic techniques (six out of eight), whereas the PGY2s commented on knowledge gained about succinylcholine (five out of seven) and only one PGY2 mentioned cognitive strategies. CONCLUSION: Pilot data suggest that metacognitive strategies can be taught to residents, though they may be better understood by upper-level residents.  相似文献   
107.
Using receiver operating characteristics, the authors examined outcome predictors (variables associated with outcome regardless of treatment) and moderators (variables identifying subgroups with differential treatment effectiveness) in the Multimodal Treatment Study of Children with Attention-Deficit/Hyperactivity Disorder (ADHD; MTA). Treatment response was determined using parent- and teacher-reported ADHD and oppositional defiant symptoms, with levels near or within the normal range indicating excellent response. Among 9 baseline child and family characteristics, none predicted but 3 moderated treatment response. In medication management and combined treatments, parental depressive symptoms and severity of child ADHD were associated with decreased rates of excellent response; when these 2 characteristics were present, below-average child IQ was an additional moderator. No predictors or moderators emerged for behavioral and community comparison treatments. The authors discuss conceptual and clinical implications of research on treatment moderators.  相似文献   
108.
Inhibition of HIV-1 by modification of a host membrane protease   总被引:3,自引:0,他引:3  
While it is clear that CD4 Is the receptor for the gp120 envelopeprotein of HIV-1, substantial evidence suggests that other hostcell proteins are required for successful membrane fusion. Studieswere initiated to examine the potential for a protein receptorwhich has an elastase-like character to participate in fusionof HIV-1 with permissive host cells. A synthetic elastase inhibitorwas shown to significantly reduce HIV-1 infectivity when presentduring, but not after, the initial contact between virus andcells. A human T cell elastase-like membrane component was purifiedand shown to be lipid-associated. By competitive Inhibition,the purified protein was shown to bind gp160 within the HIV-1fusion domain. The binding parameters of whole T cell membraneextract, with a hydrophobic pentapeptide representative of thefusion domain, suggested an elastase-like protein is the single,secondary T cell receptor for HIV-1 (K = 1x103 M–1). Thepentapeptide interacted with porcine and human (epithelial andpolymorphonuclear leukocyte), but not murine, elastase isoforms,suggesting its participation In the permissiveness of host cellsto infection.  相似文献   
109.
110.
A 39-year-old male with acute myelogenous leukemia and concomitant porphyria cutanea tarda was admitted to the hospital for consolidation chemotherapy of his leukemia. During his hospitalization, he developed cellulitis of the left hand and persistent bacteremia with a yellow-pigmented, nonfermenting coryneform bacterium that was identified as Aureobacterium sp. The portal of entry for the Aureobacterium infection was probably through the skin lesions due to porphyria cutanea tarda. The infection developed while the patient was receiving vancomycin prophylaxis, and the vancomycin MIC for the isolate was 32 micrograms/ml.  相似文献   
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