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61.

Background and Purpose

The electrocardiogram (ECG) is commonly used as a screening tool for diagnosis of the ostium secundum atrial septal defect (ASD). We sought to analyze the utility of conventional ECG criteria in detecting right ventricular enlargement (RVE) due to the presence of an ASD.

Methods

Patients who underwent transcatheter or surgical closure of an isolated ASD between 1997 and 2004 were included if an ECG was performed less than 9 months before ASD closure and had echocardiographic RVE.

Results

Of 99 children (aged 6.8 ± 4.7 years; range, 1-18 years) with RVE and ASD, 57% had an ECG that met 1 or more RVE criteria. The sensitivity of ECG increased to 70% in younger patients and to 80% for the largest defects.

Conclusions

Electrocardiographic criteria for RVE are present in just more than over half of young patients with large ASDs. Although ECG is more sensitive in younger patients, it is unreliable as a screen for this lesion.  相似文献   
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Despite pathologic evidence of myocardial inflammation, the significance of myocarditis in children with acute rheumatic carditis remains controversial. Elevations in cardiac troponin I have been demonstrated in other forms of myocarditis. The purpose of our study was to determine if levels of cardiac troponin I are elevated, suggesting myocardial injury, in patients with acute rheumatic carditis. We identified all those patients with acute rheumatic fever, presenting between July 1998 and December 2000, who had clinical evidence of carditis, such as a new murmur of mitral or aortic regurgitation, and who had an echocardiogram, measurements of levels of cardiac troponin I, erythrocyte sedimentation rate, and/or C-reactive protein performed at the time of presentation. Their charts were reviewed for demographic and clinical data. Echocardiograms were reviewed for severity of aortic and mitral regurgitation, and measurements made of left ventricular ejection fraction, fractional shortening, and end-diastolic dimension. We found 16 patients with acute rheumatic carditis, ranging in age from 2.0 to 16.1 years, with just over one-third having symptoms of congestive heart failure. All patients had evidence of acute inflammation. There was a significant relationship between symptoms and severity of mitral regurgitation. No patient had elevated levels of cardiac troponin I level. The fact that levels of cardiac troponin I are not elevated in the serum of children with acute rheumatic carditis suggests that there is minimal myocytic necrosis in this setting. This supports the concept that acute valvar regurgitation is the major hemodynamic abnormality in these patients.  相似文献   
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Interleukin-12 (IL-12) is one of the first cytokines produced by macrophages, key mediators of innate resistance, during the host’s immune response to infections. Therefore, in this study we propose that IL-12 has an important role in the early phase of the immune response to Mycobacterium bovis BCG. IL-12 has been shown to enhance the maturation of protective Th1 cells and gamma interferon (IFN-γ) production during mycobacterial infection. Therefore, it may play a crucial role during the immune phase of infection as well. To examine the role of IL-12 in both the innate and the immune phase of infection, we compared BCG-resistant mice, B10.A (Bcgr), to the susceptible congenic strain B10.A (Bcgs) following administration of a blocking monoclonal antibody to IL-12 (10F6). Anti-IL-12-treated susceptible animals exhibited a two- to threefold increase in spleen CFU by day 21. In contrast, anti-IL-12 treatment had little or no effect on the response of the genetically resistant animals to infection. The B10.A (Bcgr) but not the B10.A (Bcgs) mice had an increase in IFN-γ mRNA relative to baseline levels as early as day 1 of infection irrespective of anti-IL-12 treatment. By day 14, B10.A (Bcgr) mice showed a decrease in IFN-γ mRNA while the B10.A (Bcgs) mice showed a significant increase in IFN-γ mRNA levels. Thus, during BCG infection, the B10.A (Bcgr) mice mount an early IFN-γ response against BCG whereas the B10.A (Bcgs) mice have a delayed IFN-γ response correlating with their genetic permissiveness expressed as an increased mycobacterial load by day 21. Overall, our data demonstrate that the inherent resistance of B10.A (Bcgr) mice to mycobacteria does not depend on optimal levels of IL-12 to maintain effective control of the bacteria, whereas IL-12 is important for the susceptible animals’ response to BCG during the peak of infection.  相似文献   
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Intracranial penetration during attempted nasotracheal intubation is a potentially devastating complication, which should be carefully evaluated and the risk should be addressed in neonatal resuscitation trainings.  相似文献   
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PURPOSE: To explore the state and use of teaching portfolios in promotion and tenure in U.S. medical schools. METHOD: A two-phase qualitative study using a Web-based search procedure and telephone interviews was conducted. The first phase assessed the penetration of teaching portfolio-like systems in U.S. medical schools using a keyword search of medical school Web sites. The second phase examined the current use of teaching portfolios in 16 U.S. medical schools that reported their use in a survey in 1992. The individual designated as having primary responsibility for faculty appointments/promotions was contacted to participate in a 30-60 minute interview. RESULTS: The Phase 1 search of U.S. medical schools' Web sites revealed that 76 medical schools have Web-based access to information on documenting educational activities for promotion. A total of 16 of 17 medical schools responded to Phase 2. All 16 continued to use a portfolio-like system in 2003. Two documentation categories, honors/awards and philosophy/personal statement regarding education, were included by six more of these schools than used these categories in 1992. Dissemination of work to colleagues is now a key inclusion at 15 of the Phase 2 schools. The most common type of evidence used to document education was learner and/or peer ratings with infrequent use of outcome measures and internal/external review. CONCLUSIONS: The number of medical schools whose promotion packets include portfolio-like documentation associated with a faculty member's excellence in education has increased by more than 400% in just over ten years. Among early-responder schools the types of documentation categories have increased, but students' ratings of teaching remain the primary evidence used to document the quality or outcomes of the educational efforts reported.  相似文献   
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