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71.
BackgroundReference values for cardiac magnetic resonance imaging (cMRI) in children and young adults are scarce. This leads to risk stratification of patients with congenital heart diseases being based on volumes indexed to body surface area (BSA). We aimed to produce cMRI Z score equations for ventricular volumes in children and young adults and to test whether indexing to BSA resulted in an incorrect assessment of ventricular dilation according to sex, body composition, and growth.MethodsWe retrospectively included 372 subjects aged < 26 years with either normal hearts or conditions with no impact on ventricular volumes (reference group), and 205 subjects with repaired tetralogy of Fallot (TOF) aged < 26 years. We generated Z score equations by means of multivariable regression modelling. Right ventricular dilation was assessed with the use of Z scores and compared with indexing to BSA in TOF subjects.ResultsVentricular volume Z scores were independent from age, sex, and anthropometric measurements, although volumes indexed to BSA showed significant residual association with sex and body size. In TOF subjects, indexing overestimated dilation in growing children and underestimated dilation in female compared with male subjects, and in overweight compared with lean subjects.ConclusionsIndexed ventricular volumes measured with cMRI did not completely adjust for body size and resulted in a differential error in the assessment of ventricular dilation according to sex and body size. Our proposed Z score equations solved this problem. Future studies should evaluate if ventricular volumes expressed as Z scores have a better prognostic value than volumes indexed to BSA.  相似文献   
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Summary Different mutations of the phenylalanine hydroxylase (PAH) gene leading to phenylketonuria (PKU) have been described associated with specific haplotypes in several European countries. In order to investigate the distribution of DNA haplotypes in Italy, restriction fragment length polymorphism (RFLP) analysis of the PAH gene was performed in nine Italian PKU patients from eight unrelated families, and in the available relatives. The analysis of eight polymorphic sites revealed haplotypes 1 and 6 in association with PKU. This pattern appears to differ from those reported for other European populations.The majority of the 14 PKU subjects studied showed compound heterozygosity for different haplotypes, as observed for other European series.RFLP analysis at the PAH locus allowed us to offer the possibility of prenatal diagnosis to six of the studied families. One prenatal diagnosis was performed and a normal fetus was diagnosed.  相似文献   
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Three patients with hemophilia presented with hemothoraces which resolved within 1-3 weeks following treatment with factor concentrates. Drainage of blood was not necessary. Eight previously reported cases are reviewed, and therapy and complications are summarized. We suggest that treatment of this rare complication of hemophilia with factor concentrates and avoidance of surgical intervention is indicated.  相似文献   
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The HandiHaler is a novel breath-actuated dry powder system designed for the delivery of tiotropium 18microg daily in the treatment of COPD. We compared patient ability to use the HandiHaler or metered dose inhaler (MDI) device correctly 4 weeks after receiving brief instructions and device demonstration. A single-blind study was conducted in COPD patients in two centers in Denmark. ALL patients (n = 151) received one placebo capsule via the HandiHaler daily and ipratropium (20 microg) two actuations via the MDI q.i.d. Mean FEV1 for all patients was 1.25 + 0.54 (46% predicted). Twelve instructions establishing proper device use were evaluated for the MDI and Handihaler. Error scores were analyzed by number of patients with less, equal or more errors when using HandiHaler compared to MDI in the total efficacy population (n = 139) and according to those who had not previously used an MDI for at least 12 months (MDI beginners) (n = 74) and those who had used an MDI (MDI experienced) (n = 65). Four weeks after device instruction, a higher proportion of patients in the total population (P < 0.01) had fewer errors with the HandiHaler (35.3%) compared to the MDI (15.1%). The number of errors was equal in 50% of patients. Similar findings were observed in the subgroup of patients who were MDI beginners (42% vs. 11%, P < 0.01) with non-significant trends in favor of the HandiHaler in those patients who were MDI experienced (29.7% vs. 18.9%, P = 0.096). Similar results in favor of HandiHaler were noted across different age and sex strata. The proportion of patients correctly using the device on the first of three attempts was 59.7% and 54.7% for the HandiHaler and MDI, respectively (P = 0.399). In summary, use of the HandiHaler can be easily taught with fewer errors compared to the MDI. Furthermore, patient performance using the HandiHaler was superior to that with an MDI despite prior MDI experience and more frequent usage.  相似文献   
76.
This study evaluated whether formaldehyde, at concentrations similar to those found in the indoor environment, could produce adverse effects on the lower airway of 15 asthmatic persons with documented bronchial hyperresponsiveness who were exposed for 90 min in a climate chamber to clean air containing formaldehyde vapor at levels of 0.85 mg/m3, 0.12 mg/m3, and 0.008 mg/m3. No significant changes in forced expiratory volume in 1 sec (FEV1), airway resistance (Raw), specific airway resistance (SRaw), and flow-volume curves could be detected during formaldehyde exposure. Furthermore, histamine challenge tests performed immediately after formaldehyde exposure showed no evidence of changes in bronchial reactivity. No late reactions were registered during the first 14-16 hr after exposure. The results suggest that residential levels of formaldehyde are of minor importance in the emergence of pulmonary symptoms. Discrepancies between the present study and previous data may be due to differences in environmental conditions.  相似文献   
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BackgroundEnterococcal bacteraemia (EB) is common, particularly in the nosocomial setting, and its management poses a challenge for clinicians and microbiologists.ObjectivesThe aim was to summarize the more relevant features of EB and to provide a practical state-of-the-art on the topics that more directly affect its management.SourcesPubmed articles from inception to 31 May 2020.ContentThe following topics are covered: epidemiological, clinical and microbiological characteristics and factors associated with prognosis of EB; diagnosis and work-up, including the use of echocardiography to rule out endocarditis; antibiotic management with special focus on antimicrobial resistance and complicated EB; and the role of infectious disease consultation and the use of bundles in EB. In addition, three clinical vignettes are presented to illustrate the practical application of the guidance provided, and major gaps in the current evidence supporting EB management are discussed.ImplicationsEB is associated with large burdens of morbidity and mortality, particularly among fragile and immunosuppressed patients presenting complicated bacteraemia due to multidrug-resistant enterococci. Most cases of EB are caused by Enterococcus faecalis, followed by E. faecium. EB often presents as polymicrobial bacteraemia. Rapidly identifying patients at risk of EB is crucial for timely application of diagnostic techniques and empiric therapy. Early alert systems and rapid diagnostic techniques, such as matrix-assisted desorption ionization–time of flight mass spectrometry, especially if used together with infectious disease consultation within bundles, appear to improve management and prognosis of EB. Echocardiography is also key in the work-up of EB and should probably be more extensively used, although its exact indications in EB are still debated. Multidisciplinary approaches are warranted due to the complexity and severity of EB.  相似文献   
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