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31.
The acute hemodynamic effects of captopril were evaluated at cardiac catheterization in 16 children (age, 0.3-18 years) with cardiomyopathy. Twelve children had congestive cardiomyopathy, whereas four had restrictive cardiomyopathy. Hemodynamic measurements were obtained 30 and 60 minutes after the oral administration of captopril (0.5 mg/kg). Blood pressures were measured in the aorta, pulmonary artery, right atrium, and pulmonary capillary wedge position; cardiac outputs were measured by the thermodilution technique. Hemodynamic data could not be obtained after the administration of captopril in one child with congestive cardiomyopathy because of an immediate, severe hypotensive response. In 11 of 12 children with congestive cardiomyopathy, cardiac index increased by 22%, from 2.3 to 2.8 l/min/m2 (p less than 0.05), and stroke volume increased by 22%, from 23 to 28 ml/m2 (p less than 0.05). Systemic vascular resistance decreased from 32 to 21 units.m2 (p less than 0.01), but the mean aortic pressure did not change significantly. In contrast, four children with restrictive cardiomyopathy had no change in cardiac output after captopril, but there was a trend toward significant arterial hypotension (mean aortic pressure decreased from 78 to 59 mm Hg). Thus, captopril acutely reduced systemic vascular resistance and increased both cardiac output and stroke volume in children with congestive cardiomyopathy. In children with restrictive cardiomyopathy, however, captopril did not affect cardiac output, but it did decrease aortic pressure. These data indicate that captopril may benefit children with a congestive cardiomyopathy but that captopril probably should not be used in children with restrictive disease.  相似文献   
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Telomere length (TL) has been associated with aging and mortality, but individual differences are also influenced by genetic factors, with previous studies reporting heritability estimates ranging from 34 to 82%. Here we investigate the heritability, mode of inheritance and the influence of parental age at birth on TL in six large, independent cohort studies with a total of 19 713 participants. The meta-analysis estimate of TL heritability was 0.70 (95% CI 0.64–0.76) and is based on a pattern of results that is highly similar for twins and other family members. We observed a stronger mother–offspring (r=0.42; P-value=3.60 × 10−61) than father–offspring correlation (r=0.33; P-value=7.01 × 10−5), and a significant positive association with paternal age at offspring birth (β=0.005; P-value=7.01 × 10−5). Interestingly, a significant and quite substantial correlation in TL between spouses (r=0.25; P-value=2.82 × 10−30) was seen, which appeared stronger in older spouse pairs (mean age ≥55 years; r=0.31; P-value=4.27 × 10−23) than in younger pairs (mean age<55 years; r=0.20; P-value=3.24 × 10−10). In summary, we find a high and very consistent heritability estimate for TL, evidence for a maternal inheritance component and a positive association with paternal age.  相似文献   
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Background and purposeFlow diverters are increasingly used to treat intracranial aneurysms. We report the safety and efficacy of the p64 flow diverter, a resheathable and detachable device for intracranial aneurysms.Materials and methodsWe retrospectively reviewed 108 patients with 109 aneurysms treated with the p64 between March 2014 and July 2019. There were 87 women and 21 men, mean age 57 years. Of 109 aneurysms, 74 were discovered incidentally, 12 were symptomatic, 18 were previously treated, and five were ruptured dissection aneurysms. A total of 10 aneurysms were located in the posterior circulation. The mean aneurysm or remnant size was 8.1 mm.ResultsHemorrhage by perforation with the distal guidewire occurred in two patients with permanent neurological deficits in one. In one patient, acute in-stent occlusion caused infarction with a permanent deficit. Permanent morbidity was 1.9% (2 of 108, 95%CI 0.1–6.9%); there was no mortality. During follow-up, three in-stent occlusions occurred, all asymptomatic. There were no delayed hemorrhagic complications. At six months, 77 of 96 aneurysms (80.2%) were completely occluded, and at last follow-up, this increased to 93 of 96 aneurysms (96.9%). In-stent stenosis at any degree occurred in 11 patients, progressing to asymptomatic complete occlusion in one. In the other patients, stenosis resolved or improved at further follow-up.ConclusionThe p64 offers an effective and safe treatment option. Aneurysm occlusion rate was 97% at last follow-up, mostly achieved with a single device. There were no delayed hemorrhagic complications. Delayed in-stent stenosis infrequently progresses to occlusion but remains a matter of concern.  相似文献   
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Identifying factors that predict health-related quality of life (QOL) following hematopoietic SCT, is important in estimating patients' abilities to adjust to the consequences of their disease and treatment. As the studies that have been published on this subject are scattered, the present study aimed to systematically review prognostic factors for health-related QOL after auto- and allo-SCT in hematological malignancies. A systematic, computerized search in Medline, EMBASE, PsycINFO and the Cochrane Library was conducted from 2002 to June 2010. The methodological quality of the studies was assessed using an adaptation of Hayden's criteria list. Qualitative data synthesis was performed to determine the strength of the scientific evidence. In all, 35 studies fulfilled the selection criteria. Strong-moderate evidence was found for GVHD, conditioning regimen, being female, younger age, receiving less social support and pre-transplant psychological distress as predictors of various aspects of health-related QOL following hematopoietic SCT. The results of this review may help transplant teams in selecting patients at risk for experiencing a diminished health-related QOL following hematopoietic SCT. Follow-up treatment can be provided in order to promote QOL.  相似文献   
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Clinical, laboratory and electrodiagnostic studies are the mainstay in the diagnosis of polyneuropathy. An accurate etiological diagnosis is of paramount importance to provide the appropriate treatment, prognosis and genetic counselling. High resolution sonography of the peripheral nervous system allows nerves to be readily visualized and to assess their morphology. Ultrasonography has brought pathophysiological insights and substantially added to diagnostic accuracy and treatment decisions amongst mononeuropathies. In this study the literature on its clinical application in polyneuropathy is reviewed. Several polyneuropathies have been studied by means of ultrasound: Charcot–Marie–Tooth, hereditary neuropathy with liability to pressure palsies, chronic inflammatory demyelinating polyneuropathy, Guillain‐Barré syndrome, multifocal motor neuropathy, paraneoplastic polyneuropathy, leprosy and diabetic neuropathy. The most prominent reported pathological changes were nerve enlargement, increased hypo‐echogenicity and increased intraneural vascularization. Sonography revealed intriguingly different patterns of nerve enlargement between inflammatory neuropathies and axonal and inherited polyneuropathies. However, many studies concerned case reports or case series and showed methodological shortcomings. Further prospective studies with standardized protocols for nerve sonography and clinical and electrodiagnostic testing are needed to determine the role of nerve sonography in inherited and acquired polyneuropathies.  相似文献   
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Pharmacological safety evaluation of (pro) drugs includes cardiac safety assessment of proarrhythmic liability in healthy tissue with emphasis on the rapid component of the delayed rectifier (I(Kr)). The lack of (1) an arrhythmic end point, (2) tests in remodeled, predisposed tissue, and (3) testing chronic drug influence on channel trafficking impairs on the drawn conclusions of these assays regarding drug safety. Moreover, the currently used human ether-à-go-go-related gene assays, action potential duration, prolongation in multicellular preparations, or the QT interval have significant shortcomings in their prediction of an increased risk for drug-induced torsades de pointes arrhythmia. In this review, it will be proposed that beat-to-beat variability of repolarization quantified as short-term variability can (1) discriminate between safe and unsafe drugs even under predisposed and highly arrhythmogenic conditions despite accompanying QT prolongation and (2) identify the individual at risk for subsequent arrhythmic events.  相似文献   
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