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To assess the ability of intravascular ultrasound (IVUS) to image changes in the pulmonary arterial wall associated with pulmonary hypertension (PHT), 10 subjects requiring diagnostic right and left heart catheterization were studied. In addition to measurements of pulmonary artery pressure and pulmonary vascular resistance and pulmonary angiography, when indicated, all underwent simultaneous IVUS imaging in the pulmonary arterial system using a 20 MHz ultrasound transducer mounted on a 2 mm diameter catheter. Four patients had normal pulmonary artery pressures and 6 had varying degrees of PHT. Satisfactory ultrasound images were obtained in 9 out of the 10 patients. In those with normal pulmonary artery pressures ultrasound showed a thin vessel wall with no destinction between separate layers. In patients with systemic PHT, a threelayered vessel wall was apparent and areas compatible with intimai proliferation were seen. In a patient with pulmonary embolic disease areas consistent with mural thrombus were detected at sites of luminal narrowing on the pulmonary angiogram. IVUS is capable of imaging some of the morphological changes in the wall of the pulmonary artery known to occur in longstanding PHT and may therefore become a useful adjunct to haemodynamic measurements and pulmonary angiography for thein vivo assessement of pulmonary vascular disease.Abbreviations IVUS intravascular ultrasound - PHT pulmonary hypertension  相似文献   
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A comparison between praecordial and transoesophageal cross-sectional echocardiography was undertaken in the follow-up of 14 patients who had previously undergone surgical excision of atrial myxoma. The mean interval between surgery and follow-up was 39 months. Evidence of recurrent tumour was seen in two patients by transoesophageal echocardiography but went undetected in one of these using the praecordial approach. Clear visualisation of the atria and interatrial septum was possible in all remaining cases using transoesophageal echocardiography and this allowed confident exclusion of tumour recurrence. Using praecordial echocardiography, technically inadequate studies meant that this was not possible in 4 patients. The significant late recurrence rate of excised atrial myxomas, emphasises the need for serial, postoperative echocardiographic studies. Praecordial echocardiography may be unreliable in the detection of recurrent atrial myxoma in its early stages and for this reason transoesophageal echocardiographic follow-up is justified in high risk patients.  相似文献   
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High adherence is important in microbicide trials, but no adherence interventions to date have demonstrated empiric improvements in microbicide adherence or effectiveness. Approximately midway during the CAPRISA 004 trial, we implemented a novel adherence intervention (Adherence Support Program—ASP), based on an Information–Motivation–Behavioral Skills model and incorporating a Motivational Interviewing approach. We assessed the impact of the ASP on adherence and tenofovir gel effectiveness using a before-and-after comparison. Of the 889 women in the trial, 774 contributed 486.1 women-years of follow-up pre-ASP and 828 contributed 845.7 women-years of follow-up post-ASP. Median adherence rose from 53.6 % pre-ASP to 66.5 % post-ASP. Detectable tenofovir levels increased from 40.6 % pre-ASP to 62.5 % post-ASP in 64 women who had paired tenofovir drug samples. Gel effectiveness improved post-ASP; HIV incidence in the tenofovir gel arm was 24 % lower pre-ASP compared to 47 % lower post-ASP. Following implementation of the ASP, microbicide adherence improved with a concomitant increase in the effectiveness of tenofovir gel.  相似文献   
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Heyde’s syndrome is an under reported systemic disease of gastrointestinal and cardiac manifestation in older adults. It is characterized by a triad of aortic stenosis, angiodysplasia with bleeding and acquired von Willebrand syndrome. It is characterized by proteolysis of high molecular weight multimers of von Willebrand Factor and loss of platelet mediated homeostasis. Heyde’s syndrome is a treatable condition in most cases, especially in the current era of evolution in interventional cardiology and gastroenterology. There are currently no established guidelines in the management of this condition due to paucity of high quality studies, which warrant future trials. High index of suspicion and increasing the awareness of the syndrome among the general practitioners and sub-specialists will improve the diagnostic potential of Heyde’s syndrome. Future studies may change the management aspect of Heyde's syndrome and pave a path for drawing specific guidelines and algorithms. The aim of our review article is to summarize the basic pathophysiology, diagnostics and management of Heyde’s syndrome with a special attention to Transcatheter aortic valve replacement.  相似文献   
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BACKGROUND: Several vitamin A supplementation trials have failed to improve the growth rate in children. Addition of zinc to vitamin A might result in enhanced growth. OBJECTIVE: This study evaluated the effect on growth in children of simultaneous supplementation with zinc and vitamin A. DESIGN: This was a randomized, double-blind, placebo-controlled intervention trial. Six hundred fifty-three children aged 12-35 mo were randomly assigned to 1 of 4 intervention groups: 20 mg Zn/d for 14 d (Z group), 60000 retinol equivalents (200000 IU) vitamin A on day 14 (A group), zinc plus vitamin A (ZA group), or placebo syrup and placebo capsule (placebo group). Weight and length were measured at enrollment and again after 3 and 6 mo. RESULTS: Gains in weight and length during the 6-mo follow-up period were not significantly different among the 4 groups by analysis of variance. Catch-up growth also did not differ significantly among the groups. The proportions of children whose weight-for-age z scores did not change or decreased were 57% in the Z group, 46% in the A group, 50% in the ZA group, and 54% in the placebo group (NS). The proportions of children whose length-for-age z scores did not change or decreased were 42% in the Z group, 48% in the A group, 53% in the ZA group, and 46% in the placebo group (NS). CONCLUSION: Combined short-term zinc supplementation and a single dose of vitamin A has no significant effects on weight and length increments in children over a 6-mo period.  相似文献   
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