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Cross-sectional and Doppler echocardiography are currently the most important non-invasive tests for the evaluation of mitral stenosis. Recent experience has, however, shown that parameters that are reliable before mitral valvotomy may not be valid after the procedure. We have studied the validity of estimation of the area of the mitral valve by echo-planimetry, by Doppler pressure half time and the transmitral end-diastolic pressure gradient calculated by continuous wave Doppler in 100 patients (aged 10-30 years) before and after balloon mitral valvoplasty (n = 70) or surgical closed mitral valvotomy (n = 30). These patients underwent cardiac catheterisation and echocardiographic studies before, immediately after and 8-12 (9.3 +/- 2.2) weeks following balloon valvoplasty or closed valvotomy. The area as estimated echocardiographically correlated well with that obtained by the Gorlin formula before (r = 0.80), but not immediately after (r = 0.67) or on follow up after mitral valvotomy. There was good correlation between Doppler pressure half time and the area as estimated by the Gorlin formula before (r = 0.89) and on follow up after valvotomy (r = 0.82), but the correlation was not as good in the immediate period after valvotomy (r = 0.60). The end-diastolic pressure gradients obtained by Doppler examination and at cardiac catheterisation correlated well with each other before (r = 0.94), immediately after valvotomy (r = 0.92) and on follow up (r = 0.94). Hence, the reliability of estimation of the area of the mitral valve by echo-planimetry and by Doppler pressure half time varies according to the time at which the examination is performed following commissurotomy.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Pharmacological Treatment of Dysphagia in Stroke   总被引:10,自引:0,他引:10  
The pharynx is important for a normal swallow and it has been suggested that pharmacological agents may play a role in the management of pharyngeal dysphagia, but none have been formally evaluated. A pilot double-blind, placebo-controlled study was undertaken in 17 hospitalized patients with persistent dysphagia 2 weeks after stroke. Patients were randomized to treatment with slow-release nifedipine 30 mg orally (n = 8) or placebo (n = 9) following specialist swallowing assessment and videofluoroscopy to exclude severe dysphagia. Videofluoroscopy was repeated after 4 weeks of treatment. Fourteen patients (active 6, placebo 8) completed the study. Two patients died (active 1, placebo 1) and 1 patient in the active group had to be withdrawn because of progressive heart failure. Initial assessment showed impairment in the pharyngeal phase with delayed triggering of swallow, poor laryngeal elevation, and prolonged pharyngeal transit times in all patients. Silent aspiration was seen in 4 patients (active 2, placebo 2). Improvement in swallowing was seen in 8 patients (active 5, placebo 3) at the end of 4 weeks. There were significant changes in the pharyngeal transit time (mean −1.34 second; 95% C.I. −2.56, −0.11) and swallow delay (mean −1.91 seconds; 95% C.I. −3.58, −0.24) in the active group suggesting improvement in the initiation of pharyngeal contractions and reduction in the time taken for the bolus to transverse the pharynx. A similar change was not seen in the placebo group. It is suggested that pharmacological agents such as nifedipine may have a role in the management of stroke-related dysphagia and merit further investigation.  相似文献   
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Sulch D  Kalra L 《Age and ageing》2000,29(4):349-352
BACKGROUND: an organized, goal-defined and time-specified plan of management as envisaged by the integrated care pathway approach can achieve quality outcomes at lower cost. Integrated care pathways may have applications to stroke management because diagnosis is well defined, complex interdisciplinary inputs are required and there is good evidence on best practice. METHOD: we reviewed medical, nursing, rehabilitation and health services databases to identify studies on integrated care pathways in stroke management. Criteria for inclusion were: use of a care pathway or similar methods in acute or rehabilitation settings, randomized studies or non-randomized comparisons with concurrent or historical controls and some form of outcome assessment. RESULTS: we identified six non-randomized studies of acute stroke. One used concurrent controls; the rest used historical controls. Only one study investigated stroke rehabilitation and this used a quasi-randomized controlled design. Five studies in the acute setting demonstrated reduced hospital stay. A reduction in costs of care was reported in all five studies that examined costs. Two studies reported improved uptake of medical interventions. No difference in length of hospital stay, costs or functional status was seen in the rehabilitation study. CONCLUSIONS: integrated care pathway methodology may facilitate quality and cost improvements in stroke care, but evidence is weak and uncertainty exists. Further evidence is needed before implementation in practice.  相似文献   
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The TIM (T cell/transmembrane, immunoglobulin and mucin) proteins are crucial regulators of Th1/Th2 immune responses and have been implicated in several diseases including HIV-1/AIDS. The TIM1 exon 4 that codes for mucin domain is highly diverse, with sequence variants associated with varying phenotypes. In this study, TIM1 exon 4 was sequenced among 227 HIV-1 seroprevalent and 288 healthy non infected individuals from North Indian population and haplotypes established. A novel but rare haplotype D1 was identified among the healthy and differed from D1 by a synonymous substitution G>T at Thr208Thr. The TIM1 haplotype diversity showed no association with susceptibility to HIV-1 infection. The seroprevalent individuals carrying D3A had relatively higher median CD4+T cell counts (368/μl) than those without (313/μl; p = 0.02). A comparison of CD4+T counts between D3-A individuals on ART or ART naïve did not show any significant difference plausibly due to confounding nature of ART and other factors.  相似文献   
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Brain Imaging and Behavior - Cognitive impairment is now recognized in a subset of patients with amyotrophic lateral sclerosis (ALS). The objective of the study was to identify group differences...  相似文献   
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