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21.
OBJECTIVE: This prospective study was designed to investigate the differences between asymptomatic versus symptomatic arrhythmia as well as left ventricular dysfunction in a consecutive population of patients with persistent atrial fibrillation. DESIGN: A total of 282 consecutive outpatients referred with persistent atrial fibrillation formed the study population. A structured medical history was obtained. A two-dimensional transthoracic echocardiography to assess the left ventricular function and a 24-h electrocardiogram (ECG) recording were performed. Irregularity of the heart rhythm was analysed with heart rate variability (HRV) in the time domain as well as maximum and minimum heart rate and the longest pause. SETTING: Three university hospitals. RESULTS: The mean age of the patients was 69 years and the mean duration of atrial fibrillation was 7 months. The prevalence of symptomatic patients was 68%, while 32% had no symptoms from atrial fibrillation, left ventricular dysfunction was observed in 20%. Asymptomatic subjects had more often lone atrial fibrillation than those with symptoms. Valvular heart disease was an independent predictor of symptoms while male gender, ischaemic heart disease and a high heart rate were independent predictors of impaired left ventricular function. CONCLUSION: Valvular heart disease is related to symptoms in persistent atrial fibrillation. Ischaemic heart disease, male gender and a high heart rate are more common in patients with impaired left ventricular function. Compromised left ventricular function does, occur also in asymptomatic subjects underlining the importance of a careful investigation including echocardiography in all subjects with persistent atrial fibrillation.  相似文献   
22.
The results of Kr-81m/Tc-99m ventilation-perfusion (VP) lung scintigraphy were correlated with the results of pulmonary angiography for 74 patients suspected of having pulmonary embolism (PE). Among patients having a diagnostic scan, the sensitivity and specificity of scintigraphy were 91% and 94%, respectively. Also, 157 consecutive cases of Kr-81m/Tc-99m VP lung scintigraphy were reviewed, and the frequency of an indeterminate scan was found to be 22%. A similar frequency was found for VP scintigraphy with xenon-133. Of eight patients who had indeterminate scans due to the presence of a single VP mismatch, four were demonstrated to have PE by angiography. Kr-81m is an excellent agent for VP scanning in cases of suspected PE, offering accuracy in diagnosis as well as favorable physical properties.  相似文献   
23.
Eleven cases of migraine with and without aura were investigated with positron emission tomography (PET). Regional cerebral blood flow (rCBF), oxygen metabolism (rCMRO2) and oxygen extraction (rOER) were measured during baseline ( n =11), aura ( n = 6), headache ( n = 10) and after treatment with sumatriptan ( n = 4). Data were analysed using and ROI-based approach from 26 different anatomically defined regions, and also an exploratory approach whereby all subjects were normalized to a stereotactic brain atlas; t -maps were constructed by depicting significant changes between states. The exploratory approach revealed a region corresponding to the primary visual cortex with significant reductions in rCBF (23.1%) and rCMRO2 (22.5%), but no change in rOER during the headache phase compared to baseline. These data suggest that cerebral ischemia was not the primary cause of the attacks in these cases.  相似文献   
24.
Background  Little is known about cross-language measurement equivalence of the job content questionnaire (JCQ) Purpose  The purposes of this study were to assess the extent of cross-language differential item functioning (DIF) of the 27 JCQ items in six languages (French, Dutch, Belgian-French, Belgian-Dutch (Flemish), Italian, and Swedish) from six European research centers and to test whether its effects on the scale-level mean comparisons among the centers were substantial or not. Method  A partial gamma coefficient method was used for statistical DIF analyses where the Flemish JCQ was the reference for other language versions. Additionally, equivalence between the Flemish and Dutch translations was subjected to a judgmental review. Results  On average, 36% to 39% of the total tested items appeared to be cross-language DIF items in the statistical analyses. The judgmental review indicated that half of the DIF items may be associated with translation difference. The impacts of the DIF items on the mean comparisons of the JCQ scales between the centers were non-trivial: underestimated skill discretion (Milan), underestimated decision authority (Leiden), underestimated psychological demands (Milan women), and incomparable coworker support (Gothenburg 95). Conclusion  Cross-language DIF of the JCQ among European countries should be considered in international comparative studies on psychosocial job hazards using JCQ scales.
BongKyoo ChoiEmail:
  相似文献   
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为研究人类染色体17p13.3位点新克隆的基因HC56,HC71和HC90在白血病细胞中的表达,应用同位素标记的、以βM2基因作为内参的半定量RT—PcR法,检测35例急性白血病和4株白血病细胞系的Hc56,Hc70和HC90基因的表达。结果显示,急性淋巴系白血病病人的HC90基因和T淋巴系白血病细胞系Jurkat细胞HC90基因表达水平降低。急性髓系白血病病人HC71基因表达水平降低。HC56基因表达在急性白血病和正常对照间未见显差异。结论:在人类白血病有HC70和HC90的基因表达异常。  相似文献   
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Back ground

Stroke produces a wide range of mental and emotional disorders. Neuropsychiatric complications associated with stroke may have negative effects on the social functioning, overall quality of life and the recovery of motor functioning of stroke survivors.

Objective

To determine the prevalence and nature of psychiatric morbidity among stroke patients attending neurology outpatient clinic of the University of Ilorin Teaching Hospital (UITH), Ilorin-Nigeria.

Methods

All patients with stroke aged 18 years and above at an outpatient neurology clinic in Ilorin, Nigeria were assessed for mental and emotional disorders using the Schedule for Clinical Assessment in Neuropsychiatry (SCAN) over one year (March 2009 to February 2010).

Results

Overall prevalence of psychiatric morbidity was 36.0% (30/83) among 83 patients who constituted the study population. Specific diagnoses recorded were depression (19.2%), generalised anxiety disorder (9.6%), harmful alcohol use (2.4%); dementia, somatoform disorder, phobia and delusional disorder each had a prevalence of 1.2%. Clinical and sociodemographic variables were not significantly associated with psychiatric morbidity.

Conclusion

Psychiatric disorders are often associated with stroke. Identifying and treating stroke patients with these psychiatric co-morbidities could thus help to improve the overall quality of life of these patients.  相似文献   
29.
Abstract— Ecto ATP-diphosphohydrolase (apyrase) activity of human endothelial cells following aspirin treatment has been studied in-vitro. It was shown by HPLC analysis of supernatant samples that pre-incubation of the cultures with aspirin resulted in a significantly increased turnover of supplemented ATP into its degradation products (ADP and AMP). Enhanced expression of ectoenzyme after aspirin treatment could be observed as demonstrated by immunofluorescence-staining with monoclonal anti-apyrase antibodies. This suggests enhancement of endothelial ATP-diphosphohydrolase activity induced by aspirin. The present data obtained in human vascular cells in-vitro are in line with results from previous animal studies in-vivo, suggesting a novel cyclo-oxygenase-independent antithrombotic activity of aspirin.  相似文献   
30.
Early and late synovectomy of the knee in rheumatoid arthritis   总被引:1,自引:0,他引:1  
The results after open knee synovectomy in the treatment of rheumatoid arthritis were investigated in a retrospective study including 44 patients with 55 knees. Median observation time was 73 months. Early synovectomy showed significant pain-relief and improvement of knee function, effusion was reduced and range of motion was unchanged. Total knee alloplasty (TKA) was performed in one knee among the patients who underwent early synovectomy, while reoperation with TKA had been performed in 12 out of 28 knees after late synovectomy. It is concluded that early synovectomy is indicated when medical treatment has failed. Late synovectomy must be regarded as a palliative procedure in order to postpone TKA.  相似文献   
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