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31.
We have conducted a hospital-based case-control study on 157patients with newly diagnosed myocardial infarction and 157hospital controls. All were men, 35–69 years old and non-smokersor ex-smokers of at least 6 months. A clearcut inverse dose-responserelationship was found between alcohol intake (chiefly red wine)and risk of Ml (odds ratios were 0.69, 0.43 and 0.42, for thosedrinking 1–30, 30–90 and >90 drinks per month,compared to <1). Adjustment by coronary risk factors in logistic-regressionmodels increased the strength of the association with alcohol.Protection was somewhat stronger than in studies conducted incountries where the consumption of beer or liquors is heavierthan that of wine. The protective effect might be due to theantioxidant properties of phenolic substances contained in redwine.  相似文献   
32.
International Journal of Paediatric Dentistry 2011; 21: 50–57 Background. Dental erosion is a multifactorial disease and is associated with dietary habits in infancy and adolescence. Aim. To investigate possible associations among dental erosion and diet, medical history and lifestyle habits in Brazilian schoolchildren. Design. The sample consisted of a random single centre cluster of 414 adolescents (12‐ and 16‐years old) of both genders from private and public schools in Bauru (Brazil). The O’Brien [Children’s Dental Health in the United Kingdom, 1993 (1994) HMSO, London] index was used for dental erosion assessment. Data on medical history, rate and frequency of food and drinks consumption, and lifestyle habits were collected by a self‐reported questionnaire. Odds ratios with 95% confidence intervals were used to assess the univariate relationships between variables. Analysis of questionnaire items was performed by multiple logistic regression analysis. The statistical significance level was set at 5%. Results. The erosion present group comprised 83 subjects and the erosion absent group 331. There were no statistically significant correlations among dental erosion and the consumption of food and drinks, medical history, or lifestyle habits. Conclusion. The results indicate that there was no correlation between dental erosion and the risk factors analysed among adolescents in Bauru/Brazil and further investigations are necessary to clarify the multifactorial etiology of this condition.  相似文献   
33.
Aim: Hypertension is common in haemodialysis (HD) patients. Determining the most appropriate method of blood pressure (BP) measurement, representative of target organ damage, is still an issue. BP variations between pre‐ and post‐HD treatment, or between on‐dialysis day and off‐dialysis day, are common. The aim of this study was to examine the possible differences between pre‐HD office BP (OBP) levels, inter‐HD (iHD) or HD day 24 h ambulatory BP measurement (ABPM) with 48 h ABPM, where the latter was considered the gold standard. Methods: 163 HD patients were studied. BP was monitored consecutively for 48 h with a Takeda TM2421 device, then sub‐analysed into two periods of 24 h: HD and iHD day. An average of 12 sessions pre‐HD OBP measurements was determined. Results: OBP significantly overestimates systolic (SBP) and diastolic BP (DBP) when compared with 48 h ABPM. SBP and DBP are significantly higher on iHD day than on HD day: 141.2 ± 20.8 versus 137.9 ± 20.9, and 77.1 ± 11.1 versus 76.1 ± 10.9 (P < 0.01). No differences of SBP night/day ratio were reported between 48 h ABPM and iHD 24 h ABPM or HD 24 h ABPM. The highest correlations were reported between 48 h SBP/DBP with iHD or HD 24 h ABPM (r2 = 0.95, P < 0.001), while the lowest between 48 h SBP/DBP and OBP (r2 = 0.40, P < 0.01, r2 = 0.12, P < 0.01). The narrowest limits of agreement using the Bland and Altman test were reported between 48 h SBP or DBP and 24 h iHD or HD day ABPM. Considering 48 h ABPM, 80.5% of patients had BP higher than the norm, compared with 61.7% of patients in the case of OBP (χ2 = 13.28, P < 0.001). The sensibility for detecting hypertension for iHD day 24 h ABPM was 98.4%, with specificity of 90%. The sensibility of 24 h HD day ABPM was 90.3%, with specificity 96.6%. In the case of OBP, sensibility and specificity were considerably lower, that is, 72.6% and 83.3% respectively. Conclusion: Significant differences are shown between OBP and 48 h ABPM in the recognition of a hypertensive state. OBP measurement has a lower sensibility and specificity than 24 h ABPM, which remains a valid alternative approach to 48 h ABPM in HD patients. Errors of OBP estimation should be taken into account, with possible negative impact on treatment strategies and epidemiology studies.  相似文献   
34.
Introduction: Spatial characteristics of atrial fibrillatory waves have been extracted by using a vectorcardiogram (VCG) during atrial fibrillation (AF). However, the VCG is usually not recorded in clinical practice and atrial loops are derived from the 12-lead electrocardiogram (ECG). We evaluated the suitability of the reconstruction of orthogonal leads from the 12-lead ECG for fibrillatory waves in AF.
Methods: We used the Physikalisch-Technische Bundesanstalt diagnostic ECG database, which contains 15 simultaneously recorded signals (12-lead ECG and three Frank orthogonal leads) of 13 patients during AF. Frank leads were derived from the 12-lead ECG by using Dower's inverse transform. Derived leads were then compared to true Frank leads in terms of the relative error achieved. We calculated the orientation of AF loops of both recorded orthogonal leads and derived leads and measured the difference in estimated orientation. Also, we investigated the relationship of errors in derivation with fibrillatory wave amplitude, frequency, wave residuum, and fit to a plane of the AF loops.
Results: Errors in derivation of AF loops were 68 ± 31% and errors in the estimation of orientation were 35.85 ± 20.43°. We did not find any correlation among these errors and amplitude, frequency, or other parameters.
Conclusions: In conclusion, Dower's inverse transform should not be used for the derivation of orthogonal leads from the 12-lead ECG for the analysis of fibrillatory wave loops in AF. Spatial parameters obtained after this derivation may differ from those obtained from recorded orthogonal leads.  相似文献   
35.
Abstract: A child was diagnosed with onychomycosis before he was 2 months of age; however, he had noticeable nail lesions from the second week of life.  相似文献   
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37.
Summary. This study describes the clinical phenotype of the C?→? T mutation at position – 92 of the β-globin gene. Excluding two cases with HbA2 levels within the range of the /3-thalassaemia carrier state, heterozygotes for this mutation showed normal or borderline red blood cells count, Hb levels, MCV, MCH and HbA2 values, and unbalanced globin chain synthesis. Compound heterozygotes for the - 92 C → T mutation and a β° thalassaemia mutation (β°39) (two cases) or severe β-thalassaemia (p+ IVSII nt 745) (two cases) developed thalassaemia intermedia. According to these characteristics, the –92 promoter mutation should be added to the list of silent β-thalassaemias.  相似文献   
38.
39.
Background: Electrical storm due to recurrent ventricular tachycardia (VT) in patients with implantable cardioverter defibrillator (ICD) can adversely affect their long‐term survival. This study evaluates the efficiency of the radiofrequency catheter ablation of electrical storm due to monomorphic VT in patients with idiopathic dilated cardiomyopathy (DCM) and assesses its long‐term effects on survival. Methods and Results: Between April 2004 and October 2008, 13 consecutive patients (nine men, mean age 56.8 ± 17.8 years) with DCM and electrical storm due to monomorphic VT who had ICD underwent 17 catheter ablation procedures, including four epicardial, at our center. Acute complete success was defined as the lack of inducibility of any VT at the end of procedure during programmed right ventricular stimulation and was achieved in eight patients (61.5%). During a median follow‐up of 23 months (range 3–63 months) nine patients (69%) were alive and eight patients (61.5%) were free from VT recurrence. Among those with acute complete (n = 8) and partial (n = 5) success, seven patients (87.5%) and one patient (20%) were free from any VT recurrence and ICD therapy, respectively (P = 0.025). Among those with acute complete and partial success, seven patients (87.5%) and two patients (40%) were alive, respectively (Mantel‐Cox test P = 0.082). Among those who had an initially failed endocardial ablation (n = 8), four underwent further epicardial ablation that was completely successful in three patients (75%). Conclusion: Catheter ablation in patients with DCM and electrical storm due to monomorphic VT who had an ICD prevents further VT recurrence in 61.5% of the patients. Complete successful catheter ablation may play a protective role and was associated with reduced mortality during the follow‐up period. More aggressive ablation strategies in patients with initially failed endocardial ablation might improve the long‐term survival of these patients; however, further studies are needed to clarify this issue. (PACE 2010; 33:1504–1509)  相似文献   
40.
Objective: To measure, in intact closed chest, the pressure in the pulmonary microvasculature during transition to mild interstitial edema. Methods: In anesthetized spontaneously breathing rabbits, the pulmonary artery and left atrium were cannulated. Pleural windows were prepared to view the superficial pulmonary microvascular network through the intact parietal pleura. After intravenous infusion of 96.4 ± 12.3 ml of saline at a rate of 0.5 ml/kg h, the hydraulic pressure in the pulmonary microvessels (15–240 μm in diameter) were measured using glass pipettes driven through the pleural window and connected to a servonull system. Results: After saline, plasma protein concentration decreased from 6 ± 1 to 4.8 ± 0.5 g/dl; pulmonary arterial and left atrial pressures averaged 22.3 ± 6.4 and 2.3 ± 2 cm H2O in control and 23.1 ± 4.2 and 4.2 ± 2 cm H2O after infusion. After saline loading, 16.4% of total pressure drop occurred from pulmonary artery to 80-μm arterioles, 60.3% in 30–80-μm arterioles, 6.9% from 30-μm arterioles to 30-μm venules and 16.4% in the downstream segment. Conclusions: Mild interstitial edema induced, with respect to control, constriction of small arterioles and capillary recruitment to maintain a low capillary pressure. Hence, in initial edema, pulmonary circulation prevents further fluid filtration, acting like an intrinsic safety factor to delay development of severe edema.  相似文献   
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