1,721,016 research outputs found
Predictive clustering learning algorithms for stroke patients discharge planning
No full textStroke patients discharge planning is a complex task that could be carried out by the use of a suitable decision support system. Such a platform should be based on unsupervised machine learning algorithms to reach the best results. More specifically, in this kind of prediction task clustering learning algorithms seem to perform better than the other unsupervised models. These algorithms are able to independently subdivide the treated clinical cases into groups, and they can serve to discover interesting correlations among the clinical variables taken into account and to improve the prediction accuracy of the treatment outcome. This work aims to compare the prediction accuracy of a particular clustering learning algorithm, the Growing Neural Gas, with the prediction accuracy of other supervised and unsupervised algorithms used in stroke patients discharge planning. This machine learning model is also able to accurately identify the input space topology. In other words it is characterized by the ability to independently select a subset of attributes to be taken into consideration in order to correctly perform any predictive task
Left ventricular hypertrophy and diastolic dysfunction in alcohol-associated hypertension
No full text: In order to assess left ventricular structure and diastolic function, 50 hypertensive male subjects, 25 with and 25 without a history of alcohol abuse, and 20 normotensive male controls underwent Doppler echocardiographic examination followed by ambulatory blood pressure monitoring for 24 hours. Left ventricular mass was significantly higher in alcoholic hypertensives in relation to non-alcoholic hypertensives (p < 0.05) and normotensive controls (p < 0.001). Moreover, Doppler parameters expressing left ventricular filling pattern were significantly worse in alcoholic than in non-alcoholic hypertensives (p < 0.01). Clinic and ambulatory blood pressure were similar in alcoholic and non-alcoholic hypertensives, while mean day-time heart rate was significantly higher in alcoholics (p < 0.01). Collected data suggest that non-hemodynamic factors are probably involved in the development of cardiovascular abnormalities in hypertensive alcoholics, and that echocardiography should be employed for risk-profile definition in alcohol-associated hypertension
Prevalence of silent ST segment depression during long-term ambulatory electrocardiographic monitoring in asymptomatic diabetic patients with essential hypertension
No full text: Thirty-five asymptomatic diabetic patients with non insulin-dependent diabetes and mild moderate essential hypertension (18 males and 17 females, mean age 60 +/- 6 years) underwent echocardiographic examination, followed by simultaneous ambulatory blood pressure and electrocardiographic monitorings. Three hundred and sixteen significant episodes of asymptomatic ST segment depression (at least 1 mm 80 msec after the J point, lasting more than 1 min) were recorded in 21 patients (60%) with a total duration of 5637 minutes. Patients with asymptomatic episodes of ST segment depression had significantly higher values of total cholesterol (p < 0.05), LDL cholesterol (p < 0.05), Glycosylated hemoglobin (p < 0.001), left ventricular mass index (p < 0.02), mean 24-hour systolic and diastolic ambulatory blood pressure (p < 0.001), systolic (p < 0.02) and diastolic (p < 0.01) ambulatory blood pressure variability and hypertensive peaks (p < 0.05), with respect to the rest of the study population. The number of ST segment depression episodes was significantly related to total cholesterol levels (r = 0.40, p < 0.05), LDL cholesterol levels (r = 0.36, p < 0.05) glycosylated hemoglobin levels (r = 0.50, p < 0.01), left ventricular mass index (r = 0.48, p < 0.01), ambulatory systolic (r = 0.43, p < 0.01) and diastolic (r = 0.51, p < 0.01) blood pressure variability and hypertensive peaks (r = 0.50, p < 0.01). Our data suggest that haemodynamic and metabolic factors could have a relevant role in high prevalence of SMI in asymptomatic diabetic patients with EH. The evidence of SMI in these patients warrants further diagnostic work-up and prognostic assessment
Cumulative exercise-induced left ventricular systolic and diastolic dysfunction in hypertrophic cardiomyopathy.
No full textThe phenomenon of cumulative exercise-induced left ventricular function impairment was studied in 40 patients with non-obstructive hypertrophic cardiomyopathy with resting normal left ventricular function and no increase in ejection fraction on exercise. All patients underwent two symptom-limited exercise tests one-hour apart. Cumulative myocardial dysfunction was seen in 13 patients (group I) but not in the remaining 27 patients (group II). During follow-up, group I showed more commonly than group II a deterioration in symptoms (67% vs 22%, P=0.025) and left ventricular function (50% vs 9%, P=0.019). In conclusion, cumulative exercise-induced myocardial dysfunction can occur in hypertrophic cardiomyopathy and may be associated with clinical deterioration and worse outcome
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Virulent strains of Helicobacter pylori and vascular diseases: A meta-analysis
No full textBackground Cytotoxin-associated gene A (CagA)-positive strains of Helicobacter pylori are an etiological factor for peptic ulcer and gastric cancer. Studies on the role of these virulent strains in vascular diseases yield conflicting results. Methods We searched the MEDLINE database for relevant studies. Meta-analysis was performed using the random effects method. Results We found 10 retrospective case-control studies (with 1527 case patients and 1661 control subjects) and 3 prospective cohort studies (with 701 case patients and 1439 control subjects) on CagA status and ischemic heart disease and 4 retrospective case-control studies (with 513 case patients and 590 control subjects) on CogA status and cerebral ischemia. In the case-control studies, an association of ischemic heart disease with CagA-positive strains (OR 1.87, 95% CI 1.46-2.40) but no significant association with CagA-negative strains (OR 1.15, 5% CI 0.83-1.60) has been found; in the 3 prospective studies, association with ischemic heart disease was weaker but still significant (OR 1.26, 95% Cl 1.05-1.51). In the 4 case-control studies, CagA-positive strains were significantly associated with cerebral ischemia (OR 2.43, 95% Cl 1.89-3.13), again with no association for CagA-negative strains. Conclusions We found a small but significant association between vascular diseases and virulent CagA-positive strains of H. pylori. The lack of association with CagA-negative strains further supports the hypothesis of an independent relationship between virulent strains of H. pylori and vascular diseases. The magnitude of the association with cerebral ischemia needs to be confirmed by prospective studies
Endothelial progenitor cells in patients with coronary artery disease and left ventricular dysfunction
No full textRandomized trial of atorvastatin for reduction of myocardial damage during coronary intervention - Results from the ARMYDA (Atorvastatin for Reduction of MYocardial Damage during Angioplasty) study
No full text
- …
