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41.
Introduction: Image integration is being used in ablation procedures. However, the success of this approach is dependent on the accuracy of the image integration process. This study aims to evaluate the in vivo accuracy and reliability of the integrated image.
Methods and Results: One hundred twenty-four patients undergoing radiofrequency (RF) ablation catheter ablation for atrial fibrillation (AF) were recruited for this study from three different centers. Cardiac computerized tomography (CT) was performed in all patients and a 3D image of the left atrium (LA) and pulmonary veins (PVs) was extracted for registration after segmentation using a software program (CartoMerge, Biosense Webster, Inc.). Different landmarks were selected for registration and compared. Surface registration was then done and the impact on integration and the landmarks was evaluated.
The best landmark registration was achieved when the posterior points on the pulmonary veins were selected (5.6 ± 3.2). Landmarks taken on the anterior wall, left atrial appendage (LAA) or the coronary sinus (CS) resulted in a larger registration error (9.1 ± 2.5). The mean error for surface registration was 2.17 ± 1.65. However, surface registration resulted in shifting of the initially registered landmark points leading to a larger error (from 5.6 ± 3.2 to 9.2 ± 2.1; 95% CI 4.2–3.05).
Conclusion: Posterior wall landmarks at the PV-LA junction are the most accurate landmarks for image integration in respect to the target ablation area. The concurrent use of the present surface registration algorithm may result in shifting of the initial landmarks with loss of their initial correlation with the area of interest.  相似文献   
42.
To determine the patterns of thyroid dysfunction and autoantibodies associated with SLE and RA patients, twenty patients with SLE and another group of twenty with RA were studied. The results were compared with those of twenty apparently healthy age- and sex- matched controls. All patients were subjected to complete history taking, thorough clinical examination and joint examination. All patients and controls were subjected to the following investigations: T3, T4, TSH, antithyroglobulin antibodies (ATGAb) and thyroid peroxidase antibodies (TPOAb). Also, complete blood picture, ESR, RF, ANA, CRP and LE cells were done. This study revealed that thyroid disorders were significantly increased in SLE patients (50%) when compared to RA (15%) (P<0.05). In SLE group, 20% had euthyroid sick syndrome, 20% had hypothyroidism (10% subclinical and 10% biochemical), and 10% had hyperthyroidism (5% subclinical and 5% biochemical). However, in RA, 10% had hypothyroidism (subclinical) and 5% had subclinical hyperthyroidism. TPOAb was found in 15% of SLE and 5% of RA patients and 10% of controls, but the titres were higher in SLE and RA patients. Also, ATGAb was found in 5% of SLE, 30% of RA patients and 10% of controls, but the titres were higher in SLE and RA patients. It is concluded that thyroid abnormalities are more implicated with euthyroid sick syndrome and hypothyroidism (subclinical and overt) than hyperthyroidism in SLE patients. SLE and RA were associated with antithyroid antibodies (TPOAb in SLE and ATGAb in RA). Performance of thyroid function tests in patients with SLE, in particular and RA as a part of the biochemical and immunological profiles, may help in early detection of associated thyroid disorders.  相似文献   
43.
IntroductionThe aim of this study was to compare the fracture resistance of endodontically treated premolars after the application of three restorative materials (i.e., direct composite, indirect composite, and computer aided design/computer aided manufacturing CAD/CAM ceramic inlays) to restore a conservative occluso-mesial cavity preparation.Materials and methodssixty sound maxillary premolars were divided into four experimental groups; group A: the control group, where neither root canal treatment nor preparation were performed; group B: teeth were restored with a direct Filtek Z250 composite restorative material; group C: teeth were restored with an indirect inlay Filtek Z250 composite restorative material; group D: teeth were restored with IPS E.Max CAD/CAM monolithic ceramic inlays. Access cavities and root canal treatment procedures were conducted using standard techniques. Then, the cavities were restored with direct composite restorative materials following manufacturer’s instructions. Each group received mesial-occlusal cavities and restored according to the designated group.Teeth from all groups were exposed to a thermocycling regimen of 500 cycles in water baths at 5–55 °C. Then, each specimen was mounted on a special fixture on a computer controlled Instron Universal Testing Machine. An axial compressive load was applied to the palatal cusp up to failure at an angle of 45°. The force was applied at the rate of 2 mm/min until visible or audible evidence of fracture was observed. The force at fracture was measured in MPa, and the fracture mode was recorded as either favorable [restorable adhesive fracture above the cemento-enamel junction (CEJ)] or unfavorale (non-restorable fractures under CEJ). The obtained data were analyzed using the SPSS version 21.0 statistical software. One-way ANOVA and Tukey's test were used to compare the mean values of maximum load of the four groups. Pearson's Chi-square test was used to compare the distribution of failure mode among the four groups. The p-value of ≤ 0.05 was used to report the statistical significance of results.  相似文献   
44.
Background: Osteoporosis (OP) is a growing health problem not only in women but also in men. Subjects and methods: This study was carried out on 100 healthy men, age range 30–65 years (mean ± SD, 44.65 ± 8.3). All were randomly recruited from Assiut city during the period January 2005 to January 2006. Complete clinical history included occupational history, smoking habit, physical activity and calcium intake. Complete clinical examination and anthropometric measurments were done. Laboratory investigations for serum calcium, phosphorus and osteocalcin were performed. Bone mineral density (BMD) was measured by calcaneal ultrasound. Results: Sixty‐three percent of participants had normal BMD, 37% had low BMD, (26% had quantitative bone ultrasound [QUS] T‐score –1 to –2.5 and 11% had QUS T‐score ≤ –2.5). Smoking and low physical activity were risk factors for low BMD. Significant positive correlations were found between BMD and body mass index, serum calcium, and osteocalcin and negative correlation with phosphorus. We concluded that low BMD occurs with high frequency in Egyptian men. Smoking, physical inactivity and low body index are significant risk factors. Low serum calcium, low serum osteocalcin and high serum phosphorus are biochemical risk factors of low BMD in males.  相似文献   
45.
AimsTo determine the prevalence of hypertension, control of hypertension and patterns of antihypertensive medications in Malaysian type 2 diabetic patients who attended diabetes clinics in Hospital University Sains Malaysia (Tertiary Hospital).Materials and methodsThe study design was observational prospective longitudinal follow-up study; the study was conducted with sample of 1077 type 2 diabetes mellitus outpatient recruited whom attended the diabetes clinics at Hospital Universiti Sains Malaysia (HUSM) in Kelantan. The study period was from January till December 2008. Blood pressure was defined as >130/80 or use of antihypertension medications. Demographic characteristics of patients, level of blood pressure control, use of antihypertensive medications and patterns of antihypertensive therapy.ResultsThe prevalence of hypertension in Malaysian type 2 diabetic patients was 998 (92.7%),antihypertensive drugs were prescribed in 940 (94.2%) of hypertensive patients with type 2 diabetic mellitus. The achievement of blood pressure control (≤130/80 mmHg) was 471 (47.2%) %. The percentage of patients receiving one, two, three, and four drugs were 253 (25.3%), 311 (31.3%), 179 (17.9%), and 197 (19.7%) respectively. Calcium channel blockers were the most commonly prescribed antihypertensive agents 757 (75.7%) followed by Angiotensin-converting enzyme inhibitors 446 (44.6%), and Angiotensin receptor blockers 42.4 (42.4%).ConclusionThe prevalence of hypertension is high in Malaysian type 2 diabetic patients, hypertension was not controlled to the recommended levels of blood pressure in about one-half (52.8%) of diabetes patients. Calcium channel blockers were the most commonly prescribed antihypertensive agents. There is an urgent need to educate both patients and health care providers of importance of achieving target of treatment in order to reduce morbidity and mortality due to diabetes with hypertension.  相似文献   
46.
47.
Low-glycemic index diets are associated with a wide range of benefits when followed on a chronic basis. The chronic effects, however, of the substitution of 1 meal per day are not well known in diabetic subjects. Therefore, we aimed to evaluate whether the chronic use of a low-glycemic index breakfast (low-GIB) rich in low-GI carbohydrates and a modest amount of soluble fibers could have an effect on lipemia at a subsequent lunch, and improve glucose and lipid metabolism in men with type 2 diabetes. A total of 13 men with type 2 diabetes were randomly allocated in a double-blind cross-over design to a 4-week daily intake of a low-GI versus a high-GI breakfast separated by a 15-day washout interval. The low-GI breakfast was composed of whole grain bread and muesli containing 3 g beta-glucan from oats. Low-GIB induced lower postprandial plasma glucose peaks than the high-GIB at the beginning (baseline, P <.001) and after the 4-week intake (P <.001). The incremental area under the plasma glucose curve was also lower (P <.001, P <.01, baseline, and 4 weeks, respectively). There was no effect on fasting plasma glucose, insulin, fructosamine, or glycosylated hemoglobin (HbA(1c)). Fasting plasma cholesterol, as well as the incremental area under the cholesterol curve, were lower (P <.03, P <.02) after the 4-week low-GIB period than after the high-GIB period. Apolipoprotein B (apo B) was also decreased by the 4-week low-GIB. There was no effect of the low-GI breakfast on triacylglycerol excursions or glucose and insulin responses at the second meal. The high-GIB, however, tended to decrease the amount of mRNA of leptin in abdominal adipose tissue, but had no effect on peroxisome proliferator-activated receptor gamma (PPARgamma) and cholesterylester transfer protein (CETP) mRNA amounts. In conclusion, the intake of a low-GI breakfast containing a modest amount (3 g) of beta-glucan for 4 weeks allowed good glycemic control and induced low plasma cholesterol levels in men with type 2 diabetes. The decrease in plasma cholesterol associated with low-GI breakfast intake may reduce the risk of developing cardiovascular complications in subjects with type 2 diabetes.  相似文献   
48.
Iron deficiency anemia (IDA) is one of the most prevalent micronutrient deficiencies particularly in the developing countries. While there is evidence of an altered immune profile in iron deficiency, the exact immunoregulatory role of iron is not known. Knowledge particularly in children, who are vulnerable to iron deficiency and infection, is lacking. We aimed to study the effects of IDA and its treatment with oral iron supplementation on cell-mediated immunity. The levels of T-lymphocytes, their CD4+, CD8+ and CD1a+ subsets, transferrin receptor (CD71) and serum ferritin were evaluated in 40 iron-deficient and 40 healthy children. The impact of oral iron supplementation for three months on the same parameters was also noted in children with IDA. The level of mature T-lymphocytes (CD4+ and CD8+) was significantly lower (P<0.001) while that of the immature T-cells (CD1a+) was significantly higher (p<0.001) in IDA children compared to the control. The mature T-cell count was significantly improved after iron therapy. In spite of significant reduction in the immature T-cells (CD1a+) level after iron supplementation, it was significantly higher than the control. The present study demonstrated that T-lymphocytes maturation was defective in IDA and improved partially after 3 months of iron supplementation. Therefore, longer time of iron therapy may be required to induce complete maturation of T-lymphocytes.  相似文献   
49.
50.
Clinical Rheumatology - The prevalence of sarcopenia with osteoporosis results in a higher risk of falling and fractures. It was noted that patients who had completed their planned 5-year denosumab...  相似文献   
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