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71.
Objective: The aim of this study was to evaluate whether exposure to second-hand smoke affected the six-minute walk test (6MWT) of obese non-asthmatic pediatric cases.Methods: Obese pediatric patients (body mass index >95th p) with no existing co-morbidities were included in the study. Smoke exposure was assessed with a self-reported questionnaire completed by the parents. The subjects were divided into two groups: Group 1 consisting of obese children exposed to passive smoking and Group 2 of obese children not exposed to passive smoking. In addition to 6MWT, spirometric flow and volume, including forced expiratory volume in 1 s and peak expiratory flow rate, were also measured in all subjects. The results of the 6MWT were assessed to determine any association with passive smoking.Results: The study included 75 obese pediatric cases (40 male, 35 female) with a mean age of 9.06±0.97 years. The 6MWT results in Group 1 was 501.88±62.12 meters and in Group 2 559.63±72.93 meters. The difference was statistically significant (p=0.001).Conclusions: Passive smoking may negatively affect the respiratory and cardiovascular capacity in obese children, who are already at risk of lower cardiopulmonary function. The evaluation of 6MWT in these pediatric patients may be useful for monitoring and families should be warned about potential problems due to smoking.  相似文献   
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Reviews in Endocrine and Metabolic Disorders - Endocrine Disrupting Chemicals (EDCs) are a global problem for environmental and human health. They are defined as “an exogenous chemical, or...  相似文献   
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Apelin has been identified as an endogenous ligand of the orphan G-protein-coupled apelin receptor (APJR). These receptors are widely expressed in the central nervous system and periphery and play a role in the regulation of fluid and glucose homeostasis, feeding behavior, vessel formation, cell proliferation and immunity. We aimed to investigate whether water immersion and restraint stress have effects on apelin and APJR expression and apoptosis in heart tissue of male Wistar rats. The cardiac tissues were obtained from control, water immersion and restraint stress (WIRS) and apelin antagonist (F13A) + WIRS groups of rats and embedded in paraffin wax. Immunohistochemical staining methods were used to localize apelin, APJR and TUNEL immunopositive cells. H-SCORE was used for semi-quantitative determinations. Apelin protein levels were determined by Western blot in the cardiac tissues and plasma corticosteroid levels were measured by enzyme immunoassay (EIA). Apelin immunolocalization was found especially in endothelial cells and mast cells and faintly in cardiomyocytes, APJR immunostaining was shown in endothelial cells and cardiomyocytes, and TUNEL reaction was observed in endothelial cells and in some fibroblasts. Apelin expression was significantly increased in the WIRS and F13A + WIRS groups compared to the control group. The APJR reaction was similar in all groups. The number of TUNEL-positive cells was significantly higher in the F13A + WIRS group than that of the control group. Our study showed that WIRS for 6 h increased plasma corticosterone levels and cardiac apelin expression in rats. The increased levels of apelin inhibited stress-induced apoptosis in heart. These results may be important for the therapeutic approach to a variety of stress-related heart disease.  相似文献   
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Spontaneous coronary artery dissection (SCAD) is a rare disease that is usually seen in young women in left descending coronary artery and result in events like sudden cardiac death and acute myocardial infarction. A 70-year-old man was admitted to the emergency department with chest pain which started 1 h ago during a relative’s funeral. The initial electrocardiography demonstrated 2 mm ST-segment depression in leads V1-V3 and the patient underwent emergent coronary angiography. SCAD simultaneously in two different coronary arteries [left anterior descending (LAD) artery and left circumflex (LCx)] artery was detected and SCAD in LCx artery was causing total occlusion which resulted in acute myocardial infarction. Successful stenting was performed thereafter for both lesions. In addition to the existence of SCAD simultaneously in two different coronary arteries, the presence of muscular bridge and SCAD together at the same site of the LAD artery was another interesting point which made us report this case.  相似文献   
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Atrial fibrillation (AF), which is the most common cardiac arrhythmia, may cause serious symptoms and impair quality of life.1 The development of AF is associated with many risk factors, including age, male gender, hypertension, heart failure, valvular disease, diabetes mellitus (DM) and left atrial (LA) enlargement.2-4 Electrical and/or mechanical remodelling of the atria is thought to be a pathophysiological characteristic of AF.5The pregnant state may be pro-dysrhythmic. This is related to the cardiovascular, hormonal, haemodynamic and autonomic changes during healthy pregnancy. Levels of oestrogen and β-human chorionic gonadotropin increase dramatically. Haemodynamic changes include an increase in circulating blood volume, which increases cardiac output. This results in myocardial stretch and an increase in cardiac end-diastolic volume. High plasma catecholamine concentrations and adrenergic receptor sensitivity increase sympathetic tone. All these changes in pregnant women may make them more prone to dysrhythmogenesis.6Most pregnant women complain of palpitations, dizziness and even syncope, but these symptoms are rarely associated with cardiac dysrhythmias. AF is the most common clinically significant cardiac arrhythmia in the general population but it is rarely seen in pregnant women. When it occurs, it can represent a benign, self-limited lone episode of AF or may be secondary to congenital or rheumatic valvular disease, hypertrophic cardiomyopathy, thyroid disease, or pre-excitation syndrome.Two simple electrocardiogram (ECG) markers, namely maximum P-wave duration (Pmax) and P-wave dispersion (PD), have been used to evaluate intra- and inter-atrial conduction times and the inhomogeneous propagation of sinus impulses, which are well-known electrophysiological characteristics of the atrium prone to fibrillation.7,8 Prolonged Pmax and PD have been reported to represent an increased risk for AF in patients with no underlying heart disease.7,8 Besides, evidence from laboratory and epidemiological research suggests that systemic inflammation may play a role in AF aetiology.9 It has also been demonstrated that atrial electromechanical coupling, measured by tissue Doppler imaging (TDI), as significantly longer in patients with paroxysmal AF than in control groups.10,11To our knowledge, no study evaluating PD and atrial electromechanical coupling has been investigated in pregnant subjects without additional systemic disease. Therefore, in this study we aimed to examine atrial electromechanical coupling and PD, reflecting inter-atrial conduction times in pregnant subjects.  相似文献   
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Objectives: The aim of this study was to compare in vitro root fracture resistance following root canal filling with AH 26 using lateral condensation, BeeFill, and Thermafil techniques. Study Design: Eighty extracted human mandibular premolars with similar dimensions were selected. In order to standardize the roots, measurements were taken in two separate regions of the teeth—at the cemento-enamel junction and 8 mm apically from the junction—buccolingual as well as mesiodistal for every tooth. Teeth were then randomly divided into five groups (n=16). With the exception of the non-prepared group (Group 1), instrumentation was done in all groups. In group 2, instrumentation but no filling was performed; in group 3, the obturation was done with AH 26 + gutta-percha; in group 4, with AH 26 + BeeFill and in group 5, AH 26 + a Thermafil obturator was used. All the roots were mounted vertically in copper rings and filled with acrylic resin, exposing 8 mm of the coronal part. A universal testing machine was used for the strength test. Results: The results were analyzed using the one-way ANOVA test. The significance between the groups was tested with Temhane’s T2 test. The results indicate that instrumentation of root canals had a significant effect on fracture resistance (p<0.05). In addition, there were no differences between the root canal obturation techniques; furthermore, these techniques did not create a statistically important resistance to vertical fracture (p>0.05). Conclusions: The results suggest that instrumentation of root canals significantly weakens the tooth structure to fracture and the root canal obturation techniques that are used are not able to form reinforcement. Key words:AH 26, obturation technique, vertical fracture.  相似文献   
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