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Cardiac myxomas (CM) is by far the most common type of primary cardiac neoplasm that commonly arise within the left atria and is composed of primitive connective tissue cells and stroma. Despite the benign nature, the CMs are often surgically removed because they can lead to severe complications. Large, thin, and hypermobile forms are unusual. The frequency of recurrence is about 22% for complex forms and 12% for other familial forms and 1% to 3% for sporadic myxomas, which seldom recur after surgery. Although transesophageal echocardiography shows usually accurate imaging capabilities to detect the myxoma, further imaging methods including computed tomography, cardiovascular magnetic resonance imaging, and 18F-fluorodeoxyglucose positron-emission tomography/computed tomography may be useful to diagnosis for it. Surgery is the mainstay of treatment  相似文献   
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X linked adrenoleukodystrophy (X-ALD) is a neurodegenerative disease characterized by progressive demyelination of the central nervous system, adrenocortical insufficiency and elevated levels of very long chain fatty acids (VLCFAs). It is caused by mutations in ABCD1 gene located at Xq28. More than 1,300 mutations have been identified to date which is unique to each patient. In this study we report the mutational analysis of 2 X-ALD patients (1 male and 1 female) showing variable clinical spectrum. The mutation analysis of the female patient revealed IVS5-6delC (c.1489-6delC) and p. P543L variations in compound heterozygous state. The male patient was found to be hemizygous for a novel mutation, p. R104P. In conclusion, while defining a novel mutation, the cases presented herein may contribute to the mutation and clinical spectrum of X-ALD.  相似文献   
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In this study, the psychological effects of single-dose corticosteroids administered to patients who had undergone rhinoplasty were assessed. A total of 30 rhinoplasty patients were included in the study and were randomly assigned to 1 of 2 groups. Preoperatively, patients completed the Bech Rafaelsen Mania Scale and the Beck Depression Inventory. Dexamethasone 10 mg was given intravenously just before surgery to the first group, but no medication was administered to the second group. On the first postoperative day, patients were seen again, and the Bech Rafaelsen Mania Scale and the Beck Depression Inventory were again completed. Periorbital edema and ecchymosis were graded, and psychological well-being was measured on a standard visual analog scale. All patients and physicians were blinded to treatment until the end of the study. Results show that administration of a single-dose of dexamethasone 10 mg caused neither euphoria nor depression. No significant differences were observed between steroid and control groups in terms of patients’ psychological well-being. With single-dose dexamethasone, periorbital edema was significantly reduced on the first 2 postoperative days, and upper eyelid ecchymosis was significantly decreased only on the first postoperative day. However, preoperative steroid administration had no influence on ecchymosis of the lower eyelid. The authors conclude that single-dose dexamethasone 10 mg can be used safely to reduce periorbital edema and ecchymosis in rhinoplasty patients.  相似文献   
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OBJECTIVE: Hypotension induced by tricyclic antidepressants is multifactorial. Previous animal experiments suggest a contribution from nitric oxide production. Our study aimed to evaluate the role of nitric oxide in amitriptyline-induced hypotension using N-nitro-L-arginine methyl ester, a nitric oxide synthesis inhibitor, and 3-morpholino sydnonimine, a nitric oxide donor, in anesthetized rats. METHODS: Amitriptyline intoxication was induced by the continuous infusion of amitriptyline 0.625 mg/kg/min throughout the experiment in anesthetized rats. Fifteen and 25 minutes after amitriptyline infusion began, two bolus doses of 10 mg/kg of N-nitro-L-arginine methyl ester (n = 8) or an equivalent volume of 5% dextrose solution (n = 8) was administered to each rat (Protocol 1). To investigate whether the effect of N-nitro-L-arginine methyl ester on blood pressure is counteracted by 3-morpholino sydnonimine, after the same protocol of amitriptyline infusion and 5 minutes after an N-nitro-L-arginine methyl ester bolus, a bolus of 3000 nmol/kg of 3-morpholino sydnonimine was administered (n = 8) to each rat (Protocol 2). To investigate the effect of N-nitro-L-arginine methyl ester on 3-morpholino sydnonimine induced hypotension, a group of rats received a continuous infusion of 0.54 mg/kg/h of 3-morpholino sydnonimine until 50% reduction was observed in mean arterial blood pressure followed by a bolus dose of 10 mg/kg of N-nitro-L-arginine methyl ester (n = 6) or 5% dextrose solution (n = 6) (Protocol 3). Outcome measures included mean arterial blood pressure, heart rate, and QRS duration in electrocardiogram. Student's t test and survival analysis were used for selected comparisons. RESULTS: For all parameters, the treatment groups were similar at baseline and at postamitriptyline periods before therapy was rendered. Amitriptyline infusion significantly reduced mean arterial blood pressure by 50.8 +/- 2.2% and prolonged QRS by 23.9 +/- 7.2% after 15 minutes. In Protocol 1, N-nitro-L-arginine methyl ester significantly increased mean arterial blood pressure compared to dextrose-treated control animals within 30 minutes (77.9 +/- 8.5% vs. 49.7 +/- 5.0% mmHg, p < 0.01, 95% CI 57.1-98.7%). QRS duration progressively increased during the amitriptyline infusion; however, there was no significant difference in QRS width between N-nitro-L-arginine methyl ester and control groups at any time point. N-nitro-L-arginine methyl ester increased survival time compared to controls (33.4 +/- 4.1 vs. 19.9 +/- 2.7 minutes, p < 0.01, 95% CI 25.4-41.3) but did not affect mortality. In Protocol 2 of continuous infusion of amitriptyline, 3-morpholino sydnonimine counteracted the N-nitro-L-arginine methyl ester-induced increase in mean arterial blood pressure. In both protocols, heart rate decreased significantly during amitriptyline infusion but there was no difference between treatment and control groups. In Protocol 3, N-nitro-L-arginine methyl ester bolus reversed 3-morpholino sydnonimine-induced hypotension compared to dextrose bolus. (83.8 +/- 5.7% vs. 54.6 +/- 4.8%, p < 0.01, 95% CI 69.2-98.4). CONCLUSION: N-nitro-L-arginine methyl ester is found to be effective in temporarily improving hypotension and prolonging survival time but does not affect overall mortality. Because this effect was antagonized by 3-morpholino sydnonimine, nitric oxide production appears to contribute to the pathophysiology of amitriptyline-induced hypotension.  相似文献   
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Inactivation of the E-cadherin system by multiple mechanisms, including both genetic and epigenetic events, plays a significant role in multistage carcinogenesis. We have investigated the effects of sinusoidal electromagnetic fields (SMF) on E-cadherin expression in an MNU (N-methyl-N-nitrosurea)-induced colon tumor model. Male wistar albino rats were used for the study. The rats were classified into four groups: I (MNU), II (SMF+MNU), III (SMF) and IV (control). After administered at MNU in 1st and 2nd groups, 2nd and 3rd groups were exposed to a sinusoidal magnetic field (SMF, 50 Hz, 5 mT) for 6 hours/day for 8 months. The expression of E-cadherin were examined in four groups of rat colon tissues by immunohistochemistry on paraffin sections. For immunohistochemical analysis, the labeled streptavidin biotin method was performed using a Vectastain Universal Quick Kit with microwave accentuation. Fisher's exact test was used for statistical analysis between proportions. Immunohistochemical studies of E-cadherin expression in this model demonstrated significant differences for cytoplasmic expression pattern. These results suggest that the electromagnetic fields result in significant alterations in cell adhesion mechanisms. This study has implications for understanding the role of fields in cell detachment in cancer metastasis. Further work is required to determine the relative effect of the magnetic fields on these phenomena.  相似文献   
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Objective: Cigarette smoking is one of the major risk factors for coronary artery disease. However, chronic smoking has additional cardiac adverse effects independent of coronary atherosclerosis. We assessed the possible effects of chronic smoking on left and right ventricular (LV, RV) long-axis function using Doppler myocardial imaging (DMI). Methods: Forty otherwise healthy smokers (mean age = 26 ± 3 years) and 40 age-matched nonsmoking controls enrolled. Standard echocardiography protocol was followed by DMI. Peak systolic (VS), early (VE) and late diastolic (VA) velocities, peak systolic strain (S), and strain rate (SR) were measured from septal, lateral, and RV free walls. Results: The baseline characteristics of two groups were similar. There were significant differences regarding Doppler myocardial velocity, S, and SR indices. Septal VE (P < 0.04), S (P < 0.0001) and SR (P < 0.02) were significantly reduced in smokers. For both lateral and RV free wall, VS (P < 0.003, P < 0.002, respectively), VE (P < 0.0001, P < 0.002, respectively), S (P < 0.0001 for both), and SR (P < 0.0001, P < 0.002, respectively) were significantly reduced in smokers. There were significant correlations between the amount of smoking and septal, lateral, and RV free wall S and SR. Conclusions: Chronic cigarette smoking causes alterations in long-axis systolic and diastolic functions of right and left ventricles in healthy young subjects. These changes can be accurately detected with Doppler myocardial velocity and SR imaging.  相似文献   
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Purpose: This study investigated the antioxidant effects of whortleberry against cisplatin-induced nephrotoxicity in rats.

Material and methods: This study included 48 female Sprague–Dawley rats weighing 263.68?±?8.29?g. The rats were divided into the following six groups, with eight rats in each group: control, ethanol control, whortleberry control, cisplatin control, 16?mg/kg cisplatin +100?mg/kg whortleberry, and 16?mg/kg cisplatin +200?mg/kg whortleberry groups. Biochemical analysis was performed by measuring total oxidant status and total antioxidant status, histopathological analysis was performed by calculating proximal and distal tubule areas (μm2), and immunohistochemical analysis was performed by determining anti-Caspase-3 immunostaining. Differences among the groups were examined using one-way analysis of variance, and p?Results: Cisplatin treatment decreased the total antioxidant status and increased the total oxidant status and Caspase-3 level. Moreover, it resulted in the dilatation, vacuolization and loss of tubular epithelial cells; and glomerular degeneration and edema in the kidney tissues (p?p?Conclusions: Our results indicate that the antioxidant effects of the whortleberry decrease cisplatin-associated nephrotoxicity.  相似文献   
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