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We investigated the cytoprotective effect of melatonin in epirubicin-induced cardiotoxicity using four experimental groups of male Wistar rats: untreated control rats, epirubicin-treated rats, epirubicin+melatonin-treated rats, and melatonin-treated rats. We examined the histopathological and biochemical effects of melatonin on the epirubicin-induced changes and measured the levels of the lipid peroxidation end-product (malondialdehyde, MDA), an indicator of nitric oxide (NO) synthesis (nitrite/nitrate production), and reduced glutathione (GSH) in the heart. We also studied the extracellular matrix components (fibronectin, laminin) in the heart. Vacuole formation, mitochondrial deformation and degeneration, and disordered myofibrillary structures were detected ultrastructurally in the epirubicin-treated group. The degeneration was reduced in the heart tissues of the epirubicin+melatonin group. Epirubicin increased the nitrite/nitrate production, but did not change the MDA and GSH levels significantly. Melatonin treatment lowered the nitrite/nitrate concentrations, while increasing the GSH levels, which exceeded the levels in epirubicin+melatonin-treated rats. We conclude that the epirubicin increased the nitrozative stress, not the oxidative stress, in heart tissue, and the cardioprotective effect of melatonin was partially attributed to the suppression of epirubicin-induced nitrozative stress. These results suggest that melatonin partially protects against epirubicin-induced cardiotoxicity.  相似文献   
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A 47‐year‐old male presented to our clinic with complaints of mass in both breasts. In the patient's history, he had undergone low anterior resection for rectum mucinous adenocarcinoma 2 years ago. The masses in both breasts of the patient were excised. Mucinous adenocarcinoma metastases were reported in the pathologic evaluation of the masses. Metastasis should be considered in patients with bilateral breast mass and previously diagnosed cancer even if the patient is male.  相似文献   
85.
Context: Scorzonera L. species (Asteraceae) are edible and as medicinal plants are used for various purposed in folk medicine.

Objective: The methanol extracts of the aerial parts and roots from 27 Scorzonera taxa were investigated for their possible neurobiological effects.

Materials and methods: Inhibitory potential of the Scorzonera species was tested against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase (TYRO) at 100?µg?mL?1 using ELISA microtiter assay. Antioxidant activity of the extracts was tested with radical scavenging activity, metal-chelation capacity, ferric- (FRAP), and phosphomolibdenum-reducing antioxidant power (PRAP) assays. Chlorogenic acid, hyperoside, rutin, and scorzotomentosin-4-O-β-glucoside were also screened in the same manner. Total phenol and flavonoid quantification in the extracts were determined spectrophotometrically.

Results: The aerial parts of Scorzonera pisidica (40.25?±?0.74%) and chlorogenic acid (46.97?±?0.82%) displayed the highest TYRO inhibition, while the remaining samples showed only trivial inhibition against cholinesterases (2.08?±?1.35%–25.32?±?1.37%). The same extract of S. pisidica was revealed to be the most potent in scavenging of all three radicals and FRAP assay.

Discussion and conclusion: Out of 27 taxa, S. pisidica, in particular, may deserve further investigation for its neuroprotective potential.  相似文献   
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OBJECTIVE: Postural phenomena, cardiac arrhythmias and autonomic dysfunction are responsible for presyncope and syncope in patients with mitral valve prolapse (MVP). In this study, arrhythmia and vasovagal syncope incidence were investigated in children with MVP. METHODS: Between April 2005 and December 2006, 37 children with MVP and 26 healthy children were evaluated.Telecardiography, electrocardiography (ECG), echocardiography, Holter monitoring, exercise test and head-up tilt test were performed. RESULTS: The MVP group consisted of 19 boys and 18 girls with a mean age of 11.8 years. The control group was similar with respect to age and gender. Telecardiography, ECG, Holter monitoring, exercise test and QTc of all children were within normal limits.There was a statistically significant difference between the two groups in terms of QT dispersion. The tilt table test was positive in 11 of 37 (29.7%) children with MVP and in 1 of 26 (3.8%) normal healthy children. This difference was statistically significant (P < 0.01). CONCLUSION: Arrhythmia and syncope frequency was found to be higher in children with MVP than in the normal population. The risk of vasovagal syncope indicated by a positive tilt test was found to be increased in children with MVP. Therefore, patients and families must be informed about the conditions that may predispose to vasovagal syncope and caution should be recommended in these patients.  相似文献   
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Anomalous right coronary artery is a rare entity with an incidence of 0.26%. The anomalous origin usually arises from the left sinus valsalva. An anomalous right coronary artery arising from the left anterior descending artery is rare. It is usually known as a benign entity but may have clinical importance due to its course between the aorta and pulmonary artery which may cause myocardial ischemia or sudden cardiac death. Here we present an anomalous coronary artery arising from the left anterior descending artery detected by coronary artery angiogram and confirmed by multislice computed tomography thereafter. 40% retrospective electrocardiographic gating is performed and volume-rendered 3 D and axial MIP (maximum intensity projection) images were reconstructed on a Vitrea post- processing Workstation. The images demonstrated the anomalous origin of the right coronary artery arising from the proximal portion of left anterior descending artery after the first septal perforator and coursing.  相似文献   
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