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111.
This study examined the chemopreventive effect of Nigella sativa and some of its antioxidant constituents on a number of colon cancer biomarkers in rats induced with azoxymethane (AOM). Sixty male Sprague-Dawley rats were randomly assigned into ten subgroups: vehicle (1-5) and experimental (6-10). The rats in each group were fed one of the following diets: basal diet, (200 mg/kg) Nigella sativa, (0.2 mg/kg) selenium, (1.2 mg/kg) all-trans-retinol plus (100 mg/kg) DL-alpha-tocopherol and (10 mg/kg) thymoquinone, respectively. Only rats in subgroups 6-10 were injected with AOM (15 mg/kg) once per week for 2 weeks. Both groups were fed their respective diets for 5 weeks. Then they were killed and examined for colonic aberrant crypt foci (ACF). Our result showed that only vitamin supplementation was effective on ACF. Nigella sativa revealed inhibitory effects only on DNA damage (day 34) in the AOM-treated rat group. Alternatively, selenium, thymoquinone and vitamins inhibited the MDA content in the liver. Although the exact mechanisms involved in the protective role of Nigella sativa against the initiation of colon carcinogenesis are not clearly understood, the results suggest that its inhibitory effects might depend on the combined competitive inhibition of various antioxidant constituents of this plant.  相似文献   
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A case is reported of the avulsion of the insertion of Extensor Carpi Radialis Longus, an injury that has been reported only once before. The anatomy of the region and mechanism of injury are discussed, as is the importance of open reduction with internal fixation.  相似文献   
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BACKGROUND: The Cox maze procedure is considered an effective surgical treatment of atrial fibrillation in patients with and without organic heart disease. Radiofrequency energy offers an alternative to the complex surgical maze procedure. We used the radiofrequency modified maze III procedure in patients with atrial fibrillation undergoing elective concomitant cardiac surgery. This study evaluated the long-term results of the irrigated radiofrequency ablation to create linear lines of conduction block endocardially. METHODS: Between November 1995 and June 2001, 200 patients with mainly structural heart disease and chronic atrial fibrillation underwent intraoperative radiofrequency linear ablation in both atria with concomitant cardiac surgery. RESULTS: The in-hospital mortality rate was 3.5% (7 patients) and during the mean follow-up of 40 months (range, 12 to 80) 27 patients (13.5%) died. Eight patients (4%) were lost from follow-up and complete data were available in 158 survivors. Sinus or atrial rhythm was present in 116 patients (73.4%) and an atrial driven rhythm in 10 patients (6.3%) with an atrioventricular pacemaker. Atrial fibrillation or flutter was documented in 32 patients (20.3%). Antiarrhythmic drugs were used in 49% of survivors who were free of atrial fibrillation or flutter. CONCLUSIONS: Intraoperative radiofrequency endocardial ablation is an effective technique to eliminate atrial fibrillation with promising long-term results.  相似文献   
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Abstract

In this study, we investigated the therapeutic efficacy of a combination of liposomal amphotericin B (Lip-Amp B) and Methylglyoxal (Lip-MG) against Candida albicans in the leukopoenic mice. The antifungal efficacy of Lip-Amp B or Lip-MG or a combination of Lip-Amp B and Lip-MG was evaluated by the analysis of the survival rate and the fungal load in the treated mice. The immune-stimulatory effect of Lip-MG on macrophages was evaluated by analysing the secretion of proinflammatory cytokines. C. albicans infected mice treated at the doses of 1 and 2?mg/kg of Lip-Amp B showed 20% and 50% survival rates, respectively. Whereas the mice treated with free Amp B at the same doses died within 40?days of treatment. Interestingly, C. albicans infected mice treated with a combination of Lip-Amp B and Lip-MG had 70% survival rate on day 40 postinfection. Moreover, treatment of macrophages with Lip-MG increased their fungicidal activity and the secretion of proinflammatory cytokines, including TNF-α and IL-1β. These findings suggested that co-treatment with Lip-Amp B and Lip-MG had a synergistic effect and could be effective against C. albicans in immunocompromised subjects.  相似文献   
116.
A 3 year-old girl presented with a 6- months history of facial swelling in the region of cheek. Physical examination revealed a firm, non-tender, non- erythematous, mobile, 3 × 3 cm mass in the right cheek. Fine needle aspiration biopsy of the mass demonstrated significiant mitotic activity, slight pleomorfism and atypical cells. A transoral incisional biopsy was also done for accurate diagnosis and the tumor was diagnosed as sialoblastoma. After performing superficial parotidectomy, the tumor was excised with large margins. No adjuvant treatment was given and no recurrence has been noted after 6 months. Despite the rareness of the disease, pathologists and otolaryngologists should always consider the possibility of sialoblastoma of salivary glands in childhood and it can be best described as locally agressive with malignant potential.  相似文献   
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Nasal polyps are benign mucosal protrusions that expand into the nasal cavity. There are no any etiological factors that may explain the pathogenesis of nasal polyps but currently inflammation continues to be the major factor. As a result of inflammation, neutrophils become activated and migrate to the inflammatory area and form their bactericidal effects by producing free oxygen radicals. The objective of our study is to investigate the expression of myeloperoxydase enzyme, which is usually an indicator of leukocyte infiltration and is responsible in the formation of free oxygen radicals in polyp tissues and to determine its role in the pathogenesis of nasal polyps.  相似文献   
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