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BACKGROUND: Despite plenty of research, the cause of recurrent aphthous stomatitis (RAS) remains obscure. It has been proposed that, the aetiological factors such as local trauma, smoking, vitamin deficiencies and viral infections lead to aphthae formation via final common pathway based on increased oxidative stress. The aim of this investigation was to evaluate the antioxidant enzyme superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) alterations in plasma and saliva, and in addition uric acid (UA) in saliva, in patients with RAS and healthy controls. METHODS: Thirty-two patients with RAS and 30 healthy controls were included into the study. The SOD, CAT, GSHPx and UA levels were measured in plasma and saliva in study and control groups. RESULTS: In the RAS group, although the mean SOD (P<0.001) and CAT (P<0.05) levels of plasma were lower, GSHPx (P<0.001) levels were higher than control group. The salivary concentrations of the SOD (P<0.001), CAT (P<0.05) and GSHPx (P<0.001) in RAS group were entirely opposite to plasma concentrations. UA were not significant between RAS group and controls. CONCLUSION: Since we found salivary SOD and CAT levels were high whereas plasma levels were low, it has been thought that, salivary defence mechanisms via antioxidant agents may be stimulated against to the ulcerous lesion. We consider that the organism might mobilize the antioxidant potential to the sites where they were needed. At this point, decrease of SOD and CAT levels in the plasma may be related to this shift. It is also thought that GSHPx secretion in the saliva may also be increased but the increase in its turnover may be responsible for the diminished activity.  相似文献   
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The exposure to Aspergillus organisms/spores is likely common, but disease caused by tissue invasion with these fungi is uncommon and occurs primarily in the setting of immunosuppression. We report a case of rapidly advancing invasive endomyocardial aspergillosis secondary to prolonged usage of multiple broad-spectrum antibiotics in a nonimmunocompromised host. A 36-year-old cotton textile worker presented to our institution with a 3-month history of weight loss and fatigue. He reported receiving prolonged use of multiple broad-spectrum antibiotic treatment. The echocardiogram demonstrated multiple endomyocardial vegetations and a mass in the left atrium. Myocardial biopsy specimen revealed an invasive endomyocardial aspergillosis. The patient was investigated for immune deficiency including HIV, and this workup was negative. Treatment was started with amphotericin B and heparin for presumed left atrial thrombus. The patient died because of a rupture of mycotic aneurysm that resulted in cerebral hemorrhage. This case illustrates the risk of an invasive fungal infection in a nonimmunocompromised host who is a prolonged user of antibiotics in the setting of environmental exposure of opportunistic invasive fungal infections.  相似文献   
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A 24-year-old man presented with a 24-hour history of pain and numbness in his left arm. The patient's clinical presentation of peripheral embolism was corroborated by angiography. Echocardiographic study showed masses in both right and left atria. Pathologic specimen from the embolus confirmed the diagnosis of aspergillosis.  相似文献   
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Renal vasoconstriction and ischaemia that follow in vitro antigen challenge of isolated perfused kidney of sensitized guinea-pig appears to be a self-perpetuating process, starting with a primary peak of release of vasoconstrictor mediators and followed by secondary peaks (particularly of arachidonic acid metabolites) which are probably initiated by ischaemia/reperfusion damage.  相似文献   
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PURPOSE: Bone healing is impaired in diabetes mellitus, particularly due to increased collagen breakdown. Recently, tetracyclines have been used to treat experimental bone defects because they have anticollagenolytic properties, and positive effects on the healing process have been obtained. The objective of this study was to develop a computer-assisted histomorphometric technique to quantitatively determine the amount of regenerating bone within experimental bone defects in a diabetic rodent model. MATERIALS AND METHODS: This study examined the effects of systemic doxycycline administration on the healing of tibial bone defects in healthy albino rats and in experimentally induced diabetic rats. Twenty-four female albino rats were assigned to 4 groups: diabetic, diabetic plus doxycycline, control, or control plus doxycycline. The standardized bone defects were histomorphometrically examined 10 and 30 days postoperatively. Histomorphometric analysis of the amount of new bone formation was performed using the Zeiss Vision image analysis program KS 400 (Kontron Elektron GmbH, Eching, Germany). RESULTS: At 10 days of healing, the diabetic groups exhibited inferior healing compared with the control groups in terms of the amount of new bone formation within the defects. However, the effect of doxycycline administration to the diabetic and control groups was not statistically different. At 30 days of healing, there were no statistically significant differences between the amount of newly formed bone in any of the groups. CONCLUSIONS: This study found that doxycycline administration did not significantly alter the amount of new bone formation during the healing of bone defects in control and diabetic rats.  相似文献   
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We present the case of a patient with juvenile onset systemic lupus erythematosus (SLE) who developed a persistent, acquired hypogammaglobulinaemia with IgG deficiency. The hypogammaglobulinaemia was probably a complication of high dose corticosteroid treatment. The serum IgG level remained subnormal despite intravenous immunoglobulin therapy. Lupus vulgaris, which developed on the nasal cartilage in this patient with SLE, is not an expected finding. This patient is probably the first reported case of SLE associated with lupus vulgaris.  相似文献   
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