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1.
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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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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Zoster paresis     
Herpes zoster (HZ) is essentially a viral disease of the posterior root ganglia and sensory nerve fibers, which presents clinically with vesicular eruption of the skin, radicular pain and sensory changes in the distribution of the affected ganglion. However, motor involvement can be seen as well. If classic cutaneous lesions are present, HZ-related motor paresis is easily diagnosed. Otherwise, the diagnosis may be suspicious, especially if the weakness occurs before the cutaneous lesions have appeared, or weeks after they have subsided. We present a patient with HZ-related motor paresis due to radiculopathy in the cervical segments whose motor symptoms and signs appear as major clinical features.  相似文献   
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In the study, the ameliorating effects of alfa lipoic acid (ALA) against doxorubicin-induced testicular apoptosis, oxidative stress and disrupted mitochondrial fusion were investigated in male rats. Rats were divided into four groups as control, doxorubicin (DOX), DOX + ALA and ALA. A single dose of 15 mg/kg DOX was administered i.p to the DOX and DOX + ALA groups. 50 mg/kg ALA was given to the DOX + ALA and ALA groups by oral gavage every other day. After 28 days, rat testes and serum samples were collected and analysed. Administration of DOX alone caused a decrease in body and relative testicular weights, seminiferous tubule diameter and germinal epithelium thickness, Johnsen's score and serum testosterone levels. DOX treatment led to severe testicular damage such as tubular degeneration, and atrophic tubules. Also, the activities of superoxide dismutase and glutathione peroxidase were reduced, while the level of malondialdehyde was increased in the testis. The mRNA levels of apoptotic-related genes (CASP3, TP53, BAX, BCL2) and apoptotic index were increased, while mitofusin-2 decreased. DOX caused an increase in CASP3 and a decrease in mitofusin-2 immunoreactivities. Treatment with ALA markedly improved all of DOX-induced biochemical, histochemical and molecular alterations in rat testis. Consequently, ALA has a therapeutic role in ameliorating DOX-induced testicular damage in rats.  相似文献   
7.
The constant release of nitric oxide (NO) is essential to maintain basal cerebrovascular tone. Oxyhaemoglobin, liberated by lysis of red blood cells after subarachnoid haemorrhage binds NO and prevents its entry into vascular smooth muscle cells. While endothelium-dependent vasoconstriction is preserved, decreased levels of NO inhibit endothelium-dependent relaxation and may cause vasospasm. S-nitrosothiols are potent vasodilators and precursors of NO. The authors' aim was to determine whether S-nitroso-N-acetylpenicillamine (SNAP), a stable S-nitrosothiol compound, could reverse vasospasm in an experimental vasospasm model in rabbit. Experimental subarachnoid haemorrhage (SAH) was induced in 37 New Zealand white rabbits. The animals were divided into four groups. Control (no SAH), SAH only, SAH plus saline and SAH plus SNAP. SNAP (15 micrograms/kg/min) or 0.09% saline (equal volume) was infused 46 hours after induction of SAH. All animals were killed by perfusion fixation 48 hours after SAH occurred. Basilar arteries were removed, sectioned and their cross sectional areas were evaluated in a blind manner, by light microscopy and by using computer assisted morphometry. Experimental SAH elicited vasospasm in all animals of SAH only and SAH plus saline group. In animals treated with SNAP, arterial narrowing was markedly attenuated without producing systemic hypotension. This widening achieved statistical significance when compared to the arteries of the SAH only and SAH plus saline group (p < 0.01). This study indicates that the NO donor SNAP is a potentially useful drug to reverse cerebral vasospasm due to SAH.  相似文献   
8.
Our objective was to compare the relationship between age, basal follicle stimulating hormone (FSH) level and ultrasound-measured mean ovarian volume (MOV) and mean antral follicle counts (MFC) in a group of infertile and fertile women between the ages of 35 and 45 years. Menstrual cycle day 3 serum FSH, MOV and MFC were analyzed in 62 infertile and 53 fertile women. Basal FSH and MFC did not differ between infertile and fertile women, whereas MOV was significantly smaller in infertile women (p < 0.05). In the infertile group, there was a negative correlation between MOV and age (rho = -0.389, p < 0.05), between MOV and basal FSH (rho = 0.495, p < 0.01), and between MFC and age (rho = -0.553, p < 0.01). In the fertile group, there was a strong negative correlation between MOV and basal FSH (rho = -0.631, p < 0.01), and between MFC and basal FSH (rho = -0.710, p < 0.01). Mean basal FSH, MOV and MFC did not differ between subgroups of patients with different causes of infertility. In the infertile group, patients with small ovaries of volume less than 1.8 cm(3) (mean volume -1 SD) had higher mean basal FSH (p < 0.05) and lower MFC (p < 0.01) levels than patients with normal ovarian volume. In conclusion, transvaginal ultrasound (TVU) indices and indirect hormonal parameters of ovarian reserve were similar in infertile and fertile women aged between 35 and 45 years. It is suggested that, in infertile women above 35 years of age, TVU rather than hormonal parameters be preferred, based on our data showing a stronger association between age and TVU indices of ovarian reserve than between age and increase in basal FSH level. Thus, TVU assessment of ovarian volume and antral follicle counts is a practical and cost-effective, if not better, technique for ovarian reserve testing.  相似文献   
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