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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 serotonin 2 (5-HT(2)) receptor antagonists, MCI-9042 (Anplag) and ketanserin, have been shown to lower intraocular pressure in rabbits (1) and humans (2). The mechanism of action of these drugs has not been determined, but it is hypothesized that 5-HT(2) receptors, and possibly alpha-adrenergic receptors, (3) may regulate in part aqueous humor production via an intracellular signal transduction pathway in the ciliary body. We therefore examined whether 5-HT(2) receptors were coupled to phosphoinositide hydrolysis in an organ culture system of isolated bovine ciliary epithelium. 5-HT stimulated [(3)H]inositol phosphates ([(3)H]InsPs) accumulation in a dose-dependent manner with a maximum increase approximately twice over the basal level. The mean EC(50) value was 1.1 microM, which was calculated from four dose-response curves. The 5-HT stimulated accumulation of [(3)H]InsPs was inhibited by spiperone (5-HT(2A/1A) and dopamine 2 (D(2)) antagonists), M-1 (a major metabolite of MCI-9042), ketanserin (5-HT(2A) antagonist), SB-206553 (5- HT(2B/2C) antagonist), and mesulergine (5-HT(2C) antagonist and D(2) agonist). It was not inhibited by chlorpromazine, which is a D(2) receptor antagonist. Accordingly, our study demonstrates that 5-HT(2) receptors are coupled to phospholipase C in bovine ciliary epithelium.  相似文献   
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Uptake of dehydroascorbic acid (DHA) was studied in two types of dog erythrocytes with high GSH and normal GSH levels. Compared with ascorbic acid uptake, DHA produced a much greater ascorbic acid accumulation in dog erythrocytes. Both dog erythrocytes showed a concentration dependence of DHA uptake, and cellular ascorbic acid concentrations were significantly higher in high-GSH cells than in normal-GSH cells. Glucose and cytochalasin B inhibited DHA uptake. This suggests that DHA enters dog erythrocytes predominantly by the facilitated glucose transporter, particularly by the Glut 1 glucose transporter. The rate of glucose uptake was quite similar in the two types of cells. Compared with normal-GSH cells, high-GSH cells were more resistant to oxidative stress induced by high concentration of DHA. As a rapid entry of DHA inflicts on cells a heavy demand for GSH for its reduction to ascorbic acid, high-GSH cells containing a larger reserve of GSH have an advantage over normal-GSH cells in both ascorbic acid accumulation and resisting oxidative stress produced by DHA.  相似文献   
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Alexia with agraphia is very rare symptom in multiple sclerosis. We present a patient of opticospinal multiple sclerosis with kanji-predominant alexia with agraphia. A 55-year-old, right-handed man was admitted to our hospital because of difficulty in reading and writing in August 2001. The patient had been diagnosed as having relapsing-remitting opticospinal multiple sclerosis eight years prior to admission. Language examination showed alexia with agraphia predominantly affecting kanji and also mild naming difficulties, but a good comprehension and a normal repetition. T2-weighted MRI demonstrated hyperintensity area in the left temporo-parietal lobe, involving the white matter beneath the postero-inferior temporal lobe and inferior parietal lobule. On brain SPECT, low blood perfusion was observed in the left temporo-parietal regions. Although agraphia for kana and alexia for both kana and kanji improved after steroid therapy, agraphia for kanji did not improve. After the treatment, high intensity area of inferior parietal lobule was disappeared on MRI, and the hypoperfusion of inferior parietal lobule on brain SPECT was also improved, but the lesion of left postero-inferior temporal lobe did not show any remarkable changes. We considered that the kanji-predominant alexia with agraphia was due to the lesions of left inferior parietal lobule and postero-inferior temporal lobe, and agraphia for kanji was due to the lesion of left postero-inferior temporal lobe.  相似文献   
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Lidocaine with epinephrine is currently the most common local anesthetic agent used for impacted third molar surgery. The purpose of the present study was to define the adverse hemodynamic effects and plasma concentrations of lidocaine and epinephrine on 17 healthy patients during the impacted teeth operations. Arterial blood pressure (systolic blood pressure, diastolic blood pressure), heart rate, peripheral oxygen saturation range, and electrocardiography were measured by an automatic noninvasive pressure device and monitor. High-performance liquid chromatography was used to measure the changes of plasma concentrations of epinephrine and lidocaine from blood samples taken 5 different times during the operation. We concluded that lidocaine-epinephrine is effective local anesthetic and had no important adverse events in healthy patients during the third molar surgery.  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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To investigate the usefulness of the frontal assessment battery (FAB) as a brief assessment for diagnosis in patients with dementia, we examined cognitive function using the FAB, Mini-mental state examination (MMSE), Kana-hiroi test, and Raven's colored progressive matrices (RCPM). Subjects were 82 senile patients having amnesia as a complaint including 28 Alzheimer's disease (AD), 14 frontotemporal dementia (FTD), 17 vascular dementia (VD), 13 mild cognitive impairment (MCI), and 10 healthy persons. We discussed the difference of scores in different types of dementia. In the FAB, the scores of healthy persons and MCI were much higher compared with the scores of all types of dementia. There were high correlation between FAB and MMSE, Kana-hiroi test, and RCPM. Although some subjects showed normal score in MMSE and/or RCPM, they showed low score in FAB. Based on this, FAB is efficient for the differential diagnosis of dementia as brief screening tool.  相似文献   
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