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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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Benign intracranial hypertension (BIH) is reported in three children from Australia and one from New Zealand, who were being treated with recombinant human growth hormone (rhGH). Three males and one female, aged between 10.5 and 14.2 y, developed intracranial hypertension within 2 weeks to 3 months of starting treatment. A national database, OZGROW, has been prospectively collecting data on all 3332 children treated with rhGH in Australia and New Zealand from January 1986 to 1996. The incidence of BIH in children treated with growth hormone (GH) is small, 1.2 per 1000 cases overall, but appears to be greater with biochemical GHD (<10IUml -1), i.e. 6.5/1000 (3 in 465 cases), relative risk 18.4, 95% confidence interval 1.9-176.1, than in all other children on the database. The incidence in patients with Turner's syndrome was 2.3/1000 (1 in 428 cases). No cases in patients with partial GHD (10–20 IUml -1) or chronic renal failure were identified. Possible causative mechanisms are discussed. The authors'practice is now to start GH replacement at less than the usual recommended dose of 14IUm-2 week-1 in those children considered to be at high risk of developing BIH. Ophthalmological evaluation is recommended for children before and during the first few months following commencement of rhGH therapy and is mandatory in the event of peripheral or facial oedema, persistent headaches, vomiting or visual symptoms. The absence of papilledema does not exclude the diagnosis.  相似文献   
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合成了18个O,O′-二烷基-O″-(5-取代-3-苯并噻吩乙腈肟)磷酸酯及硫代磷酸酯类化合物(Ⅰ1~18)。初步杀螺试验结果表明,其中5个化合物,即Ⅰ2,3,7,11,12有明显的杀螺增效作用。  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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AIM: The objective of this study is to analyze the complication rates after the completion thyroidectomy and compare them with primary total thyroidectomy. METHODS: The outcomes of patients with differentiated thyroid carcinoma who were operated over a period of eight years were evaluated. One hundred and forty-one patients underwent completion thyroidectomy and 92 patients had primary surgery. RESULTS: The two groups were comparable in respect of clinical variables. Residual tumor was found in 66 of 141 patients (46.8%) in completion thyroidectomy group. The rate of the two most important complications, permanent recurrent laryngeal nerve palsy and permanent hypoparathyroidism were 3.5 and 4.2%, in completion thyroidectomy group, and 3.3 and 4.3%, in primary total thyroidectomy group. The complication rates were not significantly different between groups. CONCLUSION: In conclusion, completion thyroidectomy can be done safely in a specialized center with acceptable morbidity.  相似文献   
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