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Ligneous periodontitis (LP) is a rare periodontal disease in which plasminogen deficiency and fibrin deposition both play a part, resulting in characteristic gingival enlargement and periodontal breakdown. Recent data suggest that oxidant/antioxidant changes are significant in the pathology of oral diseases. This study examines the gingival histopathology in 2 cases with LP. To examine the antioxidant (AO) status, the activity of the major AOs glutathione (GSH), catalase (CAT), and glutathione S-transferase (GST) and the malondialdehyde (MDA) levels, a product of lipid peroxidation, were measured and compared with healthy control subjects. The histopathologic examination of the gingiva revealed subepithelial fibrin accumulation and irregular extensive downward proliferation of the epithelium. Biochemical analysis showed that the CAT, GST, and MDA levels were higher in LP patients than in the control subjects, and the GSH level was lower. Our preliminary findings show that in LP, the AO capacity of the gingiva changes or decreases and lipid peroxidation increases, which suggests that oxidative stress is involved in the pathology of the periodontal breakdown observed in this disease.  相似文献   
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The presence of certain defects in both cellular and humoral immunity after thermal injury has been established. Likewise, the translocation of enteric bacteria to the mesenteric lymph nodes and to distant organs has also been observed following serious thermal injury. The effects of granulocyte colony-stimulating factor (G-CSF) on bacterial translocation, the small bowel mucosa, and cecal bacterial content were investigated in a rat model of burn wound sepsis in which albino Wistar rats were scalded over 30% of their bodies, after which the lesions were infected by 1×108 colony-forming units (cfu)Pseudomonas aeruginosa. The control group was treated with 5% dextrose solution subcutaneously starting 2 days preburn, while the treatment group received 100μg/kg human G-CSF subcutaneously. On the 4th day post burn all animals were killed to examine the bowel and culture of the mesenteric lymph nodes (MLN), livers, and spleens. No significant differences were observed between the groups regarding the cecal bacterial content and small bowel; however, a difference was seen in the ratio of translocation in the MLN liver and spleen and quantitative MLN cultures. Based on these findings, G-CSF was thus found to be significantly effective in reducing bacterial translocation due to burn wound sepsis.  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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Senna occidentalis (So) is a weed that grows in pastures along fences and in fields cultivated with cereals such as corn and soybean, and many reports have been showing intoxication with this plant in different animal species. It is also used in many medicinal purposes. The objective of the present study was to better evaluate the toxic effects of prolonged administration of So seeds to rats. Forty male Wistar rats were divided into four groups of 10 animals each, three of them respectively fed rations containing 1%, 2% and 4% So seeds, and the last one (control) fed commercial ration for a period of 2 weeks. Fourteen rats were also used in a pair-feeding (PF) experiment. The rats of the experimental groups showed lethargy, weakness, recumbency, depression and emaciation. Two rats of the 4% group and two of the PF group died during the experiment. Histopathological study showed fiber degenerations in the skeletal (Tibial, pectoral and diaphragm) and cardiac muscles. In the liver parenchyma, was observed vacuolar degeneration and, in the kidney, mild nefrosis in the proximal convoluted tubules. All of these alterations occurred in a dose-dependent fashion. Moderate to severe degeneration and spongiosis in the central nervous system, especially in cerebellum. Electron microscopy revealed mitochondrial lesions in all analyzed tissues.  相似文献   
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BACKGROUND: Cyclooxygenase-2 (COX-2) inhibitors are reported to be well tolerated in patients with analgesic intolerance (AI). However, limited data are available about the long-term tolerability of these drugs. OBJECTIVE: To determine the long-term tolerability of COX-2 inhibitors in patients with Al. METHODS: Patients with AI who previously underwent single-masked, placebo-controlled oral provocation tests and were found to tolerate nimesulide, meloxicam, rofecoxib, or celecoxib were interviewed regarding the long-term use and tolerability of these drugs. RESULTS: Of 87 patients, 61 (70%) had used the recommended COX-2 inhibitor(s). Of the 61 users, 54 (89%) tolerated the drug(s) well and 7 (11%) reported adverse events. Three patients reporting adverse events were rechallenged with the responsible COX-2 inhibitor, and their results were found to be negative. CONCLUSIONS: Long-term use of COX-2 inhibitors was tolerated well by most patients with AI, and placebo-controlled oral provocation tests, as a single test, seemed to predict tolerability. Furthermore, self-reported positive reactions in the long-term should also be confirmed with rechallenge tests for definite diagnosis.  相似文献   
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A family with cardiac malformation, cleft lip-palate, short stature, microcephaly, distally placed thumbs, short 2nd and 5th fingers, long and broad 1st toes, broad distance between 1st and 2nd toes and mediodorsal curvature of the 4th toes with syndactyly of the 2nd and 3rd toes has been described as having a new syndrome. While some members of the family had full signs of the syndrome, others had similar but fewer and less severe anomalies of the same structures. The presence of common findings in three generations, its variable expressivity and pleiotropism, and the non-consanguineous history in the parents suggest that the inheritance is autosomal dominant.  相似文献   
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The aim of this study is to evaluate the effects of low-level laser therapy (LLLT) on (1) the velocity of orthodontic tooth movement and (2) the nitric oxide levels in gingival crevicular fluid (GCF) during orthodontic treatment. The sample consisted of 20 patients (14 girls, six boys) whose maxillary first premolars were extracted and canines distalized. A gallium-aluminum-arsenide (Ga-Al-As) diode laser was applied on the day 0, and the 3rd, 7th, 14th, 21st, and 28th days when the retraction of the maxillary lateral incisors was initiated. The right maxillary lateral incisors composed the study group (the laser group), whereas the left maxillary lateral incisors served as the control. The teeth in the laser group received a total of ten doses of laser application: five doses from the buccal and five doses from the palatal side (two cervical, one middle, two apical) with an output power of 20 mW and a dose of 0.71 J /cm2. Gingival crevicular fluid samples were obtained on the above-mentioned days, and the nitric oxide levels were analyzed. Bonferroni and repeated measures variant analysis tests were used for statistical analysis with the significance level set at p ≤ 0.05. The application of low-level laser therapy accelerated orthodontic tooth movement significantly; there were no statistically significant changes in the nitric oxide levels of the gingival crevicular fluid during orthodontic treatment.  相似文献   
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