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The aim of this study was to investigate the role of nitric oxide (NO), free oxygen radicals, and scavenging enzymes in the development of nasal polyp (NP) disease. This study included 41 patients who underwent endoscopic surgery because of NPs. Control specimens were taken from the inferior turbinate of 32 patients who underwent septoplasty. The levels of malondialdehyde (MDA), NO, and superoxide dismutase (SOD) were measured in intraoperative specimens of polyp tissue and turbinate mucosa. The levels of tissue NO were 191.06 +/- 26.62 micromol/mg of protein in patients with NPs and 145.30 +/- 19.19 micromol/mg of protein (p < .001) in the control group. The levels of MDA in the study and control groups were 12.47 +/- 2.12 nmol/mg and 8.83 +/- 1.08 nmol/mg (p < .01), respectively. The levels of SOD in the study and control groups were 50.77 +/- 14.74 U/mg and 77.93 +/- 15.31 U/mg (p < .001), respectively. It was determined that the levels of MDA in plasma and erythrocytes were higher in the patients with NPs than in the control group (p < .05). The levels of NO in plasma and erythrocytes in both groups were similar. The levels of SOD in plasma and erythrocytes were lower in patients with NPs than in the control group (p > .05). Increases in the levels of tissue MDA and NO and decreases in scavenging enzymes in patients with NPs as compared to control groups may indicate the presence of free radical damage in patients with nasal NPs. New studies are needed to clarify the efficacy of using antioxidants in the treatment of NPs.  相似文献   
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OBJECTIVE: To evaluate the correlation between adenoidal-nasopharyngeal ratio (AN ratio) and tympanogram in children. STUDY DESIGN: A prospective clinical study from June 2002 to May 2003. METHOD: A total of 64 children, aged 6-9 years who presented with nasal obstruction, snoring, mouth breathing, and hyponasal speech were examined and AN ratio was calculated by using the lateral neck radiograms and compared with the tympanometric values. The relationship between AN ratio and middle-ear pressure was evaluated, regarding the AN ratio of 0.71. The chi-square test was used to analyze the correlation between AN ratio and middle ear pressures and Wilcoxon test was used to compare the changes between the mean AN ratio values, and mean middle ear pressures (including A and C type tympanograms) before and after medical therapy. RESULTS: Middle-ear effusions and C type tympanograms in impedance audiometry were both related to eustachian tube dysfunction resulting from enlargement of the adenoids with AN ratios higher than 0.71. Middle ear pressures were found lower in children with AN ratio greater than 0.71 than in children AN ratio less than 0.71 and the difference was highly significant (p<0.001). Although medical treatment of large adenoids was rather effective to shrink the adenoid tissue (p<0.001), it did not cause a statistically significant change in tympanometric values (p>0.05). CONCLUSIONS: Antibiotherapy is effective in reducing adenoid size without signs and symptoms of infection. The reduction of the adenoids in size after 3 weeks of antibiotherapy has an positive effect on recovery of eustachian tube function but is not sufficient in patients with middle ear effusion. Early ventilation tube insertion may be an alternative therapy for the middle ear effusions not improving by 3 weeks medical therapy.  相似文献   
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Background Although attitudes towards psychiatric illness influence its presentation, detection, recognition, treatment adherence and rehabilitation, the lay public's opinions and beliefs about the treatment of depression have not been investigated sufficiently. Objective The aim of this study was to determine public opinions and beliefs about the treatment of depression and the influence of perception and causal attributions on attitudes towards treatment of depression in urban areas. Methods This study was carried out with a representative sample in Istanbul, which is the biggest metropolis in Turkey. Seven hundred and seven subjects completed the public survey form which consisted of 32 items rating attitudes towards depression. Results The public believes that psychological and social interventions are more effective than pharmacotherapy, and that the medicines used in treatment of depression are harmful and addictive. There was a general reluctance to consult a physician for depression, and psychiatrists were felt to be more helpful than general practitioners. The public viewed depression as treatable. A high educational level and perceiving depression as a disease is associated with positive beliefs and opinions about the treatment of depression; but the perception of depressive patients as aggressive is associated with negative beliefs and opinions about the treatment of depression. Conclusion The beliefs that “psychological and social interventions are more effective than pharmacotherapy” and “antidepressants are harmful and addictive” must specifically be taken into account in clinical practice and in anti-stigma campaigns. Additional studies are needed to understand the public's tendency to conceptualise depression as a psychosocial problem. In clinical practice, depression should be introduced as a bio-psychosocial disease whatever its cause: biological, psychological or social. In addition, the differences between extreme worry and disease, and the lack of aggressiveness of depressive patients, must be emphasised.  相似文献   
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The authors investigated the effects of ischemia and reperfusion on the N-methyl-D-aspartate receptor (NMDAR) subunits 2A and 2B concentration in rat hippocampus. At the protein level, significant increase in the amounts of NMDAR 2A and NMIDAR 2B in the rat hippocampus was observed at 1 h after reperfusion compared with control group. These results suggested that the alteration in hippocampal NMDAR2 subunit concentrations after ischemia-reperfusion might be invovlved in cognitive dysfunction and excitotoxicity.  相似文献   
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