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71.
Recent studies suggest that 3-hydroxy-3 methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, statins, can have direct effects on blood vessels beyond their cholesterol-lowering effects. We investigated the effects of atorvastatin on the functional and structural properties of blood-brain barrier (BBB) and the activity of astrocytes during the N(omega)-nitro-L-arginine methyl ester (L-NAME) hypertension followed by angiotensin (ANG) II. We found that decreases in concentration of serum catalase and plasma nitric oxide (NO) induced by L-NAME were significantly ameliorated by atorvastatin, whereas L-NAME-induced serum malondialdehyde and cholesterol concentration increases were significantly reduced by atorvastatin. The content of Evans blue (EB) dye significantly increased in cerebellum, left cerebral cortex and diencephalon regions but atorvastatin markedly reduced the increased BBB permeability to EB in the brain regions of animals treated with L-NAME and L-NAME plus ANG II. Brain vessels of L-NAME-treated animals showed a considerable loss of immunoreactivity of tight junction proteins, zonula occludens (ZO)-1 and occludin. Immunoreactivity for ZO-1 and occludin increased in animals treated with atorvastatin and L-NAME plus atorvastatin. Glial fibrillary acidic protein (GFAP) immunoreactivity was seen in few astrocytes in the brain sections of L-NAME, but immunoreactivity for GFAP increased in L-NAME plus atorvastatin-treated animals. We suggest that long-term L-NAME treatment may affect BBB permeability through disruption of tight junction proteins, at least partly, via decreased NO concentration and increased oxidant capacity; the improvement of BBB integrity and astrocytic activity would be more closely associated with the action of atorvastatin favoring the increase in anti-oxidant capacity and expression of tight junction proteins and GFAP.  相似文献   
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73.
OBJECTIVE: Our aim was to determine whether inward or outward movement of the secretions in the paranasal sinuses due to nose blowing after nasal decongestion has any effect on the paranasal sinus computed tomography (CT) images in patients with sinusitis and to asses whether nose blowing may result in misdiagnosis or overdiagnosis in radiological evaluation of sinusitis. MATERIALS AND METHODS: Twenty-four patients with chronic sinusitis were evaluated in an academic tertiary care hospital and data were collected prospectively. After coronal sinus computed tomography scans were performed at 100 mA setting which was half the value of the standard radiation dose suggested by the manufacturer, topical decongestion was applied to each nostril followed by nose blowing 10 min later. Sinus CT scans were then repeated at the same setting. We evaluated the mucosal thickness of medial, lateral, superior and inferior maxillary and frontal sinus walls and the maximal thickness in anterior ethmoidal cells. The measurements prior to and following nose blowing were compared with Wilcoxon signed ranks test. The obtained images were also staged using Lund-McKay staging system separately and the scores were compared with Student's t-test. RESULTS: We observed a tendency towards reduction in mucosal thickness after nose blowing. There were statistically significant differences between maxillary sinus inferior wall and frontal sinus inferior wall mucosal thickness values prior to and after nose blowing. The difference however was very small, about 0.5 mm in magnitude and Lund-McKay score did not change in any of the patients after nose blowing. CONCLUSION: Nose blowing and topical nasal decongestion does not have any effect on the diagnostic accuracy of sinus CT in chronic sinusitis patients.  相似文献   
74.
In this article, a Wohlfahrtia magnifica otomyiasis case, a 31-year-old, non-mentally retarded patient who had undergone radical mastoidectomy previously is presented. Maggots in the radical mastoidectomy cavity were removed then topical treatment was applied. The maggots were identified as W. magnifica. In cases of myiasis, identification of larvae following direct extraction and application of preventative methods is essential.  相似文献   
75.
Sixty-eight patients who presented with glottic and glottosupraglottic squamous cell carcinoma and who were managed in this department with supracricoid partial laryngectomy (SCPL) with either cricohyoidoepiglottopexy (CHEP) or cricohyoidopexy (CHP), were retrospectively reviewed. The authors analysed the functional and oncological results of the patients. The median follow-up period was 62 months. The average times until decannulation and nasogastric feeding tube removal were 27.7 and 26.4 days, respectively. All patients were successfully decannulated. All patients were able to swallow, but one patient was unable to swallow and had recurrent aspiration. Better functional results were achieved in patients managed with CHEP procedure than the patients managed with CHP procedure. The five-year absolute and cause-specific actuarial survival rates (Kaplan-Meier method) were 78.6 per cent and 93.9 per cent, respectively. The five-year actuarial local control and nodal control rates were 89.5 per cent and 90.4 per cent, respectively. Local recurrence was statistically more likely in patients with positive resection margins (p <0.006). Overall, local control and laryngeal preservation were achieved in 95.6 per cent and 89.7 per cent, respectively. Supracricoid partial laryngectomy procedures (CHEP and CHP) are possible alternatives to total laryngectomy in the treatment of selected advanced glottic and glottosupraglottic carcinomas.  相似文献   
76.
OBJECTIVE: The purpose of this study was to determine plasma malondialdehyde (MDA), superoxide dismutase (SOD), soluble E-selectin (sE-selectin), fibronectin, endothelin-1 (ET-1) and nitric oxide (NO) levels in women with preeclampsia and to find out the relations of diastolic blood pressure with these variables. STUDY DESIGN: We performed a case-control study consisting of randomly selected 34 healthy pregnant women and 35 patients diagnosed as preeclampsia. Lipoperoxidation was ascertained by the formation of MDA. SOD activity was determined by the method of Sun et al. Plasma concentration of NO was estimated using colorimetric assay. Plasma ET-1 and sE-selectin were measured by enzyme-linked immunosorbent assay (ELISA). A nephelometric method for fibronectin quantitation was used. RESULTS: The mean plasma level of MDA was significantly higher and SOD was significantly lower in preeclamptic pregnancies (P<0.001). Plasma concentrations of fibronectin, sE-selectin and ET-1 were significantly increased, whereas NO was significantly decreased in women with preeclampsia than normotensive women (P<0.001). CONCLUSION: Increased plasma levels of MDA, fibronectin, sE-selectin, ET-1, and decreased plasma levels of NO and SOD in preeclamptic patients suggest that poorly perfused fetoplacental unit is the origin of oxygen free radicals and lipid peroxides.  相似文献   
77.
BACKGROUND AND OBJECTIVE: To compare the effects of sevoflurane and desflurane anaesthesia on lipid peroxidation. METHODS: We studied 40 healthy patients undergoing elective laparoscopic cholecystectomy. Patients were randomly allocated to be anaesthetized either with sevoflurane (n = 20) or desflurane (n = 20). Anaesthesia was maintained with inspiratory concentrations of sevoflurane 1-1.5 MAC (n = 20) or desflurane (n = 20). Samples were taken for plasma malondialdehyde and superoxide dismutase assays before induction of anaesthesia, before skin incision and at the end of surgery. Alveolar cell samples were obtained from the lungs using the technique of protective blind bronchoalveolar lavage, after induction of anaesthesia and at the end of surgery for malondialdehyde and superoxide dismutase concentrations. RESULTS: Plasma malondialdehyde increased more after the administration of desflurane than after sevoflurane: after induction 5.9 +/- 0.6 nmol mL(-1) for desflurane vs. 3.8 +/- 0.5 nmol L(-1) for sevoflurane (P < 0.001); at the end of the surgery: 6.7 +/- 0.4 nmol mL(-1) for desflurane vs. 4.2 +/- 0.3 nmol mL(-1) for sevoflurane (P < 0.001). There was a small but significant increase in plasma superoxide dismutase concentration after desflurane--from 24.2 +/- 1.2 to 24.9 +/- 0.9 U mL(-1) after induction and 25 +/- 1 U mL(-1) at the end of the surgery (P < 0.01)--but no increase with sevoflurane. Malondialdehyde concentrations increased significantly in the cells obtained by protective blind bronchoalveolar lavage at the end of surgery in the desflurane group (from 0.3 +/- 0.1 to 1.7 +/- 0.2 nmol mL(-1) (P < 0.001)), but not in the sevoflurane group. There were no significant differences between the two anaesthetics in the amounts of superoxide dismutase in the samples obtained by protective blind bronchoalveolar lavage. CONCLUSIONS: Desflurane may cause more systemic and regional lipid peroxidation than sevoflurane during laparoscopic cholecystectomy in healthy human beings.  相似文献   
78.
OBJECTIVES: It is well documented that children, particularly between the ages of about 2 and 6 years, exhibit a high prevalence and incidence of otitis media. Distortion product otoacoustic emissions (DPOAEs) offer great potential for clinical testing of cochlear function in children. The aim of the present study was to determine the influence of middle ear effusion and physical properties of the effusion on the recording of DPOAE. METHODS: Nineteen children (38 ears) undergoing myringotomy and/or tympanostomy tube insertion for secretory otitis media were studied. Pre-operative and post-operative first day DPOAE signal to noise ratios were compared. The results were analyzed by paired samples test and ANOVA statistical methods. RESULTS: We were found significant differences between pre-operative and post-operative first day DPOAE signal to noise at 1, 1.5, 2 and 4kHz. In addition, comparison of the pre-operative DPOAE signal to noise ratio and per-operative middle ear findings are shown significant differences between glue (thick mucous) and the other three groups (mucous, serous and no-effusion groups) at 2 and 4kHz, and between glue and no effusion group at 8kHz. Also post-operative DPOAE signal to noise ratio in relation to per-operative middle ear findings were significantly different at 2, 4 and 8kHz. The most increase of emissions at the post-operative first day was seen in ears with glue effusion at 1 and 2kHz. CONCLUSIONS: Otitis media with effusion can be monitored by DPOAE measurement pre-operatively and post-operatively. In the pre-operative evaluation, glue effusion may cause a reduction in the emissions at 2, 4 and 8kHz more than the other kind effusions.  相似文献   
79.
OBJECTIVE: To evaluate by computed tomographic scanning the paranasal mucosal changes of coal workers with and without pneumoconiosis. METHODS: Examination of images and scores from paranasal computed tomographic scans. The study participants were 26 coal workers with pneumoconiosis, 29 coal workers without pneumoconiosis, and 20 controls. All were men. The extent and patterns of inflammatory paranasal sinus disease were evaluated on computed tomographic scans by 2 radiologists using the terminology and definitions of Newman and associates. RESULTS: Interobserver agreement for the presence of abnormalities was from good to excellent (kappa, 0.63-0.89). The mucosal scores of individuals and groups were higher for coal workers than for control subjects. Both scores were significantly higher in the pneumoconiosis group than in the 2 other groups. CONCLUSIONS: This study shows that paranasal sinuses were affected more severely in coal workers than in control subjects. In coal workers with pneumoconiosis, the affection was most severe. The relationship between coal dust exposure and paranasal mucosal changes needs further study.  相似文献   
80.
We aimed to investigate whether there is a direct correlation of serum IgE concentration with severity of acute pulmonary thromboembolism (PTE). DESIGN: Prospective study. SETTINGS: University medical center. Forty-six patients (27 female, 19 male) who were diagnosed as acute PTE in our clinic between 01 October 2000 and 30 November 2001 comprised the study group. Mean age was 55 (range was 20-82). The study group was divided into three groups according to severity of PTE: Group A, submassive PTE without pulmonary infarction (20 patients); group B, submassive PTE with pulmonary infarction (15 patients); and group C, massive PTE (11 patients). Serum IgE concentrations were measured by ELISA method at 1st, 5th, 15th, 30th, 60th, 90th days, and 120th days, if needed, after the diagnosis. Statistical analysis was made by Post hoc Tukey test. First day serum IgE levels were highest in group B (mean 507.7) followed by group C (mean 324.2), and were lowest in group A (mean 117.2). The differences between group B and group C, between group B and group A, and also between group C and A were all statistically significant (p< 0.5, p< 0.0001, p< 0.015, respectively). 5th day and 15th day results showed statistically significant differences between group B and A, and between group C and A (at 5th day: p<0.0001, p< 0.015 respectively, and at 15th day: p< 0.0001, p< 0.012 respectively). At 30th, 60th, and 90th days of diagnosis serum IgE concentrations were higher in group B than in group A which were statistically significant (p< 0.0001, p< 0.0001, p< 0.019 respectively). Patients with submassive PTE and pulmonary infarction had the highest serum IgE concentrations and the longest duration of high levels of IgE.  相似文献   
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