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1.
There is a large body of literature describing the causative role of oxidative stress mediated by increased levels of reactive oxygen species in the pathogenesis of cardiovascular disease such as atherosclerosis, hypertension, and restenosis after angioplasty. The positioning of a soft silicone collar around the rabbit carotid artery elicits intimal thickening. The findings from recent studies demonstrated that both intimal thickening and atherosclerosis lead to synthesis of inducible nitric oxide synthase, resulting in abundant amounts of nitric oxide. We investigated the effects of collaring and nicardipine treatment on the activities of antioxidant enzymes, superoxide dismutase and catalase, and total nitrite/nitrate levels, stable products of nitric oxide. Placing the collar increased the total nitrite/ nitrate levels and decreased superoxide dismutase activity in collared arteries. Treatment with nicardipine (20 mg/kg/day, s.c.) prevented enhanced nitric oxide degradation without affecting superoxide dismutase and catalase activities. Our results suggest that enhanced nitric oxide production and superoxide anion are generated in response to the collaring, resulting in oxidative stress within the segment in this model.  相似文献   
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Five-day-old Wistar albino rats were injected with kainic acid (KA) or saline i.p. to investigate time-dependent alterations in morphology and number of basic fibroblast growth factor (bFGF) immunoreactive (-ir) astrocytes and neurons in hippocampus at 15, 30, and 90 days after the injections. Sections were stained with cresyl violet for morphological evaluation and bFGF immunohistochemistry was used for quantitative evaluation of bFGF-ir cell density. Fifteen days after KA injection, there was gliosis but no neuronal loss although disorganization in CA1, CA3, CA4 pyramidal layers and neuronal loss were evident 30 and 90 days after the injection. KA injected rats demonstrated significantly increased number of bFGF-ir astrocytes throughout the hippocampus and pyramidal neurons in CA2 after 15 days and decreased number of bFGF-ir cells after 30 and 90 days. The decrease in the number of bFGF-ir astroglia and neurons in long term after KA injection may indicate a decrease in the production of bFGF and/or number of bFGF-ir cells suggesting that protective effects of bFGF may be altered during epileptogenesis in hippocampus.  相似文献   
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OBJECTIVE: The aim of this study was to evaluate the audiovestibular disturbance in patients with systemic lupus erythematosus (SLE). STUDY DESIGN AND SETTING: Twenty-eight patients with SLE and 28 healthy control subjects were included. Pure-tone audiometry, impedance audiometry, and electronystagmography (ENG) were used for baseline evaluation. Laboratory tests were carried out. Cranial and brain stem magnetic resonance imagings (MRI) were undertaken. RESULTS: Nineteen (67%) patients reported audiovestibular symptoms. Sensorineural hearing loss was found in 6 (21%) patients. Abnormal results on ENG were significantly higher (50%) (P < 0.01). Abnormal laboratory data were available from 26 patients (P < 0.05). MRI did not show any pathosis. CONCLUSION: The audiovestibular disturbances in SLE are more prevalent than previously recognized. Although no cause and effect relationship can be established by this type of study, it appears that a relationship exists. SIGNIFICANCE: Audiologic research should be directed toward routine, pure tone audiometry, and ENG assessment for patients with SLE to enable crucial treatment.  相似文献   
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BACKGROUND: The adverse effects of elevated intraabdominal pressure (IAP) on abdominal organs are realized, but its influence on anastomotic healing has not been studied. The aim of this study was to evaluate the effect of elevated IAP on healing of colonic anastomoses. METHODS: Thirty rats, which all had right colonic anastomoses, were divided into five groups. Group 1 was the control group, and group 2 had fecal peritonitis. IAP was maintained between 4 to 6 mm Hg in group 3, 8 to 12 mm Hg in group 4, and 14 to 18 mm Hg in group 5 until all rats were sacrificed on day 4. Bursting pressures and tissue hydroxyproline concentrations of anastomoses were then analyzed and compared. RESULTS: Mean +/- SEM of bursting pressures were 143+/-2.9 mm Hg in group 1, 72+/-14.4 mm Hg in group 2, 77.3+/-7.9 mm Hg in group 3, 57.5+/-11.2 mm Hg in group 4, and 40.1+/-9.6 mm Hg in group 5 (P<0.0001, one-way analysis of variance [ANOVA]). Mean +/- SEM of tissue hydroxyproline concentrations were 5.3+/-0.3 microg/mg in group 1, 4.7+/-0.5 microg/mg in group 2, 4.6+/-0.6 microg/mg in group 3, 3.6+/-0.5 microg/mg in group 4, and 2.4+/-0.2 microg/mg in group 5 (P = 0.0026, one-way ANOVA). The bursting pressure and hydroxyproline concentrations had good correlation (P<0.001, r = 0.76). CONCLUSIONS: Elevated IAP delays healing of colonic anastomoses and 4 to 6 mm Hg IAP delays healing as much as fecal peritonitis. More elevated IAP delays healing more than fecal peritonitis. These events may be clinically important and may result from local-systemic effects of IAP.  相似文献   
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Microbial keratitis following penetrating keratoplasty.   总被引:2,自引:0,他引:2  
PURPOSE: To investigate the prevalence of microbial keratitis, predisposing risk factors and treatment modalities in patients who developed keratitis following penetrating keratoplasty (PK). PATIENTS AND METHODS: The records of 285 patients who had undergone PK between January 1991 and December 1995 in a tertiary care center were reviewed. Patients who developed postoperative microbial keratitis were evaluated for predisposing risk factors, microbiological etiology, response to broad spectrum antibiotic therapy and subsequent PK. Patients were mainly treated with fortified topical antibiotics with or without repeat PK. RESULTS: Of the 285 patient records reviewed, microbial keratitis developed in 21 eyes of 21 patients (7.4%). Seventy-one percent of infections occurred within 6 months after grafting. Keratitis initially began from the donor-recipient border in 16 cases (76.2%) and were central or paracentral in 5 patients. Predisposing risk factors included loose or exposed suture (9), suture removal (1), persistent epithelial defect (3), graft failure (3), contact lens wear (1), Stevens-Johnson syndrome (1). Fifteen (71.4%) patients were culture-positive consisting of Streptococcus pneumoniae (7), Staphylococcus aureus (5), Pseudomonas aureginosa (2), and Hemophilus influenzae (1). Forty-three percent of patients were successfully treated with medical therapy only. Seven patients underwent second PK for visual rehabilitation and 4 for tectonic purposes. After medical and surgical therapy, graft clarity was achieved in 17 (81%) of patients. CONCLUSIONS: The microbial keratitis following PK is a major postoperative problem affecting the long term prognosis. Careful selection of patients, and preoperative and postoperative control of risk factors, may decrease the frequency of this complication. Several factors, including loose or exposed sutures, epithelial defects, ocular surface disorders, and graft failure, may predispose patients to develop microbial keratitis following PK.  相似文献   
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There is increasing evidence about the involvement of eosinophils in the pathogenesis of inflammatory bowel disease. We report here two patients with ulcerative colitis who were initially diagnosed as eosinophilic colitis based on histopathological examination during their first attacks. They had symptomatic improvement with ketotifen and metronidazole during their first attacks. However, subsequent attacks which were histopathologically diagnosed as ulcerative colitis did not resolve with the above-mentioned treatment and necessitated a treatment with 5-ASA agents plus corticosteroids. Azathioprine also had to be added in the treatment of the second patient. Dense eosinophilic infiltration in these cases may suggest a role of eosinophils in the initiation of attacks in some ulcerative colitis patients.  相似文献   
9.
C-reactive protein and coronary heart disease in western Turkey   总被引:9,自引:0,他引:9  
C-reactive protein (CRP) has been recognized as a useful marker for coronary or cardiovascular risk in healthy subjects or patients with coronary heart disease (CHD) in industrialized societies. We assessed whether CRP could serve as a marker of prevalent CHD risk in a cross-sectional study of a population with low cholesterol levels (4.61 mmol/L in men and 4.82 mmol/L in women) but higher prevalence of other risk factors. In 1,046 participants of the Turkish Adult Risk Factor Survey in 2000, high-sensitivity CRP as well as other risk variables were evaluated, and CHD was diagnosed, based on clinical findings and Minnesota coding of electrocardiograms at rest. Almost an equal number of men and women > or = 30 years of age constituted the population sample of the western regions of Turkey. Geometric mean value of CRP was 1.9 mg/L (interquartile range 0.8 to 4.3), without revealing a significant difference in gender. CRP was correlated with many variables, notably those involving central obesity, fibrinogen, and apolipoprotein-B, but not with smoking status (regardless of age adjustment). In multiple regression models, blood fibrinogen, waist circumference, total cholesterol, and physical activity grade were independently associated with log CRP concentrations. Among many risk variables, CRP quartiles and systolic blood pressure were, besides age and gender, the only significant independent determinants of CHD. The age-adjusted odds ratio for CHD in the highest as opposed to the lowest quartile was 4.48 (p < 0.001). Even after adjustment for the 5 previously mentioned determinants of CRP, a 4.2-fold increased risk of CHD still persisted between the highest and lowest quartiles. Thus, the observed increased risk was not in large part due to the intermediary effects of fibrinogen, nor were some indicators of insulin resistance, but interaction appeared to be independent of these effects. Thus, CRP values serve as a marker of prevalent CHD risk in populations with low cholesterol levels. This association is independent of, or in addition to, the effects of conventional risk factors, suggesting that the contribution of chronic low-grade inflammation to the atherothrombotic process is present even in the setting of low cholesterol levels.  相似文献   
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Systemic sclerosis (SSc) is a disease characterized by skin and internal organ involvement. There is progressive accumulation of extracellular matrix components in the skin and involved organs. Tissue fibrosis is the prominent reason for mortality, and still, there is no satisfactory treatment. The aim of this study was to evaluate the effects of urotensin-II (U-II) antagonist palosuran in an animal model of scleroderma. We also planned to measure U-II, endothelin-1 (ET-1), and transforming growth factor-β1 (TGF-β1) levels, as well as the association of these levels with dermal thickness. Twenty-four male mice were included in this study and they were divided into three groups—group 1: control group, group 2: fibrosis group, and group 3: fibrosis + palosuran treatment group. Fibrosis + palosuran treatment in group 3 reduced ET-1, U-II, and TGF-β1 levels. In total, the diminished values were statistically significant in the ET-1 and TGF-β1 levels (p?<?0.05). Dermal thickness was higher in the fibrosis group, when compared with the other groups. There was no significant relationship between dermal thickness and ET-1, U-II, or TGF-β1 levels (p?>?0.05). It is believed that U-II is an important mediator in SSc, and its antagonism with palosuran could be a new treatment choice in SSc.  相似文献   
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