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This study aims at assessing the ability of asthma patients to defend themselves against the noxious effects of oxidative stress, known being the inflammatory nature of this disorder. As the anti-radical defence ability of the body is reflected by the antioxidative potential of blood and tissues, our study was based on the determination of the activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and CAT/SOD and GPx/SOD ratios in the blood. Except for SOD, the activity of which was lower in asthma patients by -34.08%, CAT and GPx had values increased by +32.18%, respectively, with a resulting increase of CAT/SOD and GPx/SOD ratios. Our data, demonstrating a change in per-oxidants/antioxidants balance in favour of the first ones, seem to suggest that in the treatment of bronchial asthma the association of some compounds with antioxidants effects would be beneficial.  相似文献   
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Vanadium, a transitional element belonging to Vb group is wide-spread both in vegetal and animal world. Although known by more a hundred years ago only in 1985 its hypoglycaemic properties were established. Recent research shown that the hypoglycaemic properties and the toxicity are influenced both by vanadium valence state and organic moiety that is binding it.  相似文献   
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Exist a statistically significant association between a diagnosis of coronary heart disease and certain oral health parameters. These parameters are independent and more strongly associated with coronary heart disease than were recognized risk factors, such as serum cholesterol levels, body mass index, diabetes and smoking status. The correlation between serum and salivary cholesterol concentration and the role of salivary lipids in oral health have been poorly characterized. Lipids in saliva are mostly glandular in origin, through some may diffuse diffuse directly from the serum. The surface of the enamel (in case of dietary fat which have an cariostatic effect) is protected against demineralization by a mixture of salivary lipids and proteins. Salivary lipids may have anucleating role in the early mineralization of the dental plaque. The prevalence of periodontal disease may be increased in patients with atherosclerosis, and dental and periodontal infections have been shown to be associated with occurrence of acute and chronic coronary heart disease. Among the known risk factors of atherosclerosis, high serum lipid levels, especially cholesterol may be important with regard to periodontal health.  相似文献   
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The dishomeostazical theory (etiopathogenic integrative concept) allows an ample and complex vue on the stomatognathic system dysfunctional syndrome, because it begins from the perception of the stomatognathic system (SS) as a whole in which the alteration of each element can induce the disfunction of the entire system. The purpose of this study is to demonstrate that the neuroendocrine suprasystemic factor (STH hypersecretion on adult organism) disturbs every element of the SS and induces an important alteration of the fundamental cranio-mandibular relations.  相似文献   
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Objective: To improve the specificity and sensitivity of prostatic cancer detection, we prospectively evaluated total prostate specific antigen (PSA) level, PSA density, free-to-total PSA ratio and a new formula called prostate malignancy index (PMI) as a discriminator of prostate cancer in patients with intermediate PSA levels and normal digital rectal examinations. Materials and methods: Between November 1995 and October 1997, 95 patients who had serum PSA levels of 4.0 to 10.0 ng/ml with normal digital rectal examinations were prospectively evaluated. All patients underwent one or two times transrectal ultrasound guided prostate biopsies. Based on age specific reference range of PSA, PSA density and % free PSA ratio, PMI was calculated for each patient. The free and total serum PSA concentrations were determined by an Immulite assay system. (Diagnostic Product Corp., Los Angeles, California). Results: Overall 20 of 95 (21%) patients had prostate cancer. There were no significant differences in patient mean age and mean total PSA between those with benign and those with malignant biopsies (p>0.05). However, there were significant differences in mean PSAD, mean free-to-total PSA ratio and mean PMI (p<0.01, p<0.05, p<0.01, respectively). Benign condition specificities for PM index, percent free PSA, PSA density and total PSA at a 90% sensitivity for prostate cancer were 48%, 10.6%, 8% and 4%, respectively. Of 95 patients, 27 (28.4%) had a PMI of equal or more than 3.1, including 12 of 75 (16%) with negative biopsy and 15 of 20 (75%) with positive biopsy. Furthermore a cutoff MI 0.86 P correctly identified 24% of benign cases without missing any prostate cancer cases. The comparison of receiver operating characteristic (ROC) curve areas showed that PMI was better than total PSA (p<0.01). Although, the area under the ROC curve of % free PSA and PSAD were higher than the area of total PSA, these differences were not statistically significant (p>0.05). Conclusions: We concluded that the prostate malignancy index could be utilized to differentiate benign conditions from prostate cancer in patients with intermediate PSA levels and normal digital rectal examination. Also significant numbers of negative biopsies can be prevented in these patients.  相似文献   
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Objectives: To investigate the correlation of nuclear p53 accumulation with disease outcome in a cohort of patients with transitional cell carcinoma of the bladder. Methods: A total of 90 patients (11 female, 79 male) with transitional cell carcinoma of the bladder were included in this study. Tumour samples from the primary tumour were analysed by immunohistochemistry for nuclear accumulation of p53 protein. Outcome of each patient was recorded and investigated for a possible relation with p53 status. Results: Nuclear p53 deposition was determined in 22 specimens. The nuclear p53 deposition was seen in less than 20% of the nuclei examined in 13 and more than 20% in 9 cases. No stromal staining was observed. Nuclear p53 deposition was present in 15.2% (7/46) of grade 2 tumours, and 34% (15/44) of grade 3 tumours (p=0.037). Stage distribution revealed 15.5% (5/33) positivity in stage pTa, 25.8% (8/31) in pT1 and 34% (9/26) in stage pT2–3 tumours. Tumours with p53 nuclear accumulation had a higher rate of recurrence and progression and shorter survival. Conclusion: Results of the current study indicate p53 as an important factor in determination of biological behaviour of bladder cancer.  相似文献   
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