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As free radicals and lipid peroxidation are involved in the pathogenesis of different inflammatory diseases of the liver, the blood malondialdehyde content, the activity or quantity of free radical eliminating enzymes and the natural antioxidant, vitamin E serum level has been studied in ten patients with chronic active hepatitis and in six subjects with alcoholic liver disease. Thirty healthy volunteers served as controls. The serum malondialdehyde/thiobarbituric acid reactive substance and its concentrations increased significantly in both hepatitis groups. The superoxide dismutase content was also raised in the patients' sera. The serum glutathione peroxidase (GSH-Px) activity was decreased in both groups, while the red blood cell GSH-Px showed a significantly lower activity in the alcoholic hepatitis patients. Serum catalase activity and vitamin E levels in both types of chronic hepatitis were not significantly different from the healthy controls.  相似文献   
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Objective: The aim of the study was to investigate whether or not esuprone binds substantially to MAO-A in the human brain. Methods: In a randomised double-blind placebo-controlled study 16 male healthy volunteers were examined␣with positron emission tomography (PET) with [11C]harmine. Eight of the volunteers were given daily doses of 800 mg esuprone, four were given bi-daily doses of 300 mg moclobemide, and four volunteers were given placebo tablets. PET was performed before initiation of a 7-day treatment period. On day 7, one investigation was made immediately before administration of the drug, representing 23 h after the previous day's treatment for esuprone and 11 h after the last tablets of moclobemide. Further investigations were made 4 h and 8 h after the morning dose on day 7. Results: PET showed a high degree of binding of [11C]harmine, a high-affinity ligand for MAO-A, before the start of treatment, and a marked and similar reduction after treatment with esuprone and moclobemide. A slight tendency for normalisation of enzyme binding was observed at the last time point. In the placebo group no change was observed. Plasma kinetics of esuprone showed a rapid elimination with a half-life of about 4 h. Conclusion: The study demonstrates that esuprone was comparable to moclobemide in its effect on MAO-A inhibition in the brain at the doses given. This is an illustration of the potential of PET to monitor drug effects directly on target biochemical systems in the brain in human volunteers, and the possibility of using these data, rather than pharmacokinetic data, for the determination of dosing intervals. Received: 21 August 1996 / Accepted in revised form: 22 November 1996  相似文献   
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In experiments on adult, female rats, the author confirm the stimulatory effect of 50 micrograms kg-1 17-beta-estradiol daily, s.c., for more than 1 week on the activity of liver tyrosine aminotransferase and tryptophan pyrrolase and describe experiments suggesting an increased glucocorticoid sensitivity, as a consequence of the estrogen treatment. The study contributes to the information on potential side effects of hormonal contraception.  相似文献   
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PURPOSE: To report on iodine-125 ((125)I) interstitial irradiation in the treatment of brain stem tumors. PATIENTS AND METHODS: Two patients with brain stem tumors were treated with CT- and image fusion-guided (125)I stereotactic brachytherapy. RESULTS: By March 2003, the patients had been followed up for 47 and 13 months, respectively. In case 1, the tumor volume was 1.98 cm(3) on the control CT, indicating a 65.5% shrinkage as compared to a target volume of 5.73 cm3 at the time of brachytherapy. In case 2, shrinkage was more distinct. After irradiation, the cyst volume was 0.16 cm(3) on the control MRI, indicating a 97.4% shrinkage as compared to a target volume of 6.05 cm(3) at the time of brachytherapy, i. e., the metastasis had virtually disappeared. CONCLUSION: CT- and image fusion-guided (125)I stereotactic brachytherapy can be performed during the biopsy session. The procedure can be well planned dosimetrically and is surgically precise.  相似文献   
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In many cases, only a minute amount of partially degraded genomic DNA can be extracted from archived clinical samples. Diverse whole-genome amplification methods are applied to provide sufficient amount of DNA for comparative genome hybridization, single-nucleotide polymorphism, and microsatellite analyses. In these applications, the reliability of the amplification techniques is particularly important. In PCR-based approaches, the plateau effect can seriously alter the original relative copy number of certain chromosomal regions. To eliminate this distorting effect, we improved the standard degenerate oligonucleotide-primed PCR (DOP-PCR) technique by following the amplification status with quantitative real-time PCR (QRT-PCR). With real-time detection of the products, we could eliminate DNA overamplification. Probes were prepared from 10 different tumor samples: primary and metastatic melanoma tissues, epidermoid and bronchioloalveolar lung carcinomas, 2 renal cell carcinomas, 2 colorectal carcinomas, and a Conn and Cushing adenoma. Probes were generated by using nonamplified and amplified genomic DNA with DOP-PCR and DOP-PCR combined with QRT-PCR. To demonstrate the reliability of the QRT-PCR based amplification protocol, altogether 152 relative copy number changes of 44 regions were determined. There was 85.6% concordance in copy number alterations between the QRT-PCR protocol and the nonamplified samples, whereas this value was only 63.8% for the traditional DOP-PCR. Our results demonstrate that our protocol preserves the original copy number of different chromosomal regions in amplified genomic DNA than standard DOP-PCR techniques more accurately.  相似文献   
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320 patients with essential hypertension divided into three groups (minor, medium and major severty) were studied against 50 normal controls. Plasma renin activity (PRA) was estimated in case of normal and low Na intake, furthermore, of low Na intake in association with administration of chlorothiazide, in the recumbent position as well as at the end of 4-hr walk. The hypertensive group of medium severity (Group II) revealed a significant decrease in PRA, compared with the controls and with the hypertensive group of minor severity (Group I), in each period of observation. A significant increase of PRA in response to insulin hypoglycaemia was demonstrable in all three groups and in the controls, but the increase was of significantly lesser degree in Group II than either in the controls or in Group I. The plasma catecholamine concentrations were found lower in Group II than in the controls and in Group I. An elevation of the plasma catecholamine levels was demonstrable in response to insulin hypeglycaemia, but it was of lesser degree in Group II than a Group I and in the controls. The poor responsiveness of the RAS in Group II is attributed to an inadequate adrenergic activity and to an increased mean arterial pressure in that group, but the higher age of patients and longer duration of hypertensive disease, both characteristic of the group of medium severity, may also effect the renin-angiotensin system.  相似文献   
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