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101.
An unusual cystine stone that occur only in patients, who have cystinuria is presented in 24-year-old man. Radiographs showed a giant bladder stone shadow, 8.0 x 10.0 x 5.0 cm in size. The literature was reviewed to identify the giant stones as well as the huge cystine stone which is exceptional yet as.  相似文献   
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Concentrations of metals were determined in the gills, liver, kidney, heart and muscle in Capoeta umbla caught from six stations from the Munzur River system. Metal concentrations in the tissues tended to vary significantly among stations (p < 0.05). Liver (Cu, 10.10 ± 0.23–23.03 ± 9.37 ppm; Zn, 14.67 ± 3.01–21.82 ± 2.39 ppm; Cd, 18.04 ± 4.56–52.69 ± 10.65 ppb and Fe, 28.87 ± 6.78–115.11 ± 34.87 ppm) and kidney (Cu, 1.80 ± 0.25–3.70 ± 0.62 ppm; Zn, 20.81 ± 0.37–29.36 ± 0.70 ppm; Cd, 132.06 ± 5.29–639.51 ± 20.14 ppb and Fe, 24.40 ± 1.98–59.39 ± 1.97 ppm) tissues showed higher metal concentrations than other tissues. It seems that metal contamination in the river is too high for the health of fish and the people who eat them. The geographical locations of catch, season, nature of diet, and the size of fish used for analyses might lead to different metal concentration in the same fish species.  相似文献   
104.
α-Lipoic acid (ALA) has been termed the 'ideal' antioxidant, a readily absorbed and bioavailable compound capable of scavenging a number of free radicals, and it has been used for treating diseases in which oxidative stress plays a major role. The present study was designed to gain a better understanding for the positive effects of ALA on the models of acute and chronic inflammation in rats, and also determine its anti-oxidative potency. In an acute model, three doses of ALA (50, 100 and 200?mg/kg) and one dose of indomethacin (25?mg/kg) or diclofenac (25?mg/kg) were administered to rats by oral administration. The paw volumes of the animals were calculated plethysmometrically, and 0·1?ml of 1?% carrageenan (CAR) was injected into the hind paw of each animal 1?h after oral drug administration. The change in paw volume was detected as five replicates every 60?min by plethysmometry. In particular, we investigated the activities of catalase, superoxide dismutase (SOD), glutathione S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR), inducible NO synthase (iNOS) and myeloperoxidase (MPx), and the amounts of lipid peroxidation (LPO) or total GSH in the paw tissues of CAR-injected rats. We showed that ALA exhibited anti-inflammatory effects on both acute and chronic inflammations, and a strongly anti-oxidative potency on linoleic acid oxidation. Moreover, the administration of CAR induced oedema in the paws. ALA significantly inhibited the ability of CAR to induce: (1) the degree of acute inflammation, (2) the rise in MPx activity, (3) the increases of GST and iNOS activities and the amount of LPO and (4) the decreases of GPx, GR and SOD activities and the amount of GSH. In conclusion, these results suggest that the anti-inflammatory properties of ALA, which has a strong anti-oxidative potency, could be related to its positive effects on the antioxidant system in a variety of tissues in rats.  相似文献   
105.
Resveratrol causes endothelium dependent and independent relaxation of vascular smooth muscle. This study investigated the mechanisms behind the effect of resveratrol on vascular tone. Resveratrol (0.1 mM) inhibited KCl-stimulated contractions in endothelium-denuded rat aorta and this inhibition was not reversed by tetraethylammonium (TEA) (5 mM), glyburide (3 microM), ouabain (0.1 mM), thapsigargin (1 microM), or indomethacin (10 microM). KCl (90 mM) increased the intracellular free calcium concentration ([Ca2+]i) in the isolated smooth muscle cells from the rat aorta and resveratrol (0.1 mM) did not inhibit the KCl-stimulated [Ca2+]i increase. The CaCl2 (0.1-100 microM) stimulated contractions were inhibited by resveratrol (0.1 mM) in the Triton X-100 skinned smooth muscle of the aorta. In heart valve endothelium, resveratrol (0.1 mM) augmented the acetylcholine (10 microM) stimulated [Ca2+]i increase. Resveratrol-induced augmentation of the acetylcholine-stimulated [Ca2+]i elevation was reversed by glyburide (3 microM), but not by TEA (5 mM). The present study indicated that resveratrol affected vascular smooth muscle and endothelium in different ways. Resveratrol decreased the Ca2+ sensitivity but did not affect the KCl-stimulated [Ca2+]i increase in the vascular smooth muscle. In the endothelial cells, resveratrol enhanced the agonist-stimulated [Ca2+]i increase that might trigger nitric oxide synthesis from endothelial cells.  相似文献   
106.
The development of human benign prostatic hyperplasia and its related signs and symptoms clearly requires a combination of testicular androgens and aging. Although the role of androgens as a causative factor for human benign prostatic hyperplasia is debated, they undoubtedly play at least a permissive role. The principle prostatic androgen is dihydrotestosterone. Two isoenzymes of 5-alpha reductase have been discovered. Type 2 is dominant in the genital issue. Testosterone is reduced by the 5-a reductase to dihydrotestosterone. Benign prostatic hyperplasia is predominantly due to stromal hyperplasia of the gland and affects more than 70% of men of 70 years or older with or without obstruction. Recent studies identified transforming growth factor-b, fibroblast growth factor and insulin-like growth factor family members as key regulators of cell proliferation and extracellular matrix turnover with interrelated activities. Furthermore, estrogens, andenergic signaling and inflammatory processes have been shown to have an impact. Without a solid understanding of the physiology and pathophysiology of benign prostatic hyperplasia it can be difficult to interpret the results of clinical trials and symptoms.  相似文献   
107.
Novel artificial neural network for early detection of prostate cancer.   总被引:3,自引:0,他引:3  
PURPOSE: Two artificial neural networks (ANN) for the early detection of prostate cancer in men with total prostate-specific antigen (PSA) levels from 2.5 to 4 ng/mL and from 4 to 10 ng/mL were prospectively developed. The predictive accuracy of the ANN was compared with that obtained by use of conventional statistical analysis of standard PSA parameters. PATIENTS AND METHODS: Consecutive men with a serum total PSA level between 4 and 10 ng/mL (n = 974) and between 2.5 and 4 ng/mL (n = 272) were analyzed. A separate ANN model was developed for each group of patients. Analyses were performed to determine the presence of prostate cancer. RESULTS: The area under the receiver operator characteristic (ROC) curve (AUC) was 87.6% and 91.3% for the 2.5 to 4 ng/mL and 4 to 10 ng/mL ANN models, respectively. For the latter model, the AUC generated by the ANN was significantly higher than that produced by the single variables of total PSA, percentage of free PSA, PSA density of the transition zone (TZ), and TZ volume (P <.01), but not significantly higher compared with multivariate analysis. For the 2.5 to 4 ng/mL model, the AUC of the ANN ROC curve was significantly higher than the AUCs for percentage of free PSA (P =.0239), PSA-TZ (P =.0204), and PSA density and total prostate volume (P <.01 for both). CONCLUSION: The predictive accuracy of the ANN was superior to that of conventional PSA parameters. ANN models might change the way patients referred for early prostate cancer detection are counseled regarding the need for prostate biopsy.  相似文献   
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The perception of dyspnoea differs between subjects with obstructive pulmonary diseases, partly because the underlying mechanisms for bronchoconstriction are different. We investigated the perception of bronchoconstriction in subjects with bronchiectasis, asthma and chronic bronchitis and possible contributing factors. Forty-seven non-smoking subjects with bronchiectasis, 50 subjects with asthma and 31 with chronic bronchitis were challenged with histamine. The Borg score was assessed before and after each challenge. The perception score corresponding to a fall in the forced expiratory volume in 1 s (FEV(1)) by 20% (PS(20)) was calculated. The mean values of DeltaBorg/DeltaFEV(1) (the Borg score change divided by the change in FEV(1) as a percentage of the baseline FEV(1)) and PS(20) of subjects with bronchiectasis and chronic bronchitis were significantly lower than in subjects with asthma after histamine challenge. The ratio of non-perceivers was higher in bronchiectasis (25.5%) and in chronic bronchitis (32.3%) than in asthma (4.0%). When all subjects were considered, DeltaBorg/DeltaFEV(1) values were significantly related to female sex ( r (2)=11.5%, P =0.0001), but not to age, duration of the disease, PD(20) or baseline FEV(1)%. The present study indicates that perception of histamine-induced bronchoconstriction is lower in patients with bronchiectasis and chronic bronchitis than in asthmatic patients, and that sex partially contributes to this difference.  相似文献   
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