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81.
OBJECTIVE: To determine the morphologic characteristics of the nonciliated epithelium found in chondroid hamartoma of the lung. STUDY DESIGN: The morphologic characteristics and immunohistochemical reaction for surfactant protein A of the nonciliated epithelium in chondroid hamartoma of the lung was studied by immunohistochemistry. Alveolar epithelium in normal lung tissue and lung tissue surrounding primary lung cancer or metastatic lung lesions was used as a control. RESULTS: In all cases, the nonciliated epithelium in chondroid hamartoma showed the morphologic criteria of hyperplastic alveolar type II cells and a very strong positive surfactant protein A reaction in the cytoplasm when compared with alveolar epithelium of the normal lung. Similar hyperplastic type II cells were also found in the alveolar lung around metastatic or primary lung tumors. CONCLUSION: These findings may indicate that the nonciliated cells found in chondroid hamartoma of the lung are hyperplastic type II cells. This suggests that the alveolar epithelium found in chondroid hamartoma of the lung is a secondary reaction around the hamartoma and not a primary component of the lesion.  相似文献   
82.
A new affinity gel for purification of carbonic anhydrase isozymes was prepared using EUPERGIT C-250L derivatized with p-aminobenzenesulfonamide, an inhibitor of carbonic anhydrase. The binding capacity of the affinity gel was determined at different temperatures, pH values, elution buffers, and ionic strengths. Human carbonic anhydrase isozymes (HCA I and HCA II) and bovine carbonic anhydrase (BCA) were purified in high yields from erythrocytes.  相似文献   
83.
Reoxygenation of the ischemic tissue promotes the generation of various reactive oxygen metabolites (ROM) which are known to have deleterious effects on various cellular functions. This study was designed to determine the possible protective effect of mesna (2-Mercaptoethane Sulfonate) on renal ischemia/reperfusion (I/R) injury. Wistar albino rats were unilaterally nephrectomized, and 15 days later they were subjected to 45 min of renal pedicle occlusion followed by 6 h of reperfusion. Mesna (MESNA, 150 mg/kg, i.p.; an effective dose against I/R injury) or vehicle was administered twice, 15 min prior to ischemia and immediately before the reperfusion period. At the end of the reperfusion period, rats were killed by decapitation. Kidney samples were taken for histological examination or determination of the free radicals, renal malondialdehyde (MDA) and glutathione (GSH) levels, and myeloperoxidase (MPO) activity. Renal tissue collagen content, as a fibrosis marker was also determined. Creatinine and urea concentrations in blood were measured for the evaluation of renal function. The results demonstrated that renal I/R caused nephrotoxicity, as evidenced by increases in blood urea and creatinine levels, which was reversed by MESNA treatment. Increased free radical levels, as assessed by nitroblue-tetrazolium test were reduced with MESNA. Moreover, the decrease in GSH and increases in MDA levels, and MPO activity induced by I/R indicated that renal injury involves free radical formation. Treatment of rats with MESNA restored the reduced GSH levels while it decreased MDA levels as well as MPO activity. Increased collagen contents of the kidney tissues by I/R were reversed back to the control levels by MESNA treatment. Since MESNA administration reversed these oxidant responses, improved renal function and microscopic damage, it seems likely that MESNA protects kidney tissue against I/R induced oxidative damage.  相似文献   
84.
Several genes encoding for different cytokines may play crucial roles in host susceptibility to tuberculosis (TB), since the cytokine production capacity varies among individuals and depends on the cytokine gene polymorphism. The association of the cytokine gene polymorphisms with the development of TB was investigated in this study. DNA samples were obtained from a Turkish population of 81 patients with the different clinical forms of TB, and 50 healthy control subjects. All genotyping (IL-6, IL-10, IFN-gamma, TGF-beta and TNF-alpha) experiments were performed using sequence-specific primers PCR (PCR-SSP). Analysis of allele frequencies showed that IL-10 -1082 G allele frequency was significantly more common in TB patients than healthy controls (37.7% vs 23.0%, p: 0.014). No statistically significant differences were observed between the different clinical forms of the disease. These results suggest that the polymorphisms in IL-10 gene may affect susceptibility to TB and increase risk of developing the disease. To confirm the biological significance of our results, further studies should be performed on other population groups.  相似文献   
85.
In the present study, the relationship between exopolysaccharide production and cholesterol removal rates of five strains of Lactobacillus delbrueckii subsp. bulgaricus isolated from home‐made yoghurt was studied. Test strains were selected according to their exopolysaccharide production capacity. Influence of different bile concentrations on cholesterol removal was investigated. It was confirmed that B3, ATCC 11842 and G11 strains which produce high amounts of exopolysaccharide (211, 200 and 159 mg/l, respectively) were able to remove more cholesterol from the medium compared to those that produce low amounts of exopolysaccharide (B2, A13). The highest cholesterol removal (31%) was observed by strain L. delbrueckii subsp. bulgaricus B3, producing a high amount of exopolysaccharide, in 3 mg/ml bile concentration. Cholesterol removal by resting and dead cells was investigated and it was found to be 4%–14% and 3%–10%, respectively. Cholesterol removal by immobilized and free cells of the B3 strain was studied and it was determined that immobilized cells are more effective. Influence of cholesterol on exopolysaccharide production has also been tested and it was found that cholesterol increased the production of EPS. The results indicated that: (i) there is a correlation between cholesterol removal and EPS production; and (ii) L. delbrueckii subsp. bulgaricus B3 is regarded as a suitable candidate probiotic and adjunct culture.  相似文献   
86.
The efficacy of low‐toxicity chemicals as possible alternatives to synthetic fungicides for the control of Uromyces appendiculatus and Puccinia triticina was evaluated. A preliminary selection of food additives was performed through in vitro and in vivo preliminary screenings. The ED50 and minimum inhibition concentration (MIC) values showed that most of the food additives used in this study were more toxic to U. appendiculatus than to P. triticina. Acetic acid, potassium carbonate, sodium carbonate and sodium molybdate were the food additives that were more toxic to the urediniospores of P. triticina. Selected compounds and concentrations were tested on bean and wheat plants grown in pots under controlled conditions. Acetic acid, ammonium bicarbonate, potassium acetate, potassium benzoate, potassium bicarbonate, potassium carbonate, sodium acetate and sodium citrate at 0.03, 0.09, 0.03, 0.006, 0.012, 0.012, 0.03 and 0.03 m , respectively, significantly reduced the disease severity of U. appendiculatus without causing any injury to bean leaves. Ammonium bicarbonate, potassium bicarbonate, sodium bicarbonate and sodium citrate at 0.12, 0.03, 0.12 and 0.03 m , respectively, were the most effective in reducing the disease severity caused by P. triticina without causing any injury to wheat leaves.  相似文献   
87.
The antimicrobial effects of sodium benzoate against Enterococcus faecalis and Enterococcus faecium were investigated. The MIC(90) of sodium benzoate were 64 mg/L for E. faecalis and 32 mg/L for E. faecium, while the MBC(90) were 128 mg/L and 64 mg/L, respectively. Although further studies are required for clinical evidence, sodium benzoate seems to be effective against Enterococcus spp.  相似文献   
88.
A new species of parasitic nematode, Neoascarophis macrouri n. sp. (Cystidicolidae), is described from the stomach and stomach wall of the marine deep-water fish Macrourus berglax (onion-eye grenadier) in the eastern Greenland Sea (North Atlantic Ocean). The new species, studied using both light and scanning electron microscopy, is characterised mainly by the location of the vulva near the posterior end of the body (a short distance anterior to the anus), non-filamented eggs, the structure of the mouth, a short vestibule and the length of the spicules (567-615 and 144-156 mum). Metabronema insulanum Solov'eva, 1991 is transferred to Neoascarophis as N. insulana (Solov'eva, 1991) n. comb.  相似文献   
89.
A new species of parasitic nematode, Neoascarophis macrouri n. sp. (Cystidicolidae), is described from the stomach and stomach wall of the marine deep-water fish Macrourus berglax (onion-eye grenadier) in the eastern Greenland Sea (North Atlantic Ocean). The new species, studied using both light and scanning electron microscopy, is characterised mainly by the location of the vulva near the posterior end of the body (a short distance anterior to the anus), non-filamented eggs, the structure of the mouth, a short vestibule and the length of the spicules (567–615 and 144–156 μm). Metabronema insulanum Solov’eva, 1991 is transferred to Neoascarophis as N. insulana (Solov’eva, 1991) n. comb.  相似文献   
90.
Drug-induced liver toxicity is a common cause of liver injury. This study was designed to elucidate whether high dose vancomycin (VCM) induces oxidative stress in liver and to investigate the protective effects of erdosteine, an expectorant agent. Twenty-two young Wistar rats were divided into three groups as follows: control group, VCM, and VCM plus erdosteine. VCM was administered intraperitoneally in the dosage of 200 mg/kg twice daily for 7 days. Erdosteine was administered orally administered once a day at a dose of 10 mg/kg body weight. The activities of antioxidant enzymes such as superoxide dismutase and catalase as well as the concentration of malondialdehyde, as an indicator of lipid peroxidation, were measured to evaluate oxidative stress in homogenates of the liver. VCM administration increased malondialdehyde levels (p < 0.001), superoxide dismutase (p < 0.01) and catalase (p < 0.001) activities. Erdosteine co-administration with VCM injections caused significantly decreased malondialdehyde levels (p < 0.001), superoxide dismutase (p < 0.01) and catalase (p < 0.001) activities in liver tissue when compared with VCM alone. It can be concluded that erdosteine may prevent VCM-induced oxidative changes in liver by reducing reactive oxygen species.  相似文献   
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