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941.
A Gosiewska I Kinalska W Zarzycki M Górska I Borejszo 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1992,47(1-2):28-30
In 110 diabetics type I and type II and in 30 control subjects the total serum activity of NAG as well as of its isoenzymatic forms A and B was determined. In cases with diabetic nephropathy the GFR and serum creatinine was also analysed. It was found that NAG activity is correlated to the degree of clinical symptoms of diabetic vascular changes. Therefore it could be suggested that NAG plays a role in development of microangiopathy. NAG determination may also serve as an index differentiating the diabetic microangiopathy from other forms of microvessels. 相似文献
942.
G Aboagye-Mathiesen F D Tóth A M Dalsgaard P M Petersen V Zachar P Ebbesen 《Preparative biochemistry》1992,22(2):105-121
Human placental trophoblasts, fibroblasts and the trophoblast-derived malignant cell JAR are potent producers of interferons (IFNs) when stimulated with Sendai virus. The three cell lines produced different levels and compositions of IFN-alpha subtypes and IFN-beta. Anti-IFN globulins, Cibacron Blue F3GA and Concanavalin A were covalently immobilized on pressure-stable, macroporous polymeric matrices derivatized with vinyl sulphone (HEMA-BIO 1000 VS and HEMA 1000 VS). These supports were packed in biocompatible PEEK columns and were coupled with switching valves, to develop a tandem high-performance affinity chromatographic (HPAC) method for the isolation, purification and biochemical characterization of the IFNs produced in Sendai virus-stimulated human placental trophoblasts, fibroblasts and trophoblast-derived malignant cell, JAR, cultures. Silver-stained SDS-PAGE and gel densitometric analysis revealed the purity of the purified proteins to be between 94 and 98%. Specific activities of the purified IFNs ranged between 0.37-2.76 x 10(8) IU/mg of protein with cumulative recoveries between 90 and 92.2%. The purified IFN components exhibited quantitatively different antiviral activities in human and bovine cell lines. The utility of the tandem method for the purification and characterization of human type 1 IFNs produced from other cell lines are also discussed. 相似文献
943.
C E Gil-Rodrigo B Gáldiz M Carou J M Gandarias R Gómez A Vallejo L F Ainz 《Revista Espanola de Fisiología》1992,48(1):31-36
The influence of adenosine 5'-triphosphate on gastric acid secretion stimulated by histamine, carbachol, dibutyryl-cAMP and the phosphodiesterase inhibitors 8-phenyl-theophylline and rolipram in isolated rabbit gastric glands was studied. Changes oi gastric acid secretion were measured by the aminopyrine accumulation method. Histamine-stimulated acid secretion was significantly inhibited by ATP 1 mM, whereas the secretory responses elicited by carbachol, dibutyryl-cAMP, 8-phenyl-theophylline or rolipram were not. Assays with indomethacin, a well known prostaglandin synthesis inhibitor, showed that this agent significantly reduced the inhibitory effect of ATP on histamine responses. The results indicate that the antisecretory effect of ATP was specific for histamine and that it was mediated, at least in part, via stimulation of endogenous prostaglandin production. 相似文献
944.
M López-Torres R Pérez-Campo C Rojas C Barja de Quiroga 《Revista Espanola de Fisiología》1992,48(3):191-196
Lipid peroxidation in rat liver and brain has been studied to see if it increases with old age. No significant differences in the level of endogenous, nonstimulated lipid peroxidation (TBA-RS) is found between 9 month-old (mature adults) and 28 month-old animals in liver or cerebral cortex. Liver homogenates subjected in vitro to an oxidative stress (ascorbate-Fe++), show a clearly slower peroxidation rate in old than in young animals. On the other hand, the in vitro peroxidation rate of cerebral homogenates was similar in young and old animals. The in vitro peroxidation rate was much higher in brain than in liver tissue. These results do not support the view that old rats liver and brain are more susceptible to free radical oxidative damage than those of young ones. 相似文献
945.
A study has been made in everted sacs of guinea pig jejunum to see if the two transport systems of glucose analogues characterized at the brush border membrane vesicles are operative. The transport kinetics of D-galactose and alpha-methylglucoside up to 80 mM concentrations has been studied, as well as the mutual inhibitions between them at low and high concentrations of the substrate and at different concentrations of the inhibitor. Low temperature (20 degrees C) inhibits galactose transport at 0.1 mM (70%) and 40 mM (78%) concentrations. A mass transfer coefficient, KD, somewhat higher for galactose than for alpha-methylglucoside, was obtained when the transport component was abolished by phlorizin. The transport of D-galactose and alpha-methylglucoside seemed to be compatible with the function of one system shared by both substrates, which presents greater affinity for alpha-methylglucoside. The functional existence of two systems of active transport at the brush border of guinea pig was not evidenced in intestinal preparations of whole tissue, due perhaps to the effect of the unstirred water layers. However, differences in KD values and some results of the mutual inhibitions may suggest a second system. 相似文献
946.
E Mu?oz-Martínez M T Unzaga A Agis M E López-Oliva 《Revista Espanola de Fisiología》1992,48(2):121-126
In order to observe the effects of sheep red blood cells (SRBC) administration on the muscle cell growth in malnourished states, adult male Wistar rats (135 +/- 10 g 10 animals per group) subjected during 30 days to 1% and 10% protein diets, were injected (i.v.) either 15.5 x 10(8) sheep red blood cells or 0.5 ml saline/100 g b.w. after 20 days of experiment. On the 10th day after injection the animals were sacrificed and the gastrocnemius muscle was removed, weighed and homogenized. The supernatant fluids were used to evaluate muscle protein, DNA and RNA rates and acid DNase activity. All parameters were depleted in malnourished rats, indicating a muscle cellular atrophy as well as a decrease in muscle protein synthesis per DNA-unit. Muscle hyperplasia and hypertrophy were found in antigenically stimulated rats fed 10% protein against non-stimulated control. In contrast, muscle growth in protein-deficient rats SRBC-treated was unmodified when compared to non-stimulated malnourished muscle, although RNA functionality seems to be enhanced (RNA/DNA). These data suggest that a redistribution of essential nutrients occurred for muscle growth adaptation rather than for defensive mechanism. 相似文献
947.
Genomic in situ hybridization to identify alien chromosomes and chromosome segments in wheat 总被引:15,自引:0,他引:15
T. Schwarzacher K. Anamthawat-Jónsson G. E. Harrison A. K. M. R. Islam J. Z. Jia I. P. King A. R. Leitch T. E. Miller S. M. Reader W. J. Rogers M. Shi J. S. Heslop-Harrison 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1992,84(7-8):778-786
Summary Genomic in situ hybridization was used to identify alien chromatin in chromosome spreads of wheat, Triticum aestivum L., lines incorporating chromosomes from Leymus multicaulis (Kar. and Kir.) Tzvelev and Thinopyrum bessarabicum (Savul. and Rayss) Löve, and chromosome arms from Hordeum chilense Roem. and Schult, H. vulgare L. and Secale cereale L. Total genomic DNA from the introgressed alien species was used as a probe, together with excess amounts of unlabelled blocking DNA from wheat, for DNA:DNA in-situ hybridization. The method labelled the alien chromatin yellow-green, while the wheat chromosomes showed only the orange-red fluorescence of the DNA counterstain. Nuclei were screened from seedling root-tips (including those from half-grains) and anther wall tissue. The genomic probing method identified alien chromosomes and chromosome arms and allowed counting in nuclei at all stages of the cell cycle, so complete metaphases were not needed. At prophase or interphase, two labelled domains were visible in most nuclei from disomic lines, while only one labelled domain was visible in monosomic lines. At metaphase, direct visualization of the morphology of the alien chromosome or chromosome segment was possible and allowed identification of the relationship of the alien chromatin to the wheat chromosomes. The genomic in-situ hybridization method is fast, sensitive, accurate and informative. Hence it is likely to be of great value for both cytogenetic analysis and in plant breeding programmes. 相似文献
948.
949.
E Podgórska 《Acta microbiologica Polonica》1992,41(1-2):97-107
Penicillium expansum has been grown on Capek-Dox medium using glucose and fructose as carbon source. Preservatives used in fruit processing and introduced in the medium were sorbic acid, formic acid, benzoic acid, SO2 and saccharose. Sulphur dioxide had a most inhibitory effect on mycelium growth and patulin production, formic acid concentration of 0.025% increased the amount of patulin by about 30% as compared to the culture with no preservatives. However its higher concentrations inhibited synthesis of this mycotoxin. Sorbic acid concentration of 0.1% stimulated the fungus strains examined in patulin synthesis but its highest amounts were detected using 0.0125% benzoic acid increased patulin secretion from 8 to 50% as compared to the control, depending on the strain examined. Saccharose concentration up to 50% clearly decreased patulin content in the medium until its total disappearance. 相似文献
950.
Summary Papain was able to catalyze the one-step synthesis of Gly-Gly-PheNH2, from N-unprotected amino acid derivatives. Maximum synthetic activity was obtained for a pH value of 6.5 and for a ]PheNH2]/[Gly-GlyOEt] ratio of 6. The presence of an organic cosolvent, such as ethylene glycol, influenced the synthetic activity. Synthetic yield was higher than 65% for a 12.5 M cosolvent concentration. 相似文献