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A Kálmán Z Kálmán G Vel?sy G Vargha G Vargha M Papp 《Acta physiologica Hungarica》1989,73(2-3):315-317
The aim of this study was to obtain more information on the serum level of "nonspecific pancreatic carboxylesterase" (PCE) in experimentally induced acute pancreatitis in rats. The effects of caerulein stimulation, hepatic duct ligation, bile-pancreatic duct ligation or the effect of retrograde injection of saline, 5% taurocholate and sunflower oil were investigated. The activity of PCE and amylase was measured in the serum, pancreatic tissue, pancreatic juice and ascitic fluid. The changes in PCE activity were greater (both in directions to increase or decrease) than that of amylase, produced by different experimental procedures. The results confirm the thesis that the serum activity of PCE is a more sensitive diagnostic method than that of amylase to detect the inflammatory process in the pancreas or the effect of obstruction of the pancreatic duct. 相似文献
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The present study was carried out to evaluate the suitability of the unstable white-zeste system in Drosophila melanogaster by testing 4 organophosphorus insecticides for potential genotoxic activity: dimethoate, fenitrothion, malathion, and methyl parathion. In view of the high sensitivity to insecticides of the unstable zeste strain used in this assay and the negative results obtained in this work, the white-zeste system does not appear to be sufficiently accurate for the evaluation of the mutagenic potential of specifically toxic chemicals, like insecticides. 相似文献
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P. Calo J. Cansado J. B. Velázquez C. Sieiro E. Longo T. G. Villa 《Biotechnology letters》1991,13(11):781-786
Summary Four strains ofLactobacillus plantarum, were tested for malolactic fermentation under conditions of variations in temperature, pH and SO2, L-malate and ethanol levels. When the pH value was below 3.5, malolactic fermentation was lower and was more sensitive to temperature changes. Malolactic fermentation decreased when the SO2 and ethanol levels were increased. The effects of L-malate levels were not significant. 相似文献
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E. Longo J. Cansado C. Sieiro P. Calo J. B. Velázquez T. G. Villa 《World journal of microbiology & biotechnology》1992,8(2):147-150
Fermentative behaviour and cell growth have been studied in grape juice inoculated either with two killerSaccharomyces cerevisiae wild strains or with their Acridine Orange-cured isogenic counterparts. The number of viable cells/ml at the beginning of the fermentation, as well as during exponential growth, were higher in grape juices inoculated with the cured strains. The CO2 production, fermentative rate and ethanol and acetic acid production were also higher in the cured strains, particularly during the stage of active fermentation. These differences, however, were minimal at the end of the fermentations. 相似文献
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To extend the data on the mutagenic effects of intercalating agents in Drosophila melanogaster, chloroquine and quinacrine were tested for the induction of genetic damage in D. melanogaster males. Sex-linked recessive lethals and sex-chromosome loss induction were studied following treatment of adult males using a feeding technique. Our results show that both intercalating compounds increase significantly the frequency of sex-linked recessive lethals, but are unable to induce sex-chromosome loss in male germ cells under the conditions of testing. 相似文献
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A phytosociological study of the juniper (locally called huito), pine (locally called sacch), pine-alder and fir forests of the Sierra de los Cuchumatanes and Cadena Volcánica in Guatemala was carried out. The Zürich-Montpellier approach was followed. In total 119 relevés were sampled and the data were organised in phytosociological tables to distinguish vegetation clusters. TWINSPAN was used to evaluate major differences among plant communities. Seven zonal plant communities were distinguished and described, namely: (1)Relbunium microphyllum-Agrostis tolucensis, (2)Werneria nubigena-Agrostis exserta, (3)Lachemilla vulcanica-Pinus hartwegii, (4)Holodiscus argenteus-Pinus hartwegii, (5)Hypnum cypressiforme-Juniperus standleyi, (6)Agave hurteri-Alnus firmifolia and (7)Sabazia pinetorum-Abies guatemalensis. This paper provides a thorough floristic characterisation of each community and outlines the major anthropogenic activities. To conclude, ecologic and floristic (dis)similarities between plant communities of the study area and those of Central Mexico, like the different altitudinal distribution of fir forests and the establishment of mid-successional communities such as theAgave hurteri-Alnus firmifolia were discussed. 相似文献
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Interspecies recombination In nature: a meningococcus that has acquired a gonococcal PIB porin 总被引:7,自引:0,他引:7
Julio A- Vázquez Sonsoles Berron Maria O'Rourke Gill Carpenter Edward Feil Noel H. Smith Brian G. Spratt 《Molecular microbiology》1995,15(6):1001-1007
A. vaginal isolate of Neisseria has been reported to resemble Neisseria meningitidis in biochemical characteristics but to react with serological reagents that are specific to the PI porin from Neisseria gonorrhoeae. We have confirmed that this isolate has the biochemical attributes of a meningococcus and have shown that it clusters among meningococcal Isolates on a dendrogram based on isoenzyme variation within housekeeping enzymes from populations of N. meningitidis and N. gonorrhoeae. Furthermore, the sequences of the fbp and adk genes were typical of those of N. meningitidis and were distinct from those of N. gonorrhoeae. However, the porB gene was very similar to the por genes of N. gonorrhoeae isolates that express the PIB class of outer-membrane porin (differing from one gonococcal por allele at only a single nucleotide site), and was clearly distinct from the porB genes of N. meningitidis. The isolate therefore appears to be a typical meningococcus, except that its porB gene has been replaced with the por gene from a gonococcus. 相似文献