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The usefulness of mutagenic treatment to enlarge isozymic variability of barley and the use of induced mutants for genetic analysis were evaluated. N-methyl-N-nitroso urea, sodium azide and gamma rays were employed as mutagenic agents. Electrophoretic assays of 3848 M₂ seedlings obtained by chemical mutagenic treatment of the spring barley cultivars Dema, Aramir, Bielik and 3100 M₂ seedlings obtained by physical mutagenic treatment of the cv. Dema revealed 70 isozymic mutants, which represent 30 separate mutants in 25 M₁ plants. Most of mutations (27) were induced by chemical mutagen at polymorphic esterase loci. The occurrence of induced mutants at monomorphic loci, Got2 and Lap2, made it possible to perform genetic analysis of those loci in barley including mapping respective genes within chromosomes.
Objective: Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are present in esophageal cancer cells. Moreover the total activity of ADH as well as the activity of class IV ADH isoenzyme is significantly higher in cancer tissue than in healthy mucosa. The activity of these enzymes in cancer cells is reflected in the sera and could thus be helpful for diagnostics of esophageal cancer. The aim of this study was to investigate a potential significance of ADH isoenzymes and ALDH as tumour markers of esophageal cancer. We defined diagnostic sensitivity, specificity, predictive value for positive and negative results, and receiver-operating characteristics (ROC) curve for tested enzymes. Methods: Serum samples were taken for routine biochemical investigation from 180 patients with esophageal cancer before treatment. Total ADH activity was measured by a photometric method with p-nitrosodimethylaniline as a substrate and ALDH activity by a fluorometric method with 6-methoxy-2-naphtaldehyde as a substrate. For the measurement of the activity of class I and II isoenzymes we employed the fluorometric methods, with class-specific fluorogenic substrates. The activity of class III alcohol dehydrogenase was measured by a photometric method with formaldehyde and class IV with m-nitrobenzaldehyde as a substrate. Results: There was a significant increase in the activity of class IV of ADH isoenzyme (7.65 mU/l vs 5.88 mU/l) and total ADH activity (1198 mU/l vs 848 mU/l) in the sera of esophageal cancer patients compared to the control. The diagnostic sensitivity for ADH IV was 72%, the specificity 76%, the positive and negative predictive values were 80% and 72% respectively. The area under the ROC curve for ADH IV was 0.65. Conclusion: The results suggest a potential significance of ADH IV as a marker of esophageal cancer.
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Proposal for a seed certification scheme

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Identity of reproductive material is essential in artificial forest regeneration. Legal regulations cannot guarantee proof of identity. State and private organizations have been cooperating to develop a seed certification scheme in forestry. Representative samples of forest reproductive material are taken at any production stage starting at the time of seed collection through to plant delivery as well as at time of changing ownership.The first sample at the time of seed harvest is used to determine the maximum potential yield of living germinants from the total collection. Furhtermore this and the other samples are tested randomly at a determined level of intensity or in case of doubt by Isozyme/DNA methods. Sampling techniques have been tested and described in a handbook. The biochemical-genetic tests are being standardized for all major commercial species. Forest reproductive material having been sampled in the described way will be certified "of provable identity" by a neutral agency. The Scheme will be open to anyone complying with the rules laid down. Larger forest owners have confirmed to preferably purchase "forest plants of provable identity".
The genetic diversity of re-established population of endangered species Allium angulosum L. was tested as a one part of rescue program. Founder individuals were picked in Chropyně - Záříčí area (North Moravia, Czech Republic) and new population was set in Protected Landscape Area Litovelské Pomoravi (North Moravia, Czech Republic). The task was whether the newly founded population was made by representative individuals to cover (include) the genetic variability of source (mother) population. Items were tested with variability assay of six isozyme systems (G-6-PDH, AAT, PGM, EST, ACP, PGI) using discontinuous polyacrylamide gel electrophoresis (PAGE). The method stated relatively sufficient level of variability on condition that new population would be raised to prevent genetic changes. Application of more tests checking the genetic diversity within population could be useful during reintroduction and management of endangered plant species.
Phospholipase C (PLC, EC 3.1.4.11) is the major starting point in the phosphatidylinositol pathway, which generates intracellular signals that regulate protein kinase C and intracellular calcium concentration. To date, three major types of phosphoinositide-specific PLC species named β, γ and δ, have been characterized. This article reviews recent studies on isozymes delta of PLC. Four such isozymes have been cloned and termed δ1-4. Their structural organization, regulation of activity and the interaction with membrane lipid are considered. The intracellular localization of delta isozymes and distribution in various tissues are presented. Attention is given to the pathological conditions in which an abnormal protein level of PLC d or its activity have been observed.
Anther culture is currently the most successful method for production of doubled haploid lines in flax. Recently, ovary culture was also described as a good source of doubled haploids. In this contribution we investigated the incorporation of enzyme polymorphism of acid phosphatase and peroxidase as molecular markers for the gametic origin of flax plants derived from anther and ovary cultures.
The quaternary structure of ten enzymes in hemiurid flukes of the genus Lecithochirium (Digenea, Hemiuridae) was inferred using allozyme electrophoresis. Allozyme variants with single-banded homozygotes and double-banded heterozygotes characteristic of monomeric enzymes were observed for aconitase, adenosine deaminase and phosphoglucomutase. The phenotypic variation (single-banded and triple-banded profiles) detected for glucose phosphate isomerase, isocitrate dehydrogenase, phosphogluconate dehydrogenase and malate dehydrogenase, suggest a dimeric structure for these enzymes. These results are consistent with structures already known for invertebrates, including parasitic helminths. Atypical heterozygote patterns were observed for fumarase and malic enzyme, both of which revealed monomeric profiles. Moreover, in the genus Lecithochirium, both monomeric and dimeric isozymes for hexokinase may be present. However, there are other possible explanations for the unusual triple-banded pattern detected for this enzyme. The results are discussed in the context of possible variations in subunit number of homologous enzymes within phylogenetically diverse groups such as parasitic helminths, and compared with those of previous studies using allozyme analysis.
The eukaryotic respiratory complexes carry out conserved reactions compared to their prokaryotic equivalents and contain conserved catalytic subunits. Despite these resemblances, eukaryotic complexes are more complex, containing additional subunits. Various lines of evidence suggest that these additional subunits protect against proteolysis, modulate catalytic activity and/or play a role in assembly. We suggest, however, that none of the present-day functions was the original driving force for their acquisition by the complex during evolution of the mitochondrial respiratory chain and that the incorporation was largely accidental, the small accessory subunits possibly being derived from imported presequences.
Barley (Hordeum vulgare) seedlings were exposed to flooding and activities of alcohol dehydrogenase (ADH) and their isoform profiles were determined. The flooding increased ADH activities in shoots and roots of the seedlings. By day 3, the activity increased to 4 and 3 times that of the initial level for the shoots and the roots, respectively. Only two bands of ADH isoform were found in the shoots and the roots of non-induced seedling, whereas five bands were identified in those of induced seedlings.
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