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1.
  • 1.1. The double isotope ratios and specific radioactivities of individual lipid fractions in major tissues of mice have been determined before and after ethanol ingestion.
  • 2.2. Several significant alterations in these ratios were caused by this treatment, with marked increases in most liver lipids and diverse responses in other tissues.
  • 3.3. These data establish that ethanol ingestion causes widespread perturbations in tissue lipid metabolism, with the main emphasis being directed towards an increase in the rate of synthesis of the liver lipid classes.
  • 4.4. The data also provides indications of an increase in the peroxisomal oxidation of fatty acids following ethanol ingestion, with the different distribution of ethanol metabolizing systems giving rise to individual metabolic responses in the separate tissues.
  • 5.5. These results have been discussed in relation to the eatablished involvements of lipid metabolism and tissue interactions in the whole animal.
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2.
  • 1.1. The carcinoma showed higher enzyme activities than the normal mammary tissue.
  • 2.2. The ratios of glutamate dehydrogenase, glutathione reductase and catalase to lactate dehydrogenase were lower in carcinomas than in normal tissues. Similarly, the ratios of glutamate dehydrogenase, glutathione reductase and catalase to glucose-6-phosphate dehydrogenase were also significantly lower in carcinomas.
  • 3.3. There were no significant differences in enzyme activities between stages I and II of disease, however in the metastatic tissues, there were significant differences between stages I and II.
  • 4.4. SH groups were higher in the tissues of cancer patients than in normal tissues. The levels of thiols groups were higher in carcinomas at stage III of disease.
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3.
  • 1.1. The subcellular distribution of nine transition metals (plus four additional elements) was measured in the kidney tissue of the quahog, Mercenaria mercenaria.
  • 2.2. Elemental analyses of the subcellular fractions indicated three main patterns of metal distribution within kidney cells.
  • 3.3. Barium, iron, manganese and lead were associated primarily with kidney granules.
  • 4.4. Cadmium, copper, potassium and magnesium were found mainly in the cytosolic fraction.
  • 5.5. Calcium, phosphorus and zinc were found in all isolated fractions, probably reflecting the important roles that these elements play in bivalve metabolism.
  • 6.6. The organelle composition of the isolated subcellular fractions was determined using marker enzyme assays and microscopic techniques.
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4.
  • 1.1. Copper deficiency in rats results in a 2-fold increase in the level of lipid hydroperoxides in liver mitochondria and microsomes.
  • 2.2. The specific activity of cupro-zinc Superoxide dismutase decreases up to 30% while that of the mangano-enzyme is not changed.
  • 3.3. Glutathione peroxidase activity as well as catalase activity are suppressed in both cytosol and mitochondrial fractions from copper-deficient rat liver.
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5.
  • 1.1. Lipid concentration in adductor muscle ranged from 2–68, in visceral mass from 5–28, in mantle and gill from 5–20 and in heart from 27.8–79 mg/g wet tissue. Particulate matter lipids varied from 1.0–2.6 mg/1 of estuarine water.
  • 2.2. Neutral and polar lipids ranged from 25–38% of the total lipids in the oyster tissue and from 62–75% of the estuarine particulate organic matter.
  • 3.3. Seasonal maxima of lipid concentrations varied among oyster tissues. Peak particulate lipids occurred in November.
  • 4.4. It is proposed that seasonal variation in oyster lipids was more related to reproductive cycles than to food lipid supply.
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6.
  • 1.1. Phospholipids of the freshwater sponge Euspongilla lacustris from the Volga river estuary were examined.
  • 2.2. The freshwater sponges belonging to the family Spongillidae were shown to contain demospongic fatty acids.
  • 3.3. Composition of fatty acids in phospho-, glyco- and neutral lipid fractions was studied.
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7.
  • 1.1. Accumulation and distribution of dietary Se in relation to mortality was investigated in adult house flies.
  • 2.2. The midgut preferentially accumulated Se and thereby limited toxicity.
  • 3.3. Midgut Se concentrations were from 6- to 107-fold higher than in carcass, and from 15 to 71% of the total Se was associated with midgut.
  • 4.4. When dietary levels of Se were raised the midgut saturated at 15 μg Se/g tissue, followed by a rise in carcass levels to greater than 0.5 μg Se/g tissue and increased mortality.
  • 5.5. Se levels in lysosomal fractions were from 3- to 50-fold higher than in other subcellular fractions, suggesting that Se is sequestered in lysosomes.
  • 6.6. Se added to drinking water was toxic at 4–8 ppm.
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8.
  • 1.1. An affinity chromatography technique for the determination of turnover parameters has been applied to the study of carbonic anhydrase in a variety of mouse tissues.
  • 2.2. The methodology has allowed the establishment of the relative turnover characteristics in these tissues, and the evaluation of the half lives and degradation rate constants.
  • 3.3. Considerable variation was evident between the individual tissues, with synthesis being indicated as most rapid in intestine while degradation was highest in liver.
  • 4.4. These data have been discussed in relation to available comparisons in the literature, and the known physiological correlations of carbonic anhydrase in these tissues.
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9.
  • 1.1. Coelomic fluid of the earthworm, Lumbricus terrestris, contains lipid agglutinins that are primarily glycolipids. They are present in fluid from both immunized (induced) and unimmunized (naturally occurring) worms.
  • 2.2. Lumbricus agglutinins partially purified by Folch extraction followed by silicic acid chromatography, were present in all fractions but in highest concentration in acetone and methanol fractions.
  • 3.3. Immunodetection revealed agglutinin activity in acetone and methanol fractions, but not in the chloroform fraction.
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10.
  • 1.1. The organic composition of the body tissues of eight species of deep-sea aspidochirotid holothurian, collected between 500 and 4100m depth in the NE Atlantic Ocean, was obtained by the biochemical analysis of protein, lipid, carbohydrate and % ash.
  • 2.2. The major organic class was protein with soluble lipid the major soluble fraction in the ovary. Carbohydrate values were consistently low.
  • 3.3. The calorific value was significantly higher in the ovary than in the other tissues.
  • 4.4. The total body calorific content for two selected species, Benthothuria funebris and Mesothuria lactea, was 25.62 and 26.24J/mg ash-free dry weight (AFDW).
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11.
  • 1.1. Arteriovenous difference studies across the lactating rabbit mammary gland for glucose, acetate, triacylglycerol and non-esterified fatty acids during initiated involution are reported.
  • 2.2. A significant reduction in substrate utilisation is paralleled by a decrease in the activities of fatty acid synthetase, acetyl CoA synthetase, citrate synthase and glutamate dehydrogenase in biopsy samples taken from the gland.
  • 3.3. Results from the analysis of lipid fractions within the gland during this period are discussed in relation to lipid resorption.
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12.
Analyses by mass spectrometry of carbon/oxygen isotope compositions of lapilli and sagittal otoliths in the catadromous New Zealand mullet Mugil cephalus permit us to draw the following conclusions:
  • 1.1. Information on the type of aquatic environment a larval fish has experienced can be obtained from otoliths of the adult in two ways: drilled cores along the long axis of the sagitta can be analysed sequentially for carbon/oxygen isotope composition.
  • 2.2. The oldest isotope ratios, representing the time when the first aragonite was laid down, are closest to the centre, while material nearer to the edges of the earstone reflects carbon/oxygen isotope values of the environment the fish had experienced at the time of capture.
  • 3.3. The second approach involves the lapilli. These otoliths are universally smaller than the sagittae in adult fish, but at hatching the two are of equal size in many species of fish, including the mullet.
  • 4.4. Consequently, the lapillus carbon/oxygen isotope ratio closely resembles that of the larval environment (in our case, the estuarine waters of New Zealand's North Island), whereas averaged carbon/oxygen isotope ratios of the sagittae more closely agree with those of river water.
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13.
  • 1.1. Longitudinally split or completely regenerated branch tips from Leplogorgia virgulata show no differences in calcium uptake between control and ouabain treatments. This indicates that there is no ouabain sensitive Na+, K+-ATPase involved in calcium uptake.
  • 2.2. The tissue fractions of both regenerated and split branch tips show, at certain times, higher calcium uptake than control fractions. In the spicule fractions of these tips calcium uptake decreases in vandate treated specimens.
  • 3.3. Pulse-chase experiments show an initial rapid release of calcium from the tips into surrounding seawater.
  • 4.4. The results may suggest the presence of outwardly directed calcium pumps on the basal/lateral and apical plasma membranes of the epithelial cells. Outwardly directed calcium pumps may also be envisaged on the cell membranes of scleroblasts. In addition, pumps may move calcium into specific organelles of the scleroblasts en route to the spicule forming vacuoles.
  • 5.5. These pumps are likely to be Ca2+-ATPase.
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14.
  • 1.1. Analysis of the total lipid content (TL), components of the neutral lipid fraction (NLF), phospholipid fraction (PLF), recordings of electrical potential differences and diffusional permeability were carried out in the skin of the aquatic frog Rana cyanophlyctis subjected to in vivo salt stress (0.9 sodium chloride) for different durations (0, 1, 3 and 7 days).
  • 2.2. A general decrease of skin TL and of components of the NEE and PEE was observed.
  • 3.3. Stoichiometric ratios for skin PLF components under initial salt stress of different durations reveal an increase of the ratios of sphingomyelin and phosphatidyl choline after osmotic stress.
  • 4.4. The diffusional permeability of water increased following exposure to salt stress of I, 3 and 7 days duration.
  • 5.5. The transepithelial potential difference measured in vitro after a salt stress of 3 days was considerably higher than the controls.
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15.
  • 1.1. Exposure of human caeruloplasmin, an acute phase protein with antioxidant properties, to a mixture of xanthine/hypoxanthine and xanthine oxidase as a source of reactive oxygen intermediates decreased its ferroxidase and ascorbate oxidase activities and its ability to inhibit lipid peroxidation.
  • 2.2. Immunological reactivity was also altered.
  • 3.3. Exposure to hydrogen peroxide mimicked these effects.
  • 4.4. Exposure to low-intensity u.v. irradiation depressed caeruloplasmin's ability to inhibit iron-catalysed hyaluronic acid degradation.
  • 5.5. The results may explain the mechanism of the observed inactivation of caeruloplasmin within human rheumatoid synovial fluid.
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16.
  • 1.1. Eel were exposed to a sublethal concentration of lindane (0.335 ppm) for 6, 12, 24, 48, 72 and 96 hr.
  • 2.2. Concentrations of glycogen, glucose, lactate, pyruvate and lipids were determined in gill tissue after lindane exposure.
  • 3.3. Gill glycogen descreased and glucose levels increased at 6 hr of treatment, lactate and pyruvate concentration increased between 6 and 48 hr. Total lipid values decreased between 6 and 24 hr; thereafter, the levels increased up to 72 hr of exposure.
  • 4.4. Clear changes were found in all parameters tested in gill tissues. The observed effects of lindane on metabolism in fish are discussed in relation to acute stress syndrome.
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17.
  • 1.1. The effects of niacin deficiency on the relative turnover rates of proteins in various tissues of Japanese quail were investigated.
  • 2.2. The level of liver NAD was not affected by niacin deficiency whereas the level of pectoral muscle NAD was markedly reduced.
  • 3.3. In all dietary treatments the liver had the highest turnover rates of proteins, heart and brain had intermediate rates, and pectoral muscle had the lowest rates.
  • 4.4. Relative turnover rates of proteins in all tissues (particularly pectoral muscle) of the niacin deficient group were significantly higher than those of pair-fed control group, although there were no significant differences in turnover rate between pair-fed control and control groups.
  • 5.5. The high turnover rate of proteins in niacin deficiency was primarily attributed to enhanced degradation rate of proteins rather than enhanced synthesis rate of proteins.
  • 6.6. Optical density scanning (or densitometric) of water-soluble pectoral muscle proteins separated by isoelectric focusing revealed several additional minor protein bands between major protein bands in the niacin deficient group which were more pronounced in the acidic region of the gel.
  • 7.7. These results suggest that proteins with a low pI value in pectoral muscle of the niacin deficient animal are highly sensitive to protein degradation.
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18.
  • 1.1. Exogenous and endogenous tyrosine protein phosphorylation activities were examined in soluble and partieulate fractions from various normal tissues by using poly-[Glu-80Na, Tyr20] and a monoclonal antibody specific for phosphotyrosine.
  • 2.2. Phosphorylation of the exogenous substrate by the partieulate forms of TPKs was 2- to 10-fold higher than by soluble forms. The activities of partieulate and soluble enzymes decreased in the following order: spleen > (thymus = kidney) > testes ⩾ (pancreas = liver = brain) > heart.
  • 3.3. The level of endogenous phosphorylation in the tissues decreased respectively in the following order: thymus > brain ⩾ (pancreas = liver) > spleen > testes > kidney > heart for the partieulate fractions, and spleen > thymus > brain > pancreas ⩾ liver > testes > kidney > heart for the soluble fractions.
  • 4.4. A large number of phosphotyrosine-containing proteins were detected. In addition, several phosphotyrosine-containing proteins of similar molecular weight were found in different tissues and fractions.
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19.
  • 1.1. An apparent effect of insulin administration on enlargement of interscapular brown adipose tissue (BAT) was found in heat-exposed rats, but not in warm-adapted or cold-acclimated rats.
  • 2.2. BAT extracts from the heat-acclimated/insulin-treated (HI) rats notably increased the capillary growth in an in vitro angiogenesis model in which microvascular fragments and myofibroblastic (Mf) cells isolated from lipid tissues were grown in co-culture, although a direct effect of insulin was not high.
  • 3.3. BAT extracts from the HI rats stimulated the production of endothelial cell growth factor and collagen by Mf cells.
  • 4.4. It is probable that an increased angiogenic activity contributes to the capillary growth and tissue growth in BAT of HI rats.
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20.
  • 1.1. An improved, simple method for the evaluation of the protein catabolic rate in the tissues of the lamellibranch mollusc Mytilus galloprovincialis Lam. is presented.
  • 2.2. This procedure, which utilizes the technique of the decay curve of a labeled amino acid (14C-leucine) in the tissues, exploits the capacity of these organisms to rapidly take up soluble compounds from sea-water.
  • 3.3. When mussels are exposed to 14C-leucine in the sea-water, the labeled amino acid is rapidly accumulated into the cell proteins.
  • 4.4. A further addition of unlabeled leucine to the sea-water drastically decreases the specific activity of soluble amino acids into the cells, so that the reincorporation of the labeled leucine into the proteins becomes negligible, allowing a correct estimation of the degradation rate of the proteins.
  • 5.5. This procedure was utilized to evaluate the effect of phenanthrene on the rate of catabolism of cytosolic proteins in the digestive gland of mussels, and to study the relationship between the protein degradation rate and the activity of lysosomes, which play a well-established role in the catabolism of macromolecules.
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