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1.
1. Dab, Limanda limanda, exposed to nominal concentrations of 0 (control), 0.0032% (low) and 0.032% (high) sewage sludge in seawater for 12 weeks, were assessed for their immunological competence. 2. No effect upon total blood leucocyte and erythrocyte numbers was found, although significantly fewer thrombocytes were seen in the high-exposure group. 3. A decreased serum protein level was found in the high exposure group, but lysozyme and immunoglobulin levels showed non-significant differences between the groups. 4. Melano-macrophage centres were also affected in the high-exposure dab, which had increased numbers in the spleen and kidney. No effect upon spleen weights or oxygen free radical production by splenocytes was noted. However, oxygen free radical production by kidney leucocytes was inhibited in the low-exposure dab.  相似文献   

2.
  • 1.1. The aim of this work was to evaluate the relationships between free radical scavengers and lipid peroxidation in the common mussel Mytilus edulis.
  • 2.2. Mussels were exposed to compounds known for their ability to produce free radicals (carbon tetrachloride, CCl4) and reactive oxygen species via redox cycling (menadione), and the effects on digestive gland, gills and remaining tissues were studied.
  • 3.3. Lipid peroxidation parameters and the status of free radical scavengers (glutathione, vitamins A, E and C) were affected more by exposure to menadione than to CCl4.
  • 4.4. The observed changes in the free radical scavengers content are indicative of a role in detoxication of damaging reactive species.
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3.
  • 1.1. Seasonal acclimatization effects on oxygen consumption, body temperature, and body weight were evaluated in three different experimental groups of Dipodomys panamintinus.
  • 2.2. Body weights of wild field as well as captive animals housed in outdoor sand cages were maximum in winter and lowest in summer for both sexes.
  • 3.3. Mean oxygen consumption was maximum in winter and lowest during spring in both sexes of the wild field and captive exposed groups.
  • 4.4. Neither weight nor oxygen consumption of indoor control animals varied with the seasons.
  • 5.5. No significant differences in body temperatures were observed during either the fall or winter seasons.
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4.
  • 1.1. Total content of DNA and RNA in liver, kidney and spleen were measured in young and aged rats. At the same time the incorporation of [14C]thymidine, a DNA precursor, and [3H]uridine, an RNA precursor, were also determined.
  • 2.2. Changes in total organ DNA and RNA correlated with sexual maturation as did incorporation of precursors.
  • 3.3. Young animals have more DNA per organ relative to RNA. with kidney and spleen DNA showing a decrease between maturity and senescence.
  • 4.4. However, liver RNA increases with age. a change probably due to decreased catabolism of RNA since [3H]uridine uptake decreases.
  • 5.5. Liver polyploid differentiation, and [14C]thymidine and [3H]uridine uptake, are correlated.
  • 6.6. In kidney, incorporation of [3H]uridine is inversely related to [14C]thymidine incorporation.
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5.
  • 1.1. A brief review of development of ideas of the antioxidant activity of carnosine and related compounds is presented.
  • 2.2. An analysis of the behaviour of carnosine in different models of free radical chain reactions shows that carnosine is a potent hydrophylic antioxidant of a direct non-enzymatic action.
  • 3.3. It is characteristic of the higher activity of interaction with active hydroxyl radical.
  • 4.4. However the known biological effects of carnosine cannot be explained only by its anti-oxidant properties.
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6.
  • 1.1. We examined immobilization stress-induced antioxidant defense changes in rat plasma and observed the antioxidant effect of reduced glutathione (GSH) administration on these changes.
  • 2.2. Immobilization stress induced severe bleeding in the stomach and a significant increase in plasma levels of thiobarbituric acid receives substances (TBARS).
  • 3.3. Immobilization stress induced a significant decrease in plasma iron-binding, ironoxidizing protections and radical scavenging activity.
  • 4.4. Plasma levels of ascorbic acid, ascorbyl radical and superoxide dismutase activity remained unchanged following immobilization stress.
  • 5.5. Treatment with GSH showed a significant protective effect on stomach bleeding, on the increase in plasma TEARS, and on the decrease of iron-binding, iron-oxidizing protection and radical scavenging activity in plasma.
  • 6.6. These results suggest that immobilization stress induces generation of reactive oxygen species and decreases the endogenous antioxidant defenses, which can be attenuated by extracellular administration of antioxidant GSH.
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7.
  • 1.1. The cathepsin D was purified 1830-fold under mild conditions by a rapid procedure, based on two-step affinity chromatography.
  • 2.2. Its molecular weight, amino acid composition and substrate specificity were shown to display minor differences from materials of other origins.
  • 3.3. Inhibition with thiol compounds was found to be a specific phenomenon of the cathepsin D from the human spleen.
  • 4.4. Production of antiserum specific for purified cathepsin D was demonstrated by immunodiffusion test, an immunoadsorbent column and immunoblotting of the crude enzyme in SDS gel.
  • 5.5. In an immunocytochemical study, the antigenic sites for this enzyme were found to be localized in the reticuloendothelial system of the human spleen.
  • 6.6. The role of this enzyme in human spleen cell was discussed.
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8.
  • 1.1. Major lipid classes from cortical and medullary zones of normal and nephrosclerotic human kidneys have been isolated and the fatty acid composition of each determined.
  • 2.2. The nephrosclerotic tissue contained two times more total lipid than the normal kidney but, irrespective of kidney pathology, phospholipids were the major cortical lipids and neutral lipids were the predominant lipids in medullary zones.
  • 3.3. Human kidney contained large amounts of phosphatidylcholines, phosphatidylethanolamines and sphingomyelins and although these were slightly increased in the sclerotic kidney, anatomical differences in phospholipid content were not significant.
  • 4.4. Quantitative differences between the zones of normal kidney were found with triglycerides, diglycerides. free fatty acids and cholesterol; overall, the sclerotic tissue contained more triglycerides and small amounts of cholesterol esters with less significant regional differences.
  • 5.5. Palmitic, oleic and stearic acid were the major fatty acids of neutral lipids; these plus linoleic acid were prevalent in phospholipids.
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9.
  • 1.1. The oxygen consumption of crabs in normoxic and hypoxic (50% O2) seawater was measured directly after collection.
  • 2.2. The influences of size and lunar cycles were removed by scaling the data.
  • 3.3. Strong negative correlations between low individual levels of O2 consumption and the ability to compensate for hypoxia were apparent in Wicklow (subtidal) crabs.
  • 4.4. Compensation for hypoxia was much greater on the flood tide than on the ebb.
  • 5.5. Crabs from Roscoff (intertidal) had lower levels of compensation than those from Wicklow.
  • 6.6. Size, sex and condition had no apparent effect upon these relationships.
  • 7.7. Crabs acclimated to laboratory conditions have not shown this tidal variation in compensation for hypoxia.
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10.
  • 1.1. Isolated mitochondria from rat liver were incubated in the presence of [U-14C]palmitate, ATP, CoA, carnitine, EGTA (ethylene glycol bis (β-aminoethyl ether) N,N′-tetraacetic acid) and varying amounts of calcium.
  • 2.2. When a KCl-based incubation medium was used, the oxidation of palmitate was inhibited when the concentration of free calcium was increased from about 0.1–10μM.
  • 3.3. When a sucrose-based incubation medium was used, the basal rate of palmitate oxidation was about half of that observed with the KCl-medium and calcium had a stimulatory effect.
  • 4.4. With the KCl-medium the rate of oxygen consumption was inhibited by calcium with α-ketoglutarate as well as palmitate as the respiratory substrate.
  • 5.5. No inhibitory effect of calcium was observed with succinate or β-hydroxybutyrate.
  • 6.6. With the KCl-medium and with α-ketoglutarate as the respiratory substrate, state 3 respiration but not state 4 respiration was inhibited by calcium.
  • 7.7. When the sucrose-medium was used, state 3 respiration was first inhibited by calcium, but this inhibition was gradually relieved and the respiratory rate finally became higher than it was before calcium addition.
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11.
  • 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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12.
  • 1.1. S-d-Lactoylglutathione accumulates in human platelets activated by agonists. Among the tested inducers thrombin is the most active.
  • 2.2. The effect is dose and time-dependent. S-d-Lactoylglutathione, corresponding to depleted pool of reduced glutathione, can also be detected in platelets incubated with exogenous methylglyoxal.
  • 3.3. A further significant increase was observed in platelets stimulated with trombin in the presence of methylglyoxal.
  • 4.4. No change in glyoxalase activities upon platelet stimulation with thrombin was shown.
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13.
  • 1.1. The hemoglobins of Leporinus friderici were separated by liquid chromatography on DEAE-Sepharose in order to isolate the two major electrophoretic components.
  • 2.2. The chromatographic fraction I (electrophoretically slow anodic) showed no Bohr effect and no nucleoside triphosphate modulation.
  • 3.3. The chromatographic fraction III (electrophoretically fast anodic) showed a normal Bohr effect and addition of nucleoside triphosphate decreased oxygen affinity but did not alter the Bohr effect.
  • 4.4. The whole hemolysate showed a normal Bohr effect and phosphate modulation altered both Bohr effect and oxygen affinity.
  • 5.5. No or little difference between the effect of adenosine or guanosine triphosphates on hemoglobin function was observed.
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14.
  • 1.1. In the rat chronic metabolic acidosis increases the net synthesis of 17 renal cortex proteins by amounts ranging from 1.5 to 4.5-fold.
  • 2.2. These proteins have molecular weights between 13,000 and 42,000 and isoelectric points between approximately 5.5 and 7.0.
  • 3.3. No new proteins not also present in normal animals are detected in renal cortex samples from acidotic animals.
  • 4.4. Three proteins undergo substantial reductions in their net synthetic rates in chronic metabolic acidosis.
  • 5.5. On the basis of their physical properties and similar alterations in net synthetic rate in acidosis some of these proteins appear to be closely related and may be coordinately expressed in the rat kidney.
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15.
  • 1.1. Resting oxygen consumption at 10°C did not change from normoxia (150 mm Hg) down to an oxygen tension of 55 mm Hg for the flounder, Platichtys flesus.
  • 2.2. Flounders exposed to hypoxia showed increased levels of blood glucose and lactate, dependent on the degree of hypoxia.
  • 3.3. Due to hypoxia glycogen was depleted in the liver and swimming muscle but in the heart there was no significant change.
  • 4.4. Liver glucose increased after 7 hr of hypoxia. Heart and muscle glucose did not change but the absolute glucose concentration in the heart was five times higher than in the muscle.
  • 5.5. There is a transient accumulation of lactate in heart, liver and kidney after 7 hr of hypoxia while lactate accumulation in the swimming muscle is significant only after 21 hr of hypoxia.
  • 6.6. Succinate only accumulated in the liver while alanine accumulated in muscle, heart and liver.
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16.
Experimentally induced terrestrial dormancy resulted in reduced rates of oxygen consumption and carbon dioxide release by the turtle, Kinosternon flavescens.
  • 1.2. An unusually low respiratory quotient for dormant turtles indicates retention of carbon dioxide.
  • 2.3. Sharply elevated levels of oxygen consumption upon emergence from dormancy suggest payment of an oxygen debt and support previous suspicion of increased anaerobic metabolism.
  • 3.4. Most of the weight lost by dormant turtles is attributed to dehydration rather than metabolism.
  • 4.5. Suppressed gas exchange apparently reduces water loss from the respiratory tract, an adjustment which may be essential in avoiding severe dehydration.
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17.
  • 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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18.
  • 1.1. A variety of haematological parameters were determined in adult Dasyurus viverrinus.
  • 2.2. Haemoglobin and red cell counts were high with a very low mean cell volume.
  • 3.3. Basophils are absent but the eosinophils contain small numbers of basophilic granules which may indicate a dual role for this cell.
  • 4.4. “Ring Form” leucocytes are present.
  • 5.5. Three types of red cell picture could be identified, some animals showing large numbers of spherocytes, spicule cells, and inclusion bodies.
  • 6.6. These cells resemble those found in some inherited human haemolytic anaemias but there was no evidence of haemolysis in the animals.
  • 7.7. An alkali resistant haemoglobin component is present.
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19.
  • 1.1. Intramammary colchicine infusion into goats at parturition reduced milk yield by 20% during the 30 day experimental period.
  • 2.2. During the first week of lactation, milk composition from colchicine-treated udder halves had elevated somatic cell numbers, serum albumin concentration and pH, while citrate concentration was lower in comparison to uninfused glands.
  • 3.3. Levels of lactose from both infused and uninfused udder halves were normal during the first week of lactation.
  • 4.4. No differences were observed in degree of alveolar development in tissue samples collected prior to treatment.
  • 5.5. Light and electron microscopy suggested that colchicine-treated udder halves consisted predominantly of undifferentiated mammary secretory cells, while uninfused udder halves appeared more cytologically differentiated.
  • 6.6. Results demonstrated that intramammary colchicine infusion at parturition temporarily altered milk composition and inhibited mammary cellular differentiation.
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20.
  • 1.1. The oxygen consumption of red and green Carcinus in normoxic and hypoxic sea water was determined, using an oxygen electrode in a sealed respirometer.
  • 2.2. The red crabs had significantly higher “excited” oxygen uptake rates and a lower ability to compensate for hypoxia than the green crabs.
  • 3.3. Red Carcinus display an emersion response to declining oxygen at lower oxygen tensions than the green crabs.
  • 4.4. Mortality of red crabs exposed to prolonged anoxia was much greater.
  • 5.5. The relationship of these findings to the zonation of the two colour forms on the shore is discussed.
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