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1.
  • 1.1. The hepatic d-aspartate oxidase activity was found to be higher in female ddY and ICR mice than in their male counterparts. On the contrary, the free d-aspartate content in the liver was lower in female mice than in male mice, suggesting that d-aspartate is actually metabolized by d-aspartate oxidase in vivo.
  • 2.2. Oral administration of d-aspartate to the animals increased the hepatic d-aspartate oxidase activity 2–3 fold in both genders without any significant difference in the rate of the increase between the genders.
  • 3.3. Several peroxisomal enzyme activities other than d-aspartate oxidase examined were not affected by this treatment.
  • 4.4. Experiments in vitro suggested that the increase in the d-aspartate activity might be explained in part by stabilization of the enzyme by d-aspartate.
  • 5.5. The administration of clofibrate, a peroxisome proliferator, to male mice, increased the hepatic d-aspartate oxidase activity with a significant simultaneous decrease of d-aspartate content in the liver, in agreement with a possible role of the enzyme n vivo.
  • 6.6. On the other hand, the administration of clofibrate or dehydroepiandrosterone to female mice decreased the d-aspartate oxidase activity.
  • 7.7. The peroxisome proliferators were suggested to act to eliminate the gender difference of hepatic d-aspartate oxidase activity in mice.
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2.
  • 1.1. Seasonal variation in total lipids was examined in several body components of the turtle Sternotherus odoratus.
  • 2.2. Carcass fat stores in both sexes were depleted during winter. Additionally, a decline in carcass lipids was associated with increases in gonadal mass.
  • 3.3. Concentrations of liver lipids were maximal during August and minimal during winter.
  • 4.4. Males showed little seasonal change in plasma lipid levels, whereas females had seasonal peaks temporally associated with ovarian development and carcass fat storage.
  • 5.5. Ovarian concentrations of lipids were minimal after nesting and increased during fall.
  • 6.6. Results suggest that S. odoratus uses stored fats both for reproduction and maintenance during winter.
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3.
  • 1.1. The critical thermal minima (CTMin) and maxima (CTMax) were determined for field-acclimatized and laboratory-acclimated crayfish (Orconectes rusticus) throughout 1984.
  • 2.2. The CTMin and CTMax of field-acclimatized crayfish were seasonally adjusted by 9.7 C and 14.7 C respectively.
  • 3.3. Seasonal variation in both tolerance regimes persisted in crayfish acclimated in the laboratory at 5 and 25°C for one week; however, no diel variation existed in either the CTMin or CTMax of laboratory-acclimated crayfish.
  • 4.4. Integration of thermal acclimation of the CTMin and CTMax with seasonal conditioning may influence the functional capacities of this species when considered in relation to the seasonal ranges in stream temperature.
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4.
  • 1.1. The effect of myo-inositol on the ability of three species of nematodes to survive desiccation has been studied.
  • 2.2. Survival rates obtained from worms treated with an inositol bathing medium were compared with survival rates of worms treated with distilled or tapwater media.
  • 3.3. Highest survival rates were found in those nematodes that were placed in an inositol solution prior to desiccation.
  • 4.4. Tapwater facilitated higher revival rates than did distilled water in both D. dipsaci and D. myceliophagous.
  • 5.5. No such differences were found for A. tritici.
  • 6.6. The results are discussed in relation to the possible mechanisms of protection afforded by the different bathing media.
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5.
  • 1.1. High AMP deaminase activities were determined in the gill of one selachian, Scyliorhinus caniculus, and five teleosts, Anguilla anguilla, Cyprinus carpio, Salmo gairdneri, Perca fluviatilis and Esox lucius.
  • 2.2. The highest activity was generally found in skeletal white muscle, except in A. anguilla and S. caniculus.
  • 3.3. In s. caniculus a very high AMP deaminase activity was found in the blood where it was shown to be tightly regulated by inorganic phosphate.
  • 4.4. Seasonal variations were observed for AMP deaminase activity in gill and white muscle, but also for blood Hb and protein concentration in the three tissues examined.
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6.
  • 1.1. Blood proteins were studied by polyacrylamide disc gel electrophoresis in three species of prairie dogs, Cynomys gunnisoni, C. leucurus, and C. ludovicianus.
  • 2.2. The sera were separated into 13–15 fractions and the three species could be distinguished by both qualitative and quantitative differences in their serum patterns.
  • 3.3. Qualitatively, variations in the occurrence and number of slow albumin fractions are diagnostic at the species leel.
  • 4.4. Quantitative differences were most apparent in variation in the mobility of the major albumin fraction and the transferrin fraction.
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7.
  • 1.1. d-Alanine has been found in appreciable amounts in the eggs and embryos of the sea urchin Paracentrotus lividus.
  • 2.2. The content of d-alanine, expressed as pmol/egg or embryo, is 1.32 in the egg, 0.81 in the blastula, 0.54 in the gastrula and 0.60 in the pluteus.
  • 3.3. The percentage of d-alanine with respect to the total alanine (d + l) decreases during embryonic development.
  • 4.4. d-Amino acid oxidase, d-alanine transaminase and d-alanine racemase activities were found neither in eggs nor in embryos.
  • 5.5. Therefore, it does not appear likely that d-alanine is subject to oxidative metabolism.
  • 6.6. The decrease in this d-amino acid during development may be due to its utilization in the synthesis of a more complex molecule.
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8.
  • 1.1. An alkaline p-nitrophenylphosphate phosphatase has been purified 440-fold from extracts of Hatobacterium halobium.
  • 2.2. The enzyme has an apparent molecular weight of 24,000.
  • 3.3. A Km value for p-nitrophenylphosphate of 1.12mM has been found under optimal conditions.
  • 4.4. The enzyme is selectively activated and stabilized by Mn2+.
  • 5.5. It requires high salt concentrations for stability and maximum activity.
  • 6.6. It displays an unusual restricted substrate specificity of 25 phosphate esters tested, only phosphotyrosine and casein were hydrolysed besides p-nitrophenylphosphate.
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9.
  • 1.1. Muscle proteins from the chelae of six crayfish species and ten species of Uca were compared through disc electrophoresis (split gel technique).
  • 2.2. No intraspecies variation of the electrophoretic pattern was found.
  • 3.3. In interspecies comparisons all components (bands) were weighted individually and specified as ancestral or derived characters.
  • 4.4. In the crayfishes the phylogenetic trees constructed from electrophoretic and classical data were found to be congruent. In Uca some branches of either tree remained undefined. Each tree, however, helped complete the other one.
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10.
  • 1.1. Chemical structures were determined for the cuticular alkanes, alkenes, and certain of the alkadienes for 11 D. virilis group species.
  • 2.2. Male-specific hydrocarbons occurred in five species: these were 9-heneicosene in D. americana and D. novamexicana, 10-heneicosene in D. virilis, 5,13- and 5,15-pentacosadienes in D. kanekoi, and 9-pentacosene in one strain of D. lummei.
  • 3.3. Hydrocarbon profiles of newly emerged flies always differed from mature files.
  • 4.4. Relationships among the species, with respect to hydrocarbon profiles, were investigated by cluster analysis.
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11.
  • 1.1. The obligate methanol-utilising bacterium strain 4025 contains cytochromes b and c. Cytochrome a is never present.
  • 2.2. The soluble cytochrome c is similar to that from other methylotrophs in reacting (slowly) with carbon monoxide and it can be separated into two types, differing markedly in their isoelectric points.
  • 3.3. Some of the cytochrome b reacts rapidly with carbon monoxide and is thus the likely cytochrome oxidase (cytochrome o).
  • 4.4. The partially purified, NAD+-independent methanol dehydrogenase is similar to such enzymes from the other methanol-utilising bacteria in respect of its prosthetic group, dependence on ammonia or methylamine for activity and its wide substrate specificity.
  • 5.5. The fluorescence seen in colonies of this organism is probably due to a flavin derivative.
  • 6.6. This study of electron transport components does not shed any light on the unusually high copper requirement shown by this methylotroph.
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12.
  • 1.1. Glycollate oxidase has been purified to apparent homogeneity from Lemna minor L. grown on medium containing 7mM NO3.
  • 2.2. The enzyme is a highly basic protein with a sub-unit molecular weight of 42,000 and a holoprotein molecular weight of 250,000.
  • 3.3. The Lemna enzyme is a flavoprotein with a broad specificity for straight chain α-hydroxy acids, the preferred substrate being glycollate.
  • 4.4. It is also competitively inhibited by oxalate and phenyllactate.
  • 5.5. A comparison is drawn between the physical properties of glycollate oxidase from a number of higher plants and the degree of sub-unit aggregation in the resulting protomers.
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13.
  • 1.1. One adult male, eight pups (including two full term foetuses) and nine adult female harbour seals (Phoca vitulina) were analysed for indices of mixed function oxidase (MFO) activity.
  • 2.2. MFO activity was present in liver samples, but was at or below detection limits in samples of kidney, lung and pancreas.
  • 3.3. Hepatic ethoxyresorufin O-de-ethylase and benzo[a]pyrene hydroxylase activities were similar to those reported in other seals and in other mammals.
  • 4.4. Cytochromes P-450 and b5 concentrations were slightly lower than those observed in other mammals.
  • 5.5. MFO activities in newborn pups and foetuses were significantly lower than those in adult females.
  • 6.6. No qualitative differences in cytochrome P-450 isozyme distribution between foetal and adult samples could be discerned by electrophoresis.
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14.
  • 1.1. Pupae of Galleria mellonella and Pieris brassicae given an injection with live, non-pathogenic Enterobacter cloacae or abiotic foreign molecules induce an acquired immunity that corresponds with the synthesis of haemolymph proteins of antibacterial activity.
  • 2.2. This humoral defensive response which persists for several days, differs quantitatively between insect species and between the inducers used, although very different foreign bodies induced the same immune proteins in both lepidopteran insects.
  • 3.3. A stronger and longer lasting response was consistently noticed in pupae immunized with non-pathogenic bacterium than after sterile nutrient broth injections.
  • 4.4. A demonstrably elevated activity of haemolymph lysozyme and trace activity of cecropins found in pupae of Galleria treated with saline W, a salt solution physiological to moths, disappear soon after 36 hr from injection.
  • 5.5. In P. brassicae, however, sterile insect Ringer can give a varying, if present at all, immune response.
  • 6.6. A mechanical injury (sterile wounding of insect body) can occasionally induce a similar but much weaker response.
  • 7.7. The antibacterial activity was drastically reduced in Pieris or completely depressed in most pupae of Galleria when actinomycin D or cycloheximide was given at an early time post-immunization with E. cloacae.
  • 8.8. It is concluded that the de novo synthesis of ribonucleic acid and immune proteins is required for expression of antibacterial activity in pupal haemolymphs.
  • 9.9. The synthesis of an immune mRNA was completed about 7 hr after the injection of the immunizing bacteria.
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15.
  • 1.1. Response latencies, denned as the time between a d.c. electric shock and initiation of a fast-start (startle response) were measured for eight species of teleosts.
  • 2.2. Fast-start response latencies varied from 10 to 36 cm. Highest values were found for individuals of two solitary species, Etheostoma caeruleum and Cottus cognatus. Lowest values were found for Esox and Salwo gairdneri.
  • 3.3. Schooling in Perca flavescens, Lepomis macrochirus and Pimephales promelas significantly reduced fast-start response latencies by 7–16 msec. A 4 msec. reduction for Notropis cornutus was not significant.
  • 4.4. No reduction in fast-start response latency was found for Pimephales promelas given the illusion of a school or for individuals greater than 15 cm from a school.
  • 5.5. The observed variation in fast-start response latency would favour attack success of predators and escape success for schooled, but not solitary, presumptive prey.
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16.
  • 1.1. Crude extract of the whole digestive tract from the brown shrimp (P. californiensis) was investigated for digestive amylase activity.
  • 2.2. Considerable amylase activity was found at pH 6.5–8.0, with optimum pH at around 7.5.
  • 3.3. Optimum temperature was found between 30–40°C, similar to amylases from other crustaceans.
  • 4.4. Amylase activity was highly halotolerant, having 50% maximum activity at 3 M NaCl.
  • 5.5. Maximum amylase activity was found at 0.01 M NaCl.
  • 6.6. Amylase activity was partially inhibited by the divalent ions Hg2+, Zn2+, Cu2+ and Cr2+.
  • 7.7. Mg2+ and Ca2+ ions seemed to enhance amylase activity.
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17.
  • 1.1. Muscle esterase variation in Sceloporus jarrovi, sampled from 25 locations in southeastern Arizona, was investigated employing acrylamide gel electrophoresis.
  • 2.2. Three distinct esterase phenotypes were observed, presumably resulting from the expression of two gene loci, Est-1 and Est-2.
  • 3.3. Lizards sampled from all 25 locations were found to be monomorphic with respect to esterase encoded at Est-1. Further, lizards sampled from the Santa Rita and Pinaleno Mountains were also found to be monomorphic for esterases encoded at Est-2, whereas those sampled from the Chiricahua and Huachuca Mountains proved to be polymorphic.
  • 4.4. Characterization of the esterases utilizing eserine sulfate, diisopropylfluorophosphate, and sulfhydryl-group inhibitors revealed the EST-1 isozyme to be an arylesterase and the EST-2 isozymes to be carboxylesterases.
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18.
19.
  • 1.1. The activity of the lipogenic enzyme, acetyl-CoA carboxylase, was investigated in four insect species; Bombyx mori (Lepidoptera), Tenebrio molitor (Coleoptera), Glossina morsitans and Sarcophaga nodosa (Diptera).
  • 2.2. Acetyl-CoA carboxylase activity in larval, pupal and adult forms was compared with the saponifiable lipid mass at each stage of the life-cycle, and found to follow similar patterns except for Tenebrio molitor.
  • 3.3. The results are examined in relation to known metabolic requirements for each insect.
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20.
  • 1.1. O. edulis and C. gigas both exhibit a seasonal variation in AEC with minimum values in summer. Two factors, food and temperature, were examined to explain these low summer values.
  • 2.2. The AEC level varied with food level but a seasonal pattern was still observed. Two age groups of oysters were tested, giving a similar response.
  • 3.3. The effect of temperature on the seasonal variations in AEC was confirmed by a significant correlation between AEC and temperature. This relationship allows us to calculate an AEC standard that only retains the trophic information.
  • 4.4. Different trophic levels were identified in Marennes-Oléron Bay with AEC standard but growth rate was not related to them. So, AEC may inform on the carrying capacity of a given area but does not predict growth performances which will depend on other parameters.
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