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1.
  • 1.1. The activity of l-gulonolactone oxidase (EC 1.1.3.8) in livers of 49 species of eutherian mammals varied intraspecifically among individuals; coefficients of variation were 0.2 to 0.4 in many species.
  • 2.2. Differences observed in l-gulonolactone oxidase activity among strains of laboratory rats and domestic rabbits are probably genetically controlled.
  • 3.3. Pronounced sex differences in l-gulonolactone oxidase activity were found in some species, particularly in the genera Peromyscus, Reithrodontomys and Onychomys.
  • 4.4. Mormota monax exhibited seasonal variation in l-gulonolactone oxidase somewhat like that previously observed in Sylvilagus floridanus; no such seasonal variation was found in Sciurus carolinensis.
  • 5.5. Hibernation did not affect l-gulonolactone oxidase activity in Spermophilus tridecemlineatus.
  • 6.6. In four species of rodents, Microtus ochrogaster, Tylomys panamensis, Octodon degus and Sigmodon hispidus, l-gulonolactone oxidase activity was not affected by the level of dietary ascorbate.
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2.
  • 1.1. Resting spores, germinated spores, and mycelium of Penicillium roqueforti actively decarboxylate (β-ketolauric acid to 2-undecanone. The rate of 2-undecanone formation increases as resting spores germinate and activity is highest in mycelium.
  • 2.2. Glucose stimulated the formation of 2-undecanone by resting spores but had no effect on activity in mycelium.
  • 3.3. The enhanced methyl ketone production in spores is attributed to the progressive increase in activity of β-ketoacyl decarboxylase as spores germinated.
  • 4.4. Cell-free extracts obtained from mycelium contained heat stable and heat labile species of β-ketoacyl decarboxylase.
  • 5.5. Optimum pH for the conversion of β-ketolaurate to 2-undecanone was 6.5–7.0.
  • 6.6. Biphasic substrate saturation curves and a discontinuous slope in Arrhenius plot for β-ketoacyl decarboxylase suggested the existence of two species of ketoacyl decarboxylase in P. roqueforti.
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3.
  • 1.1. Soluble eye lens proteins of three species of Italian freshwater ictalurids were analyzed: Ictalurus sp., I. nebulosus marmoratus and I. punctatus.
  • 2.2. The electrophoretic and isoelectric focusing patterns were compared.
  • 3.3. Both techniques revealed species-specific patterns. I. sp. and I. nebulosus marmoratus exhibited very similar patterns, I. punctatus a quite distinct one.
  • 4.4. Some hypotheses warranting further investigation of the subject were proposed.
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4.
  • 1.1. Soluble eye lens proteins of fifteen different Sparidae species were analysed.
  • 2.2. Species-specific electrophoretic and isoelectric focusing patterns were found.
  • 3.3. Significant differences in the distribution of β and γ-crystallin protein components were noted for all species.
  • 4.4. These data suggest that the Sparidae family may be a heterogenenous taxonomic group encompassing considerable genetic diferences and with different evolutionary histories.
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5.
  • 1.1. An extraction medium was sought that would produce the highest quality electrophoretic patterns of proteins from bivalve molluscan adductor muscles.
  • 2.2. Cellulose acetate electrophoresis was conducted on adductor muscle proteins extracted with distilled water or various concentrations of saline, with and without dialysis, from three bivalve molluscan species: Pacific oysters, Crassostrea gigas; Japanese littleneck clams, Prototheca semidecussata; and Hawaiian mussels (Mahawele), Isognomon constellateum.
  • 3.3. The protein patterns obtained by electrophoresis revealed that muscle extracted and dialyzed in 0.030 g% NaCl solution produced superior patterns.
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6.
  • 1.1. The crystallin proteins of numerous species belonging to different classes of vertebrates have been studied.
  • 2.2. Species-specific crystallin patterns are revealed which unequivocally characterize the different species.
  • 3.3. A marked variability in the number and percentage of alpha-, beta- and gamma-crystallins were found in the various species.
  • 4.4. The gamma-crystallin family, with a meagre number of common bands, has proved to be most representative of the species. The beta-crystallins, with their greater number of common bands, have been best preserved throughout vertebrate evolution.
  • 5.5. From the similarity coefficient matrix a dendrogram is drawn up, a visual phylogenetic summary of the interrelationships between the vertebrates considered.
  • 6.6. In the Discussion, other aspects are considered, such as lens morphology, functionality, animal age, post-synthetic modifications and genetic factors.
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7.
  • 1.1. Tissue extracts of heart, kidney, gills and eye lens were electrophoretically examined for phosphoglucose mutase (PGM), superoxide dismutase (SOD), and glucose 6-phosphate dehydrogenase (G6PDH) activity in 32 species of teleostean fish.
  • 2.2. One locus of PGM, SOD and G6PDH was found in all groups of fish studied.
  • 3.3. The electrophoretic patterns of PGM and SOD can be considered as a good taxonomic criterion to differentiate Acanthopagrus latus, Lethrinus kallopterus, Otolithus ruber, Plectorhynchus schotaf and Synaptura orientalis from the remaining fish species studied.
  • 4.4. G6PDH and hexose 6-phosphate dehydrogenase (H6PDH) can be considered to be of a less taxonomic importance in differentiating the species of fish under consideration.
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8.
  • 1.1. High-Km, aldose reductase purified from dog kidney inner medulla was easily converted into aldose reductase by incubation in the neutral buffer solution.
  • 2.2. High-Km, aldose reductase was found to be in multiple forms, and was separated into three kinds of species designated as a-, b- and c-forms by HPLC.
  • 3.3. The a-form observed as a single peak by HPLC was assumed to be present in three forms (al-, a2- and a3-forms), one was aldose reductase (a 1-form) and the others were the precursors of aldose reductase (a2- and a3-form).
  • 4.4. The b-form was rapidly converted into the a3-form, followed slowly by the a2-form and finally into the a 1-form.
  • 5.5. The c-form was either directly converted into the al-form, or indirectly into the a2-form followed by the al-form.
  • 6.6. Four kinds of species (a2-, a3-, b- and c-forms) of high-Ap, aldose reductase were finally converted into aldose reductase (al-form).
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9.
  • 1.1. A lipoxygenase preparation was obtained from Thermoactinomyces vulgaris and was purified by affinity chromatography on a linoleyl aminoethyl sepharose column.
  • 2.2. Two active fractions were obtained.
  • 3.3. The fraction obtained by elution with 100 mM borate buffer pH 9.0 was used in the subsequent work.
  • 4.4. Th. vulgaris lipoxygenase oxidized linoleic acid into two products: 13-HPOD and 9-HPOD at a ratio of 44 to 56, respectively.
  • 5.5. The identification and characterization of the isomers was done by HPLC, I.R. and mass spectrometry.
  • 6.6. When arachidonic acid was used as substrate, 15-HPETE and 15-HETE were found to be the main enzymatic products.
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10.
  • 1.1. Localization of Zn (+ 65Zn) has been examined within twelve subcellular fractions (derived from discontinuous sucrose gradients) of preincubated T. tubifex.
  • 2.2. Zn was principally associated with the pellet (28% of total) and lowest density fraction (14%).
  • 3.3. Pellet ultrastructure is composed of chloragosomes and epicuticle. Pellet Zn is localized within chloragosomes, X-ray microanalysis showing chloragosomal Zn concentration to exceed epiculticular Zn by a factor of thirty.
  • 4.4. Biochemical and ultrastructural studies demonstrate that Zn is not appreciably bound to other cell constituents.
  • 5.5. Chloragosomal localization of internalized Zn indicates a capacity for detoxification.
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11.
  • 1.1. Analysis of the haemolymph composition of two species of New Zealand wetas gave the following data.
  • 2.2. Both species have a typical composition in terms of the inorganic fraction of the haemolymph, with Hemideina femorata having twice the amount of potassium found in H. maori.
  • 3.3. There were high concentrations of proline, glycine and alanine in both species of weta.
  • 4.4. Other organic fractions of the haemolymph of both species appear to be typical for the class Insecta. The significance of the results are discussed.
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12.
  • 1.1. Eye proteins of Pterolebias longipinnis have been analyzed by 2-dimensional isoelectric focusing SDS-polyacrylamide gel electrophoresis during aging from adolescence until normal death.
  • 2.2. The protein pattern on the gels changed gradually with progressing age.
  • 3.3. In senescent eyes, three protein spots appeared for a time and 36 disappeared from the pattern.
  • 4.4. The isoelectric points of the proteins in the presence of urea and the molecular weights in an unreducing buffer are presented.
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13.
  • 1.1. A survey was carried out to examine the usefulness of histopathology for the identification of toxic effects of environmental contaminants in fish.
  • 2.2. Two small fish species, Poecilia reticulata (guppy) and Oryzias latipes (medaka) were used, and two exposure periods (1 and 3 months) were chosen.
  • 3.3. The following compounds were studied: β-hexachlorocyclohexane, bis(tri-n-tributyltin)oxide, di-n-butyltindichloride, sodium bromide, methyl bromide, and methylmercury chloride.
  • 4.4. The following is concluded: histopathology provides useful data in characterizing toxic effects in fish; there is a slight advantage for Poecilia reticulata over Oryzias latipes; there is no advantage for 3 months exposure vs 1 month.
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14.
  • 1.1. Progressive ontogenetic changes in soluble nuclear eye lens proteins was demonstrated for the first time in a large species of shark.
  • 2.2. Comparison of fetal and post-natal sharks showed the shift in proteins to be gradual rather than statically related to life history events such as birth and sexual maturation.
  • 3.3. Studies considering the use of soluble nuclear eye lens proteins as a means of shark stock identification should at their onset consider ontogenetic changes as a possible source of protein variation.
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15.
  • 1.1. The utility of biochemical genetic methods of bird identification was investigated for some common species which create a hazard for commercial aviation in Ireland.
  • 2.2. Sixteen enzyme loci were assayed in eight species, using starch gel electrophoresis; three larids, three corvids and two columbids.
  • 3.3. Genera were distinguishable using all but two loci.
  • 4.4. Differences within genera were small, but all species except for the gulls Larus argentatus and L. marinus, could be identified using one or more loci.
  • 5.5. Arising from the success of the method using fresh specimens, a protocol for the electrophoretic identification of traumatized remains of strikes is suggested.
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16.
  • 1.1. Some aspects of the gas exchange system of a diving lizard, Physignathus lesuewii were studied.
  • 2.2. Breathing patterns were analysed.
  • 3.3. Breathing rate increases logarithmically with temperature and Q10 = 1.8. LogBR = −0.237 + 0.0256 T.
  • 4.4. Gas tensions in lung air and arterial and venous blood were measured. Arterial pH declines with increasing temperature.
  • 5.5. Temperature has a marked effect on oxygen affinity of the blood (ΔH = −10.1 kcal mol). A Bohr effect was also noted.
  • 6.6. CO2 equilibrium curves were drawn.
  • 7.7. The results are considered with a view to anticipating the efficiency of the gas exchange system of this species under conditions of variable temperature and during diving.
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17.
18.
  • 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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19.
  • 1.1. Patterns of fuel utilization in the thoracic muscles of three species of ants have been established.
  • 2.2. The thoracic muscles of Formica ulkei exhibit a typical Hymenopteran metabolic organization, relying exclusively upon carbohydrate oxidation for the provision of metabolic energy. This species feeds upon honeydew.
  • 3.3. Pogonomyrmex californicus, a granivorous ant, exhibits a metabolic organization unprecedented for a Hymenopteran species. Its thoracic energy metabolism is based upon lipid oxidation.
  • 4.4. Atta colombica, a fungus feeder, can metabolize both carbohydrate and fat, a versatility which is not typical of Hymenoptera.
  • 5.5. It is concluded that patterns of fuel utilization in insects are not determined by phylogenetic inertia, but are selected to accommodate the activity patterns, feeding ecology and dietary regime of the species.
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20.
  • 1.1. The capacity of five anuran Amphibians (Bufo viridis B. regularis, Rana ridibunda, Hyla arborea and Pelobates syriacus) to acclimate to NaCl and urea solutions was investigated.
  • 2.2. All species could be acclimated to relatively high concentrations of urea solutions, while only Bufo viridis and Hyla arborea could be acclimated to 500 mOsm/kg or higher NaCl solutions.
  • 3.3. The plasma urea concentration in B. viridis and H. arborea was elevated to levels over 140 mmol/1.
  • 4.4. The sum of plasma sodium and chloride concentrations did not increase over 400 mmol/l in any species.
  • 5.5. Urine osmolality, which was normally low, increased, but never exceeded the plasma osmolality.
  • 6.6. In the urea acclimation conditions, urine electrolytes diminished, similarly in all species in this study.
  • 7.7. It is concluded that anuran Amphibians can tolerate high plasma urea concentrations, but only those species which can elevate it, either through retention or net synthesis, can be acclimated to high salt solutions.
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