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1.
  • 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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2.
  • 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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3.
  • 1.1. Subcellular distribution of (NA+, K+-ATPase and ouabain-insensitive ATPase (Mg2+-ATPase) are compared in branchial tissues of the euryhaline crab, Eriocheir sinensis, acclimated to fresh water.
  • 2.2. Both the anterior and posterior gills contain cAMP-dependent protein kinase and endogenous protein substrate for phosphorylation.
  • 3.3. Phosphorylation occurs in both “particulate” and “soluble” subcellular fractions but its stimulation by cAMP is restricted to the “soluble” fraction.
  • 4.4. serotonin (5-HT) and dopamine receptors are present only in the “light particulate” fraction isolated from the posterior gills.
  • 1.(a) Serotonin and dopamine have no effect on the phosphorylation observed in a subcellular fraction alone.
  • 2.(b) Activation of the phosphorylation by serotonin and dopamine is found when the soluble fraction (source of cAMP-dependent protein kinase) is added to the fraction P3 from the posterior gills.
  • 3.(c) No activation occurs with the fractions P3 as well as P1 or P2 (not shown) from anterior gills of fresh water crab.
  • 4.(d) Cyproheptadine, a serotonin receptor antagonist, inhibits the 5-HT dependent increase in phosphorylation.
  • 5.(e) The dopamine receptor antagonist, chlorpromazine, inhibits dopamine-stimulated phosphorylation.
  • 6.5. Ouabain mimics the effect of cyproheptadine on the serotonin-stimulated phosphorylation found in the posterior gills.
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4.
  • 1.1. An SDS-PAGE study of the qualitative and quantitative differences in protein bands from haemolymph and ovaries of Spilostethus pandurus females treated with JH or chemically allatectomized with precocene II, has been done.
  • 2.2. The SDS-PAGE study of haemolymph revealed the occurrence of three female-specific proteins. In the ovary appeared three protein fractions (A, Band C) with mol. wts similar to those from haemolymph.
  • 3.3. The three female-specific proteins from the haemolymph, and the ovary bands B,C and D were absent in the samples from PII-treated females.
  • 4.4. JH accelerates ovary growth and the relative amounts of bands B, C and D were in relation to the physiological stage of the considered ovaries.
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5.
  • 1.1. Cuticular hydrocarbons of two clones of Rhopalosiphum maidis, two of R. padi, one of R. insertum, and one of Schizaphis graminum were identified as n-alkanes, monomethylalkanes and dimethylalkanes.
  • 2.2. No qualitative differences in hydrocarbon content were apparent among the six aphid populations studied; however, hydrocarbon profiles were discriminatory.
  • 3.3. Discriminant analysis of the proportions of the cuticular hydrocarbons selected 29 hydrocarbon components that provided discrimination among populations except for the two R. padi clones which were indistinguishable.
  • 4.4. Scanning electron micrographs showed very clear differences in the cuticular surface patterns among the three Rhopalosiphum species.
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6.
  • 1.1. Patterns of osmoregulation were studied in three species of Swan river atherinids (Leptatherina presbyteroides, lower estuarine and marine; Craterocephalus mugiloides, mid estuarine; Leptatherina wallacei, upper estuarine) over a wide range of salinities.
  • 2.2. The plasma Na+ concentration was elevated with an increase in salinity.
  • 3.3. Haematocrit and body water content decreased with acclimation to higher salinity.
  • 4.4. All three species of atherinids osmotically regulated over a salinity range greater than that which these fish are reported to occur in.
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7.
  • 1.1. Components of the cell surface of Crithidia guilhermei, Crithidia deanei and Crithidia oncopelti were radioiodinated by the iodogen technique. The distribution of proteins in the detergent-poor (DPP) and detergent-enriched phase (DRP) were studied using a phase separation technique in Triton X-114 and one- and two-dimensional polyacrylamide gel electrophoresis in sodium dodecyl sulphate (1D and 2D SDS-PAGE).
  • 2.2. Significant differences were noted in the proteins present in the DRP when the three species were compared.
  • 3.3. Two major bands with mol. wt 28,000 and 56,000 and motility in the pH gradient of 7.4 and 6.3, respectively, were observed in C. guilhermei, but not discernible in C. deanei and C. oncopelti.
  • 4.4. One polypeptide with mol. wt 50,000 and p1 4.9 was identified in the DRP of C. deanei.
  • 5.5. A broad band with mol. wt 68,000–140,000 and pI 4.7–5.5 was clearly observed in the DRP of C. deanei and one or two polypeptides only present in the DPP were observed in the three Crithidia species analyzed.
  • 6.6. Our observations show that C. guilhermei has characteristic surface polypeptides not found in C. deanei and C. oncopelti.
  • 7.7. Our results, in association with those reported by others, show that the phase separation using Triton X-114 offers a simple approach to the separation and further analysis of a select group of proteins from the bulk of the cellular proteins.
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8.
  • 1.1. Hemoglobin, hematological parameters, intraerythrocytic phosphates and whole blood Bohr effect of Pterygoplichthys multiradiatus, from the Amazon river, were studied in three different conditions: in their natural environment, acclimated to normoxia and acclimated hypoxia conditions.
  • 2.2. Nine anodal hemoglobin fractions were detected on starch gel electrophoresis. No qualitative differences in the Hb electrophoretic patterns were detected in the three studied groups.
  • 3.3. Hematocrit, hemoglobin concentration, MCV, MCHC and MCH were different among studied conditions.
  • 4.4. GTP was almost absent in the blood of animals in natural conditions and acclimated to hypoxia, but was present at a concentration similar to ATP in normoxic acclimated animals.
  • 5.5. There is a tendency for higher Hb-O2 affinity for hypoxic acclimated/acclimatized animals.
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9.
  • 1.1. The ability to tolerate extracellular freezing as an adaptation for winter survival was tested in seven species of terrestrially-hibernating amphibians found in eastern Canada.
  • 2.2. All species had only moderate supercooling abilities, with whole animal supercooling points of −1.5 to −3°C.
  • 3.3. Two salamander species, Plethodon cinereus and Ambystoma laterale, and the toad, Bufo americamts, were freezing intolerant and were killed when frozen for 24 hr at temperatures just below their supercooling points. The major winter strategy of these animals appears to be behavioural avoidance of subzero temperatures.
  • 4.4. Four species of frogs Rana sylvatica, Hyla versicolor, Hyla crucifer and Pseudacris triseriata, survived extracellular freezing at moderate subzero temperatures (−2 to −4°C) for periods of time ranging up to 2 weeks.
  • 5.5. All four frog species accumulated low molecular weight carbohydrates as cryoprotectants, glycerol being the major cryoprotectant in adult H. versicolor, while immature adults of this species as well as the other three species all produced high levels of glucose as the cryoprotectant.
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10.
  • 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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11.
  • 1.1. Albumin purified from rhesus monkey (MSA) shows immunological cross-reactivity with human serum albumin (HSA) by RIA.
  • 2.2. The amino-terminal sequence of MSA shows a high degree of homology to HSA.
  • 3.3. Thirty minutes after injection of radioactive leucine directly into the portal vein, albumin was purified chemically from the liver, kidneys and serum.
  • 4.4. At this time, 15% of the label was incorporated into liver homogenate protein.
  • 5.5. A highly labelled immunoreactive albumin form was purified from liver to constant specific radioactivity and separated from tissue and serum albumin.
  • 6.6. The specific radioactivity of this proalbumin was 36-times higher than the specific radioactivity of albumin in liver tissue.
  • 7.7. These similarities to HSA suggest that this non human primate species can serve as a useful model of human albumin synthesis in vivo.
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12.
  • 1.1. Lipid and phospholipid compositions of endemic freshwater molluscs belonging to the class Gastropoda, Baicalia oviformus and Benedictia baicalensis, were studied.
  • 2.2. The fatty acids composition of total lipids, neutral, glyco- and phospholipid fraction was investigated by capillary gas chromatography-mass spectrometry.
  • 3.3. Ninety-five fatty acids were identified: 23 saturated (both iso- and anteiso-), 28 monoenoic, 14 dienoic and 30 polyenoic.
  • 4.4. High percentage of the two main acids, 18:4 and 18:4(n-3) in phospholipid and glycolipid fractions were identified.
  • 5.5. A number of unusual polyunsaturated fatty acids, such as 19:4, 18:5(n-3), 24:4(n-6), 24:5(n-6), 24:6(n-3), and furanoid acids, were found.
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13.
  • 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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14.
  • 1.1. Ion dependence and vanadium-induced inhibition on branchial sac ATPase in five species of ascidian Phlebobranchiata (vanadium-accumulating) and Stolidobranchiata (iron-accumulating) were studied.
  • 2.2. The ATPase was obtained from the microsomal fraction, which was prepared from each ascidian branchial sac.
  • 3.3. The ATPase was dependent on Mg2+ and activated by exogenous Na+ + K+.
  • 4.4. Ouabain inhibited the ATPase activity in vitro, 10 μM to 100 μM vanadate, in vitro, suppressed the (Na+, K+)-ATPase.
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15.
  • 1.1. Two major glycoprotein components were released in vitro by rat gastric mucosal cells after 4 hr incubation with radioisotopes: a high molecular weight fraction with the characteristics of a fucomucin and a low molecular weight fraction, the latter having a higher specific radioactivity than the former.
  • 2.2. Pulse chase experiments indicate that several low and high molecular weight glycoproteins are synthesized simultaneously with no precursor-product relationship between them.
  • 3.3. Common antigenic determinants, specific to the stomach were found on the 2 fractions, using immunofluorescence, both fractions appeared to be present in the same cells.
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16.
  • 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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17.
  • 1.1. Phenoloxidase activity and wound melanization was studied in five species of grasshoppers representing the subfamilies Melanoplinae and Oedipodinae.
  • 2.2. Most of the phenoloxidase activity was detected in the plasma fraction of grasshopper whole-body homogenates and supernatant fractions of the hemolymph. The species representing the Oedipodinae had 20–50% higher percentage of the total phenoloxidase activity associated with particulate matter from a whole-body homogenate when compared to the Melanoplinae.
  • 3.3. Phenoloxidase activity could not be detected in sclerotized cuticle of adult grasshoppers.
  • 4.4. The phenoloxidase existed as a zymogen which could be activated by chymotrypsin and inhibited by KCN and NaCN while EDTA showed no effect. It had optimum activity at 37°C and pH 7.3.
  • 5.5. These findings are discussed in relation to wound repair and immune responses to infection in grasshopper species.
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18.
  • 1.1. Observation of ventilation in immersed Pholis gunnellus showed a linear relationship between ventilatory rate and temperature between 8 and 20°C.
  • 2.2. At 13°C and after 30 min emersion, ventilatory rate was initially lower than prior to emersion, providing evidence of adequate uptake of O2 for standard metabolism during the emersion period.
  • 3.3. This species has a laterally elongate body form with reduced scales and extensive mucus secretion.
  • 4.4. During emersion, gaping behaviour probably exposes the gills and extensively vascularised oesophageal regions to air.
  • 5.5. These are considered to be morphological and behavioural adaptations by P. gunnellus, to aerial respiration in the intertidal habitats occupied by this species.
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19.
  • 1.Two eublepharid gecko species were tested for their thermal preferences in a thigmothermal gradient.
  • 2.Goniurosaurus kuroiwae kuroiwae from a humid subtropical Oriental forest selected a lower body temperature (Tp; average 16.6 °C) than Eublepharis macularius from an arid Palaearctic area (25.8 °C).
  • 3.Both the locations of animals along the gradient and the Tp were significantly more variable among G. k. kuroiwae than among E. macularius.
  • 4.There were no significant differences in Tp and in its variance between photophase and scotophase in either species.
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20.
  • 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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