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1.
  • 1.1. The effect of sonication on reconstituted freeze-dried bovine and porcine blood was examined by analysis of particle size and by feeding to Glossina palpalis palpalis.
  • 2.2. Sonication reduced the particle size of both reconstituted blood products.
  • 3.3. Tsetse flies feeding on both sonicated blood products performed significantly better than flies feeding on non-sonicated blood products with respect to total pupae produced and fecundity, and for porcine blood, pupal weights were higher.
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2.
  • 1.1. Eggs of wild cod, and of farmed cod fed (a) a diet supplemented with astaxanthin and (b) a diet supplemented with both astaxanthin and canthaxanthin, were analysed with respect to carotenoids.
  • 2.2. The total carotenoid contents in eggs were 0.7 ppm for wild cod and 0.5 ppm for farmed cod.
  • 3.3. Cod, having white flesh, deposit ketocarotenoids in the eggs, preferably astaxanthin.
  • 4.4. Canthaxanthin can replace astaxanthin in the eggs, but astaxanthin appears to be deposited preferentially when both carotenoids are present in the diet.
  • 5.5. The isomer distribution of (3S, 3′S):(3R, 3′S, meso):(3R, 3′R) astaxanthin in the eggs reflected the isomer composition of the diet.
  • 6.6. Echinenone, 4′-hydroxyechinenone, adonixanthin and zeaxanthin encountered in cod eggs may represent reductive metabolites of canthaxanthin and astaxanthin.
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3.
  • 1.1. The sialic acid content of newborn calf serum (4.8 μmol/ml) is approx. 3-fold higher than that of mature animals (1.4 μmol/ml) and decreases to 2.4 μmol/ml at 20 days of age. Colostrum-fed and colostrum-deprived calves have similar levels of sialic acid from birth to 14 days of age.
  • 2.2. The high level of sialic acid in newborn calf serum is due predominantly to N-acetylneuraminic acid, since this sialic acid accounts for 93% of the total and since <5% of the sialic acid is O-acetylated.
  • 3.3. Comparison of day 0 and day 20 serum by gel filtration and by SDS polyacrylamide gel electrophoresis demonstrates that the increase in sialic acid is associated with increased production and/or sialylation of components with MW of 45–60 kDa.
  • 4.4. A high percentage (64%) of the sialic acid in newborn calf serum is detected with the lipid-linked sialic acid assay, relative to 20 day old (25%) or mature (18%) animals.
  • 5.5. This indicates that the glycoproteins of newborn calf serum are more efficiently extracted under the conditions of this assay than glycoproteins of mature serum.
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4.
  • 1.1. Amino acid sequences of bovine and porcine band 3, an erythrocyte anion transporter, were determined.
  • 2.2. The sequence of bovine band 3 was positioned to residues 519–599 (the numbering is based on human band 3), in which probably 6 residues were unidentified.
  • 3.3. Binding site of DIDS (4,4'-diisothiocyanostilbene-2,2'-disulfonate), a potent anion transport inhibitor, was identified as Lys-539 in the bovine case.
  • 4.4. A loop (residues 551–567), which provides exofacial proteolytic cleavage sites, contains only 53% homology between human and bovine, whereas the residues flanking it on either side are >84% homologous.
  • 5.5. Furthermore, the loop of porcine band 3 was indicated to consist of a 6 or 7-residues short peptide as compared with those of other species.
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5.
  • 1.1. Crossbred Yorkshire (Yorkshire × Landrace) pigs were fed butter oil, cream, low erucic acid rapeseed oil, sunflower oil and partially hydrogenated sunflower oil in amounts representing 30% of energy for periods of up to 13 weeks.
  • 2.2. After 13 wk of feeding serum total cholesterol levels of pigs fed milk fat were significantly higher than of pigs fed vegetable oils.
  • 3.3. The difference in cholesterol was mainly due to an increase in the density range of 1.063–1.125 g/ml containing pig LDL2 and some HDL.
  • 4.4. A shift towards smaller LDL particle size was apparent in pigs fed milk fat.
  • 5.5. The effects of dietary trans fatty acids did not differ from cis polyunsaturated or monounsaturated fatty acids.
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6.
  • 1.1. Comparative studies of EGF, TGF-α, and TGF-βl action on the synthesis of DNA and cellular proteins in rat L6 myogenic cells and fetal bovine myoblasts demonstrated considerable differences between particular growth factors, dependent on dose and target cells.
  • 2.2. Among examined growth factors only EGF exerted mitostimulatory action, more pronounced at lower concentrations. EGF, progressively with dose, stimulated protein synthesis much more effectively in fetal bovine myoblasts than in L6 cells.
  • 3.3. The dynamics of stimulation of protein synthesis by TGF-α was greater than by EGF in both examined types of cell cultures.
  • 4.4. The maximal response of fetal bovine myoblasts to TGF-α in a concentration of 100 ng/ml reached 370%, whereas EGF in a 10 times higher concentration stimulated protein synthesis only to 123% of control.
  • 5.5. In contrast to EGF, TGF-α significantly inhibits DNA synthesis. Inhibition of the mitogenic response with simultaneous stimulation of protein synthesis by TGF-α may indicate changes toward cell differentiation.
  • 6.6. TGF-β 1 in smallest concentration inhibits both DNA and protein synthesis. The suppressive action of TGF-β 1 was more distinct in fetal bovine myoblasts than in the L6 cell line.
  • 7.7. Increasing concentrations of TGF-β l diminished its inhibitory effect, even leading to stimulation of protein synthesis at higher doses in L6 myoblasts.
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7.
  • 1.1. High performance liquid chromatography (HPLC) was used to determine β-carotene and retinol in cow serum.
  • 2.2. Two groups of state and private farm cows (Groups 1 and 2) were used to assess seasonal variation when different food sources were fed to cows on serum β -carotene and retinol concentrations.
  • 3.3. Mean serum concentrations of β-carotene and retinol from October to April in both Groups 1 and 2 cows were lower (P < 0.05) than in the other months when the cows were fed various combination of maize silage, alfalfa and carrot residues and grass hay, respectively.
  • 4.4. Mean serum β-carotene and retinol concentrations in June and July were higher (P < 0.05) than in other months when the cows were in pasture.
  • 5.5. Mean serum β-carotene and retinol concentrations in May, August and September were lower (P < 0.05) than in June and July and higher (P < 0.05) than in other months when a lesser amount of green pasture was available to the cows.
  • 6.6. There was a seasonal variation (P < 0.05) in serum β -carotene and retinol concentrations. When the carotene intake is very high, conversion of β -carotene to retinol decreases. Mean monthly serum β -carotene and retinol concentrations showed that combination of alfalfa hay and maize silage, and grass hay and carrot residues can maintain adequate serum β-carotene and retinol concentrations during the dry season.
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8.
 
  • 1.The levels of water, Na, K, Ca and Mg in blood serum, brain and kidney and aldosterone level in blood of Naja haje haje were studied during the different phases of the annual cycle.
  • 2.The water content in the tissues studied displayed only minor changes as the animals passed from one phase to the other.
  • 3.A significant increase in Na was recorded in the brain during the different phases indicating a depressed sodium pump, whereas the blood Na level showed a significant decrease during hibernation.
  • 4.K increased in blood serum, brain and kidney during hibernation, while a nonsignificant decrease was found in blood serum during arousal. The brain may act as a potassium reservoir.
  • 5.An increase in Ca and Mg concentration was recorded in blood serum, brain and kidney during prehibernation and hibernation. The data suggested a homeostatic function in the transport and metabolism of these cations.
  • 6.Aldosterone exhibited a highly significant decrease especially during hibernation. The aldosterone regulation of ionic composition is discussed.
  • 7.Na/K and Ca/Mg ratios in the brain may explain the decreased excitability during winter torpor.
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9.
  • 1.Total lipids, free fatty acids, triglycerides, phospholipids and total cholesterol in blood serum, liver, brain, cardiac and skeletal muscles of Naja haje haje were determined during the different phases of the hibernation cycle.
  • 2.A sharp decrease in the level of total lipids of blood serum and all tissues occurred during hibernation. Upon arousal, lipogenesis is commonly restored.
  • 3.Elevated concentrations of serum free fatty acids predominated in pre-hibernation and hibernation periods, while the tissues recorded highly significant declines during hibernation.
  • 4.Occurrence of marked decreases in triglycerides contents of serum and tissues except the cardiac muscles in the hibernation and arousal phases.
  • 5.Sharp increases in the phospholipid contents of blood and the selected tissues were recorded during hibernation. The level declined in both liver and cardiac muscles in arousing animals.
  • 6.Total cholesterol level was lowered in blood during hibernation. The cardiac muscles showed a highly significant decrease while liver, brain and skeletal muscles showed elevations in the same phase.
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10.
  • 1.1. α-Difluoromethylornithine, an irreversible inhibitor of ornithine decarboxylase significantly abolished stimulation of protein synthesis evoked by EGF, TGF-α or -β 1 in L6 and fetal bovine myoblasts.
  • 2.2. The participation of polyamines in early events evoked by growth factors was shown by a significant stimulation of ornithine decarboxylase and Sdenosylmethionine decarboxylase activity as well as increased concentration of spermidine and spermine in L6 cells exposed to TGF-α and EGF.
  • 3.3. TGF-β 1 at a high concentration (1 ng/ml) increased protein synthesis in L6 myoblasts but inhibited it in fetal bovine myoblasts. Metabolic effects of TGF-β 1 in L6 cells was associated with an enhancement of decarboxylase activities, however there were no significant changes in cellular polyamine concentrations. Presented data suggest that polyamines are involved in the signal transduction pathway of EGF, TGF-α, and -β 1 in L6 and fetal bovine myoblasts.
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11.
  • 1.1. The present study was undertaken in order to define the distribution of canthaxanthin between the lipoprotein fractions in serum of immature rainbow trout fed a diet supplemented with synthetic canthaxanthin (80 mg/kg).
  • 2.2. Lipoproteins were separated by density-gradient ultracentrifugation.
  • 3.3. Canthaxanthin was found in all lipoprotein fractions, in different amounts according to the density of the lipoprotein fraction: VLDL, 13.9%; LDL, 15.2% or LDL, 29.1% since the density of the first fraction was 1.006 g/ml; HDL, 60.4% and VHDL, 10.5%.
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12.
  • 1.1. Growing male kittens were fed an 18% casein diet supplemented with 2, 3, or 4% l-methionine (MET) for 6 weeks.
  • 2.2. Free MET concentration in liver increased 30-fold and cystathionine two- to three-fold; the activity of adenosyl-MET transferase and cystathionase also increased but remained lower than previously found in rats.
  • 3.3. Taurine concentration in liver decreased in cats fed excess MET and appeared to depend on taurine intake.
  • 4.4. Alanine aminotransferase activity was high in all groups while serine dehydratase activity was very low.
  • 5.5. Pyruvate kinase and malic enzyme activities which are normally low in cat liver increased after excess MET. Also, glucose 6-phosphate and 6-phosphogluconate dehydrogenases increased.
  • 6.6. Cat liver metabolism showed limited adaptation to an excess dietary intake of methionine compared to that found in rats.
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13.
  • 1.1. The subcellular distribution of the porcine adipocyte beta-adrenergic receptor was studied in fractionated adipocytes.
  • 2.2. The 30,000 g pellet obtained from hypotonically lysed cells contained membrane vesicles and mitochondria; it yielded approx 200–300 fmol dihydroalprenolol-bound receptors/mg protein.
  • 3.3. Activity was increased to about 1000 fmol/mg protein after isolation of a plasma membrane fraction on a Percoll gradient.
  • 4.4. The 5'-nucleotidase, succinate dehydrogenase and lactate dehydrogenase activities were usually enriched in compartments different from the ligand-binding activity.
  • 5.5. Activity of porcine adipocyte 5'-nucleotidase, a purported plasma membrane marker enzyme, was not distributed in the same manner as the beta-adrenergic receptor.
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14.
  • 1.1. The mechanism of action of glyburide (a sulfonylurea) on muscle has been investigated by measuring glucose uptake and glucose transporter (GLUT4) protein levels after chronic glyburide treatment.
  • 2.2. A dietary induced insulin resistant rat model (4 wk of high-fat, high-sucrose feeding) was given glyburide (2mg/kg/day) for 10 days and glucose uptake was measured in a perfused hindquarter preparation.
  • 3.3. Protein levels of the GLUT4 glucose transporter were determined by Western analysis.
  • 4.4. After 7 days of treatment, rats fed glyburide had lower blood glucose concentrations 2 hr (72 ± 5 vs 103 ± 12 mg/dl) and 24 hr (97 ± 7 vs 123 ± 7 mg/dl) after glyburide administration with no difference in serum insulin levels compared to vehicle treated animals.
  • 5.5. Glucose uptake was approx doubled in basal state (0 insulin) in response to glyburide (2.8 + 0.4 vs 1.7 ± 0.2μ mol/g per hr).
  • 6.6. Maximal insulin (100 nM) stimulated glucose uptake tended to be higher in the glyburide treated group, but did not reach statistical significance (8.0 ± 0.7 vs 7.0 ± 0.6 μmol/g per hr).
  • 7.7. Western analysis revealed no significant effect of glyburide on the GLUT4 protein level in skeletal muscle.
  • 8.8. These results suggest that glyburide alters glucose uptake through some mechanism other than alterations in the level of the GLUT4 glucose transporter protein.
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15.
  • 1.1. The specific activity of GMP synthetase was measured in several human tissues and found to be highest in cultured skin fibroblasts, followed by bone marrow, leukocytes, erythrocytes. placenta, and liver.
  • 2.2. The enzyme from fibroblasts was purified approximately 50-fold by ammonium sulfate fractionation and gel filtration.
  • 3.3. The Km values were determined to be 4.9μM for XMP, 270μM for ATP. and 340 μM for glutamine.
  • 4.4. Ammonium sulfate could replace glutamine as the amino donor but was much less efficient.
  • 5.5. The enzyme was specific for ATP as the energy source.
  • 6.6. Unlike the calf thymus enzyme, the human enzyme has no requirement for a reduced sulfhydryl compound.
  • 7.7. Human GMP synthetase is inhibited by ATP, dATP, azaserine, and hydroxylamine.
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16.
  • 1.1. A comparison of proteolytic and protease inhibitory activity, and ecdysteroid levels in body fluids was made between normal larvae of the flesh fly, Sarcophaga bullata, and those that had been water-stressed for two days.
  • 2.2. The course of proteolytic activity in water stressed flies decreases 6 hr after beginning the experiment and remains low in comparison with control flies.
  • 3.3. The course of protease inhibitors exhibits a mirror image pattern to proteases.
  • 4.4. Ecdysteroid pattern shows two peaks in control animals: minor at 24 hr and major at pupariation, in experimental animals: at 1 hr, at 6 hr and at white pupal stage.
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17.
  • 1.1.Juvenile Japanese eels (Anguilla japonica) were fed on a diet supplemented with estradiol-17β (E2) at doses of 25, 50 and 75 mg/kg. The effects on growth, sex distribution and body composition were investigated in two groups of gonadally undifferentiated stages (early and later juvenile stages).
  • 2.2.Feminization (95–100%) was observed in all E2-treated groups.
  • 3.3.The growth rate of fish treated with 25 and 50 mg/kg E2 diet at the early juvenile stage was significantly increased.
  • 4.4.The amount of protein in muscle decreased and that of fat increased in the E2-treated groups except in the early juvenile stage fed with 25 mg/kg E2.
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18.
  • 1.1. An elastase-like enzyme was purified from the pyloric caeca of rainbow trout by hydrophobic interaction, cation exchange and gel-filtration chromatography.
  • 2.2. The approximate molecular weight of the elastase was 27 kDa and the isoelectric point was remarkably basic.
  • 3.3. The pH optimum of this enzyme was 8.0, when assayed with Succinyl-Ala-Ala-Ala-p-Nitroanilide.
  • 4.4. When assayed with Succinyl-Ala-Ala-Ala-p-Nitroanilide, the enzyme activity had a temperature optimum of 45°C, and the enzyme was stable up to this temperature.
  • 5.5. The trout elastase exhibited a higher specific activity than porcine elastase against Succinyl-Ala-Ala-Ala-p-Nitroanilide and elastin-orcein.
  • 6.6. The trout elastase was inhibited by elastatinal, PMSF, TPCK, SBTI and Bowman-Birk inhibitor.
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19.
  • 1.1. Serum from the Pacific hagfish,Eptatretus stouti,contains a complement-like protein (CLP).
  • 2.2. CLP from unfractionated hagfish serum and from affinity-purified preparations binds to yeast cell surfaces.
  • 3.3. Incubation with CLP enhances the phagocytosis of yeast by hagfish leukocytes.
  • 4.4. CLP-mediated opsonization can be inhibited by anti-CLP antibody, EDTA, d(+)mannose and l(+)rhamnose.
  • 5.5. Additional opsomic factors are also in hagfish serum.
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20.
  • 1.1. The optimum pH for measurement of aspartate transcarbamylase activity in oyster tissue was determined to be 9.35 while the optimum temperature was 39.5°C.
  • 2.2. Aspartate transcarbamylase activity varied significantly over short periods of time (hr) possibly due to fluctuations in the amount of food digested.
  • 3.3. The composition of the oyster's diet also affected the levels of aspartate transcarbamylase activity in oyster tissues.
  • 4.4. Those oysters fed an egg yolk-starch diet contained significantly lower aspartate transcarbamylase activity than oysters fed an egg yolk-starch-salmon oil diet or a casein-starch-salmon oil diet.
  • 5.5. The aspartate transcarbamylase activities in oysters fed Phacedactylum tricornutum or a starch diet were not significantly different from the activities in oysters fed the egg yolk-starch diet.
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