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1.
  • 1.1. The heterogeneity of blood proteins (including haemoglobin) of adult and subadult male and female Eiderducks, and the egg albumen proteins was studied, in relation with some behavioural properties, as nest-site preference and being migratory or sedentary.
  • 2.2. The blood proteins demonstrate a high degree of multiplicity, with two different patterns in the pH range of 5.3–5.7; half the number of blood samples showed two “single” bands. The other half two “double” bands.
  • 3.3. The egg albumen proteins show three different patterns, indicating three phenotypes (aa, ab and bb), occurring in four habitat types.
  • 4.4. No relation exists between blood protein or egg albumen protein patterns and behavioural aspects of habitat preference for nesting sites.
  • 5.5. The Eiderducks of the Vlieland colony are residents, with a high frequency of b-allele, compared to the b-frequency of the Forvie colony birds.
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2.
  • 1.1. Milk samples of 4 ml or more were obtained from guinea pigs (Cavia porcellus), dairy cattle (Bos taurus), horses (Equus caballus) and humans (Homo sapiens). The milks were analysed for minerals including calcium (Ca), phosphorus (P), magnesium (Mg), potassium (K) and sodium (Na) by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES).
  • 2.2. Calcium was approximately twice as concentrated in guinea pig milk as in cows' milk, which was twice as much as the level in mares' milk, and this, in turn, was twice as concentrated as human milk.
  • 3.3. The ratio of Ca to P in guinea pig milk was 1.66:1, while it was 1.24:1 in cows' milk, 1.56:1 in mares' milk and 2.07:1 in human milk.
  • 4.4. Potassium was the most abundant mineral in the milks of cows, mares and humans, but not in guinea pig milk, and was much higher in cows' milk than in others.
  • 5.5. Sodium was highest in guinea pig milk with cows' milk being a close second.
  • 6.6. Magnesium was one-tenth as concentrated as Ca.
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3.
  • 1.1. Spore coat extracts from Bacillus thuringiensis subspecies kurstaki and israelensis and Bacillus cereus T and B. cereus NRRL 569 were characterized by polyacrylamide gel electrophoresis in sodium dodecyl sulfate and by amino acid analysis.
  • 2.2. Both B. cereus spore coats had similar electrophoretic profiles.
  • 3.3. The B. thuringiensis spore coats contained crystal proteins as major components as well as lower mol. wt proteins.
  • 4.4. B. thuringiensis subsp. israelensis had a unique coat protein profile which was different from B. cereus and B. thuringiensis subsp. kurstaki coats.
  • 5.5. Insecticidal activity of spores against the tobacco hornworm, Manduca sexta, and the mosquito, Aedes aegypti, also was determined.
  • 6.6. B. thuringiensis subsp. kurstaki spores were lethally toxic to the tobacco hornworm (Lepidoptera) larvae, whereas spores of the other subspecies were not.
  • 7.7. Except for subspecies israelensis, none of the spores was effective against the mosquito (Diptera) larvae.
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4.
  • 1.1. Isolated ovaries of egg laying females synthesize and secrete three yolk proteins (two vitellogenins and chromoprotein 2).
  • 2.2. The contribution of ovarian tissue to total yolk protein production is very small, the major site of synthesis of the three yolk proteins being the fat body.
  • 3.3. There is a time lag between yolk protein synthesis by the fat body and yolk protein sequestration by the ovary.
  • 4.4. In egg laying females, within 1 hr after the synthesis of both vitellogenins by the fat body, they appear in the oocytes as vitellins.
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5.
  • 1.1. Seasonal changes of circulating blood parameters of Natrix n. natrix were evident and involved both sexes to the same extent.
  • 2.2. A significant decrease in red cell count, haematocrit and haemaglobin concentration in the mating period, and an increase in those parameters and mean cell volume in autumn were observed, and haemodilution during winter torpor.
  • 3.3. The changes during the breeding season had probably a hormonal background; in winter, they resulted first of all from a decreased erythropoietic activity and, to a lesser extent, from an increased red blood cell breakdown rate. However, the possibility that some erythrocytes were withdrawn from the circulation cannot be excluded.
  • 4.4. Winter lymphocytopenia, eosinocytopenia and neutrophilic granulocytosis in females during egg laying were expressions of changes of leucocyte formula.
  • 5.5. Seasonal cyclicity was found only with respect to the white cell count in males and the eosinophile fraction in males and females.
  • 6.6. Probable reasons for, and mechanisms of the changes in blood composition are discussed.
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6.
  • 1.1. The urate, urea and ammonia content of the whole egg of the Japanese quail was measured in late incubation in eggs subject to different rates of water loss.
  • 2.2. High rates of water loss substantially increased egg urate content, but had little or no effect on urea or ammonia content.
  • 3.3. Allopurinol, an inhibitor of urate synthesis, reduced egg urate content to low levels, but produced no effect on urea content, and a small reduction in ammonia content.
  • 4.4. The urea concentration of the embryo was lower than in allantoic fluid.
  • 5.5. It is concluded that urate production by the avian embryo is primarily concerned with the modification of allantoic fluid composition.
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7.
  • 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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8.
  • 1.1. A method is described for the accurate and rapid measurement of protein- and non-protein-bound cortisol by miniature gel filtration in small volumes of plasma, e.g. of rodents.
  • 2.2. Binding of cortisol by guinea pig plasma proteins is strongly reduced at elevated temperature (4°C: 102 ± 12ng/ml; 40°C: 5 ± 2 ng/ml).
  • 3.3. Incubation of guinea pig plasma with 1–5000 ng cortisol resulted in a dose-dependent increase in cortisol bound to proteins (specific binding by corticosteroid binding globulin: 230 ± 12 ng/ml).
  • 4.4. Administration of 20 IU (1–24)ACTH induced a significant increase of total protein-bound and non-protein-bound cortisol.
  • 5.5. Values reported in this study agree well with those of previous investigations, in which bound and non-bound glucocorticosteroids were separated by gel filtration on large Sephadex® columns.
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9.
  • 1.1. The degradation of the bone matrix proteins osteocalcin, osteonectin and α2HS-glycoprotein by human cathepsins B and L and human osteoclastoma cathepsins has been investigated.
  • 2.2. Intermediate degradation products (Mr > 12kDa) were not observed during the digestion of α2HS-glycoprotein and osteonectin by cathepsins B and L although they were observed with some of the osteoclastoma cathepsins. Most of the osteoclastoma cathepsins were capable of degrading these two proteins to small peptides at comparable rates.
  • 3.3. Each cathepsin produced a different pattern of osteocalcin degradation products.
  • 4.4. The extensive range of non-collagenous proteins in bone matrix may necessitate the production by osteoclasts of cathepsins with different specificities during bone resorption.
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10.
  • 1. Respiratory properties of piranha blood are distinguished from those of other fish primarily by the high CO2 buffering capacity (ΔHCO3/ΔpH= 19.6mmol/l for oxygenated blood and 39.1 mmol/l for deoxygenated blood).
  • 2. The concentration of nucleoside triphosphates (NTP) and the half-saturation tension (P50) of whole blood were found to be inversely related to body size.
  • 3. The higherP50 in smaller fish, analogous to values obtained in previous studies involving interspecies comparisons, could be adaptive to a higher weight-specific metabolic rate.
  • 4. Both ATP and guanosine triphosphate (GTP) lowered the oxygen affinity of purified hemoglobin solutions, accounting for the size-dependent correlation ofP50 and NTP concentration in whole blood.
  • 5. While similar in concentration in red cells, GTP is more potent than ATP as an allosteric modifier of hemoglobin function.
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11.
  • 1.1. The phosphorylation of Escherichia coli proteins was analyzed comparatively before and after induction of the SOS response in a temperature-sensitive mutant strain.
  • 2.2. The presence of phosphorylated proteins was evidenced by gel electrophoresis and autoradiography after labelling with radioactive orthophosphate in vivo or radioactive adenosine triphosphate in vitro.
  • 3.3. Significant changes in the intensity of protein labelling were observed upon induction of the SOS functions: six proteins were found to be more phosphorylated while two others were less phosphorylated. Moreover, five additional proteins appeared to become phosphorylated exclusively during the SOS response. The molecular mass and isoelectric point of these various proteins were determined.
  • 4.4. For most proteins, the changes in the pattern of protein phosphorylation were concomitant with variations in the amount of protein synthesized.
  • 5.5. The changes in the pattern of phosphoproteins observed during the SOS response were not due to the temperature shift required experimentally for expressing the SOS phenotype.
  • 6.6. Phosphorylation was found to be catalyzed by protein kinases that modify amino acid residues at hydroxyl groups in protein substrates.
  • 7.7. Both in vivo and in vitro studies brought evidence that neither RecA nor LexA, the two key regulatory proteins of the SOS functions, were capable of undergoing phosphorylation.
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12.
  • 1.1. New minor proteins were isolated from chicken and quail egg whites and were named the ovoglycocomponent.
  • 2.2. They migrated on polyacrylamide-gel electrophoresis as a single band without any contaminations.
  • 3.3. They contain a considerable amount of carbohydrates, of which hexosamine was much higher in the chicken than in the quail.
  • 4.4. The molecular weights of the chicken and quail ovoglycocomponents estimated from gel filtration were approx 56,000 and 49,000, respectively.
  • 5.5. The isoelectric points were measured as 5.1 for the chicken and 5.4 for the quail.
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13.
  • 1.1. Propanol extracts of the sponge Tethya aurantia (Demospongiae) were fractionated, guided by bioassay, for a component with negative chronotropic and inotropic activity on isolated guinea pig atria.
  • 2.2. The bioactive component was found to be adenosine. These extracts also contained allantoin.
  • 3.3. This intermediate in the sequence of degradation of purines was unexpected, since it has been reported only once before to occur in marine invertebrate animals.
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14.
  • 1.1. Oxygen equilibrium curves were measured on trout red blood cell suspensions at pH 7.8 and 8.4 at 15, 20 and 25 C. Normal red cells and red cells that had been depleted of their ATP content were used.
  • 2.2. The equilibrium data were fitted to the Adair's model and the enthalpy (ΔH) and entropy (ΔS) changes for the first and fourth steps of oxygenation and for overall oxygenation were calculated from the temperature dependencies of the Adair constants.
  • 3.3. For normal red blood cells, the apparent heat for the first oxygenation step, δh1, is close to zero.
  • 4.4. Temperature insensitivity of this step at physiological pH, combined with a large pH dependence, probably denotes a property of Hb4, the Root effect Hb of trout blood.
  • 5.5. At pH 7.8, ΔH4 is about —4kcal/mol, a small value which may be attributed to the large release of Bohr protons that occurs at the last oxygenation step and corresponds to an endothermic process which opposes to the exothermic oxygenation of the haem.
  • 6.6. The ΔH4 value appears to have a large influence on the enthalpy for overall oxygenation.
  • 7.7. Results for ATP-free red cells are consistent with a mere increase in the intracellular pH and suggest that ATP has no specific effect at and above pHi ~ 7.7.
  • 8.8. Effects of temperature and pH on trout red blood cell isotherms emphasize the primary importance of the major component of trout blood, namely Hb4, in trout blood functional properties.
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15.
  • 1.1. Glucose utilization was measured in human, pig, cow, rabbit, mouse and rat red blood cells. Mean values are variable from species to species and range from 0.27 μmol/hr/ml RBC for pig erythrocytes to 2.85 μmol/hr/ml RBC in mouse red cells.
  • 2.2. The amount of glucose metabolized through the pentose phosphate pathway ranges from 2.1 to 7.0% of the total glucose utilized.
  • 3.3. Variable recycling values have been obtained for the red blood cells of the species studied but with the exception of mouse (14 nmol/hr/ml RBC) all the other values do not show great differences.
  • 4.4. The hexokinase levels of the erythrocytes studied when correlated with the glucose utilization and the pentose phosphate pathway show that this enzyme could play a central role in the regulation of glucose metabolism.
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16.
  • 1.1. The distribution and physicochemical properties of proteins known to bind cyclic AMP in vitro and methodological aspects of their interaction with ligands is reviewed.
  • 2.2. The interaction between such proteins and cyclic AMP is discussed, the allosteric binding of the nucleotide to cyclic AMP dependent protein kinase type I being considered in detail.
  • 3.3. The use of naturally occurring binding proteins in assays for cyclic AMP is briefly reviewed.
  • 4.4. Finally, some aspects of the control of cyclic AMP binding in the intact cell are considered.
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17.
  • 1.1. Platelets bind specifically to lactoferrin. A significant similarity between human lactoferrin and some bovine milk proteins has been established.
  • 2.2. Because of the structural homology of lactoferrin and cows milk proteins they are able to influence lactoferrins regulatory function on the level of its binding to membrane receptors on platelets.
  • 3.3. An inhibitory effect of bovine α-lactalbumin and of β-lactoglobulin on lactoferrin-receptor interaction was shown.
  • 4.4. Bovine α-lactalbumin competes with lactoferrin for the binding sites.
  • 5.5. Scatchard plot analysis of data shows one binding site for lactoferrin in the presence of α-lactalbumin with an affinity constant, Ka = 0.46 × 109 mol/1 and 335 receptors/cell.
  • 6.6. The inhibitory effect of β-lactoglobulin reaches 62% and is different for the common fraction ⨿-lactoglobulin and the genetic variants β-lactoglobulin A and B.
  • 7.7. β-lactoglobulin does not compete with lactoferrin for the membrane receptors.
  • 8.8. Bovine casein and egg lysozyme stimulate 59Fe-lactoferrin binding to the receptors. The mechanism of these effects is still unknown.
  • 9.9. Tested alimentary antigens are able to interact with lactoferrin and also with some platelet membrane structures.
  • 10.10. Established changes in lactoferrin binding to the platelet membrane might be in relation to lactoferrins regulatory function and (or) eliminating mechanisms of these alimentary antigens.
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18.
  • 1.1. Kinetic aspects of the enzyme UDP-galactose 4-epimerase in crude homogenates of the albumen gland of the snail Lymnae stagnalis were estimated. The mean values of the Km for UDP-galactose and for NAD are 0.343 and 0.097 mM, respectively. The enzyme is inhibited by NADH. It is inactivated by freezing and raised temperature (25°C), but it can be reactivated by NAD.
  • 2.2. In the albumen gland the epimerase activity is 10–100 times higher than in other tissues, reflecting the high turnover of glucose to galactose, essential for the synthesis of galactogen in this organ.
  • 3.3. In fed snails long day conditions stimulates albumen gland epimerase activity, coinciding with high egg production.
  • 4.4. In starved snails a fairly high residual activity of the enzyme is maintained, irrespective of photoperiod or egg production.
  • 5.5. Trematode infection leads to a considerable reduction of the epimerase activity.
  • 6.6. The results indicate that the epimerase activity in fed snails, when the gland shows a regular release, reflects long-term adaptations (photoperiod). In starved and parasitized snails, when no regular release or product occurs, a basic epimerase activity is maintained. This might be important for a rapid restoration of egg production after the termination of adverse conditions.
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19.
  • 1.1. Glycation is non-enzymatic modification of proteins by sugars in which not only structural but also biological properties of proteins are altered.
  • 2.2. Our in vitro experiments show that incubation of myofibrillar proteins with ribose results in sugar attachment to proteins and at the same time myofibrillar ATPase activity is lowered.
  • 3.3. DETAPAC, aminoguanidine and 2-mercaptoethanol all partially block myofibrillar protein glycation and ATPase activity is less inactivated.
  • 4.4. The dependence of ATPase activity of myofibrils incubated with ribose on the amount of 2-mercaptoethanol present suggests that also modification of SH groups is involved in enzyme inactivation.
  • 5.5. Electrophoretic studies revealed that heavy chains of myosin, actin, and tropomyosins are proteins which are mainly glycated in vitro.
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20.
  • 1.1. The effects of trypsin and chymotrypsin on HCO3/Cl exchange through red blood cell membranes of humans and trout were studied.
  • 2.2. To measure the anion exchange we used a right-angle light-scattering technique by applying the Jacobs-Stewart cycle in ammonium solution and the osmotiration method at constant cell volume.
  • 3.3. The Cl flux in human red blood cells remained unaltered after treatment with external trypsin and chymotrypsin while in trout red blood cells the flux decreased.
  • 4.4. This partial inhibition of anion transport in fish, ranging from 30 to 40%,suggest that one or several of the cleavage sites in band 3 protein, essential for anion transport function, are exposed in fish red blood cells.
  • 5.5. In human red blood cells the fragments of band 3 which are affected by proteolytic digestion, retain their tertiary structure because there is no influence on anion transport.
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