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1.
  • 1.1. Electrophoretic analysis of the soluble malate dehydrogenase (sMDH) from 22 subtropical fish belonging to the orders Characiformes, Siluriformes and Perciformes, collected in 10 reservoirs of São Paulo State and in two lakes of Minas Gerais State, Brazil, indicates that at least two sMDH loci, MDH-A1 and MDH-B1, are active. In addition to this latter locus, in Hoplias malabaricus (Erythrinidae, Characiformes), a MDH-A 1,31 isoloci is proposed in order to explain the six-banded pattern detected in all the individuals screened.
  • 2.2. In attempting to explain the multiplicity of compounds detected in 87% of the Geophagus brasiliensis (Cichlidae, Perciformes) specimens analyzed, three hypotheses are proposed: the event of duplication in processing the presence of three loci with a null allele within the MDH-B1, and overdominance.
  • 3.3. In 87% of the species here studied, a bidirectionally divergent pattern of expression of the sMDH loci was observed, in which the least anodal isozyme A2 predominated in liver, and the most anodal isozyme B2 predominated in skeletal muscle. In two siluriform species, Pimelodela gracilis and Hypostomus regani, and in one perciform, Tilapia rendalli, a unidirectionally divergent pattern, in which the isozyme A2 predominated in every tissue analyzed, was observed.
  • 4.4. Polymorphism in at least one of the sMDH loci was detected in 9% of the species studied here: Leporinus friderici (Characiformes) at the MDH-A1 and P. gracilis at both sMDH loci. In L. friderici and Pimelodus maculatus (Siluriformes), rare alleles at the MDH-B1 locus were detected. Polymorphism at the mitochondrial locus was detected in Tilapia rendalli.
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2.
  • 1.1. We used protein gel-electrophoresis to investigate genetic heterogeneity at 33 protein coding loci in a total of 46 blue wildebeest (C. taurinus) kept under different management regimes.
  • 2.2. Average heterozygosity ranged from 2.14 to 4.3% and within-population differences accounted for 97.2% of total relative gene diversity.
  • 3.3. Comparatively little divergence was found between animals sampled from populations with very diverse population sizes and management histories, with the largest genetic distance estimated between any two populations being only 0.0021.
  • 4.4. We discuss our results with particular emphasis on the influence of management history on genetic diversity and divergence in C. taurinus.
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3.
  • 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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4.
  • 1.1. A population of Trigona fuscobalteata from Peninsular Malaysia was analysed for genetic variation at 9 gene-enzyme systems comprising 13 loci.
  • 2.2. Two gene-enzyme systems (phosphoglucomutase and isocitrate dehydrogenase) were polymorphic in the 20 colonies studied.
  • 3.3. Isocitrate dehydrogenase was represented by duplicate genes.
  • 4.4. The number of loci for several enzyme systems appeared to be different from that reported for the Australian stingless bees.
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5.
  • 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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6.
  • 1.1. Two morphotypes of Myliobatis from the demersal fishery off the Rio Grande (Brazil) were studied.
  • 2.2. Thirty-two alleles were detected and resolved by 27 loci.
  • 3.3. Nei's measure of genetic identity was 0.8306 and Thorpe's similarity was 0.6990. Mean heterozygosities observed were 0.1327 for the “DE” morphotype and 0.0409 for the “DL” morphotype.
  • 4.4. Seven loci were fixed differently in the two taxa studied. This indicates the existence of a barrier to gene-flow between them, showing that both morphotypes belong to different species.
  • 5.5. Jaccard's measure of similarity was calculated and a phenogram with the two morphotypes and M. freminvillii was constructed using isoelectric focusing of total soluble proteins. This showed a higher similarity between the two morphotypes of Myliobatis than M. freminvillii.
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7.
  • 1.1. Among the 27 species of Amazon fish belonging to the orders Rajiformes, Clupeiformes, Osteoglossiformes, Characiformes, Siluriformes and Perciformes here analyzed, 56% showed an electrophoretic pattern of five, 7% of four, 30% of three, and 7% of two LDH isozymes, suggesting the presence of both LDH-A1 and LDH-B1 loci. In addition to these loci, the third gene LDH-C1 was detected only in the Osteoglossiform species O. bicirrhosum and in the perciform species P. squamosissimus, with a generalized expression in the first and a restricted in the second.
  • 2.2. Only P. squamosissimus (Perciformes) showed a LDH reversed pattern, in which the A4 is more anodic than the B4.
  • 3.3. Like other vertebrates, in most (93%) of the species here analyzed, a direct correlation between electrophoretic mobility and thermostability was observed. The inactivation temperatures varied from 55°C in the Rajiformes species of 70°C in the Perciformes species.
  • 4.4. Polymorphism in at least one of the LDH loci was detected in 22% of the species studied here: P. castelnaena (Clupeiformes) and B.cf. cephalus (Characiformes) at the LDH-A1 locus, R. myersi and H. unitaeniatus (both Characiformes) at the LDH-B1 and L. agassizi (Characiformes) at both loci.
  • 5.5. No modifications of the classic LDH pattern found by other authors in organisms routinely subjected to hypoxic stress were observed in these Amazon species. In 93% of the species screened here, subjected to considerable hypoxic stress, large daily oscillations in temperature, O2 and CO2 levels, pH, low ionic content, and seasonal drought, a bidirectional pattern of expression of the LDH loci was observed.
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8.
  • 1.1. Bactrocera latifrons fruit flies recovered from four solanaceous fruits (Capsicum annuum, Lycopersicon esculentum, Solanum pseudocapsicum and Solanum melongena) in Peninsular Malaysia were analyzed for a total of 15 gene-enzyme systems comprising 21 loci.
  • 2.2. Eleven loci—aAdh, Aldox, Ald, Est-F, Est-S, Hk-F, Ldh, cMdh, Me, Pep-A and Pep-C—were invariant.
  • 3.3. Of the polymorphic loci, cathodal alcohol dehydrogenase, glucose phosphate isomerase, glycerol-3-phosphate dehydrogenase, hydroxybutyrate dehydrogenase, isocitrate dehydrogenase, anodal malate dehydrogenase and phosphoglucomutase were represented by two alleles each, while hexokinase-S, peptidase-B and phosphogluconate dehydrogenase were represented by three alleles each.
  • 4.4. The proportion of polymorphic loci ranged from 0.28 to 0.33, while the mean heterozygosity ranged from 0.04 to 0.13.
  • 5.5. The genetic variability is associated with the host range.
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9.
  • 1.1. Blood, liver, heart, testis, skin, eye, muscle and kidney samples were obtained from elephants (Loxodonta africana) in the Kruger National Park during a culling programme in April 1992.
  • 2.2. Gene products of 25 protein coding loci in L. africana were examined by horizontal starch-gel electrophoresis.
  • 3.3. Eighteen protein coding loci (72%) displayed monomorphic gel banding patterns whereas only seven (28%) displayed polymorphic gel banding patterns.
  • 4.4. Average heterozygosity values for adults, youngsters and the total population are respectively 0.058, 0.024 and 0.047.
  • 5.5. Relative gene diversities within and between populations are 84% and 16% respectively.
  • 6.6. Two population simulation programmes were utilized to predict the duration of the current variability present in this species, based on current genetic variation and gene transfer from one generation to the next.
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10.
  • 1.1. The phenoloxidase activity, protein and carbohydrate levels were studied for 24 hr in the hemolymph of the migratory grasshopper, Melanoplus sanguinipes after artificial wounding of the insect cuticle or the injection of Beauveria bassiana conidia.
  • 2.2. Injection or wounding induced a primary response and phenoloxidase activity was found to increase within 10–60 min. The values for phenoloxidase activity in viable B. bassiana-injected insects exhibited a secondary response, i.e., an increase 24 hr after injection.
  • 3.3. In wounded insects and those injected with inactivated conidia, the phenoloxidase activity receded after the initial increase and remained at low levels.
  • 4.4. Protein concentrations in the hemolymph increased immediately after infection and wounding and returned to basal levels during the course of the experiment.
  • 5.5. Injection of viable B. bassiana resulted in a gradual increase in the protein concentrations between 12 and 24 hr.
  • 6.6. There was no apparent change in the carbohydrate levels in either B. bassiana-infected or wounded insects.
  • 7.7. These results are discussed in relation to their possible role(s) and interrelationships in the immune response to infection or wounding. Furthermore, we suggest that a “factor” is released after mechanical injury of the integument.
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11.
  • 1.1. Carp red cells were treated with drugs that affect the cell membranes. The water content of the cells and the accumulation of cAMP in the cells were measured in normoxia and in hypoxia using non-stimulated and adrenergically stimulated cells.
  • 2.2. WGA, DIDS + CCCP and A23187 increased the water content of nonstimulated normoxic cells.
  • 3.3. In hypoxia ouabain and DIDS + CCCP increased the water content but cytochalasin B, NPM, DIDS, CCCP and A23187 + CA2+ abolished the hypoxia-induced swelling.
  • 4.4. Any membrane perturbation induced some cAMP formation, Sophora and Anquilla lectins being most potent.
  • 5.5. Also in adrenergically stimulated cells, membrane perturbation generally increased cAMP formation.
  • 6.6. However, cAMP accumulation diminished in cells treated with cytochalasin B, CCCP and DIDS + CCCP.
  • 7.7. The adrenergic swelling of carp red cells was reduced in normoxia by DIDS. NPM and CCCP increased the adrenergic swelling in normoxia to hypoxic level.
  • 8.8. In hypoxia WGA and Anquilla lectin decreased the swelling.
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12.
  • 1.1. A comparative examination of sarcoplasmic proteins of the two nominal European species of angler-fish, Lophius piscatorius and L. budegassa was carried out using isoelectric focusing techniques.
  • 2.2. Two protein bands differing in isoelectric point proved diagnostic for L. budegassa (pI 4.40 and pI 5.75) while a third characterized L. piscatorius (pI 4.65).
  • 3.3. These species-specific protein profiles provide a method of species discrimination independent of morphological criteria.
  • 4.4. Within-species heterogeneity of banding pattern suggested the presence of polymorphic gene loci of potential use in studies of population structure.
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13.
This paper comments on: Low, B. S., Alexander, R. D., and Noonan, K.M. Human hips, breast, and buttocks: Is fat deceptive? Ethology and Sociobiology 8: 249-247, 1987. In it I argue that:
  • 1.1. Sexual selection has probably not been the most important selection pressure on
  • 2.female human body shape.
  • 3.2. Male humans in different cultures find different aspects of the female body attractive
  • 4.and therefore are unlikely to have exerted consistent directional sexual selection on
  • 5.the female body.
  • 6.3. Breast size is not correlated with lactation success.
  • 7.4. Visible hip width is not correlated with parturition success.
  • 8.5. Women would lower their fitness if they tried to deceive men about their internal
  • 9.pelvic dimensions.
  • 10.6. There are many alternative hypothesis to explain the existence of fat onwomen's
  • 11.breast, hips, and buttocks.
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14.
  • 1.1. We studied the morphology and contractile properties in marginal sphincters isolated from anemones from different environments.
  • 2.2. Sphincters from specimens from protected areas are ovoid or roughly square shape. Oval sphincters have increased number of mesogloeal branches and the main axis is thickened. Roughly square sphincters have irregular borders, mesogloeal axes of uniform thickness and homogeneous branching.
  • 3.3. Specimens from exposed areas have sphincters with an ovoid shape and dichotomous branching.
  • 4.4. Sphincters of specimens from partially protected areas show transition forms.
  • 5.5. Under stimulation with KCl at different concentrations, sphincters of anemones from exposed environments contract faster and develop higher isometric forces than muscles isolated from specimens of protected areas.
  • 6.6. It was concluded that sphincters of anemones from different environments have a morphology and a physiological response adapted to the milieu.
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15.
  • 1.1. A female specific protein (FSP, vitellogenin) in hemolymph and its related ovarian protein (vitellin) of Pandalus kessleri were studied by means of electrophoretical and immunological procedures.
  • 2.2. The vitellin was purified from vitellogenic ovaries using hydroxylapatite, DEAE cellulose and Sepharose 6B columns, consecutively.
  • 3.3. The vitellin had a molecular weight of approximately 560 kD and was composed of two subunits, 81 and 110 kD, respectively.
  • 4.4. The vitellogenin concentrations in the hemolymph increased as vitellogenesis in the ovarian oocytes advanced and dropped markedly after the release of mature eggs.
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16.
  • 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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17.
  • 1.1. Digestibilities of feed, and transit and retention time of fluid and particle digesta marker measured in nutrias (Myocaster coypus) and guinea-pigs (Cavia porcellus) fed on a diet containing 50% alfalfa.
  • 2.2. The digestibility of fibre was higher in the nutria, along with the longer retention time of digesta.
  • 3.3. The liquid and particle marker were similarly excreted, suggesting no separation mechanism in the gastrointestinal tract of both the animals.
  • 4.4. The apparent digestibility of protein in the nutria was superior to the guinea-pig and other small hindgut fermenters, suggesting that the contribution of coprophagy on protein nutrition of nutrias is significant.
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18.
  • 1.1. Patterns of histone variants from three diptera, Ceratitis capitata, Dacus oleae and Drosophila melanogaster were compared to mouse and to Plodia interpunctella variant patterns.
  • 2.2. The three diptera contain histones which comigrate on two dimensional gels with H3.2, H3.3 and H4 in mouse and Plodia. H2A.1 and H2B.1 comigrate with Plodia H2A.1 and H2B.1 and are different from mouse, whilst H2A.Z has a different mobility to that of Plodia and mouse.
  • 3.3. The iodinated peptides obtained from H2A.1 and H2A.2 of the diptera studied are compared to mouse and Plodia H2A.1 and H2A.Z peptides.
  • 4.4. The histone variants from three developmental stages, larval, pupal and adult of the three diptera were identified and compared.
  • 5.5. The same histone variant pattern is found through all stages of development.
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19.
  • 1.1. Hormonal regulation of apolipoprotein E (apoE) gene expression by insulin and thyroid hormone was studied in a human hepatoma cell line, HepG2.
  • 2.2. Changes at the mRNA level, mRNA translation, in vivo synthesis and secretion were monitored.
  • 3.3. Both insulin and triiodothyronine were found to have no significant effect on apoE mRNA levels.
  • 4.4. Insulin treatment caused an inhibition of: (a) the in vitro translation of endogenous apoE mRNA in a HepG2 cell-free system (25%), and (b) the incorporation of radioactivity into newly-synthesized apoE in an in vivo pulse-chase labeling experiment (32%).
  • 5.5. Interestingly, apoE secretion rate was found to be significantly reduced with insulin (84%) suggesting that a major portion of newly-synthesized apoE may be shunted into a degradative pathway.
  • 6.6. Using a similar experimental approach, triiodothyronine showed no significant effect on the rate of apoE synthesis or translation (6–15% decrease), however a slight reduction (20%) in secretion rate was shown.
  • 7.7. Overall, apoE gene expression does not appear to be influenced by triiodothyronine significantly but is modulated by insulin at the translational and post-translational level.
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20.
  • 1.1. The total body water, lipid content, and cuticular permeability of fungus infected and uninfected German cockroaches, Blattella germanica, were examined.
  • 2.2. Infected adult cockroaches weighed less and had significantly more body water than did uninfected specimens of the same size.
  • 3.3. Uninfected medium-size nymphs weighed significantly more than infected nymphs, but there was no difference in body size between infected and uninfected small nymphs.
  • 4.4. Cuticular permeability and lipid content of infected and uninfected cockroaches was not significantly different.
  • 5.5. Sequestering of water by the fungal cells is discussed as a possible factor in the pathology of this fungal parasite.
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