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1.
  • 1.1. The age related flight performance of males and females of the blowfly Phormia terrae novae was studied and the influence of artificially fed glucose determined.
  • 2.2. Maximum flight ability—measured as flight distance, duration and initial velocity—was achieved during the first week after emergence, thereafter the flight performance drops precipitously between the 12th and 17th day of adult life.
  • 3.3. Males and females, fed and unfed individuals, show no difference in their time course of flight ability.
  • 4.4. The possible causes of the programmed loss of flight performance were discussed with regard to histological and enzyme activity changes observed at the same and other species.
  • 5.5. The biological significance of this physiological age effect was revealed.
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2.
  • 1.1. Membrane modifications and junctional structures involved in neuron-glia exchange in crustaceans are reviewed, including some new observations on the crayfish Procambarus clarkii.
  • 2.2. Neuron cell bodies and associated glia interact through trans-glial channels, modified neuronal endocytosis and gap-like junctions.
  • 3.3. Tubular lattices, trans-glial channels, endocytosis and capitate projections give support to axo-glial relationships.
  • 4.4. Unidentified neuron-glia membrane appositions have been also found in neuropile.
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3.
  • 1.1. NADH-dependent isocitrate dehydrogenase has been purified 110-fold from the crude extract of the flight muscle mitochondria of Aldrichina grahami.
  • 2.2. The purification procedure involved Triton X-100 treatment of isolated mitochondria, column chromatography on DEAE-cellulose, Affi-gel blue, and P-cellulose.
  • 3.3. The purified enzyme was homogeneous by criteria of the polyacrylamide gel electrophoresis.
  • 4.4. The enzyme of the blowfly contains more acidic amino acids and less hydrophobic amino acids than that of pig heart.
  • 5.5. The molecular weight was determined to be 330,000 daltons. The subunit construction differs from ghat of mammalian isocitrate dehydrogenase.
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4.
  • 1.1. The lipid composition of lipophorin from the Colorado potato beetle, Leptinotarsa decemlineata Say, was analyzed.
  • 2.2. This insect lipophorin contains 44% lipid and is characterized by large amounts of hydrocarbons and small amounts of diacylglycerol.
  • 3.3. This is the first observation of a diacylglycerol-poor insect lipophorin in haemolymph.
  • 4.4. Since the main energy source for flight in the Colorado potato beetle is proline, the low diacylglycerol content in lipophorin must be related to its peculiar flight metabolism.
  • 5.5. This lipophorin, however, can still take up appreciable amounts of diacylglycerol from the locust fat body. Hydrocarbon uptake by this lipophorin was also demonstrated.
  • 6.6. The main function of this lipophorin therefore seems to be transport of hydrocarbons from oenocytes to the cuticle.
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5.
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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6.
  • 1.1. The lipid components of three animals, the rock crab Nectocarcinus integrifons, the rock flathead Platycephalus laevigatus and the southern garfish Hyporhamphus melanochir, feeding in the seagrass beds at Corner Inlet, Victoria, Australia have been examined in detail in order to provide further information on seagrass community structure.
  • 2.2. Biological marker compounds detected within animal gut content material were used to recognize dietary sources and then utilized by community members.
  • 3.3. Both H. melanochir and N. integrifons have been shown to ingest and to varying degrees incorporate seagrass lipid material, thus further confirming the importance of seagrass carbon in the Corner Inlet environment.
  • 4.4. The southern sea garfish H. melanochir is observed to remove C18 PUFAs (polyunsaturated fatty acids) from ingested seagrass material.
  • 5.5. Seagrass sterols are altered during incorporation into the lipids of this fish.
  • 6.6. Lipid-rich digestive juices play a role in the digestive processes of all three animals.
  • 7.7. Components tentatively identified as (NMI) (non-methylene interrupted) fatty acids have been detected in the lipids of the garfish H. melanochir and the crab N. integrifons.
  • 8.8. The fecal material of all three animals represent possible sources of these lipids (NMI acids) in Corner Inlet sediments.
  • 9.9. Based on lipid compositional data, N. integrifons feeds on Posidonia australis detritus and associated epiphyte material.
  • 10.10. The removal of both plant and epibiota cellular lipids along the digestive tract of the crab was observed, although structural components such as long chain mono- and α,ω-dicarboxylic acids, which have been previously recognized as seagrass marker lipids are not directly absorbed.
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7.
  • 1.1. The locust vitellogenin (VTG) receptor which is embedded in oocyte plasma membranes is a glycoprotein.
  • 2.2. With various lectins oligosaccharide units have been identified, among them neuraminic acid linked to Gal or GalNAc, mannose chains, Gal linked to GalNAc or GlcNAc and fucose linked to GlcNAc.
  • 3.3. With specific enzymes it could be shown that mannose and most other oligosaccharides are O-linked while others like fucose are N-linked.
  • 4.4. Enzymatic removal of all O-linked carbohydrates resulted in a drop of the molecular mass of the receptor protein from 200,000 to 110,000.
  • 5.5. A total of N- and O-linked oligosaccharides of 54% was calculated.
  • 6.6. The isoelectric point of the receptor was found to be at pH 3.4 increasing slightly after removal of neuraminic acid.
  • 7.7. Removal of neuraminic acids destroyed the binding ability for VTG.
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8.
《Insect Biochemistry》1981,11(4):423-427
  • 1.1. Measurements of maximal enzyme activities were combined with an electrophoretic study of isozyme make-up in an examination of triglyceride, diglyceride and monoglyceride lipases from the flight muscle, fat body and gut of the cockroach, Periplaneta americana and the locust, Locusta migratoria and from the flight muscle and fat body of the moth, Polia adjuncta.
  • 2.2. Tri-, di- and mono-glyceride lipases were present in all tissues of the insects with diglyceride lipase ≥ triglyceride lipase activity in all cases and monoglyceride lipase ≥ diglyceride lipase activity in locust and moth.
  • 3.3. In the flight muscle, a strong correlation was found between the activities of lipases and the known use of lipid as a fuel for flight in these insects. Lipase activities were lowest in the cockroach (a carbohydrate-based flight metabolism), intermediate in the locust (both carbohydrate and lipid-fueled flight), and highest in the moth (a non-feeding, lipid-catabolizing adult) flight muscle.
  • 4.4. Polyacrylamide gel electrophoresis, using substrate-impregnated gels and stained for fatty acids released by lipase action, demonstrated the presence of tissue specific isozymes of tri-, di- and mono-glyceride lipases in the three insects. In addition, some, but not all, tissues showed multiple molecular forms of one or more of the lipases.
  • 5.5. Diglyceride and monoglyceride lipase activities in both flight muscle and fat body of the insects coelectrophoresed suggesting the possibility that these two lipase activities might be catalyzed by a single enzyme protein.
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9.
  • 1.1. Rhizostoma pulmo, Aurelia aurita and Actinia equina, the most widespread representatives of Coelenterata in Black Sea have been analysed and the occurrence of 20 sterols has been found.
  • 2.2. Dinosterol and demethyldinosterol as well as a number of short side chain sterols have been found in Scyphozoa for the first time.
  • 3.3. The occurrence of coprostanol in marine invertebrates has been shown for the first time.
  • 4.4. Five groups of sterol esters were found, containing fatty acids with different polarity.
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10.
  • 1.1. Mitochondria with high respiratory control ratios (RCR) have been isolated from the ventricle of the marine clam Mercenaria mercenaria.
  • 2.2. Proline is the preferred substrate of the mitochondria of the ventricle based on state 3 rates.
  • 3.3. Pyruvate, ornithine and succinate are oxidized at rates 3/4 that of proline.
  • 4.4. α-Glycerophosphate was oxidized at rates 1/2 that of proline.
  • 5.5. The pH optimum for proline oxidation lies between 6.5 and 7.5 based on RCR and ADP/O and between 7.0 and 7.4 based on state 3 rates.
  • 6.6. KCl concentrations between 250 and 450 mM gave optimal values for the oxidation of proline based on RCR and state 3 rates.
  • 7.7. KCl concentration had little effect on ADP/O between 100 and 850 mM.
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11.
  • 1.1. Ninety-one pairwise comparisons of 14 populations yielded highly significant T2 values for inter-breed differences while four subpopulations of Thoroughbred horses were nearly identical.
  • 2.2. Generalized Mahalanobis distance was carried out by comparing simultaneously all 14 populations with respect to 26 variables (phenotypes) contributing most to the discriminant function.
  • 3.3. The number of variables could be reduced to 12 phenotypes in final comparisons.
  • 4.4. In general the calculated distances agreed with known relationships between horse breeds.
  • 5.5. However the obtained distances are thought to be biased due to the nature of selected phenotypes which do not always correspond to “breed-markers”.
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12.
  • 1.1. Drosophila mettleri have been found feeding but not breeding on decaying stems of senita cactus, the normal host for Drosophila pachea.
  • 2.2. Alkaloids were extracted from senita stems and used in tests of egg-to-adult viability, developmental rate, and adult longevity.
  • 3.3. The results show that developmental rate is not appreciably affected by senita alkaloids.
  • 4.4. In general, D. mettleri was less affected by the alkaloids with respect to egg-to-adult viability and adult longevity than D. pachea at concentrations which are fatal to other desert Drosophila.
  • 5.5. Tolerance to alkaloids gives D. mettleri an ecological advantage.
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13.
  • 1.1. An alkaline p-nitrophenylphosphate phosphatase has been purified 440-fold from extracts of Hatobacterium halobium.
  • 2.2. The enzyme has an apparent molecular weight of 24,000.
  • 3.3. A Km value for p-nitrophenylphosphate of 1.12mM has been found under optimal conditions.
  • 4.4. The enzyme is selectively activated and stabilized by Mn2+.
  • 5.5. It requires high salt concentrations for stability and maximum activity.
  • 6.6. It displays an unusual restricted substrate specificity of 25 phosphate esters tested, only phosphotyrosine and casein were hydrolysed besides p-nitrophenylphosphate.
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14.
  • 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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15.
  • 1.1. Over an 8-year period, 19 biochemical parameters have been determined at various ages in the blood serum of 92 clinically healthy Lechwe waterbucks (Kobus leche), 33 males and 59 females.
  • 2.2. Significant differences have been noted with age. In neonates, the lowest values of total proteins, glucose, creatinine, urea, AST, ALT and iron have been noted; the highest ones have been seen for cholesterol, alkaline phosphatase, calcium and phosphorus.
  • 3.3. With regard to sex, raised values of glucose, urea, alkaline phosphatase and ALT, and lowered values of cholesterol, have been noted in juvenile females compared with males of the same age.
  • 4.4. In adult females, higher levels of urea and cholesterol and lower levels of glucose, triglycerides and natrium have been recorded compared with males.
  • 5.5. With sex and age, no significant changes have been found in the levels of GGT, magnesium, chlorides and copper.
  • 6.6. Out findings are discussed with those abstracted from the literature for related species.
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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. A potentiometric method for the assay of cholinesterase has been proposed and compared with a colorimetric assay.
  • 2.2. Main kinetic parameters of cholinesterase from Hypostomus punctatus brain were determined indicating that true acetylcholinesterase is by far the predominant enzyme in the brain of this fish.
  • 3.3. We have compared our data with published results described from other fish species.
  • 4.4. The enzyme inhibition achieved after 3 hr incubation of brain homogenates with ethyl-parathion have indicated that this enzyme shows a characteristic organophosphorous sensitive behavior.
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18.
  • 1.1. In vivo metabolism of a secondary alcohol in Drosophila melanogaster and its effects on alcohol dehydrogenase (ADH) have been studied.
  • 2.2. ADH-mediated breakdown of the secondary alcohol, propan-2-ol, was the main source of the acetone produced.
  • 3.3. Acetone formation declined and stopped ultimately, suggesting inhibition of ADH activity in vivo which has been confirmed in in vitro studies.
  • 4.4. A powerful ketone-trapping agent, semicarbazide, did not restore the ADH activity in vitro, whereas aldehyde substrates of ADH did restore activity.
  • 5.5. The final formation of a dead-end ADH:NAD-acetone ternary complex has been proposed and its consequences discussed.
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19.
  • 1.1. Three monoclonal antibodies have been produced which neutralize in vitro the haemolytic activity present in tentacle extracts of the box jellyfish (Chironex fleckeri).
  • 2.2. Two of these monoclonal antibodies bound specifically to a component of relative molecular mass 50,000 in tentacle extract on Western blots.
  • 3.3. This binding only occurred when the extracts were electrophoresed under non-reducing conditions.
  • 4.4. The third monoclonal antibody did not display binding to Western blots of tentacle extract under any of our experimental conditions.
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20.
  • 1.1. Myoglobins from heart and skeletal muscle of turtles were analyzed by thin-layer isoelectric focusing.
  • 2.2. Within the subfamily Emydinae, variation in the occurrence of two myoglobin electromorphs (pI 6.8 and 6.9) was detected.
  • 3.3. Patterns of myoglobin polymorphism support dividing the Emydinae into two subfamilies and help resolve controversial theories on relationships of the genus Deirochelys.
  • 4.4. Possible adaptive significance of the myoglobin variants (isoforms) remains to be determined.
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