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1.
  • 1.1. The mechanism of action of disulfiram on the respiratory electron transport system of the liver mitochondria was studied in vitro.
  • 2.2. Disulfiram inhibited the respiration supported by malate-glutamate as well as succinate.
  • 3.3. Mitochondrial respiration inhibition was dependent upon alteration of —SH groups.
  • 4.4. The inhibitory action of disulfiram might be related to the crosslinking of several proteins of the inner mitochondrial membrane.
  • 5.5. The effects described above could be attributed to disulfiram per se and not to the main metabolite diethyldithiocarbamate.
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2.
  • 1.1. The change in color of the lateral stripe of the neon tetra, Paracheirodon innesi, is due to the motile activity of the iridophores which are sensitive to light and adrenergic stimuli.
  • 2.2. The light-reflecting platelets within the iridophore were found to be arranged regularly, making an acute angle of depression with respect to the median plane of the body.
  • 3.3. When epi-illumination was applied to the skin piece laid horizontally on the stage of a light microscope (with an angle of incidence of about 40°) and the wavelength of the reflected light introduced into the objective lens was monitored, the spectral peak was found to shift to longer wavelengths with the application of K+-rich saline, with a simultaneous decrease in reflectance.
  • 4.4. Using the identical fiber assembly for light irradiation and measurements of reflected light, we found that the angle of incident light producing the maximum reflectance, which corresponded to the inclination of the platelets, increased with the shift in the spectral peak toward longer wavelengths.
  • 5.5. It appears from our results that a change in the angle of inclination of the platelets triggered by adrenergic stimuli may give rise to a change in the distance between the platelets which, in turn, leads to the shift in the spectral peak.
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3.
  • 1.1. d-Alanine has been found in appreciable amounts in the eggs and embryos of the sea urchin Paracentrotus lividus.
  • 2.2. The content of d-alanine, expressed as pmol/egg or embryo, is 1.32 in the egg, 0.81 in the blastula, 0.54 in the gastrula and 0.60 in the pluteus.
  • 3.3. The percentage of d-alanine with respect to the total alanine (d + l) decreases during embryonic development.
  • 4.4. d-Amino acid oxidase, d-alanine transaminase and d-alanine racemase activities were found neither in eggs nor in embryos.
  • 5.5. Therefore, it does not appear likely that d-alanine is subject to oxidative metabolism.
  • 6.6. The decrease in this d-amino acid during development may be due to its utilization in the synthesis of a more complex molecule.
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4.
  • 1.1. The luminescence properties of the cocoon spun by the larvae of the Oriental hornet was studied.
  • 2.2. When light was shined upon the cocoon caps with excitation wavelengths of 240, 290 or 312 nm, a luminescence occurs where maximal intensity is at a wavelength of about 360 nm.
  • 3.3. The luminescence is dependent on (a) the excitation wavelength, (b) the side of the cocoon irradiated and (c) on the age of pupating larva.
  • 4.4. The cocoon cap displays electric conductance properties, in that the resistance to current is temperature dependent. Evidence is provided for a photoinduced electron-transfer system.
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5.
  • 1.1. Using SDS-PAGE and immunoblotting analyses with anti-sorbitol dehydeogenase (EC 1.1.1.14, SDH) serum, changes in amount of SDH protein were examined in diapause and non-diapause eggs of the silkworm, Bombyx mori.
  • 2.2. When diapause eggs were exposed to 5°C from 2 days after oviposition to break the diapause gradually, SDH protein appeared after 50-day chilling, and then the amount increased along with chilling period. This changing pattern paralleled that in SDH activity.
  • 3.3. In diapause eggs treated with HCl after chilling at 5°C for 30 days to break the diapause quickly, and non-diapause eggs, changing patterns in amount of SDH protein also paralleled those in SDH activity.
  • 4.4. These results showed that SDH activity was caused by biosynthesis of SDH protein, independent of diapause or non-diapause eggs.
  • 5.5. Occurrence of SDH correlates with the three developmental phases: diapause termination, embryonic growth, and larval differentiation. In larva, SDH was mainly localized in the fat-body.
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6.
  • 1.1. The ambient temperature of pipped eggs of the domestic fowl was reduced from 39 to 20°C for a period of 2 hr.
  • 2.2. In the majority of embryos the amplitude of respiration more than doubled during the first hour, and in each embryo the frequency fell to a minimum value by the end of cooling.
  • 3.3. When the eggs were rewarmed the respiratory frequency usually returned to normal within a period of 1 hr. Vocal activity was often stimulated and was accompanied by a marked increase in the amplitude of respiration.
  • 4.4. These results are discussed in relation to the development of thermoregulation, and are compared with results obtained elsewhere in a similar study on the quail.
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7.
  • 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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8.
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Highlights
  • •Proteome of mature boar spermatozoa from cauda epididymal and ejaculated sources were analyzed by iTRAQ-based LC-MS/MS.
  • •1,723 sperm proteins identified (974 of Sus scrofa taxonomy).
  • •1,602 sperm proteins quantified (960 of Sus scrofa taxonomy).
  • •32 Sus scrofa sperm proteins were differentially expressed among sperm sources.
  • •The proteome of boar spermatozoa is remodelled during ejaculation.
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9.
  • 1.1. A high percentage (53%) of isolated snails injected with prostate gland homogenates lay eggs.
  • 2.2. These egg masses consist of a few eggs which contain many nonviable oocytes.
  • 3.3. Preliminary experiments suggest that an egg-laying factor may be present in prostatic secretions.
  • 4.4. Snails bred in isolation from hatching, whether injected or not, occasionally lay viable eggs.
  • 5.5. This observation shows that self-fertilization or parthenogenesis is, in fact, possible in Helix aspersa Müller.
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10.
  • 1.1. The sperm-agglutinating factor (SAF) could be induced in the serum of male Nile tilapias, Oreochromis niloticus, by injection of allogeneic sperm.
  • 2.2. Only one class of molecules was demonstrated to be SAF in the serum.
  • 3.3. Analysis on purified SAF revealed it to be a tetrameric molecule of IgM with a mol. wt of 760kD.
  • 4.4. Cross reaction of the IgM with sperm of other teleost species suggests that sperm-specific surface antigens may be in evolution.
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11.
  • 1.1. Adult male Atremia salina L. were acclimated to five different oxygen concentrations and their respiration in response to environmental oxygen concentrations was determined.
  • 2.2. Anemia is a respiratory regulator over a wide range of partial O2 pressures. A critical oxygen tension exists and decreases with acclimation to lower pO2.
  • 3.3. Hypoxic conditions induce the production of hemoglobin III.
  • 4.4. Lactic acid is produced during anaerobiosis.
  • 5.5. Production of Hb III and lactic acid, being inversely proportional to the acclimation level, has to be considered as a long term or short term adaptation to hypoxic conditions.
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12.
  • 1.1. A method is described for the preparation of coupled mitochondria from hepatopancreas, mantle and adductor muscle of the sea mussle, Mytilus edulis.
  • 2.2. NADH is a non-penetrant, whereas succinate, glutamate and malate plus pyruvate have a clear stimulatory effect on respiration. Proline does not stimulate respiration of sea mussel mitochondria.
  • 3.3. No P/0 ratios could be calculated as after the addition of ADP the mitochondria remain in the active state (state III), even after enough oxygen is consumed for complete phosphorylation. The reason for this observation is discussed.
  • 4.4. Mitochondrial densities based on cytochrome b levels of two tissues of the mussel are compared to rat liver. Within the mussel the mantle contains twice the amount of cytochrome of adductor muscle.
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13.
  • 1.1. Inorganic ion content of developing follicles and of whole eggs and separated embryos and yolk sacs of the viviparous lizard, Sphenomorphus quoyii has been measured.
  • 2.2. There is a net increase in calcium, sodium and potassium in whole eggs during gestation. Magnesium and phosphorus content remains constant.
  • 3.3. The additional ions are incorporated into the developing embryo.
  • 4.4. Calcium content of the yolk is compared with that of the fowl and other species of reptile.
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14.
  • 1.1. Twenty-eight peptides were isolated from the egg jelly of sea urchins, Tripneustes gratilla, Pseudoboletia maculata, Strongylocentrotus nudus, Echinometra mathaei (type A and B) and Heterocentrotus mammillatus and their amino acid sequences were determined.
  • 2.2. Two of the peptides obtained from T. gratilla egg jelly possessed a bromophenylalanine (Br-Phe) residue in their sequences (Gly-(Br-Phe)-Asn-Leu-Asn-Gly-Gly-Gly-Val-Gly and Gly-(Br-Phe)-Asp-Leu-Asn-Gly-Gly-Gly-Val-Gly).
  • 3.3. All of the peptides elevated cyclic GMP concentrations in the spermatozoa of the respective sea urchin and caused a shift in the apparent mol. wt of a major sperm protein of the respective sea urchin.
  • 4.4. They stimulated respiration rates of the spermatozoa of Hemicentrotus pulcherrimus as well as their own species.
  • 5.5. One-half maximal concentrations of the peptides for respiratory stimulation of H. pulcherrimus spermatozoa were between 10−11 M and 10−9 M except a methionine-containing peptide which was about 10−7 M.
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15.
  • 1.1. The influence of temperature (14,19, 24°C), salinity (26,32, 38,44%.) and food type (artificial diets: Fryfood, Mytilus, Soya, Yeast, Spirulina) on the respiratory rate of Tisbe holothuriae has been studied.
  • 2.2. Oxygen consumption decreased with decreasing temperature, but with a greater rate at supra- or subnormal salinities.
  • 3.3. Multiple-regression analysis showed the quadratic effect of temperature and the linear effect of salinity to be the more important factors affecting respiration.
  • 4.4. The food type also seems to exert an important effect on oxygen consumption.
  • 5.5. A significant lowering of respiration was observed for all food tested when the animals were starved.
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16.
  • 1.1. Developing eggs of whitefish (Coregonus lavaretus L.) and vendace (Coregonus albula L.) were kept at 1–2°C and some eggs taken gradually up to 8°C to provoke mass hatching of embryos.
  • 2.2. Wet weight, dry matter and the contents of lipid, protein and ash were measured in fish during the course of experiment.
  • 3.3. Dry matter content decreased gradually in whitefish eggs from 15.64 to 11.95% during 1 month at 1–2°C, whereas vendace eggs showed only a slight decrease from 16.27 to 15.53%.
  • 4.4. In both species protein content decreased but lipid increased when approaching the natural time of hatching.
  • 5.5. During delayed hatching at low water temperatures protein contributes to catabolism, whereas lipid content decreased only in the later phase of the experiment.
  • 6.6. Larvae starved for 10 days after hatching lost increasing amounts of dry matter (from 26.1 to 50.3% of body weight) and protein (from 18.7 to 45.9% of body weight) as they remained longer in cold water as embryos.
  • 7.7. A correspondence was found between assessment of metabolic utilization of body stores based on chemical analysis of fish body and previous work on oxygen consumption and nitrogen excretion.
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17.
  • 1.1. We have characterized for the first time the major sperm-specific nuclear proteins (X, P1 and P2) of the tunicate Styela plicata. Both P1 and P2 have an amino acid composition that allows us to classify them as protamine-like proteins.
  • 2.2. The protein P1 of lower electrophoretic mobility has a trypsin-resistant core which is compositionally related to that of histones of the H1 family and to the PL-I protein found in the sperm of marine invertebrates. The evolutionary significance of this finding is discussed.
  • 3.3. In addition to P1 and P2, the sperm nucleus of S. plicata contains a protein X component which is also compositionally related to PL-I proteins from bivalve molluscs.
  • 4.4. Besides these sperm-specific proteins, a full complement of somatic-like histones, including a somatic-like histone H1, is also present. These histones represent only a small fraction of the total nuclear proteins of the sperm.
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18.
  • 1.1. Directly determined heats of embryogenesis were measured for Tribolium confusum eggs in a microcalorimeter fitted with air exchange, at 30°C.
  • 2.2. Parallel oxygen uptake measurements were made at 30°C, and combined with the heats to give the Calorific Equivalent of Oxygen Respiration quotient (the C.O.R.).
  • 3.3. The average C.O.R. values for the eggs in the 70 hr interval before hatch was 3.6 ± 0.2 kcal/l O2. This is somewhat lower than other (e.g. homoiothermic vertebrate) tissue. The C.O.R. increases to large values, in excess of 5 kcal/l O2 after hatch.
  • 4.4. The specific heat production during embryogenesis was 0.43 × 10−6cal/sec per mg live weight.
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19.
  • 1.1. Respiration rates of starved periwinkles, Liltorina littorea and Littorina obtusata, increased by 40–60% when fed their preferred algal food for 1 hr, or after having been exposed for the same period to an aqueous extract of the alga.
  • 2.2. The stimulus causing the rise in metabolic rate by algal extracts is therefore thought to be chemosensory in nature, and possibly composed primarily of dissolved free amino acids.
  • 3.3. The respiration rates of L. littorea responded only to the green alga Enteromorpha intestinalis while L. obtusata demonstrated an increase in respiration rates when fed the ubiquitous brown alga, Ascophyllum nodosum, and to a lesser degree to Enteromorpha.
  • 4.4. These results compare very well to postprandial increases in oxygen consumption demonstrated in vertebrates and marine bivalves where the components of specific dynamic action (SDA) are thought to be chiefly biosynthetic costs of digestion and assimilation.
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20.
  • 1.1. Two types of acid phosphatases from sea urchin eggs and embryos were studied in three Japanese species, Hemicentrotus pulcherrimus, Anthocidaris crassispina and Pseudocentrotus depressus.
  • 2.2. Acid phosphatase type 1, designated AcP-1, hydrolysed only flavin mononucleotide besides p-nitrophenylphosphate. The activity of AcP-1 was not inhibited by NaF and tartrate. This enzyme showed molecular weight between 14,000 and 16,000 by gel filtration through Sephadex G-75.
  • 3.3. The higher molecular weight type of acid phosphatase, designated AcP-2, showed relatively high substrate specificity toward ADP and ATP. Molecular weight of AcP-2 ranged from 42,000 to 48,000 by gel filtration through Sephadex G-100.
  • 4.4. Some properties of AcP-2 from Sphaerechinus granularis embryos are also described.
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