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1.
  • 1.1. Polyamines were extracted from the guts and ovaries of the sea urchin Anthocidoris crassispina, and the guts and flesh of the sea cucumber Stichopus japonicus and the sea squirt Halocynthia roretzi, the oyster Crassostrea gigas and the short-necked clam Tapes philippinarum, and analyzed by ion-exchange high-performance liquid chromatography and gas chromatography-mass spectrometry.
  • 2.2. Norspermidine and norspermine as well as putrescine, cadaverine, spermidine, spermine and agmatine were the ubiquitous polyamines in these invertebrates. These results suggest the widespread distribution of norspermidine and norspermine in invertebrates.
  • 3.3. Thermopentamine, thermohexamine and homothermohexamine were found in the sea urchin. This in the first report on the occurence of thermopentamine and hexaamine in invertebrates.
  • 4.4. Homospermidine, canavalmine, aminopropylhomospermidine, homospermine, caldopentamine, homocaldopentamine and aminopropylcanavalmine were found in the sea cucumber. Homospermidine, aminopropylhomospermidine and homospermine were found in the squirt. This is the first report on the occurence of canavalmine, aminopropylhomospermidine, homospermine, homocaldopentamine and aminopropylcanavalmine in invertebrates.
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2.
  • 1.1. Tissue-specific abundance of the capped small RNAs in the silkmoth Bombyx mori was compared using preparative immunoprecipitation with anti-trimethylguanosine antibody.
  • 2.2. The yields of total capped small RNAs from larval posterior silk gland, 1. early, 2. late in the fifth-instar, and 3. immortal ovarian-derived cells in culture, were determined to be 187, 50 and 218 ng, respectively, per mg of total cellular RNA.
  • 3.3. Separation of immunoprecipitated RNAs by polycrylamide gel electrophoresis, followed by densitometric analysis of the bands, allowed the quantitation of individual capped molecules.
  • 4.4. This analysis revealed tissue-specific patterns.
  • 5.5.|The data indicate that the total abundance of capped small RNAs in Bombyx is highest in rapidly-dividing cells.
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3.
4.
  • 1.1. Partially purified rat liver ornithine decarboxylase is inhibited by several diamines including putrescine, 1,3-diaminopropane, cadaverine and p-phenylenediamine.
  • 2.2. The inhibition is dependent on pH, being strong at pH above 8 and negligible below pH 6.5.
  • 3.3. The kinetic study of the inhibition showed that while the aromatic diamine behaved as a simple competitive inhibitor, the aliphatic diamines presented a more complex pattern of inhibition in which two molecules of inhibitor might bind to the enzyme active site.
  • 4.4. The KI values for the different inhibitors were calculated and the degree of affinity for the enzyme was p-phenylenediamine > putrescine > cadaverine > 1,3-diaminopropane.
  • 5.5. A molecular mechanism explaining how one or two molecules of inhibitor can bind to the enzyme is proposed.
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5.
  • 1.1. The protein composition of Bothrops jararaca venom and venom gland was analyzed through SDS-PAGE, after isoproterenol (IPR) treatment.
  • 2.2. Some proteins (47, 48, 57 and 72 kDa) were detected in the gland homogenate from the control but not from the IPR-treated samples.
  • 3.3. Three proteins (26.5, 44.5 and 53 kDa) were detected in the venom gland from IPR-treated snakes but not from the venom gland from the control.
  • 4.4. In the venom samples proteins of 41 and 74 kDa were detected only in the IPR treated samples, while proteins of 17 and 28 kDa were detected only in the control.
  • 5.5. The biological activity of the venom did not change with IPR treatment.
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6.
  • 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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7.
  • 1.1. Digestive gland and mantle fatty acids were studied in spring and summer in the bivalve Macoma balthica off the southern coast of Finland. The presence of lipids was also examined histochemically in various clam tissues.
  • 2.2. the neutral lipid content of the digestive gland increased ca 4.5-fold during the annual growth period.
  • 3.3. Neutral lipid fatty acids of the digestive gland, of which palmitoleic, eicosapentaenoic and palmitic acids were predominant, were clearly distinguished from phospho- and glycolipid fatty acids.
  • 4.4. The degree of unsaturation of phospholipid fatty acids was higher in the cold season both in the digestive gland and mantle, mainly due to the titer of eicosapentaenoic acid.
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8.
  • 1.1. Phosphatase acid (PhA) activity in the digestive gland (hepatopancreas) of the common garden snail Helix aspersa has been investigated using cytochemical methods.
  • 2.2. All the cells composing this gland show PhA activity, the distribution pattern differing according to the cell type.
  • 3.3. The digestive cells show the most widely distributed reaction product (brush border, phagolysosomes, multivesicular bodies and autophagic vacuoles).
  • 4.4. In the excretory cells this activity appears in large sacs, while in the calcium cells the reaction product is abundant in the calcium granules.
  • 5.5. Cellular digestion processes performed by each of these cell types is discussed together with their role in the detoxification of heavy elements derived from the environment.
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9.
  • 1.1. The glutathione S-transferases of Megachile rotundata (Fab.) were characterized eletrophoretically and spectrophotometrically.
  • 2.2. Differences were found between sexes with respect to number of isozymes and activity with age.
  • 3.3. Inhibition patterns of chalcone, seven of its synthetic derivatives, flavone, quercetin, and tridiphanediol differed with respect to sex and substrate.
  • 4.4. Comparisons are made with the honey bee, Apis mellifera L.
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10.
  • 1.I. Serum lipoproteins play an important role in the in vivo transport of several porphyrinoid derivatives having a moderate or high degree of hydrophobicity.
  • 2.2. There appears to exist a correlation between the extent of photosensitizer association with low-density lipoproteins (LDL) and the efficiency of tumour targeting by some classes of photosensitizers, such as differently sulphonated porphyrins and phthalocyanines, haematoporphyrin dialkylethers and unsubstituted phthalocyanines and naphthalocyanines.
  • 3.3. In all cases, LDL-carried photosensitizers are preferentially released to malignant cells; hence, direct cell damage appears to be the major determinant of tumour damage consequent to photodynamic therapy.
  • 4.4. Present evidence suggests that the LDL-associated photosensitizer is accumulated by tumour cells largely via a receptor-mediated endocytotic process.
  • 5.5. Thus, the use of delivery systems for orientating a systemically injected photosensitizer towards lipoproteins has been explored; promising results have been obtained by incorporation of the dye into liposomal vesicles, oil emulsions or inclusion complexes, as well as by precomplexation of the dye with LDL.
  • 6.6. Moreover, a suitable choice of the chemical constituents of the delivery system and the experimental conditions allows one to modulate the photosensitizer distribution among the different lipoproteins.
  • 7.7. The occurrence of tumour-targeting strategies other than the LDL pathway is briefly discussed.
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11.
  • 1.1. Recently we described the isolation of the β-interferon receptor [Zhang et al. (1986) J. biol. Chem. 261, 8017–8021]. A highly purified product was obtained but in low quantities.
  • 2.2. The use ofbiotinylated β-interferon as a ligand represents an alternate approach to receptor isolation.
  • 3.3. We have prepared and characterized the derivatives N-(biotinyl)- and N-(biotinyl-ϵ-aminocaproyl)-recombinant human [Ser17-interferon β (B- and BC-recHulFNβ).
  • 4.4. Biotin incorporation does not result in any loss of antiviral activity, demonstrating the recognition of the derivative by the cell receptor.
  • 5.5. The biotinylated recHuIFNβ binds specifically and reversibly to succinoylavidin or guanidine thiocyanate-stripped succinoylavidin linked to a Sepharose matrix.
  • 6.6. Comparison of the competition curves obtained with [14C]biotin and [3H]biotinyl recHuIFN, in the presence of increasing concentrations of biotin suggests that the IFN moiety of the derivative has little effect on the affinity of biotin for avidin.
  • 7.7. Biotinylated recHuIFNβ derivatives represent useful probes for the β-IFN receptor.
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12.
  • 1.1. The Dufour gland secretions of Formica fusca consist mainly of saturated straight and branched chain hydrocarbons (C9–C19), one unsaturated hydrocarbon (C13) and two sesquiterpenoids, farnesene and homofarnesene.
  • 2.2. In F. lemani, the Dufour gland contains branched, saturated and unsaturated hydrocarbons (C9–C19) and two farnesenes.
  • 3.3. The two species were distinguished chiefly by the presence of a relatively large proportion of farnesene in F. fusca, with very little homofarnesene and by contrast, little farnesene but much more homofarnesene in F. lemani.
  • 4.4. The contents of the Dufour gland can be used as a chemotaxonomic clue to distinguish between the species.
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13.
  • 1.1. The sterol composition of the digestive gland and the gonad of Sepia officinalis L. was investigated by GC and GC-MS.
  • 2.2. The same sterols were recognized in both organs, cholesterol being the major component of the sterol mixtures. However, quantitative differences appeared between the sterol composition of the digestive gland and the gonad.
  • 3.3. The sterol mixtures of the digestive gland and the gonad of immature and mature females and males of various origins were compared. Quantitative changes in the sterol composition of the gonad were related to sexual maturity whereas the sterol composition of the digestive gland appeared linked to the diet.
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14.
  • 1.1. Blood metabolite levels were assayed in Carcinus maenas as an indicator of the functioning of the hyperglycemic hormone, HGH, secreted by the crab's eyestalk neuroendocrine tissue.
  • 2.2. Bilateral eyestalk ablation eventually resulted in a hypoglycemic response after 2–3 days.
  • 3.3. Bilateral optic nerve section produced a significant, long-term hypoglycemic response suggesting that release of HGH from the eyestalk sinus gland is controlled, via a promotive neural pathway, by the CNS and probably by the cerebral ganglia.
  • 4.4. Injection of eyestalk extract into operated crabs consistently produced significant, short-term hyperglycemia.
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15.
  • 1.1. Sterols were identified from eight isolates of five species in the Chromophycota that were cultured axenically and harvested in the stationary phase.
  • 2.2. Analyses were performed on four strains from the Prymnesiophyceae, two strains from the Cryptophyceae and one from the Bacillariophyceae. Most strains examined contained only one major sterol, 24-methyl-22-dehydrocholesterol.
  • 3.3. Analysis by capillary GC, HPLC, and in one instance NMR, showed that the two strains provisionally identified as Isochrysis contained brassicasterol (24β-methyl-22-dehydrocholesterol); whereas, all other species examined contained primarily epibrassicasterol (24α-methyl-22-dehydrocholesterol).
  • 4.4. Stigmasterol (24α-ethyl-22-dehydrocholesterol) accompanied epibrassicasterol in Pleurochrysis carterae.
  • 5.5. Analyses of C-24 alkyl isomers in these algae may provide useful information concerning their taxonomic placement.
  • 6.6. The occurrence of both isomers of 24-methyl-22-dehydrocholesterol in oysters is explained by the occurrence of both isomers among algae which are probably dietary sources for oysters.
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16.
  • 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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17.
  • 1.1. Glycogen and galactogen contents of the albumen gland of the freshwater snail Lymnaea stagnalis were determined under different conditions, known to influence these polysaccharides viz egg laying, photoperiod and starvation.
  • 2.2. After oviposition, the galactogen content is restored within 32 hr, whereas glycogen remains constant during this period. Short-day photoperiods favour accumulation, long-day photoperiods induce depletion of glycogen. In contrast, the galactogen content is not affected by the photoperiod.
  • 3.3. Since glycogen and galactogen are present in the same cells of the albumen gland, the independent variation of these polysaccharides would imply the presence of separate intracellular regulation mechanisms.
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18.
  • 1.1. The postmitochondrial fraction of the marine mussel Mytilus galloprovincialis digestive gland activates selectively precarcinogenic aromatic amines, but not precarcinogenic benzo(a]pyrene, to Salmonella typhimurium TA 98 mutagens.
  • 2.2. This activation potential is NADPH-dependent, is not inducible by exposure to Diesel 2 oil and a polluted environment, and is inhibited by methimazole.
  • 3.3. The characteristics of this activation potential are consistent with the recent finding of the presence of FAD-containing-, and lack ofcytochrome P-450 dependent-, monooxygenase activity in Mytilus edulis.
  • 4.4. The presence of such selective potential in marine invertebrate(s) may bring new insight into our understanding of the fate and the effects of carcinogens in the marine environment.
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19.
  • 1.1. Myosin light chains and parvalbumins have been compared in several trunk and head muscles from small and large size barbels (Barbus barbus) living in river or reared in hatchery.
  • 2.2. These proteins isolated from white, red and ventricle fibres exhibit identical electrophoretic characteristics in the four batches.
  • 3.3. The slow fibre content and the parvalbumin distribution are generally similar in river and hatchery barbels of the same size but differ between small and large barbels within a population.
  • 4.4. Alterations of the mode of fertilization and breeding conditions do not modify the differentiation of myosin and parvalbumins in barbels.
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20.
  • 1.1. Crude digestive gland extract (DGE) of 5 species of marine bivalve mollusc had glycosidase activity against lipopolysaccharides (LPS) of gram-negative bacteria.
  • 2.2. Most of these extracts, after ammonium sulphate precipitation, had higher glycosidase activity than commercial Helix pomatia gut juice.
  • 3.3. Inorganic phosphate was also released from LPS by the various DGE but the lipid moiety of LPS appeared to be resistant to attack except by a DGE from Cerastoderma edule, which released small quantities of only non-hydroxylated fatty acids.
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