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1.
  • 1.1. Cuticular hydrocarbons of two clones of Rhopalosiphum maidis, two of R. padi, one of R. insertum, and one of Schizaphis graminum were identified as n-alkanes, monomethylalkanes and dimethylalkanes.
  • 2.2. No qualitative differences in hydrocarbon content were apparent among the six aphid populations studied; however, hydrocarbon profiles were discriminatory.
  • 3.3. Discriminant analysis of the proportions of the cuticular hydrocarbons selected 29 hydrocarbon components that provided discrimination among populations except for the two R. padi clones which were indistinguishable.
  • 4.4. Scanning electron micrographs showed very clear differences in the cuticular surface patterns among the three Rhopalosiphum species.
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2.
  • 1.1. Conjugation of Tetrahymena enhanced the incorporation of glycine into the nuclear fraction by 500%.
  • 2.2. Incorporation of glycine into the microsomal supernatant was augmented by almost 500% by conjugation.
  • 3.3. Mitochondrial incorporation was stimulated nearly 3-fold in the conjugating strains while the incorporation of glycine into the microsomes was enhanced approximately 2.5 times.
  • 4.4. In the whole cell, glycine incorporation was increased nearly 2-fold by conjugation.
  • 5.5. Strong nuclear involvement was indicated by elevated metabolic activity and incorporation of glycine into RNA and DNA.
  • 6.6. Stimulation of the metabolism of Tetrahymena by cell communication suggests that the contents of a cell can have a synergistic effect on another cell.
  • 7.7. Augmentation of the biosynthetic capacities of cells by fusion is a demonstration of the dominant role of the cell membrane in the regulation and control of cells.
  • 8.8. Enhancement of biosynthesis of nuclear proteins in conjugating strains of cells indicates that fusion gives rise to the synthesis of new protein from previously existing protein or protein procursors.
  • 9.9. The specific activities of the subcellular fractions after the incorporation of glycine into 2 separated starved strains of Tetrahymena followed the usual pattern of nucleus less than whole cells, whole cells less than mitochondria, mitochondria less than microsomes, but with the microsomal supernatant being much greater than that of the microsomes.
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3.
The major pectoral muscles (musculus pectoralis superficialis) of two species of bats (Miniopterus schreibersi fuliginosus and Rhinolophus ferrumequinum nippon) were studied by electron microscope and quantitative determination of myoglobin were carried out.
  • 1.2. In the pectoral muscles of both species, numerous mitochondria and lipid droplets occur between myofibrils.
  • 2.3. The average myoglobin concentration is 5.58 mg/g in M. s. fuliginosus and 1.83mg/g in R. f. nippon.
  • 3.4. It is suggested that these differences are related to the physiological properties of the muscles needed for different types of flight.
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4.
  • 1.1. The organic composition of the body tissues of eight species of deep-sea aspidochirotid holothurian, collected between 500 and 4100m depth in the NE Atlantic Ocean, was obtained by the biochemical analysis of protein, lipid, carbohydrate and % ash.
  • 2.2. The major organic class was protein with soluble lipid the major soluble fraction in the ovary. Carbohydrate values were consistently low.
  • 3.3. The calorific value was significantly higher in the ovary than in the other tissues.
  • 4.4. The total body calorific content for two selected species, Benthothuria funebris and Mesothuria lactea, was 25.62 and 26.24J/mg ash-free dry weight (AFDW).
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5.
  • 1.1. Xanthopterin inhibited proliferation of primary renal proximal tubule cells (RPTC) and LLC-PK1 cells while in a growth phase but when incubated at confluence the cells were relatively insensitive.
  • 2.2. The growth of malignant human prostate PC-3 cells was also inhibited by xanthopterin in a concentration and time dependent manner.
  • 3.3. Dunning R3327 AT-3 rat prostate tumor cells which were exposed to xanthopterin in vitro before their in vivo inoculation resulted in smaller tumours while in vivo administration of xanthopterin following implantation also resulted in smaller tumors.
  • 4.4. Xanthopterin exerts differential effects on cell growth dependent upon the cell origin and their state of proliferation.
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6.
  • 1.1. Ovaries of Therobia domestica, dissected from inseminated females and incubated with tritiated amino acids, synthesize labeled proteins, the major fraction of which is indistinguishable from the major vitellogenin secreted by the fat body, when considering the electrophoretic mobility, the polypeptide composition and the immunoreactivity.
  • 2.2. Peptide mapping, using two different proteases, shows a striking structural similarity between the proteins of both origins and reveals interrelationships between their subunits.
  • 3.3. The ovary synthesizes the 210–212 kD precursors of the major vitellogenin, as does the fat body, and processes them intensively into smaller subunits (176–182, 57 and 46 kD). The follicle cells are tentatively nominated for both roles.
  • 4.4. The quantitative contribution of the two ovaries to the vitellogenin pool was found to be much higher than that of the fat body.
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7.
  • 1.1. The major form of acetylcholinesterase (AChE) from Lygus hesperus demonstrated a greater affinity to selected substrates than unresolved AChE.
  • 2.2. The turnover numbers of the native AChE were 7000 min−1 for acetylthiocoline, 4800 for acetyl-(β-methyl) thiocholine, 3000 for propionylthiocholine, and 390 for S-butyrylthiocholine.
  • 3.3. Each molecule of the major form had two active sites and each subunit had one active site.
  • 4.4. Paraoxon or dichlorvos had a higher affinity to the major AChE form than to the unresolved AChE, resulting in a higher potency for the inhibition.
  • 5.5. Some references of comparison are also made with AChE from other animal species.
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8.
  • 1.1. A single neuron is found in each buccal ganglion of the giant garden slug, Limax maximus, which is autoactive and has an axon in both the ipsilateral and contralateral salivary nerve.
  • 2.2. This neuron, the bilateral salivary neuron (BSN), is a slow bursting neuron and is presynaptic to some of the secretory acinar cells of the salivary gland.
  • 3.3. Increases in BSN action potential frequency and saliva flow during the generation of feeding motor program are shown, as is the relationship of BSN activity to that of other salivary neurons.
  • 4.4. BSN is affected synaptically by the serotonergic metacerebral giant cell.
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9.
  • 1.1. Blood proteins were studied by polyacrylamide disc gel electrophoresis in three species of prairie dogs, Cynomys gunnisoni, C. leucurus, and C. ludovicianus.
  • 2.2. The sera were separated into 13–15 fractions and the three species could be distinguished by both qualitative and quantitative differences in their serum patterns.
  • 3.3. Qualitatively, variations in the occurrence and number of slow albumin fractions are diagnostic at the species leel.
  • 4.4. Quantitative differences were most apparent in variation in the mobility of the major albumin fraction and the transferrin fraction.
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10.
  • 1.1. There is no uniform pattern of porphyrin synthesis by whole blood and haemolysates, between the different mammalian species studied.
  • 2.2. Coproporphyrin, is the dominant porphyrin synthesised by intact red cells.
  • 3.3. Uroporphyrin synthesis increases significantly in the majority of species when the cells are haemolysed.
  • 4.4. In the mouse large amounts of protoporphyrin are synthesised by intact red cells which increases further on haemolysis.
  • 5.5. The low porphyrin synthesising capacity of cow and sheep red cells is not due to any rate-limiting activity of the enzyme ALA-dehydratase.
  • 6.6. The dog has a pattern of porphyrin synthesis and excretion similar to that found in the rabbit, and the possibility exists, that a similar energy-dependent carrier mechanism for movement of uroporphyrin and coproporphyrin across red cell membranes found in the rabbit may be present in this species.
  • 7.7. The findings may be of significance in the interpretation of porphyrin excretion patterns in experimental porphyria.
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11.
  • 1.1. The hemoglobins of Leporinus friderici were separated by liquid chromatography on DEAE-Sepharose in order to isolate the two major electrophoretic components.
  • 2.2. The chromatographic fraction I (electrophoretically slow anodic) showed no Bohr effect and no nucleoside triphosphate modulation.
  • 3.3. The chromatographic fraction III (electrophoretically fast anodic) showed a normal Bohr effect and addition of nucleoside triphosphate decreased oxygen affinity but did not alter the Bohr effect.
  • 4.4. The whole hemolysate showed a normal Bohr effect and phosphate modulation altered both Bohr effect and oxygen affinity.
  • 5.5. No or little difference between the effect of adenosine or guanosine triphosphates on hemoglobin function was observed.
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12.
  • 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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13.
  • 1.1. The proteoglycan peak from anion exchange chromatography of an extract of bovine aorta was digested with chondroitinase ABC. The residual heparan sulphate proteoglycans were further purified by chromatography on Sepharose CL4B and DEAE-Sephacel to yield two species, of high and low charge density.
  • 2.2. Higher molecular weight material had a higher proportion of high charge density proteoglycan, while the lower molecular weight species had a higher proportion of low charge density heparan sulphate proteoglycan.
  • 3.3. The two species shared epitopes as they both reacted with an antibody to heparan sulphate proteoglycan from bovine glomerular basement membrane.
  • 4.4. On electron microscopy, both high and low charge density proteoglycans were visualized as ‘tadpole-like’ molecules, which showed a tendency to aggregate via their globular heads.
  • 5.5. Bovine aortic smooth muscle cells were cultured in the presence of [35S]sulphate and [3H]glucosamine. Proteoglycans were isolated from medium and cell layer extract by the methods outlined above.
  • 6.6. The major HSPG species isolated from medium were significantly larger than those from cell layer and displayed substantial heterogeneity in both size of HS chain after papain digestion and size of protein core after heparitinase digestion. 7. The major cell layer species yielded two HS species of widely differing mol. wt after papain digestion, and a very small protein core after heparitinase digestion. Therefore cell layer-associated HSPGs show a good deal more homogeneity than those found in the medium.
  • 7.8. Further ion-exchange chromatography after digestion with chondroitinase ABC revealed HSPG species of lower charge density, possibly derived from a hybrid chondroitin sulphate-dermatan sulphate proteoglycan (CS/DSPG) after removal of the CS/DS chains.
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14.
  • 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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15.
  • 1.1. A lipoxygenase preparation was obtained from Thermoactinomyces vulgaris and was purified by affinity chromatography on a linoleyl aminoethyl sepharose column.
  • 2.2. Two active fractions were obtained.
  • 3.3. The fraction obtained by elution with 100 mM borate buffer pH 9.0 was used in the subsequent work.
  • 4.4. Th. vulgaris lipoxygenase oxidized linoleic acid into two products: 13-HPOD and 9-HPOD at a ratio of 44 to 56, respectively.
  • 5.5. The identification and characterization of the isomers was done by HPLC, I.R. and mass spectrometry.
  • 6.6. When arachidonic acid was used as substrate, 15-HPETE and 15-HETE were found to be the main enzymatic products.
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16.
  • 1.1. Blood indices were measured in 27 species of lizard from Chile and Argentina occurring at different altitudes ranging from sea-level up to 4600 m.
  • 2.2. Contrary to amphibians, none of the hematological values of these lizards, such as hematocrit, hemoglobin concentration, red cell count, mean cell volume, mean cell hemoglobin and mean cell hemoglobin concentration, were found to be correlated with their altitudinal distribution.
  • 3.3. Intrageneric comparison of blood values in Liolaemus lizards (seven highland species living above 3000m and 12 lowland species) showed a similar degree of independence from their altitudinal site of capture or from their upper limit of distribution.
  • 4.4. As reported for other vertebrate taxa, an inverse correlation between size and number of red blood cells was also found in the studied reptiles.
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17.
  • 1.1. The possibility of natural hybridization between Etheostoma spectrabile and E. caeruleum at two Ohio locations was investigated using starch gel electrophoresis. Fifty-six fish, including eight which were morphologically intermediate, were analyzed at 26 presumptive genetic loci.
  • 2.2. Although key morphological characteristics indicated that both species occurred in both streams, electrophoretic data demonstrated the presence of only E. caeruleum in one stream.
  • 3.3. No biochemical evidence for hybridization between E. spectabile and E. caeruleum was found.
  • 4.4. Etheostoma caeruleum appears to be morphologically plastic and the key taxonomic characteristics used for its field identification may not be valid.
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18.
  • 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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19.
  • 1.1. Nematocyst structural proteins (NSP) from the sea anemones Aiptasia pallida and Metridium senile and the siphonophore Physalia physalis are primarily low molecular weight collagens linked by disulfide bonds.
  • 2.2. NSP patterns resolved by SDS-PAGE revealed a common, major collagen species (40 kDa) in each nematocyst type, together with other collagens and non-thiol-containing proteins.
  • 3.3. For each cnidarian, NSP glycosylation profiles were significantly different.
  • 4.4. Monoclonal antibodies against Aiptasia NSP demonstrated a differential distribution between capsule wall and thread.
  • 5.5. NSP differences would account for the diversity of morphologic and functional types.
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20.
  • 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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