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1.
  • 1.1. Biochemical analysis of the different segments of the oviduct in the ovoviviparous salamander, Salamandra salamandra, reveals the monosaccharides glucose, galactose, fucose, mannose, ribose and the hexosamines glucosamine and mannosamine.
  • 2.2. In segment 1 (pars recta) ribose and mannose are absent, and in segments 2 (p. convoluta I) and 5 (p. convoluta IV, uterus) mannose is not detectable; fucose is absent in the uterus. Segments 3 (p. convoluta II) and 4 (p. convoluta II) contain all sugars identified.
  • 3.3. The main hexoses present in the glandular segments are galactose, fucose and glucose.
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2.
  • 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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3.
  • 1.1. The concentrations of free glycerol, inositol and trehalose in five species of nematodes were determined. Analyses of total inositol content were also made.
  • 2.2. Significant differences in free and bound sugar levels were found between the two good anhydrobiotes Anguina tritici and Ditylenchus dipsaci and the three poor survivors Pangrellus redivivus, D. myceliophagous and Turbatrix aceti.
  • 3.3. Highest trehalose contents were found in desiccated A. tritici and D. dipsaci, but glycerol levels were low.
  • 4.4. P. redivivus and T. aceti contained high concentrations of free glycerol.
  • 5.5. Desiccated A. tritici larvae contained more free and bound inositol than all other species studied, but desiccated D. dipsaci larvae had higher levels of bound inositol than P. redivivus, D. myceliophagous and T. aceti.
  • 6.6. Dramatic reductions in inositol and trehalose contents were found in revived A. tritici larvae and freshly extracted D. dipsaci larvae. This was accompanied by an increase in glycerol content.
  • 7.7. The results are discussed in relation to the possible biochemical adaptations employed by anhydrobiotes during desiccation.
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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. The incorporation of myo-[2-3H]inositol into phosphatidylinositols was unmodified in brain cortex miniprisms from convulsant rats.
  • 2.2. However, the incorporation had increased by 300–400% in non convulsant rats which had received the same amount of lindane at a lower concentration.
  • 3.3. This result suggests that phosphatidylinositols are implicated in the convulsion syndrome.
  • 4.4. Experiments with lindane added in vitro were performed with both subchronically lindane intoxicated and untreated rats.
  • 5.5. The results show an interesting lack of parallelism.
  • 6.6. This might indicate the development of some resistance to the effects of lindane, possibly as the result of complex compensatory changes in inositol lipid biosynthesis.
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6.
  • 1.1. A pulse-chase autoradiographic study of incorporation of 3H-leucine into body-wall, digestive and reproductive tissue of virgin adult Panagrellus redivivus demonstrates both tissue and sex-specific patterns of protein biosynthesis and turnover.
  • 2.2. Female body wall has a higher rate of protein synthesis and turnover than male body wall.
  • 3.3. Uptake of leucine into macromolecule in the digestive tissue is more rapid in males than females, as is the rate of turnover.
  • 4.4. The ovary is more rapidly labelled than the testis, with a much more rapid turnover rate.
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7.
  • 1.1. myo-Inositol decreases the synthesis of phosphatidylglycerol by type II cells isolated from fetal rat lung. Inositol addition also increases the synthesized amount of surfactant phosphatidylinositol. These observations indicate that at least part of the decreasing effect of inositol on phosphatidylglycerol formation is the result of competition between phosphatidylglycerol and phosphatidylinositol synthesis for a common pool of CDPdiacylglycerol.
  • 2.2. Studies on the subcellular localization of enzymes measured under optimal conditions suggested that the enzymic activity required for the formation of phosphatidylglycerol is located mainly in the mitochondria, but most likely also for a small part in the endoplasmic reticulum, while the enzymic activity required for phosphatidylinositol formation is located in the endoplasmic reticulum.
  • 3.3. Inositol was found to inhibit glycerolphosphate phosphatidyltransferase in the microsomal fraction but not in the mitochondrial fraction derived from the type II cells, indicating that the competition between phosphatidylglycerol and phosphatidylinositol synthesis for CDPdiacylglycerol takes place in the endoplasmic reticulum.
  • 4.4. This latter observation together with the observation of a switch-over from surfactant phosphatidylinositol to phosphatidylglycerol production around term indicate that the endoplasmic reticulum is the intracellular site of surfactant phosphatidylglycerol production.
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8.
  • 1.1. An SDS-PAGE study of the qualitative and quantitative differences in protein bands from haemolymph and ovaries of Spilostethus pandurus females treated with JH or chemically allatectomized with precocene II, has been done.
  • 2.2. The SDS-PAGE study of haemolymph revealed the occurrence of three female-specific proteins. In the ovary appeared three protein fractions (A, Band C) with mol. wts similar to those from haemolymph.
  • 3.3. The three female-specific proteins from the haemolymph, and the ovary bands B,C and D were absent in the samples from PII-treated females.
  • 4.4. JH accelerates ovary growth and the relative amounts of bands B, C and D were in relation to the physiological stage of the considered ovaries.
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9.
  • 1.1. Signal transduction in response to platelet-derived growth factor (PDGF)-BB and bradykinin (BK) have been examined by measuring inositol polyphosphate formation in NIH3T3 fibrobalst and v-Ki-ras -transformed NIH3T3 fibroblast (DT).
  • 2.2. The PDGF-induced inositol polyphosphate formation in NIH3T3 was greater than that in DT cells, in which autophosphorylation of PDGF receptor and tyrosine phosphorylation of phospholipase C (PLC)-γ 1 were suppressed when examined by immunoblotting with anti-phosphotyrosine antibody.
  • 3.3. On the other hand, BK-stimulation produced a much higher level of inositol polyphosphate in DT cells which have a greater number of BK receptors.
  • 4.4. These results indicate that in Ki-ras transformed cells the decrease (caused by PDGF) and the increase (caused by BK) in phosphoinositide hydrolysis are due to the defective autophosphorylation of PDGF receptors leading to a reduction in PLC-γ 1 tyrosine phosphorylation and the overexpression of BK receptors, respectively.
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10.
  • 1.1. The influences of age (5, 13 and 25-month-old rats), overload as obtained by denervation of synergists, and training on the metabolic capacity, relative muscle cross-sectional area occupied by each fibre type, capillarization and fatigue resistance of the rat m. plantaris were investigated.
  • 2.2. Creatine kinase, phosphorylase and citrate synthase activities were lower in muscles of 25 than in those of 13-month-old rats (P < 0.001).
  • 3.3. Overload resulted in an increased relative area of type I and II a fibres at all ages (P = 0.001).
  • 4.4. Capillary density decreased with overload and increasing age (P < 0.001).
  • 5.5. Fatigue resistance was higher in muscles of 13 than in those of 5-month-old rats (P < 0.05), and increased with overload (P < 0.05) at all ages.
  • 6.6. Fatigue resistance of the whole muscle was not closely related to its oxidative capacity in contrast to what is generally found for single fibres or motor units.
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11.
  • 1.1. Heliothis zea (Boddie) larvae infected with irridescent virus (IV) showed rapid cell dissolution in the fat bodies.
  • 2.2. Fatty acid accumulation in healthy H. zea was significantly greater (P < 0.001) than in IV-infected larvae.
  • 3.3. Healthy and IV-infected larvae accumulated glycogen at a rate of 3.86 cal and 0.19 cal/day/insect, respectively.
  • 4.4. Total protein of healthy and IV-infected larvae showed no significant difference with time.
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12.
  • 1.1. Yolk proteins were isolated from ovaries of the shrimp Penaeus vannamei and used as an antigen for antibody production in rabbits.
  • 2.2. Protein synthesis was measured for both the hepatopancreas and the ovary in vitro, and proteins present in both tissues were immunoreactive with the antibodies.
  • 3.3. Extracts of shrimp eyestalks inhibited in vitro protein synthesis by both tissues. The inhibitory factor from the eyestalks was heat stable and had a molecular weight of 3300 daltons.
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13.
  • 1.1. The mean annual Zn content of the sperm storage organs (uterus and epididymis) in Myotis velifer and M. lucifugus is two to three times higher than in corresponding tissues of other mammals.
  • 2.2. The content of Zn in the sperm storage organs and male accessory glands has an annual cyclic pattern. Significant increases are recorded at prehibernation insemination (September) and posthibernation conception (April/May).
  • 3.3. Zinc is present in the storage organs of bats throughout the spermatozoa storage phase of the reproductive cycle.
  • 4.4. Zinc, due to its regulatory effects on spermatozoa (maturation, metabolism, motility) may be important in sperm storage in hibernating bats.
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14.
  • 1.1. Eyestalk unablated and unilaterally ablated Penaeus monodon juveniles had survival rates after 5 months of 75–72.5 and 67.5–60%, respectively.
  • 2.2. Unilaterally ablated shrimps had significantly higher (P < 0.05) growth rate than unablated shrimps.
  • 3.3. Eyestalk-ablatement resulted in a decrease in the haemolymph sodium concentration and an increase in the potassium and calcium concentration of shrimps.
  • 4.4. The osmolarity of haemolymph and total protein concentration of unablated shrimps were demonstrated to be higher than those of unilaterally ablated shrimps.
  • 5.5. The eyestalk-ablated shrimps possess higher total ATPase and Na+,K+-ATPase activities in the gill than those of unablated shrimps.
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15.
  • 1.1. In vitro yolk synthesis was measured in fragments of the ovary of developing shrimp, Penaeus vannamei.
  • 2.2. Progesterone and estradiol stimulated yolk synthesis in vitro, while ecdysterone, testosterone and estrogen had no effect.
  • 3.3. A peptide factor from the eyestalks of crayfish stimulated yolk synthesis in vitro. A peptide factor from shrimp eyestalks inhibited yolk synthesis in vitro.
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16.
  • 1.1. The effects of different amounts of passive stretch per day and number of days of stretch on muscle hypertrophy in the chicken patagialis (PAT) muscle were determined.
  • 2.2. Stretch for 24 hr per day (h/d) resulted in a more rapid hypertrophy both on a wet and dry tissue basis (P < 0.001) than stretch for 4 h/d.
  • 3.3. Stretch increased PAT weight 43% and 25% in 24 h/d and 4 h/d treatments, respectively, after 10 days of stretch, but by day 25 of stretch there was no difference between treatments.
  • 4.4. In a second experiment, the PAT muscle was hypertrophied and then the effects of intermittent stretch (4 h/d) on regression of hypertrophy (muscle atrophy) were investigated.
  • 5.5. Intermittent stretch (4 h/d) for 5 and 10 d significantly (P < 0.001) inhibited regression of hypertrophied muscle.
  • 6.6. The results of the present study indicate that stretch-induced hypertrophy can be modulated by varying the amount of stretch applied per day.
  • 7.7. Intermittent stretch can be used to inhibit the regression which occurs when a continuous stretch stimulus is removed.
  • 8.8. Intermittent stretch is a useful model for investigating mechanisms of muscle hypertrophy and inhibition of muscle atrophy.
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17.
  • 1.1. Levels of progesterone and oestrone were estimated by means of RIA in the gonads and pyloric caeca of male specimens of Asterias rubens throughout the reproductive cycle.
  • 2.2. The patterns obtained appeared to be sex-specific on comparison with those of female specimens of A. rubens and it was concluded that progesterone and oestrone in the testes are involved in the regulation of gametogenesis.
  • 3.3. The levels of progesterone in the pyloric caeca were about ten times higher than those in the testes; in the same sequence levels of oestrone were only slightly higher.
  • 4.4. The onset of a new reproductive cycle, taking the abrupt decrease of the pyloric caeca-index as a marker, coincides with a strong decrease of the progesterone level (P < 0.001) and an increase of the oestrone level (P < 0.01) in the pyloric caeca.
  • 5.5. It is supposed that progesterone and oestrone in the pyloric caeca are concerned with making available the materials required for gametogenesis.
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18.
  • 1.1. It is generally assumed that oral blood flow is higher than that of skin, and invasive methods to measure blood flow support this view.
  • 2.2. However, it was not known whether this finding would be confirmed by laser Doppler flowmetry, which is a noninvasive method to measure blood flow.
  • 3.3. The purpose of this study was to compare blood flow in oral and skin regions of the rhesus monkey using laser Doppler flowmetry.
  • 4.4. The results demonstrated that blood flow was significantly higher in oral regions as compared to facial skin (P < 0.05).
  • 5.5. This finding is most likely related to the more abundant capillary supply in oral mucosa as compared to skin.
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19.
  • 1.1. Phospholipase A2 was isolated from Agkistrodon bilineatus venom by Sephadex G-75 and CM-Cellulose column chromatographies.
  • 2.2. The purified phospholipase A2-I gave a single band on disc polyacrylamide gel electrophoresis, isoelectric focusing and sodium dodecyl sulfate polyacrylamide gel electrophoresis.
  • 3.3. The enzyme preparation had a molecular weight of 14,000, isoelectric point of pH 8.77 and possessed 123 amino acid residues.
  • 4.4. The purified phospholipase A2 possessed lethal, indirect hemolytic and anticoagulant activities.
  • 5.5. The enzyme hydrolyzed the phospholipids phosphatidyl choline (PC), phosphatidyl ethanolamine (PE), phosphatidyl inositol (PI) and phosphatidyl serine (PS).
  • 6.6. The concentration of mouse diaphragm was inhibited and the contraction of guinea pig left atrium was increased by phospholipase A2-I.
  • 7.7. Phospholipase A2 activity of this preparation was inhibited by ethylenediamine tetraacetic acid, p-bromo phenacyl bromide, n-bromo succinimide or dithiothreitol, but not by diisopropyl fluorophosphate or benzamidine.
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20.
  • 1.1. The effect of functional overload produced by tenotomy of synergistic gastrocnemius muscle on the expression of myosin heavy chain (MHC) isoforms in the plantaris and soleus muscles of the rat was studied using gradient sodium dodecyl sulfate-acrylamide gel electrophoresis.
  • 2.2. Five weeks tenotomy, the plantaris and soleus muscle weights induced by tenotomy of the gastrocnemius muscle were 44.3% (P < 0.005) and 37.4% (P < 0.005), respectively, heavier than the contralateral control muscles.
  • 3.3. Although four types of MHC isoforms were observed in both control and experimental plantaris, the percentage of MHC isoforms in the control and experimental muscles differed; the hypertrophied plantaris muscle contained more HCI (P < 0.05), HCIIa and HCIId (P < 0.05) and less HCIIb (P < 0.05) than the control muscle.
  • 4.4. The control soleus muscle contained two MHC isofonns, HCI and HCIIa. However, there was only a single HCI isoform in the hypertrophied soleus muscle.
  • 5.5. These results indicate that overloading a skeletal muscle by removing its synergists produces not only the muscle hypertrophy but also the changes in the expression of MHC isofonns.
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