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  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 48 (1987), S. 0 
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract: A 150,000-g supernatant from axoplasm of the giant axon of the stellate nerve of the squid and from rat sciatic and goldfish optic nerves was found to be able to incorporate covalently [3H]putrescine and [3H]spermidine into an exogenous protein (N,N′-dimethylcasein). Incorporation of radioactivity was inhibited by CuSO4, a specific inhibitor of transglutaminases, the enzymes mediating these reactions in other tissues. Analysis of pH and temperature range and enzyme kinetics displayed characteristics predicted for transglutaminase-mediated reactions. Transglutaminase activity increased during regeneration of both vertebrate nerves, but greater activity was found in segments of nerve containing no intact axons than in either intact segments or in segments containing regenerating axons. Polyacrylamide gel electrophoresis of endogenous modified proteins (in the absence of N,N′-dimethylcasein) showed labeling of 18-, 46- and 200-kilodalton proteins by both [3H]putrescine and [3H]spermidine. Analysis of the protein-bound radioactivity from intact and regenerating rat sciatic nerves demonstrated it to be predominantly in the form of the parent radioactive polyamine. These experiments demonstrate the covalent modification of proteins by polyamines at low levels in squid axoplasm and at relatively higher levels in rat sciatic and goldfish optic nerves. In the latter two cases, the activity of these modification reactions may be due in part to the modification of axonal proteins, but the majority of the activity occurs in nonneuronal cells of the nerve.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 46 (1986), S. 0 
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract: Previous experiments have demonstrated that 4S RNA, (tRNA), is transported axonally during the reconnection and maturation of regenerating optic nerves of goldfish. The present experiments were performed to determine if tRNA is transported axonally during elongation of these regenerating nerves and whether, as has been demonstrated in other systems, it participates in posttranslational protein modification (PTPM). [3H]Uridine was injected into both eyes of fish with intact optic nerves and 0, 2, 4, or 8 days after bilateral optic nerve cut. Fish were killed 2 days after injection, and [3H]RNA was isolated from retinae and nerves by phenol extraction and ethanol precipitation. [3H]RNA was fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Although the percentage of [3H]4S RNA remained constant in all retinal and control nerve samples, regenerating nerves showed a twofold increase by 6 days after injury, suggesting that [3H]4S RNA is transported axonally in regenerating nerves as early as 6 days after injury. In other experiments, the 150,000-g supernatant of optic nerves was analyzed for incorporation of 3H-amino acids into proteins. No incorporation of 3H-amino acid was found in the soluble supernatant, but when the supernatant was passed through a Sephacryl S-200 column (removing molecules 〈 20,000 daltons), [3H]Arg, [3H]Lys, and [3H]Leu were incorporated into proteins. This posttranslational addition of amino acids was greater (1.4–5 times for Lys and 2–13 times for Leu) in regenerating optic nerves than nonregenerating nerves, and the growing tips of regenerating nerves incorporated 5–15 times more [3H]Lys and [3H]Leu into proteins than did the shafts. When optic axons were removed from the nerve by degeneration, most of the PTPM activity was lost, indicating a primarily intraaxonal locus for the components of the reaction. SDS-PAGE of 3H-modified proteins showed the presence of radioactivity in proteins of ∼13,000–18,000 38,000–46,000, and 53,000 daltons. These experiments indicate that the components necessary for PTPM by amino acids are transported axonally in regenerating optic nerves of goldfish and that the greatest activity is in the most advanced tips of the growing nerve.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Analytica Chimica Acta 23 (1960), S. 131-135 
    ISSN: 0003-2670
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Analytica Chimica Acta 23 (1960), S. 131-135 
    ISSN: 0003-2670
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Analytica Chimica Acta 23 (1960), S. 131-135 
    ISSN: 0003-2670
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food processing and preservation 13 (1989), S. 0 
    ISSN: 1745-4549
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: “Golden Delicious” and “McIntosh” apples were treated with the sucrose polyester, Semperfresh™, to determine its influence on fruit maturity parameters during cold storage. the objective of this experiment was to determine if Semperfresh application could delay ripening and improve fruit storage stability.Semperfresh treatment reduced apple ripening rate as observed by several parameters including color and texture. Treated apples had delayed color development (internal and external Hunter color reflectance measurements) during 4 months of storage (39°CF; 5°C). Semperfresh increased fruit penetrometer (firmness) readings of both varieties during storage. Measurements for pH, total acidity, and soluble solids were not affected by Semperfresh treatment. Sensory evaluation using a triangle test, indicated that flavor and textural changes were not detected when apples treated with 1.2% Semperfresh were compared to untreated apples after two months storage.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Medical & biological engineering & computing 14 (1976), S. 79-85 
    ISSN: 1741-0444
    Keywords: E.C.G. telemetry ; Sheep ; Electrical stunning ; Carbon-dioxide anaesthesia ; Bleeding out
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Description / Table of Contents: Sommaire On a étudié à l'aide de l'ECG mesuré par télémétrie, les changements d'activité du coeur du mouton saigné après avoir été assommé à l'électricité ou au gaz carbonique. La baisse du taux ventriculaire se produisant alors que le moutons sont saignés après avoir été assommés au courant électrique, est apparemment attribuable à l'anoxie de plus en plus intense plutôt qu'aux changements de pression sanguine. Le taux cardiaque au moment de la saignée dépend directement du taux cardiaque avant l'assommage au courant électrique, mais on n'a découvert aucune relation entre les Watts seconde utilisés et le taux cardiaque à la saignée. Cependant, plus les watts seconde appliqués sont élevés, plus le taux cardiaque minimum enregistré après saignée est bas. L'exposition au gaz carbonique causa une tachycardie au départ, suivie par une baisse du taux cardiaque puis une augmentation secondaire. Le taux augmenta encore lorsque les moutons furent retirés du gaz. Alors que le pourcentage de gaz carbonique utilisé augmentait, la durée de l'activité cardiaque après saignée diminuait. Comme les courants d'assommage élevés causent rapidement des blocages atrio-ventriculaires, ils peuvent avoir des effets adverses sur la saignée si celle-ci dépend de l'activité cardiaque. Les concentrations élevées de gaz carbonique ont pour résultat l'arrêt plus rapide de l'activité cardiaque et risquent d'avoir un effet comparable sur la saignée. Le taux cardiaque plus faible du mouton avant assommage au courant électrique peut indiquer que celui-ci cause par inhérence moins de tension que l'anesthésie au gaz carbonique et risque donc moins d'avoir un effet sur la qualité de la viande.
    Abstract: Zusammenfassung Das durch Telementrie überwachte EKG wurde zur Untersuchung der Änderungen in der Herztätigkeit von Schafen verwendet, die nach elektrischer Betäubung oder Betäubung durch Kohlendioxid ausbluteten. Die Abnahme in der Ventrikelgeschwindigkeit, die auftritt, wenn Schafe elektrischer Betäubung ausbluten, ist offensichtlich auf den zunehmend starken Sauerstoffmangel zurückzuführen und nicht auf Änderungen im Blutdruck. Der Herzschlag beim Fixieren steht im direkten Verhältnis zum Herzschlag vor der elektrischen Betäubung, jedoch wurde zwischen den verwendeten Wattsekunden und dem Herzschlag beim Aderlass kein Zusammenhang festgestellt. Je größer jedoch die Anzahl der angewandten Wattsekunden war, umso niedriger lag der Mindestherzschlag nach dem Fixieren. Bei Gabe von Kohlendioxid wurde eine anfängliche Tachykardie hervorgerufen, gefolgt von abnehmendem Herzschlag und dann einem sekundären Anstieg. Der Herzschlag stieg weiter an, wenn das Schaf vom Gas getrennt wurde. Wenn sich der Prozentsatz des verwendeten Kohlendioxids erhöhte, nahm die Dauer der Herztätigkeit nach dem Aderlass ab. Da hohe Betäubungsstromstärken eine frühe atrioventrikuläre Blockierung verursachen, könnten sie das Ausbluten nachteilig beeinflussen, wenn dies von der Herztätigkeit abhängt. Durch hohe Kohlendioxidkonzentrationen ergibt sich eine frühere Einstellung der Herztätigkeit, durch die das Ausbluten in ähnlicher Weise beeinträchtigt werden könnte. Die niedrigere Herzfrequenz von Schafen vor der elektrischen Betäubung kann darauf hinweisen, daß die elektrische Betäubung die Schafe nicht so sehr beansprucht wie eine Kohlendioxid-Betäubung und sich daher wahrscheinlich weniger auf die Fleischqualität auswirkt.
    Notes: Abstract The e.c.g., monitored by telemetry, was used to study changes in the heart activity of sheep bled out after electrical stunning or carbon-dioxide anaesthesia. The decrease in ventricular rate which occurs as sheep are bled out after electrical stunning is apparently attributable to increasingly severe anoxia, rather than to changes in blood pressure. The heart rate at sticking is directly related to the heart rate before electrical stunning, but no relationship was found between the wattseconds used and the heart rate at sticking. However, the greater the number of wattseconds applied, the lower the minimum heart rate recorded after sticking. Exposure to carbon dioxide caused an initial tachycardia, followed by a decreased heart rate and then a secondary increase. The rate rose further when the sheep were removed from the gas. As the percentage of carbon dioxide used increased, the duration of heart activity after sticking decreased. Since high stunning currents cause early atrioventricular block, they might adversely affect bleeding out, if this is dependent on heart activity. High concentrations of carbon dioxide results in earlier termination of heart activity and might affect bleeding out similarly. The lower heart rate of sheep before electrical stunning may indicate that it is inherently less stressful than carbon-dioxide anaesthesia and so less likely to affect meat quality.
    Type of Medium: Electronic Resource
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