Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 2020-2024
  • 2020-2023
  • 1995-1999
  • 1990-1994  (4)
  • 1960-1964  (2)
  • 1950-1954
  • 1930-1934
  • 1920-1924
  • 1880-1889
  • 1830-1839
  • 2022
  • 2020
  • 1992  (4)
  • 1964  (2)
  • 1961
  • 1952
  • 1888
  • 1885
  • Free radicals
Source
Material
Years
  • 2020-2024
  • 2020-2023
  • 1995-1999
  • 1990-1994  (4)
  • 1960-1964  (2)
    • +
Year
Keywords
  • 1
    Electronic Resource
    Electronic Resource
    Amino acids and their derivatives as radioprotective agents (1992)
    Springer
    Amino acids 3 (1992), S. 25-52 
    Details
    ISSN: 1438-2199
    Keywords: Amino acids ; Radiation toxicity ; Radioprotection ; Thiols ; Free radicals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Numerous amino acids and their analogs are capable of protecting biological systems from the toxic effects of ionizing radiation. These radioprotective agents can be classified into two broad groups, depending upon the presence or absence of a free or potentially free sulfhydryl group. The sulfhydryl-containing compounds have been studied extensively and are thought to exert their radioprotective effects by several mechanisms, including free radical scavenging and hydrogen atom donation. Several non-sulfhydryl-containing amino acids are also being investigated for their radioprotective effects. These agents are less well known than the familiar sulfhydryl compounds, but possess very interesting protective qualities. In short, the study of amino acids and their derivatives as radioprotective agents continues to contribute to an understanding of processes involved in radiation toxicity and to offer new compounds with potential application to situations of human exposure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00806007
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Pulse radiolysis of aromatic amino acids — State of the art (1992)
    Springer
    Amino acids 2 (1992), S. 195-214 
    Details
    ISSN: 1438-2199
    Keywords: Amino acids ; Pulse radiolysis ; Aromatic amino acids ; Reaction mechanisms ; Free radicals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The pulse radiolysis method as well as the primary processes of water radiolysis and the spectroscopic characteristics of H, OH, HO2/O2 − and e aq - are briefly presented. Subsequently, kinetic and spectroscopic data of the transients resulting from the resolved multi site attack on aromatic amino acids are discussed. The reactivity of H and e aq - with the same substrates, as well as the effect of oxygen on the major radiolytic processes are reviewed. Finally, the formation of tryptophan radical cation is mentioned shortly. The presented radiation mechanisms are the fundamentals for radiolytic processes occurring in proteins, enzymes and hormones in the living cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00805942
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Selegiline — An overview of its role in the treatment of Parkinson's disease (1992)
    Springer
    Journal of molecular medicine 70 (1992), S. 459-462 
    Details
    ISSN: 1432-1440
    Keywords: Selegiline ; Parkinson's disease ; MAO-B ; Free radicals ; Dopamine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Selegiline (10 mg per day) selectively inhibits monoamine oxidase type B and thus thwarts the metabolism of dopamine by this enzyme. Selegiline has been used in the therapy of Parkinson's disease since 1986. It enhances the efficacy of levodopa, allows a reduction of the levodopa dose, and improves fluctuations in disability. It also interacts with mechanisms suspected of playing a role in the progression of the disease. Animal studies have shown that selegiline prevents the development of a Parkinson-like syndrome induced by the neurotoxin MPTP. It decreases oxidative stress resulting from the metabolism of dopamine via MAO-B. Clinical studies have shown that selegiline is effective in the therapy of untreated de novo patients the progression of symptoms demanding the introduction of levodopa into the therapy was delayed, and the risk of needing levodopa treatment within one year was reduced by 57% with selegiline. The mode of action of this drug in the treatment of early Parkinson's disease is still under discussion. There is strong evidence that selegiline may slow the progression of the disease, but a direct symptomatic effect cannot be excluded.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00235534
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Repetitive static muscle contractions in humans —a trigger of metabolic and oxidative stress? (1992)
    Springer
    European journal of applied physiology 64 (1992), S. 228-236 
    Details
    ISSN: 1439-6327
    Keywords: Adenine nucleotides ; Exertion ; Free radicals ; Human ; Lactate ; Muscle metabolism ; Phosphocreatine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Repetitive static exercise (RSE) is a repetitive condition of partial ischaemia/reperfusion and may therefore be connected to the formation of oxygen-derived free radicals and tissue damage. Seven subjects performed two-legged intermittent knee extension exercise repeating at 10 s on and 10 s off at a target force corresponding to about 30% of the maximal voluntary contraction force. The RSE was continued for 80 min (n=4) or to fatigue (n=3). Four of the subjects also performed submaximal dynamic exercise (DE) at. an intensity of about 60% maximal oxygen uptake (VO2max) for the same period. Whole body oxygen uptake (VO2) increased gradually with time during RSE (P〈0.05), indicating a decreased mechanical efficiency. This was further supported by a slow increase in leg blood flow (P〈0.05) and leg oxygen utilization (n.s.) during RSE. In contrast, prolonged RSE had no effect onVO2 during submaximal cycling. Maximal force (measured in six additional subjects) declined gradually during RSE and was not completely restored after 60 min of recovery. After 20 and 80 min (or at fatigue) RSE phosphocreatine (PC) dropped to 74% and 60% of the initial value, respectively. A similar decrease in PC occurred during DE. Muscle and arterial lactate concentrations remained low during both RSE and DE. The three subjects who were unable to continue RSE for 80 min showed no signs of a more severe energy imbalance than the other subjects. A continuous release of K+ occurred during both RSE and DE. The total muscle loss of K+ was about 3% and 6% of the total muscle K+ content during RSE and DE, respectively. Muscle glutathione, glutathione disulphide, ubiquinone and α-tocopherol are involved in the cellular defence system against free radicals. During RSE and DE these parameters were unchanged and plasma malondialdehyde (a product of free radical induced lipid peroxidation) remained below the detection limit. In conclusion, prolonged RSE resulted in a gradual decrease in PC, mechanical efficiency and maximal force. There were no signs of an enhanced rate of free radical formation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00626285
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Intramolecular Free-Radical Reactions (1964)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 3 (1964), S. 525-538 
    Details
    ISSN: 0570-0833
    Keywords: Radical reactions ; Free radicals ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In the present article an attempt is made to summarize the steric requirements and the influence of neighboring groups which determine the course of intramolecular radical reactions. Steroids are used as substrates for these reactions, since here the spatial arrangement of the ring members and the distances between substituents are largely fixed. Furthermore, intramolecular free-radical reactions are of practical importance in steroid chemistry in connection with substitution at non-activated carbon atoms. Almost all the reactions discussed begin with the formation of an oxygen radical by oxidation of an alcohol with lead tetraacetate or by homolysis of the corresponding hypoiodite.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196405251
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Free Radicals and Free-Radical Reactions of Monovalent and Divalent SulfurFree-radical reactions of tetra- and hexavalent sulfur are not considered in this work. For a survey of these reactions, see [16], p. 326. (1964)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 3 (1964), S. 602-608 
    Details
    ISSN: 0570-0833
    Keywords: Free radicals ; Radical reactions ; Sulfur ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Organic free radicals of monovalent sulfur have not been hitherto observed in solution or in melts. Steric hindrance and resonance stabilization, which are responsible for the stability of the triarylmethyl, diphenylnitrogen, and phenoxyl radicals, are apparently insufficient to stabilize the organic free radicals of monovalent sulfur in such concentrations that they can be detected by current physical methods. - It was only in 1963 that aminopolysulfur radicals (R2N—Sn—S·) were detected in solution, and arylsulfur radicals (Ar-S·) and phenylselenium radicals were isolated at ca. -180°C. - Organically bound sulfur can be stabilized in the free-radical state if association of the radicals is prevented by fixing in a crystal lattice (“cystine radical”), by repulsion between radical ions (sulfinium salts), or by freezing-in (arylsulfur radicals).
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196406021
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...