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
  • 1980-1984  (313)
  • Engineering  (191)
  • Rat  (122)
  • Magnetic resonance imaging
  • 1
    Electronic Resource
    Electronic Resource
    Effects of acute administration of cyclazocine on the metabolism of biogenic amines in different regions of rat brain (1981)
    Springer
    Psychopharmacology 75 (1981), S. 79-83 
    Details
    ISSN: 1432-2072
    Keywords: Cyclazocine ; Acute treatment ; Dopamine ; Noradrenaline ; Serotonin ; Monoamine metabolites ; Brain regional assay ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The effects of cyclazocine on the metabolism of dopamine (DA), noradrenaline (NA) and 5-hydroxytryptamine (5-HT) in regions of rat brain were studied by measuring changes in the levels of the monoamines and their major metabolites. Doses ranging from 4–32 mg/kg were tested. Rats were sacrificed 1 or 2 h after administration of the drug, according to the experiment. Administration of cyclazocine significantly decreased DA concentration and increased the levels of DOPAC and HVA in striatum. Cyclazocine decreased the levels of NA, and markedly increased the levels of MHPG-SO4 and 5-HIAA in cortex, hypothalamus, midbrain and pons-medulla, while little change in 5-HT concentration, except a decrease after the highest dose, was observed. These changes in the metabolism of the monoamines differed in their amplitude and temporal nature. The possible roles of dopaminergic, noradrenergic and serotoninergic neurons in different brain regions are discussed in relation to modifications of locomotor activity and the induction of bizarre behavior resulting from cyclazocine administration in rats. These investigations may add to the understanding of the mechanism of psychotomimetic effects produced in man by this drug.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00433507
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Guanfacine and clonidine: antihypertensive and withdrawal characteristics after continuous infusion and its interruption in the spontaneously hypertensive and normotensive rat (1982)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 319 (1982), S. 82-86 
    Details
    ISSN: 1432-1912
    Keywords: Guanfacine ; Clonidine ; Continuous infusion ; Withdrawal ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In conscious unrestrained spontaneously hypertensive and normotensive rats, prepared with permanently indwelling abdominal aortic catheters, the effects on blood pressure and heart rate of a 12-day continuous subcutaneous infusion of guanfacine (10 mg/kg/day) and clonidine (500 μg/kg/day) and sudden interruption of these treatments were studied. Both drugs significantly and consistently reduced the mean arterial pressure and heart rate throughout the infusion period in the SH rats, but not in the normotensive animals. The magnitude of the effects of both drugs in the SH rat were similar. Following withdrawal of treatment with guanfacine, a discontinuation syndrome was evoked, much less severe than that observed after suspension of the infusion with clonidine. The withdrawal syndromes were characterized by an overshoot of heart rate and a period of blood pressure lability. In spite of the ineffectiveness of guanfacine and clonidine to reduce blood pressure and heart rate consistently in the normotensive rat, similar withdrawal patterns as those found in the SH rat were observed. These findings are in general agreement with the results previously found in clinical studies in hypertensive patients. The spontaneously hypertensive rat may prove a suitable animal model for pre-clinical studies of discontinuation symptoms after cessation of treatment with antihypertensive drugs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00491483
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    The perineuronal net in the fastigial nucleus of the rat cerebellum (1984)
    Springer
    Anatomy and embryology 170 (1984), S. 79-85 
    Details
    ISSN: 1432-0568
    Keywords: Perineuronal net ; Astrocytes ; Fastigial nucleus ; Cerebellum ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The morphological study of the rat fastigial nucleus with the Golgi-Rio Hortega method showed the presence of glial perineuronal nets surrounding the large neurons, but not the small ones. This perineuronal net appeared as a mesh of tenuous glial processes which covers the neuronal perikarya and proximal dendrites. The small alveolate compartments in this mesh seem to correspond to the holes for the synaptic boutons. Our results also indicate that the perineuronal net is derived from interneuronal protoplasmic and velate astrocytes. Using camera lucida drawings of this perineuronal net we have made a quantitative estimation of the size and density of synaptic boutons on these large neurons. The average numerical density of synaptic boutons was about 19 per 100 μm2 of the neuronal surface, the mean area of the synaptic holes being 2.5 μm2. Furthermore, the quantitative data evidence that about 52.5% of the neuronal surface is presumably occupied by synaptic boutons whereas the remaining 47.5% is covered by the glial processes of the perineuronal net. Semithin sections prepared from thick Golgi sections were used for the cytological study of the neurons surrounded by this glial pericellular network. The possible functional significance of the perineuronal net in the regulation of synaptic transmission in the fastigial cerebellar nucleus is briefly discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00319461
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Increase of δ-Aminolevulinic Acid Dehydratase (ALAD) in rat erythrocytes in lead poisoning (1983)
    Springer
    Archives of toxicology 52 (1983), S. 1-11 
    Details
    ISSN: 1432-0738
    Keywords: Lead poisoning ; Erythrocytes ; δ-Aminolevulinic acid dehydratase(ALAD) ; Rat ; Porphyrins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The well known fact that the activity of δ-aminolevulinic acid dehydratase (ALAD: EC 4.2.1.24) is reduced in red cells of animals with lead poisoning was found to be upset, by using a modified method of Gibson's original procedure, for determination of activated ALAD activity. The modified method involves addition of 0.2 mM Zn2+ and then preheating the enzyme solution at 60° C for 5 min before following Gibson's original procedure. With this methodological modification, the ALAD activity of erythrocytes of rats poisoned with lead was found increased. Furthermore, the enzyme was purified from the peripheral blood of lead-poisoned rats. ALAD protein in peripheral blood was also determined by single radial immuno diffusion using rabbit anti-serum raised against rat liver ALAD. As the result, the ALAD activity obtained from the modified method was found to be directly proportional to the absolute amount of enzyme proteins determined both by chemically and immunochemically. The modified method for measuring true ALAD content in blood cells in lead poisoning is more reliable than previous ones.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00317977
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Cerebellar intranuclear inclusions in chronically alcoholized rats (1981)
    Springer
    Cell & tissue research 216 (1981), S. 227-230 
    Details
    ISSN: 1432-0878
    Keywords: Cerebellum ; Nuclear inclusions ; Alcohol ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Nuclear rods and sheets are described in neurons from the cerebellar cortex of rats alcoholized through ingestion of a 20 % aqueous ethanol solution over a period of 90 and 180 days. An eventual relationship between these nuclear inclusions and alcoholization is advanced.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234558
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    A modified plasticity theory for porous metals (1980)
    Chichester [u.a.] : Wiley-Blackwell
    International Journal for Numerical Methods in Engineering 15 (1980), S. 649-660 
    Details
    ISSN: 0029-5981
    Keywords: Engineering ; Engineering General
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mathematics , Technology
    Notes: A plasticity theory for porous metals is proposed. A simple model of a porous materials is analysed by the finite element method. Small strain elastic-plastic analysis provides stress-strain curves, yield stressed and incremental plastic strain vectors for different void ratios. An assessment is made of an existing yield criterion for porous metals. A modified yield criterion and plastic potential function and, consequently, different plasticity equations are given. Reasonable agreement is obtained between the present numerical results and previous results in the literature.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/nme.1620150503
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Fundamlntals of soil dynamics, B. M. Das, Elsevier Science Publishing Co., New York, 1983. No. of pages: 399. Price: $32.50 (1984)
    Chichester [u.a.] : Wiley-Blackwell
    International Journal for Numerical Methods in Engineering 20 (1984), S. 1952-1952 
    Details
    ISSN: 0029-5981
    Keywords: Engineering ; Engineering General
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mathematics , Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/nme.1620201016
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    A statistical study of fabric in a random assembly of spherical granules (1982)
    New York, NY [u.a.] : Wiley-Blackwell
    International Journal for Numerical and Analytical Methods in Geomechanics 6 (1982), S. 77-94 
    Details
    ISSN: 0363-9061
    Keywords: Engineering ; Engineering General
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Notes: It is commonly accepted that the mechanical behaviour of granular masses is strongly affected by their microstructure, namely the relative arrangement of voids and particles, i.e. the granular fabric. Therefore, parameters which characterize the granular fabric are of paramount importance in a fundamental description of the overall macroscopic stresses and deformation measures. In this paper several measures of granular fabric are introduced for a random assembly of spherical granules, using a statistical approach. In particular, a second-order symmetric tensor, Fij, emerges from this consideration, which seems to be of fundamental importance for the description of fabric, and which is closely related to the distribution of the contact normals in the assembly. The relation between fabric measures presented here and those discussed by other investigators is also discussed.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/nag.1610060106
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    On statistical description of stress and fabric in granular materials (1982)
    New York, NY [u.a.] : Wiley-Blackwell
    International Journal for Numerical and Analytical Methods in Geomechanics 6 (1982), S. 95-108 
    Details
    ISSN: 0363-9061
    Keywords: Engineering ; Engineering General
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Notes: The notion of overall macroscopic stress in granular masses is examined from a fundamental point of view by a statistical consideration of the contact forces that are transmitted by the contacting granules at the microscale. This examination leads in a natural way to relations between the macroscopic stress and the resulting granular fabric. The overall stresses are expressed in terms of the contact forces in two different but complementary ways: (1) by a statistical averaging over the sample volume of contact forces and “branches” which are vectors connecting the centroids of two contacting granules; and (2) by defining the overall tractions transmitted across an interior imagined plane as the sum of the contact forces which represent the mechanical effect of granules on one side of a unit area of this plane, upon those on the other side. Conditions under which the two representations of overall stresses are equivalent, are examined in detail. In addition, explicit results are given, which, define stresses in terms of the fabric and other microstructural characteristics of the granular mass.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/nag.1610060107
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Numerical calculation of transitional boundary layers (1982)
    Chichester : Wiley-Blackwell
    International Journal for Numerical Methods in Fluids 2 (1982), S. 1-23 
    Details
    ISSN: 0271-2091
    Keywords: Transition ; Boundary Layers ; Models of Turbulence ; Engineering ; Engineering General
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: A computational procedure for compressible axisymmetric boundary layers, on bodies of revolution, in transition from laminar to turbulent flow, is introduced. The procedure is an extension of a former method, due to Patankar and Spalding.The flow field is computed by solution of four simultaneous equations for the momentum, the thermal energy, the turbulence energy amplitude and the turbulent scale.The results show good agreement with existing theoretical and experimental data.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/fld.1650020102
    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...