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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 26 (1976), S. 1-17 
    ISSN: 1432-1106
    Keywords: Medial geniculate body ; Neuronal geometry ; Synaptic triplets ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Golgi and electron microscopic analysis of the known cellular layers in concentric shells of the ventro-lateral portion of the medial geniculate body revealed a flat grid of high density neuropil filling the space between the geniculocortical relay cells, forming essentially a single cell layer in each lamina. The “skeleton” of this neuropil grid is made up by the interdigitating dendritic tufts of the geniculocortical relay cells, joined together by a rich system of desmosomoid adhesion plaques. The “holes” of the “skeleton” are filled in by the multilobed dendritic appendages of Golgi type II interneurons and the grape-like terminals of the inferior collicular specific afferents. Additional axon terminals of other sources — terminals of descending corticogenicular fibers, axons of the Golgi type II interneurons and terminals of the initial collaterals of the geniculocortical relay cells — contribute only to a very insignificant fraction of neuropil volume. The Golgi type II interneurons are oriented in perpendicular direction to the cell layers so that they may bridge with their dendrites several successive layers. Although the general expression “synaptic glomeruli” used in other relay nuclei for this type of specific synaptic arrangement is hardly applicable to this grid-like neuropil, the essential synaptic articulation pattern of all thalamic relay nuclei is well maintained. The specific inferior collicular afferents are presynaptic to both relay cell dendrites and to the multilobed dendritic appendages of Golgi type II cells, which in turn are presynaptic to the same dendritic regions of the relay cells receiving the bulk of the specific afferents.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 26 (1976), S. 19-37 
    ISSN: 1432-1106
    Keywords: Medial geniculate body ; Interneurons ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Three different types of interneurons can be separated in the Golgi picture, and many of their details can be identified under the electron microscope, in the medial geniculate body (MGB) of the cat: (1) typical short axon Golgi II. cells of the thalamic type, (2) somewhat larger Golgi type II cells with medium range axon, and (3) spidery neurogliform short axon cells. The most distinctive features of the two first types (1) and (2) are their irregular drumstick shape appendages, increasing in number as well as in length and irregularity of their stalks towards the periphery of the dendrites. These appendages form the vast majority of synaptic profiles in the aggregations of synaptic neuropil (glomeruli) of the nuclei, and they are both presynaptic and postsynaptic by the usual standards applied for the evaluation of the polarity of synapses. The characteristic beaded dendrites of the (3) neurogliform cell type can be recognised particularly easily in the electron microscope picture. They are both presynaptic and postsynaptic in structural polarity. All identified process profiles of interneurons contain flattened (F.-type) or pleomorphic synaptic vesicles. Membrane contacts, in which the interneurons appear to be presynaptic are either of the symmetric (Gray type II) or of an intermediate type. The membrane contacts of postsynaptic portions of the interneurons are usually of the asymmetric type (Gray type I) and the presynaptic profiles contain round (R-type) vesicles. The larger one have been shown already earlier to be derived from specific sensory (inferior collicular) afferents, while many of the smaller ones could be identified in the present study as being derived from cortico-geniculate descending pathways, arising from the auditory areas. Some of the synaptic contacts of the interneurons are apparently derived from other interneurons, the presynaptic profiles being often equivocal or more likely of axonal origin (all interneurons have clear axons in the Golgi picture). The occurrence of three distinct types of interneurons — probably all of inhibitory nature — the complexity in synaptic arrangement, and more particularly in the dendritic linkage of numerous synaptic sites does not favour such simple explanations as surround inhibition by forward or by backward inhibition, but suggests more sophisticated modes of impulse processing in the MGB.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1436-5073
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary In the turbidimetric determination of traces of phosphoric acid, in accord with the Hegedüs and Dvorszky version, employing strychnine nitrate, excellent reproducibility is attained only when the MoO3 employed for the preparation of the reagent contains 0.2–0.5% WO3/MoO3. If less than 0.01% WO3/MoO3 is present, large deviations in the obtained values ensue.
    Notes: Zusammenfassung Mit der turbidimetrischen Strychninnitrat-Methode für Phosphorspurenbestimmung nach der Version von Hegedüs und Dvorszky kann man nur dann ausgezeichnete Reproduzierbarkeit erreichen, wenn das für die Reagenszubereitung verwendete MoO3 0,2–0,5% WO3/MoO3 enthält. Falls weniger als 0,01% WO3/ MoO3 anwesend sind, kommt es zu starken Meßwertschwankungen.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Journal of thermal analysis and calorimetry 11 (1977), S. 249-256 
    ISSN: 1572-8943
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Résumé On a étudié dans quelques espèces typiques de boues rouges de Hongrie l'effet des variations de pression sur la forme des courbes TG, TGD et ATD ainsi que les spectres de masse des phases hydroxyde et carbonate. La variation de la pression entraîne des vitesses de décomposition différentes. Il en résulte une meilleure séparation des phénomènes dans le cas où ceux-ci se chevauchent ainsi que des avantages du point de vue de l'analyse des phases. L'analyse des phases présentes dans les boues rouges a été effectuée par extraction à l'eau. Les extraits et les résidus solides ont été identifiés par spectrométrie infrarouge et par diffraction des rayons X.
    Abstract: Zusammenfassung Die Wirkung der Druckänderung auf die Form der TG-, DTG- und DTA-Kurven, sowie der MS-Spektra der Hydroxid- und Carbonatphasen in einigen typischen ungarischen Rotschlamm-Sorten wurde geprüft. Die Druckänderung verursachte verschiedene Zersetzungsgeschwindigkeiten der Phasen, führte zur besseren Auftrennung der sich überlappenden thermischen Kurven, und war ausserdem auch hinsichtlich der Phasenanalyse vom Vorteil. Zur Phasenanalyse wurden die Rotschlämme mit Wasser extrahiert und die Extrakte und festen Rückstände mittels IR- und Röntgenmethoden identifiziert.
    Notes: Abstract The effect of reduction of pressure on the shapes of the TG, DTG and DTA curves and the mass-spectra of hydroxide and carbonate phases was investigated in some typical Hungarian red muds. The pressure change caused different decomposition rates of the phases and resulted in better separation of the overlapping thermal curves; this led to advantages as regards phase analysis. For phase analysis the red muds were extracted with water, and the extracts and solid residues were identified by IR- and X-ray methods.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Journal of materials science 13 (1978), S. 2541-2547 
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Connected with the examination of the thermal polycondensation of ammonium paratungstate pentahydrate the chemical and morphological properties of intermediate phases formed during the thermal decomposition of APT have been investigated. We have studied the pH and the turbidity of the aqueous solutions of the intermediate phases, the solubility of the phases, and their rehydratation capability as well as the morphology of the crystallite granules and the grain size distribution. These properties of the original APT have been related to the same properties of the products of decomposition formed between different temperature ranges. The results obtained show unambiguously that each of the above mentioned properties suddenly changes in the temperature range 225 to 250°C. This temperature range coincides with the formation temperature of a new phase called APT II. The most probable formula of APT II is (NH4)8 [H2W13O43(OH)2]·H2O.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Journal of materials science 13 (1978), S. 2541-2547 
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Connected with the examination of the thermal polycondensation of ammonium paratungstate pentahydrate the chemical and morphological properties of intermediate phases formed during the thermal decomposition of APT have been investigated. We have studied the pH and the turbidity of the aqueous solutions of the intermediate phases, the solubility of the phases, and their rehydratation capability as well as the morphology of the crystallite granules and the grain size distribution. These properties of the original APT have been related to the same properties of the products of decomposition formed between different temperature ranges. The results obtained show unambiguously that each of the above mentioned properties suddenly changes in the temperature range 225 to 250°C. This temperature range coincides with the formation temperature of a new phase called APT II. The most probable formula of APT II is (NH4)8 [H2W13O43(OH)2]·H2O.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 9 (1975), S. 261-271 
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The π-electronic structure and spectra of the protonated aromatic carboxylic acids, aldehydes and ketones have been calculated by the Pariser-Parr-Pople method. An essential modification was that the positive charge has been considered as delocalized within the substituent group. The best agreement for the cation of benzoic acid was obtained using a symmetric carboxy model with equal charges on both oxygen atoms. This model gave equally good results for the protonated fluoro-, chloro- and methylbenzoic acids, as well. The delocalized charge model was successfully applied in the calculation of aromatic aldehydes and ketones. The methyl group was treated both as a one- and as a two-centre substituent.
    Additional Material: 7 Tab.
    Type of Medium: Electronic Resource
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