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  • 1
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract— The effect of stimulating the electric organ of Torpedo marmorata, anaesthetized with 0.01% Tricaine methane sulphonate, by means of electrical stimulation (5/s) administered via an electrode placed on the electric lobe has been studied electrophysiologically, biochemically and morphologically. The response of the organ declined to about 50 per cent of its initial value after about 500 stimuli, by a further 10 per cent after another 500 stimuli and then to about 12 per cent of the initial value after a further 1000 stimuli. Thereafter the response fell off progressively. However, even when the response was less than 1 per cent of its initial value, the organ had considerable powers of recuperation during a 30-s rest period, to 30–50 per cent of its initial value.The fall in response was accompanied by a reduction in vesicle size and number, an increase in the area of the presynaptic membrane and a fall in the protein, total nucleotide, ATP and acetylcholine content of the vesicle fraction isolated from the stimulated tissue. However, whereas vesicle numbers and the protein and total nucleotide content of the vesicle fraction fell by only about 50 per cent, vesicular ATP and acetylcholine levels were reduced to about 10 per cent. An analysis of the covariance of vesicular ATP and acetylcholine showed an initial loss of an acetylcholine-rich (relative to ATP) population of vesicles. The early loss of vesicular protein and nucleotide and vesicle numbers as well as the morphological changes seen would be consistent with a loss of vesicles due to fusion with the external membrane. The preferential loss of acetylcholine and ATP from the vesicle fraction indicates that the vesicles surviving the stimulation procedure have been utilized in a number of cycles causing the progressive fall in vesicle volume, and acetylcholine and ATP content.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: —During stimulation there occurred a decay in electrical response, vesicular acetylcholine, ATP and nucleotide as well as a loss of vesicle number and a decrease in vesicle diameter in the electric organ of Torpedo. These alterations were re-established during a subsequent recovery period. The different parameters recovered at different rates. Firstly, electrical response to single pulses recovered to prestimulation values within about 5 h. Vesicle number and diameter as well as bouton size were found to be re-established fully after 24 h. The newly formed vesicles appeared to be empty as vesicular acetylcholine, ATP and total nucleotide recovered much more slowly and were back to control values after about three days. Acetylcholine reappeared more quickly in the vesicles than ATP. Only after recovery of the vesicular pool of transmitter and ATP did the electric organ regain full stability of the electric discharge pattern on restimulation.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 357 (1972), S. 53-66 
    ISSN: 1432-2307
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In den am weitesten ausgereiften juxtamedullären Nephronen der frühfetalen Nachniere des Menschen liegen myofilamentäre intraepitheliale Strukturen vor. Sie treten in der parietalen Bowmanschen Kapsel und im proximalen Tubulus am auffälligsten in Erscheinung. Da eine sichere Identifizierung der Filamente als Myofilamente in konventionell-chemisch fixierten Präparaten nicht möglich ist, wurden unter Ausnutzung des Prinzips der Fraunhoferschen Beugung an einem Laser-Meßplatz gewonnene Beugungsspektren von intracytoplasmatischen Filamenten im proximalen Tubulus, im parietalen Bowmanschen Kapselepithel und im visceralen Glomerulusepithel und von Myofilamenten glatter Gefäßwandmuskelzellen vergleichend analysiert. Dabei ergab sich für alle Objekte ein gemeinsamer Strukturparameter in dem engen Bereich von 81 ± 8 Å. Dieser Befund wird als ein Argument für die Myofilamentnatur der beobachteten intraepithelialen Strukturen angesehen. Die Einzelbeobachtung eines Nerv-Epithel-Kontaktes an der parietalen Bowmanschen Kapsel läßt zusammen mit eigenen früheren Befunden eine funktionelle Beeinflussung 'des „contractilen Apparats“ der Niere durch das vegetative Nervensystem möglich erscheinen.
    Notes: Summary Myofilamentary intraepithelial structures are found in the most mature juxtamedullary nephrons of the early fetal metanephros of man. These structures are most distinctive in the parietal part of Bowman's capsule and in the proximal tubulus. Definite identification as myofilaments is impossible in preparations which have been fixed with conventional chemical methods. Making use of Fraunhofer's diffraction principle, diffraction spectra of intracytoplasmatic filaments of the proximal tubulus, of epithelia of the parietal part of Bowman's capsule, of visceral glomerular epithelia and of smooth muscle cell filaments were obtained with a laser measuring system and comparatively analyzed. Analysis of all objects revealed a common structural parameter within the narrow range of 81 ± 8 Å. This observation is a substantial argument for the myofilamentary nature of the intraepithelial structures. Together with previous personal findings the single observation of nerve-epithelium contact in the parietal part of Bowman's capsule suggests a functional influence of the autonomous nervous system on the “contractile apparatus” of the kidney.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Archives of orthopaedic and trauma surgery 69 (1970), S. 60-67 
    ISSN: 1434-3916
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé 25 cas de luxations acromio-claviculaires ont été traitées par des techniques différentes. Or, la méthode opératoire la plus appropriée nous paraît dans une suture ou substitution des ligaments acromio-claviculaires renforcées par une fixation métallique pour la durée de guérison.
    Abstract: Zusammenfassung Unser Krankengut von 25 Acromio-Clavicular-Luxationen (AC-Luxationen), das nach verschiedenen Techniken behandelt wurde, zeigte nur dann ein gutes Ergebnis, wenn die Operationsmethode folgendes beinhaltete: Naht oder Substitution sowohl der acromio-claviculären als auch der coraco-claviculären Bänder, mechanische Fixation auf Höhe des AC-Gelenkes und der CC-Bänder für die Dauer der Heilung. Diese Methode berücksichtigt speziell die Scher- und Zugkräfte, denen das AC-Gelenk ausgesetzt ist.
    Notes: Summary 25 complete acromio-clavicular dislocations were treated by several methods. The best results were obtained following direct suture or substitution of both acromio-clavicular and coraco-clavicular ligaments and solid mechanical fixation at the AC-joint and at the coraco-clavicular ligaments.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Chemie 103 (1972), S. 418-425 
    ISSN: 1434-4475
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es werden die Dimethoxyäthan-(DME-)Addukte von TiCl4, VCl4, CrCl3 und MnCl2 dargestellt. Neben einigen schon beschriebenen Addukten wurden VCl4 · 2DME, CrCl3 ·DME und MnCl2 ·DME neu isoliert. Auf Grund unserer Untersuchungen liegencis-oktaedrische Strukturen vor, die beim Chrom zu einer dimeren, beim Mangan zu einer polyoktaedrischen Anordnung verknüpft sind.
    Notes: Abstract We have prepared some dimethoxyethane-adducts of TiCl4, VCl4, CrCl3, and MnCl2. In addition to some known products, we have isolated the new compounds VCl4 · 2DME, CrCl3 ·DME, and MnCl2 ·DME. On the basis of our investigations, the compounds havecis-octahedral structures, the chromium compound possessing a dimeric, the manganese compound a polyoctahedral arrangement.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 0942-0940
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 29 (1974), S. 157-174 
    ISSN: 1432-0533
    Keywords: Brain Edema ; Necrosis ; Cytometry (Neurons, Neuroglia, Capillaries) ; Blood Coagulation ; Rabbit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Combined cytometric studies and control of blood coagulation of a cold injury brain edema in the left parietal cortex (cortical layers I and II) of rabbits had the following results: a) Within the first 30 min after the lesion, a hypocoagulability was observed only in the cerebral vessels and significant correlations are limited to the changes between the nuclear size of endothelial, glial and nerve cells of the left, lesioned, cortical area. An increase, however, in the diameter of the cytoplasmic profiles of the endothelial cells and of the pericapillary glial end feet of the right cortical layer II can be interpreted as an early reaction of these cell types to the disturbed function of the lesioned cortical area. b) 60 min after the lesion there is a general hypercoagulability which is followed by a general hypocoagulability 12 hrs later. Endothelial, glial and nerve cells of the right hemisphere are more and more influenced by the increasing edema of the left hemisphere (for correlations see p. 16). It is suggested that the changes of permeability in the lesioned hemisphere locally affect blood coagulation and thus have an influence via the cerebral vessels on the function of nerve cell-glia complexes in the contralateral hemisphere.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    European archives of psychiatry and clinical neuroscience 216 (1972), S. 82-100 
    ISSN: 1433-8491
    Keywords: Sleep-EEG ; Parkinson's Disease ; l-DOPA ; Sleep Stages ; Sequential Analysis ; Schlaf-EEG ; Parkinson-Syndrom ; l-DOPA ; Schlafstadien ; Sequenzanalysen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 1. Der Einfluß der l-DOPA-Therapie auf den Nachtschlaf wird bei 24 Parkinson-Patienten (47–72 Jahre alt) untersucht. Neben polygraphischer Ableitetechnik wird das Tönnies-EISA-Verfahren angewendet. 2. Vor der Behandlung zeigen 40 polygraphische Nachtableitungen, daß Parkinson-Kranke häufig Schlafstörungen haben mit vermehrten und verlängerten Wachphasen, vermindertem REM- und Tiefschlafanteil und gestörtem cyclischem Ablauf der Schlafstadien, verglichen mit gleichaltrigen Gesunden. 3. Unter l-DOPA-Therapie ergeben 40 weitere Schlaf-EEG Veränderungen des Nachtschlafs. Dabei werden zwei verschiedene Gruppen mit klarer Beziehung zum motorischen Therapieerfolg unterschieden. Gruppe I mit guter Besserung von Akinese und Rigor zeigt auch eine deutliche Tendenz zur Normalisierung des Nachtschlafs: Verminderung der Wachphasen, Zunahme von REM-Schlaf und synchronisiertem Schlaf und geringer gestörte Stadien-Sequenz. Bei Gruppe II mit geringem oder fehlendem motorischen Therapieerfolg wird zwar der gestörte Nachtschlaf nicht gebessert, aber der REM-Schlaf in der zweiten Nachthälfte verlängert. Diese objektiven Schlafdaten entsprechen etwa der subjektiven Beurteilung der Patienten über ihren Schlaf. 4. Ein typischer l-DOPA-Effekt ist die frühe Unterdrückung von REM-Schlaf für einige Stunden (erste Nachthälfte). Bei der Patientengruppe mit geringem Therapie-Effekt wird die REM-Latenz unter l-DOPA signifikant verlängert, der prozentuale REM-Anteil in der ersten Nachthälfte verringert und in der zweiten Hälfte der Nacht im Sinne eines REM-Rebounds wieder aufgeholt. Dieser Einfluß des l-DOPA auf den REM-Schlaf und auf den cyclischen Ablauf der Stadien (Sequenzanalysen) zeigt im zeitlichen Verlauf bei späteren Ableitungen eine Gewöhnung mit verminderter Wirkung.
    Notes: Summary In 24 patients (aged 47 to 72 years) with Parkinson's disease, the influence of l-DOPA upon night sleep is investigated. In addition to the usual polygraphic EEG recordings, the EISA method of Tönnies is used. Forty recordings of night sleep show that patients with Parkinson's disease often suffer from the following sleep disturbances: 1. increased and prolonged waking periods; 2. reduction of both REM-sleep and deep-sleep; and 3. disruption of the sleep sequence. Forty additional recordings show l-DOPA to have favoable reffects on both night sleep and motor symptoms. Thus, improved rigor and akinesia are accompanied by a decrease of waking periods, an increase of synchronized and REM-sleep, and a normalized stage sequence. Furthermore, patients with little or no clinical improvement after treatment with l-DOPA also fail to show an improvement of night sleep but acquire a longer REM-stage latency. The objective data agree with the patients' subjective rating of their own improvement. An increase of REM-latency is considered to be a specific effect of l-DOPA. Increased REM-latency is accompanied by a decrease of paradoxical sleep in the first half of the night, and a REM-rebound in the second half night. This is statistically significant only in patients with minor clinical improvement. Later recordings suggest that the influence of l-DOPA on REM-sleep and sleep sequence is subject so adaptation.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 111 (1970), S. 106-126 
    ISSN: 1432-0878
    Keywords: Saccus vasculosus ; Liquor-contact neurones ; Teleost brain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Epithel des Saccus vasculosus des Flußbarsches Perca fluviatilis besteht aus Krönchenzellen, bipolaren Liquorkontaktneuronen (Zahlenverhältnis etwa 4∶1) und Stützzellen. Im Bereich des Saccus kommen Macrophagen vor. Die Krönchenzellen wurden unter verschiedenen Fixierungsbedingungen untersucht. Die Globuli enthalten schlauchförmige Zisternen, die nicht mit den Zisternen des Zellapex in Verbindung stehen. Im Zytoplasma des Zellapex und der Globuli wird bei langdauernder OsO4-Imprägnation Osmium gebunden. Die Krönchenzellen werden basal von Ausläufern der Stützzellen unterlagert. Sie werden nicht innerviert und entsenden keine Axone. Die bipolaren Neurone sind durch einen im Liquor endigenden Dendriten und ein Axon gekennzeichnet, das in eines der Faserbündel des Epithels eintritt. Der Dendrit trägt 1 bis 2 Zilien. Die Zelle ist reich an Vesikeln und kann am Perikaryon wie an den Ausläufern Synapsen tragen. Im extrazellulären Raum um die Neurone und in vesikulären Strukturen des Apex wird Acetylcholinesterase nachgewiesen. Der Nervus sacci vasculosi dürfte nur afferente Axone von Liquorkontaktneuronen und efferente Fasern, die diese innervieren, enthalten.
    Notes: Summary The epithelium of the Saccus vasculosus of Perca fluviatilis consists of coronet cells and bipolar liquor contact neurones in a 4∶1 ratio, and supporting cells. The organ also contains macrophages. The coronet cells have been studied after different kinds of fixation. The globules of these cells contain tubelike cisternae, which do not connect with cisternae in the cell's apical protrusion. The cytoplasm of the apical protrusion and to a greater extent of the globules, is stained by longlasting OsO4-impregnation. The coronet cells have no direct contact with the basement membrane of the organ. They are neither innervated nor have axons. The dendrites of the bipolar nerve cells end with a bulbous structure protruding into the cerebrospinal fluid. The dendrites contain vesicles and each bears 1–2 cilia. The axons join the fiber bundles of the epithelium. There are synaptic contacts on the surface of the neurons and their processes. In some vesicular structures within the apices and more conspicuously within the extracellular space around these cells indications of acetylcholinesterase activity are found. It appears that the nervus sacci vasculosi contains only afferent axons of the bipolar liquor-contact neurons and efferent fibres which form synaptic contacts with these neurons.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 129 (1972), S. 65-75 
    ISSN: 1432-0878
    Keywords: Fetal metanephros ; Renal nerves ; Renal tubules ; Macula densa ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung In elektronenmikroskopischen Untersuchungen an den Nachnieren 13–16 Wochen alter menschlicher Feten wird gezeigt, daß die Macula densa und andere Abschnitte des Mittelstücks der Niere von marklosen Nervenfasern innerviert werden. Nervenfasern gelangen mit den Gefäßen an die Tubuli. Synapsen finden sich innerhalb der Tubulusmembran an der Basis der Tubulusepithelien. Eine Synapse wurde an der parietalen Bowmanschen Kapsel nahe dem Gefäßpol des Glomerulus beobachtet. Die Mehrzahl der bisher am Tubulus beobachteten Axonendigungen scheint cholinergen Neuronen zuzugehören, jedoch ist eine weitere Abklärung in Verbindung mit histochemischen Methoden erforderlich. Die Bedeutung der Innervation für die Funktion des Nephron ist schwer einzuschätzen, zumal experimentelle Untersuchungen hierzu fehlen. Auch Befunde nach Nierentransplantation lassen wegen der möglichen postoperativen Persistenz und Regenerationsfähigkeit intrarenaler Nervenfasern keine eindeutigen Rückschlüsse zu. Möglicherweise ist mit dem Nachweis der Innervation auch das regulierende Agens für den „kontraktilen Apparat“ der Niere bzw. des Nephron gefunden. Interessanter weiterer Befund ist die Beobachtung synaptischer Nerv-Endothel-Kontakte in kleinsten Nierengefäßen (Endarteriolen).
    Notes: Summary Electron microscopic study of the metanephros of 13–16-week-old human fetuses shows that the region of the macula densa as well as other segments of the distal convoluted tubule are innervated by unmyelinated nerve fibers. Nerve fibers reach the tubules alongside blood vessels. Synapses are found within the basal lamina of the tubular epithelia. One synapse was seen in the parietal part of the Bowman's capsule near the vascular pole of the glomerulus. Present evidence suggests mainly cholinergic innervation of the distal tubule, but verification using other histochemical methods is necessary. In the absence of experimental studies, it is difficult to determine the functional role of the innervation of the nephron. Observations after renal transplantation are not conclusive in view of possible postoperative persistence and regeneration of intrarenal nerve fibres. It may well be that innervation controls the “contractile apparatus” of the kidney. Synaptic contacts between axons and endothelial cells of the smallest renal arterioles may also have functional significance.
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