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  • 1
    Electronic Resource
    Electronic Resource
    Die Kopfregeneration vonLineus sanguineus Rathke(Nemertini) unter dem Einfluβ von Actinomycin-D. Chemomorphologische Befunde (1971)
    Springer
    Development genes and evolution 168 (1971), S. 359-361 
    Details
    ISSN: 1432-041X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Isolierte Körperteile vonLineus sanguineus wurden in Seewasser gehalten, das unterschiedliche Konzentrationen (1,9, 0,95 und 0,48 μg/ml) von Actinomycin-D enthielt. Nach 4, 5, 6 und 10 Tagen wurden die Regenerate histologisch und histochemisch (Glykogen, Glucose-6-phosphat-Dehydrogenase und RNS) untersucht. In Abhängigkeit von der Actinomycin-D-Konzentration werden bestimmte Phasen der Regeneration gehemmt; dabei sind Proliferationsprozesse weniger empfindlich als Differenzierungsprozesse. Histochemisch werden bei Hemmung der wachstumsaktiven Areale die im Normalfall zu beobachtenden stofflichen Merkmale: Glykogeneinlagerung und nachfolgender Anstieg der G-6-P-DH-Aktivität und der RNS-Konzentration vermißt.
    Notes: Summary Fragments ofLineus sanguineus were incubated in seawater, which contained different concentrations of actinomycin-D (1.9 μg/ml, 0.95 μg/ml and 0.48 μg/ml). After 4, 5, 6 and 10 days the regenerates were studied by histological and histochemical methods (glycogen, glucose-6-phosphate-dehydrogenase and RNA). Corresponding to actinomycin-D concentration certain phases of regeneration are inhibited. The phases of proliferation are less sensitive to actinomycin-D than the phases of differentiation. If morphogenetic areas are inhibited, the normally demonstrable histochemical characteristics: accumulation of glycogen and later, the increase of G-6-P-DH activity and RNA concentration do not appear.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00582931
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  • 2
    Electronic Resource
    Electronic Resource
    Chemomorphologische Befunde (Glykogen, G-6-P-DH, RNS) am Regenerationsblastem vonLineus sanguineus Rathke (Nemertini) (1970)
    Springer
    Development genes and evolution 165 (1970), S. 285-295 
    Details
    ISSN: 1432-041X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Während der Kopfregeneration vonLineus sanguineus lassen sich zwei Phasen unterscheiden. In derProliferationsphase wird die Schnittwunde durch Epithel verschlossen, danach kommt es durch Einwanderung von Blastocyten zum Aufbau des Blastems. Im Verlauf derDifferenzierungsphase treten Anlagen auf, die sich im weiteren zu den Kopforganen ausbilden. Epidermisproliferation, Blastembildung und Organdifferenzierung (Cerebralorgane, Vorderdarm und Rüssel) sind histochemisch in gleicher Weise charakterisiert: alle diese morphogenetischen Areale zeichnen sich zunächst durch einen hohen Glykogengehalt aus, der sich während der Weiterentwicklung des Regenerats bei zunehmender G-6-P-DH-Aktivität und Anstieg der RNS-Konzentration wieder verliert. Aus diesen Befunden ist abzuleiten, daß die in morphogenetischen Arealen durch Glykogenolyse bereitgestellte Glucose über den Pentose-Phosphat-Zyklus für die Nucleinsäuresynthese verwendet wird.
    Notes: Summary The head regeneration ofLineus sanguineus consists of two periods. During the phase ofproliferation the wounds are covered with epidermis, thereafter immigrating blastocytes build up the blastema. During the phase ofdifferentiation anlagen are discernible, which subsequently become the head organs. Proliferation of epidermis, the building of blastema and the differentiation of the organs (cerebral organs, foregut and proboscis) are histochemically characterized in the same way: in the beginning there is a high glycogen content in the morphogenetic areas, which decreases during further development with increasing G-6-P-DH activity and with growing RNA concentration. These results indicate that in morphogenetic areas the glucose resulting from glycogenolysis is metabolized by the pentose-phosphate-shunt and is utilized for the synthesis of nucleic acids.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00573675
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  • 3
    Electronic Resource
    Electronic Resource
    Histamine content and release of isolated rat gastric mucosal cells (1985)
    Springer
    Inflammation research 16 (1985), S. 202-204 
    Details
    ISSN: 1420-908X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Enzymatically dispersed rat gastric cells were subdivided (Percoll®) in fractions (F1, F2, F3) with different number of parietal cells (PC) and the intracellular histamine content was estimated (ng/106 cells): F1 (9% PC): 17±4 (SEM), F2 (26% PC): 80±9 and F3 (77% PC): 134±15. Histidinedecarboxylase showed the same pattern of distribution, F1 low, F2 medium, F3 high activity. Incubated F3 cells constantly released histamine (19±3 ng/106 cells/h), a process which could be stimulated by carbachol, forskolin and hexoprenaline. The data suggest: (1) rat gastric histaminocytes copurify with PC, (2) background stimulation by histamine should be considered in isolated cell systems, (3) vagal stimulation may release histamine within the gastric mucosa.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01983139
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  • 4
    Electronic Resource
    Electronic Resource
    Die W-Sn-Lagerstätte Chojlla, Cordillera Real, Bolivien Teil 1: Nebengestein und Tektonik (1977)
    Springer
    Mineralium deposita 12 (1977), S. 247-262 
    Details
    ISSN: 1432-1866
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Description / Table of Contents: Resumen El yacimiento de wolfram y estaño de la mina Chojlla está ubicado en la Cordillera Real al Noreste de la Paz dentro de una secuencia muy potente de pizarras del Paleozoico inferior y cerca del contacto con el granito alcalino y la granodiorita del batolito Taquesi-Mururata de edad triásica superior. Debido a la intrusión, las lutitas ya levemente plegadas durante el ciclo hercínico fueron sometidas a un metamorfismo de bajo grado y a una turmalinización metasomática. Una serie de vetas mineralizadas, que están inclinadas hacia el SW, corta perpendicularmente a las pizarras inclinadas hacia el NE. Resultan de grietas de extensión, las cuales pudieron abrirse sólo por consecuencia de una orientación especial de la estratificación paralela al esfuerzo extensivo y perpendicular al esfuerzo compresivo. Estos esfuerzos pueden explicarse como componentes de un sistema de cizalla producido por un levantamiento tardío del batolito. La tectónica más reciente produjo primero frecuentes fallas en el plano de estratificación y luego un sistema tranversal de fallas inversas.
    Notes: Abstract The W, Sn ore deposit of “Mina Chojlla” is situated in the Cordillera Real to the NE of La Paz within a thick pile of Lower Paleozoic slates near the contact to the alkaligranitic and granodioritic Taquesi-Mururata Batholith of Upper Triassic age. Due to the intrusion the slates, which during the Paleozoic had slightly been folded, became low grade metamorphic and were metasomatically turmalinized. The slates, which uniformly dip to the NE, are cut at right angle by a system of parallel orebearing quartz veins, which dip to the SW. They evidently are tensional features, but opening of joints was made possible only through a special orientation of stratification parallel to the tensional stress and normal to the compressional stress. The stress pattern was generated in a shear zone as a consequence of an upward motion of the batholith with respect to its surroundings. Younger Andean tectonics first caused frequently repeated small bedding plane faults, and lateron a system of reversed faults.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00206165
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  • 5
    Electronic Resource
    Electronic Resource
    Evolutionary cycles during the Andean orogeny: repeated slab breakoff and flat subduction? (2002)
    Malden USA : Blackwell Science Ltd
    Terra nova 14 (2002), S. 0 
    Details
    ISSN: 1365-3121
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences
    Notes: Tectonomagmatic similarities between the modern Chilean flat-slab region and pre-Neogene magmatic episodes suggest that they represent analogues to flat subduction. Evolutionary patterns in each magmatic suite include (i) increasing La/Yb ratios and Sr-and Nd-isotopic enrichment through time, (ii) eastward-migration of magmatism after periods of transpressional/transtensional intra-arc deformation, and (iii) subsequent termination and virtual absence of main-arc activity for 5–10 Myr. These patterns may reflect slab shallowing followed by flat subduction and thickening of the overlying crust. If repeated, they require interchanging episodes of slab steepening. Increasing convergence rates force slab kinking and eventual failure of the oversteepened slab, followed by rebound of the slab tip (owing to lack of further slab pull), flat subduction and termination of subduction-related magmatism. Rapid subduction leads to shallow overriding of the detached slab fragment. Eclogitization of the gradually steepening slab tip at depth and subsequent slab pull permits asthenospheric corner flow and subduction-related magmatism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-3121.2002.00387.x
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  • 6
    Electronic Resource
    Electronic Resource
    Die Stratigraphische Einordnung der Ophiolithe des Nordapennins (1964)
    Springer
    International journal of earth sciences 53 (1964), S. 358-375 
    Details
    ISSN: 1437-3262
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Description / Table of Contents: Abstract Northern Apennitie Ophiolites are subdivided by their age. North of Genoa and along the coast between Sestri Levante and Levanto only, the rocks are Upper Jurassic or Lowest Cretaceous of age; the remaining area shows an Upper Albian to Lower Turonian age of ophiolithes.
    Abstract: Résumé Les ophiolites des Apennins septentrionaux sont, suivant leur âge, subdivisés en différents groupes. C'est seulement dans la région au Nord de Gênes et le long de la bande côtière entre Sestri Levante et Levanto que se vérifie pour les ophiolites l'ancienne conception d'un âge allant du Jurassique supérieur à la base du Crétacé inférieur. Dans le territoire restant on peut attribuer à certains affleurements un âge notablement plus récent (Albien supérieur jusqu'au Turonvien inférieur). Pour fixer cet âge, on s'est appuyé sur les brèches qui accompagnent la plupart des ophiolites; ces brèches ont été décrites et subdivisées en quelques types.
    Notes: Zusammenfassung Die Ophiolithe des Nordapennins werden nach ihrem Alter in verschiedene Gruppen eingeteilt. Nur im Gebiet nördlich von Genua und längs des Küstenstreifens zwischen Sestri Levante und Levanto läßt sich die alte Anschauung eines oberjurassischen bis tief unterkretazischen Alters der Ophiolithe rechtfertigen. In dem noch verbleibenden Gebiet konnte für einzelne Vorkommen ein wesentlich jüngeres Alter (O.-Alb bis U.-Turon) wahrscheinlich gemacht werden. Von Bedeutung für diese Alterseinstufungen waren die fast alle Ophiolithvorkommen begleitenden Brekzien, die in einzelnen Typen untergliedert und beschrieben werden.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02040756
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  • 7
    Electronic Resource
    Electronic Resource
    Negative Inotropie von endogenem Acetylcholin beim Katzen- und Hühnerventrikelmyokard (1972)
    Springer
    Pflügers Archiv 333 (1972), S. 35-50 
    Details
    ISSN: 1432-2013
    Keywords: Mammalian Ventricular Myocardium ; Cholinergic Innervation ; Endogenous Acetylcholine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effect of endogenous acetylcholine (ACh) on the isometric force of contraction has been investigated on 40 papillary muscles of the cat right ventricle and on 20 strips of the chicken right ventricle. ACh was released from intramural cholinergic nerve endings by high voltage stimulation and simultaneous application of trains of stimuli during the absolute refractory period of the myocardium. In the pharmacologically untreated heart muscle the negative inotropic effect of sndogenous ACh was generally superimposed on the positive inotropic effect of simultaneously released catecholamines. During trains of high voltage stimuli, cat papillary muscles pretreated with reserpine showed a significant reduction in amplitude (average 19%) only if contractility had been increased by previous application of noradrenaline or isoprenaline. With guanethidine pretreatment high voltage stimulation reduced the amplitude significantly by 34%. In ventricular myocardium of chicken the negative inotropic effect of endogenous ACh was more impressive even in the absence of an increased contractility due to catecholamines. It is concluded from the following findings, that the negative inotropic substance is ACh: the negative inotropic effect was intensified by neostigmine and prevented by atropine; liquid, sampled from the bath during trains of high voltage stimuli was able to induce a contracture of frog rectus; under trains of high voltage stimuli the radio-activity in the perfusion liquid of preparations, pretreated with ratio-active ACh, was increased during the wash-out period. Moreover, the existence of cholinergic nerve fibers could be detected in cat papillary muscles as well as in chicken heart preparations by means of histochemical identification.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00586040
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  • 8
    Electronic Resource
    Electronic Resource
    Histologische und spektralphotometrische Untersuchungen zur Bestimmung der „Stärke der Metachromotropie“ mit Dichlorpseudoisocyanin (1970)
    Springer
    Histochemistry and cell biology 24 (1970), S. 187-196 
    Details
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Dichlorpseudoisocyanin (DPI) wurde hinsichtlich seines metachromatischen Verhaltens in vitro spektralphotometrisch geprüft. Nach Zugabe eines der Substrate Heparin, Chondroitinsulfat oder Polyron bildet sich im Bereich von 585–600 nm eine metachromatische Absorptionsbande aus. Diese wird durch Wasserstoffionen, Neutralsalze, Alkohol sowie Farbstoffverdünnung unterdrückt. In diesbezüglichen Testreihen erweist sich der DPI-Heparin-Komplex als wesentlich resistenter als ein entsprechender DPI-Chondroitinsulfatoder DPI-Polyron-Komplex. In analog angelegten Testreihen am histologischen Schnitt konnte gezeigt werden, daß die einzelnen sauren Gewebskomponenten gegenüber DPI eine unterschiedliche Stärke der Metachromotropie haben. Als am stärksten resistent gegen Störfaktoren erweisen sich die Heparin enthaltenden Mastzellen, gefolgt von Knorpelgrundsubstanz und Drüsenschleim. Die DPI-Metachromasie eignet sich gut zur Klassifizierung saurer Gewebskomponenten aufgrund der unterschiedlichen Stärke der Metachromotropie. Ihr Vorteil gegenüber der Toluidinblau- oder Acridinorange-Metachromasie liegt vor allem darin, daß die mit Dichlorpseudoisocyanin metachromatisch gefärbten Gewebskomponenten unter Verwendung eines Linienfilters (579 nm) auch im Schwarzweiß-Bild einwandfrei dokumentiert werden können.
    Notes: Summary Dichlorpseudoisocyanine (DPI) was tested in vitro spectrophotometrically in view of its metachromatic effects. After the addition of one of the substrates heparin, chondroitin sulfate or polyron a marked metachromatic maximum is noted near 585–600 nm. This metachromatic absorption band is depressed by H+-ions, neutral salts, alcohol and the dilution of the dye-stuff. In test series it was shown that in this respect the DPI-heparincomplex is much more resistant than the complexes with chondroitin sulfate or polyron. Histological preparations in analogical test series showed that various acid components of the tissue possess a different “strength of metachromotropy” against DPI. Mast cells containing heparin proved most resistant against factors irritating metachromasia; they are followed by cartilage ground substance and glandular mucins. DPI-metachromasia is a valuable test to classify different acid tissue components with regard to their “strength of metachromotropy”. The advantage of this method in comparison with toluidine blue or acridine orange metachromasia is, that tissue components stained metachromatically with dichlorpseudoisocyanine may be documented successfully in black and white photographs by the use of a line filter (579 nm).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00277611
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  • 9
    Electronic Resource
    Electronic Resource
    Lectin histochemistry on mucous substances of the taste buds and adjacent epithelia of different vertebrates (1988)
    Springer
    Histochemistry and cell biology 88 (1988), S. 453-461 
    Details
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the present study carbohydrate residues in taste buds (TBs) and adjacent epithelial formations of a teleostean fish, a frog and the rabbit were detected by means of lectin histochemistry. Biotinylated lectins fromPisum sativum (PSA),Arachis hypogaea (PNA),Dolichos biflorus (DBA),Triticum vulgaris (WGA and succinylated WGA),Glycine max (SBA) andUlex europaeus (UEA I) have been applied. The lectins were bound to an avidin-biotin-peroxidase-complex (ABC) and visualized by diaminobenzidine/ H2O2. Most intensive reactivity was observed at the taste dise cells of the frog with DBA, S-WGA and SBA. PNA did not bind to the TBs of any of the animals tested. As shown in SBA preparations, sialic acid is present in a nonacylated and an acylated form in the mucosa of the frog's tongue. The TBs of the fish possess all the sugars we looked for except for the disaccharided-galactose-(1–3)-β-d-N-acetyl-galactosamine (Gal/GalNAc) and sialic acid. The TBs of the rabbit contain GalNAc, as detected with DBA, but not with SBA; and fucose (Fuc), mannose (Man) andN-acetyl-glucosamine (GlcNAc). As revealed by preincubation of the tissue sections with neuraminidase in TB cells of the rabbit, sialic acid masks Gal/GalNAc and GalNAc. These lectin-binding characteristics show that in the TBs of some selected representatives which belong to different vertebrate classes exist different mucous substances. These substances possess different binding characteristics to specific sugars, and this is possibly of particular interest to chemoreception phenomena.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00570308
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  • 10
    Electronic Resource
    Electronic Resource
    Electron microscopic demonstration of lectin binding sites in the taste buds of the European catfish Silurus glanis (Teleostei) (1990)
    Springer
    Histochemistry and cell biology 94 (1990), S. 617-628 
    Details
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Taste buds in the European catfish Silurus glanis were examined with electron microscopic lectin histochemistry. For detection of carbohydrate residues in sensory cells and adjacent epithelial cells, gold-, ferritin-and biotin-labeled lectins were used. A post-embedding procedure carried out on tissue sections embedded in LR-White was applied to differentiate between the sensory cells: The lectins from Helix pomatia (HPA) and Triticum vulgare (WGA) bound to N- acetyl-galactosamine and to N-acetylglucosamine residues occurring especially in vesicles of dark sensory cells. This indicates a secretory function of these cells. Most light sensory cells — with some exceptions, probably immature cells —, are HPA-negative. The mucus of the receptor field and at the top of the adjacent epithelial cells was strongly HPA-positive. Pre-embedding studies were performed in order to obtain information about the reaction of the mucus with lectins under supravital conditions. The mucus of the taste bud receptor field exhibited intensive binding to WGA, but not to the other lectins tested. Most lectins bound predominantly to the surface mucus of the nonsensory epithelium and to the marginal cells close to the receptor field. The strong lectin binding to mucins and the relatively weak lectin binding to cell surface membranes in pre-embedding studies suggest that the mucus possibly serves as a barrier which is passed selectively only by a small amount of lectins or lectincarbohydrate complexes. Lectin-carbohydrate interactions may play a role in recognition phenomena on the plasmalemmata of the taste bud sensory cells. Recognition processes directed to bacteria or viruses should be considered as well.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00271989
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