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  • 1970-1974  (2,255)
  • 1945-1949  (1,208)
  • 1890-1899  (195)
  • Cell & Developmental Biology  (3,546)
  • Best. von Eisen(III)
  • Chromatographie, Dünnschicht
  • Spektralphotometrie
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Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 102-108 
    ISSN: 1618-2650
    Keywords: Zinkstaubdestillation ; Ultramikrobereich, Apparatur, TAS-Verfahren. Thermofraktographie, TAS-Verfahren ; Chromatographie, Dünnschicht ; Zinkstaubdestillation, Ultramikrobereich. Analyse von Naphthalinderivaten, Anthracenderivaten, Phenanthrenderivaten, Tetracenderivaten, Indolderivaten ; Chromatographie, Dünnschicht ; Zinkstaubdestillation, TAS-Verfahren
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird eine Methode beschrieben, die es erlaubt, unter kontrollierten Bedingungen mit 20–200 μg Ausgangsmaterial eine Zinkstaubdestillation durchzuführen. Hierzu wird die Probe auf Cu-aktiviertes Zink in einer TAS-Patrone für einige Minuten auf 350–450° C erhitzt. Die dabei entstehenden sauerstofffreien Aromaten bzw. stabilen Heterocyclen werden durch einen Stickstoffstrom von 15 ml/min direkt auf den Startpunkt einer DC-Schicht transferiert. Anschließend wird chromatographiert und die auftretenden Reaktionsprodukte werden identifiziert. Zum Studium der Reaktionsvorgänge und der optimalen Temperaturbereiche dient die Thermofraktographie. Es sind Anwendungsbeispiele aus der Gruppe der Naphthalin-,Anthracen-, Phenanthren-, Tetracen- und Indolderivate gegeben.
    Notes: Abstract A method for zinc dust distillation of 20–200 μg of substance under controlled conditions is described. The sample is heated on copper-activated zinc up to 350–450° C for several minutes in a TAS-cartridge. The resulting oxygen-free aromatic resp. the stable heterocyclic components are transferred directly to the starting point of a TLC-plate by a stream of nitrogen at 15 ml/min and identified after chromatography. Thermography is applied to study the reaction process and to determine the optimal temperature ranges. Examples of application to the groups of naphthalene-, anthracene-, phenanthrene-,tetracene- and indol derivatives are listed.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 126-127 
    ISSN: 1618-2650
    Keywords: Chromatographie, Dünnschicht ; Rückgewinnung geringer Substanzen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 119-123 
    ISSN: 1618-2650
    Keywords: Best. von 8-Hydroxychinolinderivaten, 8-Hydroxychinaldinderivaten in Pharmazeut. Produkten ; Chromatographie, Dünnschicht ; ÄDTA-behand. Platten
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird eine Methode beschrieben, mit der 8-Hydroxychinolin- und 8-Hydroxychinaldin-Derivate nach erfolgter Entwicklung auf Kieselgelplatten direkt quantitativ mit einem Chromatogramm-Spektralphotometer bestimmt werden können. Durch Vorbehandlung der Platten mit Komplexbildnern, wie Äthylendiamintetraessigsäure, Diäthylentriaminpentaessigsäure oder Triäthylentetraminhexaessigsäure, wird im Gegensatz zur unbehandelten Platte erreicht, daß die Substanzen runde Flecken ausbilden, die zur quantitativen Bestimmung geeignet sind. Die Methode hat sich auch bei der Bestimmung der Wirkstoffe aus Arzneiformen, wie Dragees und Salben, bewährt und läßt sich mit einer maximalen relativen Standardabweichung von ± 3,4% gut reproduzieren.
    Notes: Abstract A method is described allowing direct quantitative determination of 8-hydroxyquinoline and 8-hydroxyquinaldine derivatives with a chromatogram spectrophotometer after development on silicagel plates. In contrast to untreated plates, pretreatment of the plates with complexing agents like ethylene-diamine-tetraacetic acid, diethylenetriamine-pentaacetic acid, or triethylenetetramine-hexaacetic acid, results in formation by the compounds of round areals which are suitable for quantitative measurement. This method proved also valuable for the quantitative measurement of the active contents of pharmaceutical formulations, like tablets or ointments. It is reproducible with a maximal relative standard deviation of ± 3.4%.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 124-126 
    ISSN: 1618-2650
    Keywords: Trenn. von Pesticiden, phosphorhaltig ; Chromatographie, Dünnschicht ; Schicht aus bas. Zinkcarbonat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Dünnschichten von basischem Zinkcarbonat eignen sich zur Trennung von Insecticiden aus der Gruppe der Organophosphorsäuren. Mit Petroläther/Aceton-Gemischen zwischen 98∶2–86∶14 werden günstige Rf-Werte und gute Fleckzeichnungen erreicht. Die Substanzen sind entweder im kurzwelligen UV-Licht zu erkennen, wenn man der Dünnschicht Fluorescenz-Indicator F 254 der Fa. Merck zusetzt, oder aber im Tageslicht nach Sprühen mit Pd(II)Cl2-Lösung, wobei rotbraune Flecken entstehen. Die Wirkstoffe lassen sich mit Aceton quantitativ eluieren; Die Trennung kann auch säulen-chromatographisch durchgeführt werden. Die Trenneffekte sind ähnlich denjenigen, wie sie auf Kieselgel erreicht werden. Das basische Zinkcarbonat hat aber den Vorteil geringerer chemischer Aktivität, so daß weniger Artefakte entstehen.
    Notes: Abstract Thin layers of basic zinc carbonate can be used with good results to separate organophosphorous pesticides. With a petroleumether/acetone mixture (between 98∶2 and 86∶14) good Rf-values and clearly defined spots are obtained. The substances are either recognizable in short-wave UV-light, when the fluorescence indicator F 254 from Fa. Merck is added to the thin layer, or in day-light, after having been sprayed with a solution of Pd(II)Cl2, which leads to the formation of reddish-brown spots. The pesticides can be eluted quantitatively with acetone; the separation can also be carried out by means of column chromatography. The effects of separation are similar to those obtained on silica gel, but basic zinc carbonate has the advantage of lower chemical activity, which means that less artifacts are formed.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1618-2650
    Keywords: Best. von Val5-Angiotensin II Asp1-β-amid, Hypertensin, Peptidhormone ; Spektralphotometrie ; Azokupplung mit Halogenbenzoldiazoniumsalz
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Am Beispiel des Octapeptids Val5-Angiotensin II Asp1-β-amid (Hypertensin-CIBA) wird die Möglichkeit aufgezeigt, Polypeptidhormone mit Tyrosin und/oder Histidin im Molekül über eine Kupplung mit p-halogensubstituierten Benzol-diazoniumsalzen quantitativ zu erfassen. Durch photometrische Bestimmung des Kupplungsprodukts konnten noch 1–2 nMol Hypertensin nachgewiesen werden. Eine Steigerung der Empfindlichkeit läßt sich durch Kupplung des Polypeptids mit radioaktiv markierten Diazoniumsalzen erreichen. Die als besonders günstig ermittelten Bedingungen für die Diazotierungs- und Kupplungsreaktionen werden mitgeteilt. Das Kupplungsprodukt war papier-chromatographisch einheitlich. Es handelt sich vermutlich um eine Monoazoverbindung. Unter den gewählten Bedingungen stellt sehr wahrscheinlich Tyrosin den kupplungsfähigen Aminosäurerest im Hypertensinmolekül dar.
    Notes: Abstract Through the azocoupling of Val5-angiotensin II-Asp1-β-amide (Hypertensin-CIBA) with p-halogene substituted benzenediazonium salts the possibility is shown for quantitative determination of polypeptides containing tyrosine and/or histidine. 1 to 2 nanomoles of the coupling-product could be measured photometrically. The detection limit can be lowered, if the polypeptide is coupled with a radioactive labelled diazonium salt. The preferable reaction conditions for diazotising and coupling are reported. The reaction-product showed an uniform behaviour in the used paper-chromatographic system. Probably it is a monoazo compound. Under the chosen conditions the tyrosyl group is very likely the reacting part of the hypertensin molecule.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Fresenius' Zeitschrift für analytische Chemie 269 (1974), S. 125-126 
    ISSN: 1618-2650
    Keywords: Nachw. von Xylenolen, Dimethylphenolen ; Chromatographie, Dünnschicht ; versch. Schichten u. Reagentien
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1618-2650
    Keywords: Nachw. von Kresolen, Phenol ; Chromatographie, Dünnschicht ; versch. Schichten und Reagentien
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 142 (1974), S. 411-431 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Cells in secretory glands of globiferous pedicellariae from Strongylocentrotus purpuratus (Stimpson) were studied with the electron microscope and subjected to preliminary light microscopic, histochemical analysis. Specimens for electron microscopic observation were fixed with chilled 2% glutaraldehyde in sea water postfixed in cold 1.33% osmic acid, and embedded in Araldite 502 epoxy resin Samples for histochemical analysis were fixed in the same manner, and then embedded in n-butylmethacrylate.Secretory cells line and fill partially bifurcated, muscular gland sacs located peripherally on each of three jaw elements comprising the pedicellarial head. Cells from venom glands are typically mucoid in appearance, possessing small volumes of basally displaced, vesiculated cytoplasm and an extensive system of vacuoles dominating the apical nine-tenths of each cell. These vacuoles enclose ground substances of various densities and staining affinities. Despite their extensive vacuolation, gland cells contain numerous cytomembrane complexes indicating metabolic activity just prior to fixation. Deciduous endoplasmic reticulum, Golgi complexes, large vacuoles, and various species of vesicles associated with these membrane systems are found in spatial proximity which indicates an apparent biosynthetic association.Preliminary histochemical tests on sections embedded in acrylic plastic indicate vacuolar products may consist of protein and nonsulfated acid mucosubstances.Gland cells are probably holocrine in function, releasing their vacuolar complement upon constriction of the muscular gland sac. There is no evidence indicating delivery of non-membrane bounded, granular secretion to an acellular lumen within the gland sac.
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  • 9
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Transmission and scanning electron microscopic studies demonstrate the stimulatory effect of synthetic salmon calcitonin on the fine structure of fibroblasts and on collagen formation in cutaneous wounds experimentally induced in rabbits. Long-term administration of calcitonin enhances fibroblast growth and collagen synthesis. The fibroblasts hypertrophy and exhibit a highly developed rough endoplasmic reticulum (RER), several polyribosomes, large nuclei, hypertrophic Golgi complex, and many dense granules and lysosomes. Mitochondria are elongate and ramify; intracellular as well as extracellular synthesis of collagen increases. Fibrils appear tightly packed, in large heaps or spicula, with a characteristic periodicity and striation.Scanning electron micrographs of topography and relationships with collagen fibers and fibrils and cells surface changes demonstrate an extensive network of fine fibrils between collagen fibers, marked ruffling of cell membranes as well as numerous blebs on the cell surface. The latter are significant in collagen formation and egestion.
    Additional Material: 2 Tab.
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  • 10
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Sperm enter the anterior vas deferens individually in the spider crab male. There they become surrounded by secretion products from the cells of the vas deferens, and are compartmentalized into spermatophores of varying size. The anterior vas deferens can be divided into three regions. The epithelium of the anterior vas deferens varies regionally from low to high columnar. The cytoplasm contains vast arrays of rough endoplasmic reticulum and Golgi complexes but few mitochondria. Intercellular spaces contain septate junctions, gap junctions and vesicles.Once the spermatophores have been formed in the anterior vas deferens, they are moved posteriorly to the middle vas deferens where they are stored and surrounded by seminal fluids. The epithelial cells of the middle vas deferens contain large amounts of rough endoplasmic reticulum and Golgi complexes. Numerous micropinocytotic vesicles appear, forming at the cell surface and within the apical cytoplasm. Their suggested function is the resorption of secretion products of the anterior vas deferens which initiated compartmentalization of the spermatozoa into spermatophores.The posterior vas deferens functions primarily as a storage center for spermatophores until they are released at the time of copulation. Seminal fluid surrounding the spermatophores is produced in this region as well as in the middle vas deferens. The cells of this region contain vast arrays of vesicular rough endoplasmic reticulum and Golgi complexes. The cells are multinucleate. Microtubules are numerous throughout the length of the cells and appear to insert on the plasma membrane.
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  • 11
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 143 (1974), S. 21-75 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Basicranial anatomy of mammalian carnivores is significant in the determination of carnivore evolution. One of the least understood yet most often studied features of the basicranium is the auditory bulla, a bony capsule enclosing the middle ear. Although previously believed to be formed by a tympanic bone alone, or by tympanic and entotympanic, it is shown here that the carnivore bulla is formed by three and in some cases four ontogenetic elements: tympanic, rostral entotympanic, caudal entotympanic(s). These elements in Carnivora appear to correspond to bulla elements discovered over 50 years ago by Van der Klaauw in representative species of several other orders of mammals.Increased auditory sensitivity appears to have been attained in various carnivore lineages by increase in the volume of the middle ear cavity, principally by hypertrophy of the caudal entotympanic, but also by different yet less common anatomical strategies such as invasion of the mastoid bone by the middle ear space. Five basic types of bulla among living Carnivora can be recognized, based largely on the relationship of the caudal entotympanic to the other bulla elements.Closely associated with the bulla in the auditory region are the median and promontory branches of the internal carotid artery. These branches exhibit a precise relationship to the bulla elements, particularly the rostral entotympanic. The promontory branch is much reduced or completely lacking in all living carnivores. Reduction or loss of the median branch is explained as the result of the development of arterial retia on the anastomotic artery in the orbital region. Reduction of the median branch is particularly characteristic of the aeluroid Carnivora, in which a greater proportion of the cerebral blood supply passes to the brain in the external carotid artery via the anastomotic branch, and is cooled in the orbital region by a countercurrent heat exchange mechanism formed by arterial retia closely associated with venous blood in surrounding sinuses. The arctoid and cynoid Carnivora are characterized by only rudimentary development of retia along the anastomotic artery, and the median branch is much better developed than in the aeluroids. Among arctoids, ursids parallel the aeluroids in the development of a countercurrent mechanism but employ the median branch of the internal carotid rather than the anastomotic branch of the external carotid artery.Bulla structure and nature of the carotid circulation in the auditory region can be determined from fossil Carnivora as well as for living forms. This study attempts to define basicranial anatomical patterns characteristic of living Carnivora which then can be used to trace the evolution of lineages in the fossil record.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 12
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 143 (1974), S. 77-105 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The termite gut flagellates are of interest because of their unusual motile organelles, their ability to digest cellulose, and their symbiotic relationship with prokaryotes inhabiting the insect gut. This report provides a detailed ultrastructural description of Pyrsonympha from the hind-gut of Reticulitermes flavipes.The motile axostyle is composed of 2,000-4,000 microtubules connected by cross-bridges. At its anterior end, the axostyle is associated with a “primary row” of microtubules which is associated with a fibrous network. The “primary row” is embedded in a large mass of amorphous, electron-dense material occupying the furthest anterior end of the cell. The basal bodies of the eight flagella are also embedded in this presumptive microtubule-organizing center. The flagella are associated with the cell surface throughout their length. Isolation and reactivation of the axostyle has demonstrated that although ATP dependent motility is inherent in the structure of the axostyle, its proper control may be mediated by the attachment of the axostyle to structures at the anterior end of the cell.Pyrsonympha lacks morphologically distinguishable mitochondria and Golgi complexes. The cell surface is covered by unique, previously underscribed, tubular specializations. Symbiotic microorganisms are observed associated with the cell surface and within the cytoplasm.Wood particles are taken up from the gut fluid by large phagocytic vacuoles formed at the posterior end of the cell. Even during the process of breakdown, the wood is always enclosed within the membrane of the phagocytic vacuole.The Pyrsonympha from Reticulitermes flavipes are not attached to the lining of the hind-gut and do not contain an attachment organelle, unlike the Pyrsonympha from other species of Reticulitermes.
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  • 13
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 143 (1974) 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
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  • 14
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 143 (1974) 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
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  • 15
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 143 (1974), S. 121-165 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The gecko ear was studied in 36 species belonging to 24 genera. This receptor has attained an advanced level of structure and performance in this group of lizards, but there are many variations among species. To a large extent these variations follow subfamily lines as represented in Kluge's system of classification.Brief consideration is given to features of the outer and middle ear, but chief concern is with inner ear structures and their relations to auditory sensitivity as represented by the cochlear potentials.The auditory papilla is segmented, with a dorsal portion whose hair cells have their ciliary tufts attached to a tectorial membrane, and a ventral portion in which these cells form tow assemblages, one with tectorial connections and the other with connections to a line of sallets.The dorsal segment varies greatly in length and in the form of ciliary orientation. In Eublepharinae and most Gekkoninae the ciliary orientation is unidirectional, and the degree of sensitivity relates to the length of this segment. In Diplodactylinae and Sphaerodactylinae the orientation is bidirectional, and this segment functionally hardly differs from the ventral segment.Auditory sensitivity as measured in terms of the cochlear potentials shows close relations with subfamily groupings, except for the Gekkoninae in which considerable diversity is found.The evidence from structural differentiation, along with that derived from the forms of the cochlear potential functions, leads to the suggestion that these ears possess a high degree of pitch discrimination and capability for the analysis of complex sounds.
    Additional Material: 25 Ill.
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  • 16
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Mature mouse and cat peripheral nerve fibers have been examined in vitro by time-lapse photography. Some Schmidt-Lanterman clefts which were open at the start closed later; other were seen to open and then to close, some of them more than once. The implications of these movements are considered, especially in regard to the question of the passage of materials from the endoneurial connective tissue spaces to the axon.Myelin movements other than those occurring at the Schmidt-Lanterman clefts consisted primarily of the development and frequent regression of indentations of the myelin sheath. A single evagination was seen to develop and then to recede. These myelin movements suggest that previously described invaginations and evaginations of the myelin sheath, including flaps of “redundant myelin”, are not static but rather that they are in a state of movement, forming and regressing at intervals.The possible functional significance of the development and regression of myelin sheath indentations in relationship to axoplasmic flow is discussed.
    Additional Material: 2 Ill.
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  • 17
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 143 (1974), S. 187-245 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The authors describe the spermiogenesis of Polyxenus lagurus, a diplopod, in the male genital ducts and the transformations the spermatozoon successively undergoes in the spermatheca.The spermatozoon in the male genital ducts looks like a little barrel devoid of centriole and of any kind of rudimentary flagellum whatever. The organelles are markedly modified; cross sections present an elongated, flattened nucleus, an X-shaped body running parallel to it on the opposite side and two longitudinal mitochondrial strips interposed between them. The rest of this barrel-shaped spermatozoon is filled with peculiar Golgi formations, the spongy chambers, which open outwards through little vents.In the spermatheca the spermatozoon is quite different: it is shaped like a long ribbon. The basic structure of the spermatozoon is formed by the double folding of part of the cortical layer of the barrel-shaped spermatozoon. On the central part of this endo-skeleton are longitudinally ranged the nucleus and the acrosome flanked on both sides by a thread of mitochondria. Even in this phase the sperm has no flagellum.
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  • 18
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 143 (1974), S. 247-257 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Several secretory and nonsecretory enzymes were localized histochemically in the main venom gland of 13 viperid snakes. All secretory cells show the intracellular oxidative enzymes succinate dehydrogenase and monoamine oxidase. The granular reactions obtained for both enzymes resemble mitochondria in distribution. Distinctive cells with a very high succinate dehydrogenase activity are dispersed among the secretory cells of all species except Atractaspis.Nonspecific acid phosphatase activity is found in the supranuclear region of the secretory cells in species that do not secrete this enzyme and throughout the cytoplasm in snakes that secrete the enzyme. Nonspecific alkaline phosphatase activity occurs in the secretory cells of those snakes whose venom shows this activity. Leucine amino peptidase (aryl amidase) activity is found in the venom and in the secretory cells of all the species.In Vipera palaestinae both the venom and the secretory cells of the main venom gland contain nonspecific esterase, L-amino acid oxidase and phosphodiesterase activities. The localization of phosphodiesterase and L-amino acid oxidase do not show major differences between glands at different intervals from an initial milking.Adenosine-monophosphate phosphatase activity is localized in the supranuclear region of the secretory cells in the glands of Vipera palaestinae and Aspis cerastes. Its activity is found in the venom of Aspis only.
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  • 19
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 143 (1974), S. 285-305 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The three dorsal ocelli of worker honeybees have been studied by light and electron microscopy. Each ocellus has a single flattened spheroidal lens and about 800 elongated retinular cells. Retinular cells are paired and form a two-part plate-like rhabdom between their distal processes. Each rhabdomere comprises parallel microvilli projecting laterally from the apposed retinular cells. Primary receptor cell axons synapse within the ocellus with ocellar nerve fibers of two different calibers. Each ocellus has eight thick fibers ca 10 m̈m in diameter and several thinner ones less than 3 m̈m in diameter. Fine structural evidence suggests that retinular axons end presynaptically on both types of ocellar nerve fibers. Since all retinular cells apparently synapse repeatedly with the thick fibers this involves a convergence of about 100:1. Thick fibers always terminate postsynaptically within the ocellus while thin fibers terminate presynaptically on other thin fibers, thick fibers or retinular axons. Structural evidence for synaptic polarization indicates that retinular cells and thick fibers are afferent, thin fibers efferent. Thus complex processing of the ocellar visual input can occur before the secondary neurons of the three ocelli converge to form the single short ocellar nerve which runs to the posterior forebrain.
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  • 20
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 143 (1974), S. 307-335 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The functional morphology of the forelimbs of the following African Viverridae was studied, Atilax paludinosus, Bdeogale crassicauda, Civettictis civetta, Genetta genetta, G. tigrina, Helogale parvula, Herpestes ichneumon, H. sanguineus, Ichneumia albicauda, Mungos mungo, Nandinia binotata. Their locomotory behaviour has been previously studied and described and is related to morphological differences. The osteology of all the species and the myology of three species is described. The species have been assigned to primary locomotor categories on the basis of their locomotion. These are 1, climbing, arboreal walking; 2, arboreal and terrestrial walking and jumping; 3, general terrestrial walking and scrambling; and 4, trotting. In the climbing arboreal walking category the most distinctive morphological adaptations are powerful flexors and extensors as well as a flexible plantigrade manus with retractile claws. In the arboreal and terrestrial walking category the shoulder, elbow and carpal joints are flexible and the manus has retractile claws, though the flexor and extensor musculature is insufficiently developed for controlled climbing. The trotting category is characterised by a high humero-radial index and a rigid antibrachium. The foot is digitigrade with the claws short and stout. Species in the general walking and scrambling category show many differences in the morphology of their feet, even though the proximal parts of the forelimb appear similar. Due to the restricted nature of the adaptations, these species have been assigned to secondary locomotor categories. Morphological characters typical of the locomotor categories are summarized in the discussion.
    Additional Material: 16 Ill.
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  • 21
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 142 (1974), S. 285-299 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The gastric mucosa of both the echidna and platypus is aglandular and the lining epithelium is stratified squamous. The latter exhibits three principle layers: stratum germinativum, stratum spinosum, and stratum corneum. The cytoplasm of cells composing the first two strata of both species shows bundles of tonofibrils and numerous free ribosomes. Cells of the stratum spinosum in the platypus also show numerous dense granules limited to the peripheral cytoplasm. The stratum spinosum of both species is comprised of fusiform-shaped cells whose adjacent cell membranes show extensive interlocking. The stratum spinosum of the echidna in addition shows numerous intercellular bridges. Cells of the stratum corneum become flattened and elongate and in the echidna nuclei near the surface appear to degenerate. Cells comprising the stratum corneum of the platypus exhibit well preserved nuclei and contain scattered large granules of varying electron density. Prior to sloughing, cells near the surface of both species show a separation of adjacent cell membranes. True keratinization is not found in the gastric lining epithelium of either species and the epithelium lining of the stomach of the echidna more closely represents a form of parakeratosis. Delicate papillae containing capillaries extend considerable distances into the overlying epithelium of both species and are thought to contribute to its nutrition.
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  • 22
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    Journal of Morphology 142 (1974), S. 301-319 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The epidermis of Eisenia is covered by a cuticle and rests on a basement lamella. The cuticle, which is resistant to a variety of enzymes, is composed of non-striated, bundles of probable collagen fibers that are orthogonally oriented and are embedded in a proteoglycan matrix. The basement lamella consists of striated collagen fibers with a 560 Å major periodicity. Proximity and morphology suggest that the epidermis may contribute to both the cuticle and the basement lamella  -  that is, the single tissue may synthesize at least two types of collagen. The epidermis is a pseudostratified epithelium containing three major cell types (columnar, basal and gland) and a rare fourth type with apical cilia. The esophagus is lined by a simple cuticulated epithelium composed predominantly of a single cell type, which resembles the epidermal columnar cell. Rare gland cells occur in the esophageal epithelium, but basal cells are lacking.
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  • 23
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    Journal of Morphology 142 (1974) 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
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  • 24
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    Journal of Morphology 144 (1974), S. 143-165 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The cuticle of five species of Oligochaeta, chosen to represent differences in size and a variety of biotopes, was studied electron microscopically after fixation with the acrolein-TAPO-osmium tetroxide method. Five distinct layers in the cuticle of all studied species were found. Staining with lead and uranyl ions or with silver proteinate visualized basically the same structural components of the cuticle, but the degree of electron opacity and the distribution of the electron-opaque stain in these components differed according to the staining method used. Since the acrolein-TAPO-osmium tetroxide method visualized the cuticular zones preferentially stained by Thiéry's silver proteinate method, it was concluded that the TAPO method may be considered suitable for the visualization of polysaccharides. Staining with phosphotungstic acid provided some information on the composition of the cuticle of Oligochaeta not obtained by staining ultrathin sections with lead and uranyl ions nor with silver proteinate. The conclusion is that phosphotungstic acid binds to polysaccharides which do not contain vicglycol groups nor active sites responsible for the positive reaction with lead and uranyl salts. Structural components in the cuticle of the oligochaetes studied were characteristic for each species. The taxonomic value of such components, however, must be confirmed by examination of a larger number of species of oligochaetes.
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  • 25
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Laboratory-reared outgrowths of the freshwater sponge Corvomeyenia carolinensis Harrison were examined using histological and histochemical techniques, supplemented by phase contrast observations of cellular behavior. The tissue and cellular components of the spongillid outgrowth region were defined in terms of function and morphogenic state. Archeocytes differ considderably, in both histochemical and morphological characteristics, from other cell types of the adult sponge, being histochemically similar to stem cells reported from a variety of developmental series. Archeocytes exhibit cytological characteristics of unspecialized cells capable of high levels of synthetic activity while other cell types of C. carolinensis, for the most part, can be characterized as fully differentiated cells displaying more restricted synthetic capabilities but often accumulating neutral mucoproteins. The presence of aggregates of amebocytes, not identifiable as archeocytes and possibly engaged in gemmule formation, is discussed in terms of current concepts of gemmulation and cellular developmental capabilities in sponges.
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  • 26
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    Journal of Morphology 143 (1974), S. 1-1 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
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  • 27
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    Journal of Morphology 143 (1974), S. 337-347 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Scanning electron microscopy revealed spores of Nosema apis and Thelohania fibrata to be egg-shaped, but only the mature spore of T. fibrata was shown to possess a horseshoe-like concavity at the posterior pole. Freezeetched preparations indicated that this concavity was due to a thin area of the spore coat. Freeze-etching studies also show spores of N. apis do possess an umbrella-shaped polaroplast, and a polar filament which is arranged in a double layer with over 30 coils. The spore of T. fibrata contains a pear-shaped arrangement of the polaroplast membrane, and a polar filament arranged in a single layer of 22 coils.
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  • 28
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    Journal of Morphology 143 (1974) 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
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  • 29
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    Journal of Morphology 142 (1974), S. 351-363 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Gill development begins on the sixth day of incubation at 10°C and is complete by 31 days (hatching). Gill arches are formed by fusion and perforation of ectoderm and endoderm across the pharyngeal wall. A primary branchial artery forms within each arch and a second branchial artery forms as a branch from its ventral end. A series of filament loop vessels forms connecting the two arteries and when several are patent a unidirectional blood flow is established via afferent (second) branchial artery, filament loop vessels to efferent (primary) branchial artery. Part of the efferent branchial artery just above its junction with the afferent branchial artery constricts and occludes. It is suggested that this change in the pattern of blood flow is dependent on differences in resistance of the two branchial arteries. A later extension of the gill ventrally is thought not to be homologous with similar regions in elasmobranchs and Acipenser.
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  • 30
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
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    Notes: Scanning and transmission electron microscopy studies were conducted on the antennal sensory sensilla of the hymenopteran parasitoid, Cardiochiles nigriceps Viereck, of the family Braconidae. Distinct morphological differences were found between the chemoreceptors of the male and female. Curved, non-fluted, thin-walled sensilla were found to be very abundant on the male and restricted in location and number on the female. Trichoid, placoid and fluted basiconic sensilla were numerous on the antennal flagella of both sexes. Smooth basiconic sensilla were restricted in number to one per flagellar segment in both sexes. Behavioral data suggest that bent-tipped, thick-walled sensilla unique to the female are involved in detecting a chemical(s) emitted from the host, Heliothis virescens (Fab.).
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  • 31
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
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    Notes: Well preserved transitional cells were found between differentiated cells and horny cells of the frog epidermis, thus facilitating the study of the sequential events involved in horny cell formation. Autolysosomes appear to play an important role in the formation of horny cells. These structures preferentially digest those cytoplasmic components which are not necessary constituents of the terminal horny cell. The release of the contents of the small mucous granules into the intercellular spaces is one of the initial events in horny cell formation. Filaments and large mucous granules seem to be resistant to the lytic digestion and contribute to the bulk of the horny cell. Loss of fluids through the plasma membrane and consolidation of the remaining constituents, results in a flattened horny cell. The appearance of a thickened membrane around the horny cell signifies the completion of the transformation process.
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  • 32
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    Journal of Morphology 142 (1974) 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The fiber constituents and connections of the calyces  -  the input-receiving regions  -  of the corpora pedunculata (“mushroom bodies”) were studied in reduced silver preparations from the American cockroach, Periplaneta americana (L.). In the outer synaptic layer of the calyces five fiber classes were distinguished, the first three of which arise outside the mushroom body. (1) Four highly similar neurons with somata near the optic lobe branch into different parts of the ipsiateral protocerebrum, including both calyces. Their fibers are highly constant in arrangement and position and contain small nucleus-like bodies. (2) The tractus olfactorio-globularis (sensu lato) emits fiber groups which course along the calycal walls as “calycal tracts” before ultimately dissipating into the synaptic layer. Variability within these tracts is described. (3) Fibers of undertermined origin outside the mushroom body radiate from the calycal center outwards through the synaptic layer. (4) From the inner calycal layer of neurites belonging to intrinsic mushroom-body neurons, perpendicular collaterals enter the synaptic layer. (5) Intrinsic-neuron somata near the calycal rim emit fibers which course tangentially within the synaptic layer from calycal rim to center. These fibers form a special peripheral zone in the pedunculus.The predominant presumably afferent calycal fiber class is that derived from the tractus olfactorio-globularis. No evidence was found for tracts from optic lobe to calyces. On this basis, and in light of the experimental and comparative anatomical literature, it is suggested that the corpora pedunculata of P. americana and other pterygotes are fundamentally second-order antennal sensory processing centers.Conflicting observations in earlier reports are critically discussed.
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  • 35
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 203-205 
    ISSN: 1618-2650
    Keywords: Strukturaufklärung von Sesquiterpenalkoholen ; TAS-Verfahren, Mikrodehydrierung ; Chromatographie, Dünnschicht ; bicyclisch, mit Decalin-Grundgerüst
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Aus dem ätherischen Öl der Haselwurz wurden erstmalig die 4 Sesquiterpenalkohole α-Eudesmol, β-Eudesmol, Selinan-7,11-diol und Selin-6(7)en-11-ol isoliert und identifiziert. Dabei wurde zur Einengung der Strukturmöglichkeiten die dehydrierende TAS-Methode (Schwefel-Dehydrierung) eingesetzt. Sie lieferte bei ungesättigten C15-Alkoholen gute Ergebnisse. Gesättigte Sesquiterpenalkohole mit Decalin-Grundgerüst ließen sich besser nach der Selenmethode dehydrieren. Von den entstandenen Naphthalin-Derivaten wurden die UV-Spektren direkt von der DC-Platte aufgenommen und zur Identifizierung herangezogen. Durch diese Kombination der Mikroverfahren konnte das Grundgerüst der Alkohole mit Mikrogramm-Mengen eindeutig bestimmt werden.
    Notes: Abstract In the essential oil of Asarum europaeum L. the four sesquiterpene alcohols α-eudesmol, β-eudesmol, selinane-7,11-diol and seline-6(7)en-11-ol have been isolated and identified. For limiting the possibilities of structure the dehydrogenating TAS method (sulphur dehydrogenation) has been employed. Good results have been obtained with unsaturated C15-alcohols. Saturated sesquiterpene alcohols with decalin structure could be better dehydrogenated by the selenium method. UV spectra have been recorded of the naphthalene derivatives formed directly from the thin-layer plate and employed for identification. By this combination of micro methods the basic structure of the alcohols could be determined unequivocally with μg amounts.
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  • 36
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 337-342 
    ISSN: 1618-2650
    Keywords: Analyse der Metallchelate von o,o′-Dihydroxyazoverbindungen ; Chromatographie, Dünnschicht
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung In einer früheren Veröffentlichung [4] ist auf die Möglichkeit der chromatographischen Trennung strukturisomerer Metallchelate hingewiesen worden; sie soll hier ausführlicher dargestellt werden. Weiterhin wird die Trennung von 1:2-Mischkomplexen von Azofarbstoffen und von 1:2-Metallkomplex-Mischungen durch Dünnschicht-Chromatographie (DC) an Polyamid beschrieben. Unter bestimmten Voraussetzungen kann durch DC an Kieselgel zwischen 1:2-Metallkomplexfarbstoffen mit Sulfonsäureamid- bzw. Alkylsulfongruppen und solchen ohne diese Substituenten unterschieden werden. Die beschriebenen DC-Methoden ermöglichen bei richtiger Interpretation eine eindeutige Unterscheidung zwischen strukturisomeren Metallkomplexen der 1:1- und 1:2-Reihe, sowie Mischkomplexen und Komplexmischungen vom 1:2-Metall-chelattyp unsulfierter o,o′-Dihydroxyazoverbindungen. Symmetrische o,o′-Dihydroxyazoverbindungen, wie z.B. das 2,2′-Dihydroxy-5,5′-dimethyl-azobenzol(7), sind geeignete Komplexbildner für Schwermetallkationen, um diese als farbige Chelate mit Hilfe der DC voneinander zu trennen. Strukturisomere sind wegen der Molekülsymmetrie ausgeschlossen, so daß die Ergebnisse eindeutig sind.
    Notes: Abstract In an earlier publication [4] the possibility of the Chromatographic separation of structurally isomeric metal chelates was mentioned; this is dealt with here in more detail. Further the separation of 1:2 mixed complexes from azo dyes and 1:2 metal-complex mixtures by thin-layer chromatography (TLC) on polyamide is described. In certain circumstances it is possible to distinguish between 1:2 metal-complex dyes with sulphonamide or alkylsulphonyl groups and those without these substituents by TLC on silica gel. The TCL methods described allow-when correctly interpreted-an unambiguous distinction between structurally isomeric metal complexes of the 1:1 and 1:2 series, and mixed complexes and mixtures of complexes of the 1:2 metal-chelate type of unsulphonated o,o′-dihydroxyazo compounds. Symmetrical o,o′-dihydroxyazo compounds, such as 2,2′-dihydroxy-5,5′-dimethylazobenzene(7), are suitable as complex-formers for heavy-metal ions, allowing the separation of the latter as their coloured chelates with aid of TLC. Structural isomers are excluded because of the molecular symmetry, so that the results are unambiguous.
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  • 37
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 367-368 
    ISSN: 1618-2650
    Keywords: Best. von p-Phenetidin, p-Aminophenol, p-Amino-phenoxy-essigsäure ; Spektralphotometrie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 38
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    Fresenius' Zeitschrift für analytische Chemie 269 (1974), S. 15-18 
    ISSN: 1618-2650
    Keywords: Best. von Sulfit mit Trinitrobenzoesäure ; Spektralphotometrie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung SO3 2− kann mit Trinitrobenzoesäure innerhalb von 2 min photometrisch bestimmt werden. SO4 2−, S2O3 2−, S2− und SxO6 2− in Konzentrationen bis zu 1 mMol/100 ml stören nicht. Die untere Bestimmungsgrenze beträgt 0,22mg SO3 2−/100 ml, die Standardabweichung bei der Bestimmung von 7 mg SO3 2− ± 0,59 Rel.-%.
    Notes: Abstract SO3 2− can be determined photometrically with trinitrobenzoic acid within 2 min. SO4 2−, S2O3 2−, S2− and SxO6 2− in concentrations up to 1 mMole/100 ml do not interfere. The limit of determination is 0.22 mg SO3 2−/100 ml, the standard deviation for the determination of 7 mg SO3 2− is ± 0.59 Rel.-%.
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  • 39
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    Fresenius' Zeitschrift für analytische Chemie 269 (1974), S. 10-15 
    ISSN: 1618-2650
    Keywords: Chromatographie, Dünnschicht ; Vergleich von Zweistrahldensitometern
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Zur Eliminierung von Störungen der quantitativen Auswertung von Dünnschicht-Chromatogrammen durch Unregelmäßigkeiten der Sorptionsschicht werden öfters Zweistrahlgeräte verwendet. Diese Arbeit berichtet über die Simulation verschiedener Zweistrahlgeräte auf einem Einstrahlgerät mit Hilfe von Digitalrechnern, um auf diesem Wege eindeutige Aussagen über den Genauigkeitsgewinn treffen zu können. Die relativen genäherten Standardabweichungen aus einer größeren Anzahl von Messungen ergaben folgende Werte: Einstrahlgerät 3–5%, Zweistrahlgerät 2–4% und Zweiwellenlängengerät 2,5–4%.
    Notes: Abstract To avoid errors caused by irregularities of chromatoplates in quantitative TLC often double beam densitometers are used. This paper describes the simulation of different double beam instruments using a single beam scanner and digital computers, to obtain distinct data on the increase in accuracy. The relative standard deviations from a greater number of experiments are: single beam scanner 3–5%, double beam instrument 2–4% and dual wave-length scanner 2.5–4%.
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  • 40
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 31-31 
    ISSN: 1618-2650
    Keywords: Best. von Hydroxypropylgruppen in Cellulose-Mischäther ; Spektralphotometrie ; Ninhydrin als Reagens
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 41
    ISSN: 1618-2650
    Keywords: Best. von Toluidinen ; Chromatographie, Dünnschicht ; diazidodisulfostilbenimprägnierte Schichten
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 42
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 177-181 
    ISSN: 1618-2650
    Keywords: Untersuchung der Autoxidation von Fettsäureestern ; Chromatographie, Dünnschicht
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Mittels Dünnschicht-Chromatographie kann man den Ablauf von Autoxidationsprozessen an Lipiden qualitativ anhand der auftretenden Reaktionsprodukte verfolgen. In vorliegender Arbeit wurden verschiedene Laufmittel auf Silicagel hinsichtlich ihres Trennvermögens für Gruppen von Autoxidations-produkten erprobt. Ferner werden aufgrund umfangreicher Untersuchungen Sprühmittel zur Erkennung solcher Stoffgruppen auf dem Dünnschicht-Chromatogramm benannt. Am Beispiel der Autoxidation von c-9-Octadecensäuremethylester ohne und mit Zusatz von DDE wird die Leistungsfähigkeit der beschriebenen Arbeitsweise belegt.
    Notes: Abstract The autoxidation of lipids has been followed qualitatively by means of the reaction products. The separating ability of different solvents on silica gel for groups of autoxidation products has been tested. Furthermore, spraying agents for the detection of these groups on the chromatogram are given. The autoxidation of c-9-octadecenic methyl ester with and without addition of DDE serves as an example for the efficiency of the method.
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  • 43
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 208-208 
    ISSN: 1618-2650
    Keywords: Best. von Amylose ; Spektralphotometrie ; zwei Wellenlängen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 44
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 257-264 
    ISSN: 1618-2650
    Keywords: Schwefeldehydrierung, Selendehydrierung ; Ultramikrobereich, Apparatur, TAS-Verfahren. Thermofraktographie/TAS-Verfahren/Chromatographie, Dünnschicht ; Schwefel- und Selendehydrierung, Ultramikrobereich. Analyse von Sesquiterpenderivaten, Abietinsäure. Steroiden ; Chromatographie, Dünnschicht ; Schwefel- und Selendehydrierung, TAS-Verfahren
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird eine Schnellmethode beschrieben, die es erlaubt, unter kontrollierten Bedingungen mit 50–300 μg Ausgangsmaterial eine gekoppelte Dehydratisierung und Schwefel- bzw. Selendehydrierung durchzuführen. Hierbei wird die Probe mit einer Kaliumhydrogensulfat-Schwefel- bzw. Selenmischung für einige Minuten bei vorbestimmten Temperaturen zwischen 160–400° C im TAS-Ofen bzw. Tasomat erhitzt. Die entstehenden Aromaten werden durch einen Stickstoffstrom von 10 ml/min direkt auf den Startpunkt einer DC-Schicht transferiert. Anschließend wird chromatographiert und die auftretenden Reaktionsprodukte werden identifiziert. Zum Studium der Reaktionsvorgänge und der optimalen Temperaturbereiche dient die Thermofraktographie. Es sind Anwendungsbeispiele aus der Sesquiterpen-, Diterpen- und aus der Steroidreihe gegeben.
    Notes: Abstract A rapid method is described which permits to carry out a coupled dehydratization and sulphur resp. selenium dehydrogenation with 50–300 μg of starting material under controlled conditions. The sample is heated on a potassium hydrogen sulphate-sulphur resp. selenium mixture at preselected temperatures of between 160–400° C for several minutes in the TAS-oven resp. the Tasomat. The resulting aromatic components are transferred directly to the starting point of a TLC-plate by a stream of nitrogen at 10 ml/min and the reaction products are identified after chromatography. Thermofractography is applied to study the reaction processes and to determine the optical temperature ranges. Examples of application to the groups of sesquiterpenes, diterpenes and steroids are listed.
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  • 45
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 284-284 
    ISSN: 1618-2650
    Keywords: Best. von Aluminium ; Spektralphotometrie ; SPADNS
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 46
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 285-286 
    ISSN: 1618-2650
    Keywords: Nachw. von Canthaxanthin in Biolog. Material ; Chromatographie, Dünnschicht ; Fertigfolien UV 254
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 47
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 286-286 
    ISSN: 1618-2650
    Keywords: Best. von Kupfer, Nickel, Kobalt mit Benzoyltrifluoraceton ; Spektralphotometrie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 48
    ISSN: 1618-2650
    Keywords: Best. von Kresolen, Phenol, Xylenolen, Dimethylphenolen ; Chromatographie, Dünnschicht ; imprägn. Fertigfolien u. Kieselgel, Nachweisgrenzen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 337-340 
    ISSN: 1618-2650
    Keywords: Abtrenn. des 2,4-Dinitrophenylhydrazons von Formaldehyd, Acetaldehyd, Acrolein, Crotonaldehyd, Furfurol ; Chromatographie, Dünnschicht
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird ein dünnschicht-chromatographisches Verfahren zur Trennung von Formaldehyd, Acetaldehyd, Furfurol, Acrolein und Crotonaldehyd in Form der 2,4-Dinitrophenylhydrazone beschrieben. Die Derivate werden aus Pyridin, Tetrahydrofuran oder Dioxan aufgetragen und innerhalb von 6 h nach der Durchlauftechnik an Kieselgel F 254-Rapidplatten mit Tetrachlorkohlenstoff/Pyridin (90∶10) aufsteigend entwickelt. Die Laufstrecken verhalten sich wie 1∶1,3∶1,7∶2,1∶2,3.
    Notes: Abstract The derivatives are applied on rapid plates silica gel F 254 from pyridine, tetrahydrofuran or dioxan solution and separated during 6 h by ascending overrun development using carbon tetrachloride/pyridine (90∶10) as a solvent. The distances travelled from the starting point are in the ratio 1∶1.3∶1.7∶2.1∶2.3.
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 359-361 
    ISSN: 1618-2650
    Keywords: Best. von Nitrat mitβ-Methylumbelliferon ; Spektralphotometrie ; hochselektive Modifikation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Anwendbarkeit der spektralphotometrischen Nitratbestimmung mitβ-Methylumbelliferon wurde durch folgende Maßnahmen wesentlich erweitert: Abtrennung auftretender Niederschläge mit einem Membranfilter aus Cellulosenitrat, Fällung bzw. Maskierung störender Anionen mit AgClO4 und Reduktion störender Kationen mit Na2SO3. Der Einfluß von mehr als 60 Kationen und 20 Anionen auf die NO3 −-Bestimmung wird angegeben.
    Notes: Abstract The applicability of the spectrophotometric nitrate determination by utilizingβ-methylumbelliferone has been extended by the following measures: Separation of eventual precipitates by means of a membrane filter consisting of cellulose nitrate, separating or masking of interfering anions with AgClO4 and reduction of interfering cations by the use of Na2SO3. The influence of more than 60 cations and 20 anions on the determination of nitrate is listed.
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 365-366 
    ISSN: 1618-2650
    Keywords: Turigeran, Multivitaminpräparate ; Chromatographie, Dünnschicht ; Fertigfolien
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 367-368 
    ISSN: 1618-2650
    Keywords: Uran(VI) ; Chromatographie, Dünnschicht ; DEAE-Cellulose, Phosphorsäure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 272 (1974), S. 37-39 
    ISSN: 1618-2650
    Keywords: Best. von Steroidsulfaten ; Spektralphotometrie ; Cu-Pyridin-Komplex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary A new procedure has been developed for the quantitative determination of steroid sulphates. The basic principle of the method is that a pyridine solution of the pyridinium salt of the steroid sulphate is shaken at room temperature with metallic copper powder or copper(I)-oxide, and the intensity of the coloured complex formed is measured at 310–350 nm. The method is suitable both for the total steroid sulphate determination of various extracts, and for the quantitative determination of steroid sulphates previously separated by some other method. Errors are in the range of 0.5–2%.
    Notes: Zusammenfassung Eine Lösung des Pyridiniumsalzes des Steroidsulfats in Pyridin wird bei Raumtemperatur mit metallischem Kupferpulver oder Kupfer(I)-oxid geschüttelt und die Absorption des gebildeten Farbkomplexes bei 310–350 nm gemessen. Das Verfahren eignet sich zur Bestimmung des Gesamtgehaltes an Steroidsulfat in verschiedenartigen Extrakten sowie zur Bestimmung von zuvor abgetrenntem Steroidsulfat. Die Fehler liegen im Bereich von 0,5–2%.
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    Fresenius' Zeitschrift für analytische Chemie 272 (1974), S. 44-44 
    ISSN: 1618-2650
    Keywords: Best. von Silber mit 4-(2-Pyridylazo)-resorcin ; Spektralphotometrie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 272 (1974), S. 48-48 
    ISSN: 1618-2650
    Keywords: Best. von Kobalt mit 1-Naphthamidoxim ; Spektralphotometrie ; Spuren
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 56
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    Fresenius' Zeitschrift für analytische Chemie 272 (1974), S. 206-206 
    ISSN: 1618-2650
    Keywords: Nachw. von Diphenyl ; Chromatographie, Dünnschicht ; verschiedene Reagentien u. Schichten
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 57
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    Fresenius' Zeitschrift für analytische Chemie 272 (1974), S. 283-283 
    ISSN: 1618-2650
    Keywords: Best. von Eisen(II) mit Thiodibenzoylmethan ; Spektralphotometrie ; Extraktion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 272 (1974), S. 284-285 
    ISSN: 1618-2650
    Keywords: Bestimmung von Glykolaldehyd in Äthylenglykol ; Spektralphotometrie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 272 (1974), S. 286-286 
    ISSN: 1618-2650
    Keywords: Nachweis von Herbiciden, Pesticiden ; Chromatographie, Dünnschicht ; Fertigfolien, Nachweisgrenzen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 272 (1974), S. 364-364 
    ISSN: 1618-2650
    Keywords: Best. von Cer(IV) mit Kristallviolett ; Spektralphotometrie
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    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 272 (1974), S. 366-366 
    ISSN: 1618-2650
    Keywords: Best. von Palladium mit Chromotrop 2R ; Spektralphotometrie
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    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 272 (1974), S. 368-368 
    ISSN: 1618-2650
    Keywords: Best. von DDT in Eiern ; Chromatographie, Dünnschicht
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 31-32 
    ISSN: 1618-2650
    Keywords: Best. von Iridium mit Acenaphthenchinonmonoxim ; Spektralphotometrie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 128-128 
    ISSN: 1618-2650
    Keywords: Nachw. von Alkoholen als Co-Xanthate ; Chromatographie, Dünnschicht
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 272-274 
    ISSN: 1618-2650
    Keywords: Best. von Gramicidin ; Chromatographie, Dünnschicht ; CAMAG Eluchrom
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Eine quantitative Methode zur Bestimmung von Gramicidin in Fermentationsproben, Extraktionslösungen und Tyrothricin- bzw. Gramicidin-Fertigprodukten wird beschrieben. Nach der dünnschicht-chromatographischen Trennung des Gramicidins von den Begleitstoffen erfolgt eine quantitative Elution des Fleckes mit dem CAMAC Eluchrom, die so gewonnenen Lösungen werden spektralphotometrisch ausgewertet.
    Notes: Abstract A quantitative method is described for the determination of gramicidine in fermentation broths, extracts and finished products of tyrothricine and gramicidine, respectively. After TLC-separation of gramicidine from accompanying substances a quantitative elution of the gramicidine spot is performed with the CAMAG Eluchrom. The solutions obtained are measured spectrophotometrically.
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 268-272 
    ISSN: 1618-2650
    Keywords: Chromatographie, Dünnschicht ; Peakerkennung u. Auswertung mit Digitalrechnern
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Arbeit beschreibt den prinzipiellen Aufbau eines Programms für Digitalrechner zur numerischen Peakerkennung und numerischen Integration von Remissionsgrad-Ortskurven bei der quantitativen DC. Durch integrierende Analog-Digitalwandlung und digitales Glätten wird das Signal/Rausch-Verhältnis verbessert. Die Peakerkennung erfolgt mit Hilfe der über eine Ausgleichsparabel numerisch differenzierten Meßkurve. Die Basislinienkorrektur bei nicht aufgelösten Peaks beruht auf einem Vergleich der Tangenten zwischen den Peakminima.
    Notes: Abstract The paper describes the principles of a programm for numerical peak detection and numerical integration for area determination by digital computers with respect to thin-layer chromatography. Integrating analog to digital conversion and digital smoothing will improve the signal to noise ratio. The first derivative will be found by smoothed numerical differentiation and is used for peak detection. The actual base line is corrected by eomparision of the tangents between the minima of the peaks.
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    Fresenius' Zeitschrift für analytische Chemie 269 (1974), S. 97-99 
    ISSN: 1618-2650
    Keywords: Best. der Zusammensetzung von Metallkomplexen ; Spektralphotometrie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary If the method of continuous variations as well as methods like the molar-ratio method are applied to complex formation reactions that take place stepwise, plots can be obtained in which the existence of intermediate complexes is fully obscured. An illustration is given for the complex formation between Cu2+ and pyridine-2,6-dicarboxylic acid.
    Notes: Zusammenfassung Über den Gebrauch spektralphotometrischer Methoden zur Bestimmung der Zusammensetzung von Metallkomplexen. Wenn die Methode der kontinuierlichen Variationen und Verfahren wie die Molar-ratio-Methode für den Fall stufenweiser Komplexbildung angewendet werden, können graphische Darstellungen erhalten werden, in denen die Existenz von intermediären Komplexen völlig verdeckt ist. Dies wird für die Komplexbildung zwischen Kupfer(II) und Pyridin-2,6-dicarbonsäure gezeigt.
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    Fresenius' Zeitschrift für analytische Chemie 269 (1974), S. 182-187 
    ISSN: 1618-2650
    Keywords: Best. von Aminosäuren mit p-Benzochinon ; Spektralphotometrie ; Charge-Transfer-Komplexe
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Aminosäuren können in Gegenwart organischer Lösungsmittel als Elektronen-Donator-Acceptor-Komplexe mit p-Benzochinon bestimmt werden. Die Methode vereinigt stabile Farbreaktion, hohe Empfindlichkeit (ɛ 490=2,5 cm2/μMol α-Aminosäure, 4,4 cm2/μMol α,ɛ-Aminosäure und ɛ 525=4,65 cm2/μMol Prolin), rasche, einfache und billige Durchführung mit guter Reproduzierbarkeit, ausreichender Spezifität und Unempfindlichkeit gegenüber Ammoniak und anorganischen Verbindungen. Es werden optimale Bedingungen für die Bestimmung von Aminostickstoff im Serum und Urin und Normalwerte bei Gesunden beschrieben.
    Notes: Abstract Amino acids can be determined as charge-transfer complexes by reaction with p-benzoquinone in the presence of organic solvents. This method combines high sensitivity (ɛ 490=2.5 cm2/μmole α-amino acid and 4.4 cm2 /μmole α,ɛ-amino acid; ɛ 525=4.65 cm2/μmole proline) and rapid, cheap and simple procedure with good reproducibility, sufficient specifity, stable colour and insensitivity to ammonia and inorganic compounds. Optimal conditions and normal values are reported for the determination of amino nitrogen in serum and urine.
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    Fresenius' Zeitschrift für analytische Chemie 269 (1974), S. 206-208 
    ISSN: 1618-2650
    Keywords: Best. von Dimethylsulfat in Luft ; Chromatographie, Dünnschicht ; Umsetzung zu Nitroanisol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird eine Methode beschrieben, die es gestattet, Dimethylsulfat (DMS) im Bereich der maximalen Arbeitsplatzkonzentration von 0,05 mg/m3 entsprechend 0,01 ppm zu bestimmen. Zunächst wird DMS zur Anreicherung an Kieselgel adsorbiert. Nach Desorption mit Aceton wird DMS mit 4-Nitrophenol-Na zu 4-Nitroanisol umgesetzt und dünnschicht-chromatographisch durch Intensitätsvergleich mit Standards bestimmt. Zur Erfassung des MAK-Wertes sind mindestens 500 l Probevolumen nötig. Bei einer Sauggeschwindigkeit von 3–4 l/min dauert daher eine Probenahme 2–2,5 Std. Über diesen Zeitraum sollten bei einer Raumluftuntersuchung möglichst ähnliche Konzentrationsverhältnisse vorliegen.
    Notes: Abstract A method is reported which allows the determination of dimethyl sulphate (DMS) in the range of the threshold limit of 0.05 mg/m3 resp. 0.01 ppm. At first DMS is concentrated by adsorption on silica gel. After extraction with acetone and reaction with 4-nitrophenol sodium salt to 4-nitroanisol the DMS is determined by thin-layer chromatography. Evaluation by comparison of intensity with standard spots. For the determination of the threshold limit at least 500 l of sample volume are needed. With an air sampling rate of 3 to 4 l/min the duration of sampling is 2 to 2.5 h. During this time the concentration of the examined air should not vary too much.
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 19-23 
    ISSN: 1618-2650
    Keywords: Best. von Phthalsäure ; Chromatographie, Dünnschicht ; Remissionsmessung, Kopplung mit Tischrechner
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Am Beispiel der Bestimmung von Phthalsäure wird die on line-Kopplung eines programmierbaren elektronischen Tischrechners über einen Integrator zur automatischen quantitativen Auswertung von Dünnschicht-Chromatogrammen durch Messung der Remission beschrieben. Das Verfahren arbeitet mit Mittelwertbildung der Integratorwerte der Scans in und gegen die Fließrichtung, um Basislinienfehler zu eliminieren. Der Rechner ermittelt aus den Vergleichsflecken über die Methode der kleinsten Summe der Fehlerquadrate die Eichgerade und berechnet hierüber die Substanzmenge in den Analysenflecken. Für die Auswertung wird eine quadratische Abhängigkeit der Fläche unter der Remissionsgrad-Ortskurve von der Substanzkonzentration angenommen. Die erreichte Genauigkeit lag bei etwa 2–2,5% (genäherte relative Standardabweichung).
    Notes: Abstract The paper describes the coupling of TLC-photometer, electronic integrator and desk calculator for the determination of phthalic acid by measurement of the remission at 280.3 nm. The average of integrator counts by scanning in and against development of the plate avoids errors caused by base line-drifts. From standards on the plate results a straight line by least squares using the quadratic proportionality of peak area to concentration. From this straight line the concentrations will be determined. The error of this method is in the range of 2–2.5% (relative standard deviation).
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 16-19 
    ISSN: 1618-2650
    Keywords: Best. von Organ. Säuren ; Chromatographie, Dünnschicht ; aliphatisch, aromatisch, Reisstärkeschichten
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary Aliphatic monocarboxylic, dicarboxylic, hydroxy, keto and amino acids were separated on rice starch thin layers with the solvent system: ethanol/water/ammonia (78∶20∶13). Different aromatic acids were separated on the same support with the solvent system: ethanol/n-butanol/water/ammonia (40∶30∶15∶15). Rf- and RM-values were determined and the validity of Martin's theoretical postulates on the relationship between chemical structure and Rf-values in partition chromatography was displayed. Calculation of group and basic constants was also carried out.
    Notes: Zusammenfassung Aliphatische Monocarbon-, Dicarbon-, Hydroxy-, Keto und Aminosäuren wurden dünnschicht-chromatographisch auf Reisstärke getrennt (Fließmittel: Äthanol/ Wasser/Ammoniak [78∶20∶13]). Verschiedene aromatische Säuren wurden auf der gleichen Schicht mit dem Fließmittel Äthanol/n-Butanol/Wasser/Ammoniak (40∶30∶15∶15) getrennt. Rf- und RM-Werte wurden bestimmt. Aufgrund der theoretischen Aufstellungen von Martin für die Beziehung zwischen Rf-Werten in der Verteilungs- chromatographie und chemischen Strukturen wurden Gruppen- und Grundkonstanten bestimmt.
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 32-32 
    ISSN: 1618-2650
    Keywords: Best. von Eisen(II) mit 7-Nitroso-8-hydroxychinolin-5-sulfonsäure ; Spektralphotometrie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 100-104 
    ISSN: 1618-2650
    Keywords: Analyse von binären Lösungsmittelgemischen ; Spektralphotometrie ; Solvatochrome Farbstoffe, synergistische Polaritätseffekte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary Empirical parameters of solvent polarity E T of some pure solvents and their binary mixtures (especially with CCl4 and CHCl3) were determined spectrophotometrically using solvatochromic pyridinium-N-phendl betaine dyes. Calibration curves are given for 16 binary solvent mixtures. The obtained E T values show that a synergetic polarity effect appears with the organic solvents containing C=O, P=O, and S=O groups in the mixture with chloroform. With these binary mixtures the increase of E T values results from the formation of 1∶1 complexes X=O... H-CCl3 by means of hydrogen bonding. Increasing number of methylene groups in the chain increases the synergism with these type of complexes.
    Notes: Zusammenfassung Empirische Parameter der Lösungsmittelpolarität E T einiger reiner Lösungsmittel und ihrer binären Mischungen (insbesondere mit CCl4 und CHCl3) wurden mit Hilfe von solvatochromen Pyridinium-N-phenolbetain-Farbstoffen bestimmt. Für 16 binäre Lösungsmittelgemische wurden Eichkurven ermittelt. Die erhaltenen E T -Werte zeigen, daß organische Lösungsmittel mit C=O-, P=O- und S=O-Gruppen in Mischungen mit Chloroform einen synergistischen Polaritätseffekt aufweisen. Die Zunahme der E T -Werte in diesen binären Mischungen beruht auf der Bildung von durch Wasserstoff brücken gebundenen 1∶1-Komplexen X=O... H-CCl3. Die Verlängerung der Alkylkette führt zu einer Zunahme des Synergismus bei dieser Art von Komplexen.
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 128-128 
    ISSN: 1618-2650
    Keywords: Trenn. von Pseudohalogeniden ; Chromatographie, Dünnschicht ; Fertigfolien, Nachweisgrenzen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 206-207 
    ISSN: 1618-2650
    Keywords: Best. von Chrom(III) mit ÄDTA ; Spektralphotometrie ; Differenzmethode im UV-Bereich
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 278-282 
    ISSN: 1618-2650
    Keywords: Best. von Fluor in Biolog. Material ; Spektralphotometrie ; Applikation von Flufenaminsäure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Nach Extraktion aller F-haltigen Substanzen (intakte Substanz plus Summe aller Metaboliten) aus Urin (alkalisch in der Wärme hydrolysiert) von Menschen und Tieren, welche Flufenaminsäure bzw. deren Derivate appliziert bekamen, können Untersuchungen der Ausscheidungsbilanz durchgeführt werden. Nach alkalisch oxidativem Abbau (Wurzschmittsche Bombe) wurde aus schwefelsauren Ansätzen mit SiO2 destilliert und die Ansätze mit Alizarin-3-methylamin-N,N-diessigsäure-Cer(III)-Komplex bei pH 4,35 colorimetrisch untersucht. Messungen im Konzentrationsbereich ≤1 μg pro Meßansatz sind möglich. Die Ergebnisse der renalen Elimination von Flufenaminsäure und Metaboliten beim Menschen (49,4±4,6%; N=10) stimmen größenordnungsmäßig mit den Befunden anderer Autoren, welche Tracer-Methoden angewendet hatten (51%; N=4), gut überein und beweisen damit die Brauchbarkeit der Methode.
    Notes: Abstract After extraction of all F-containing substances (intact substance and the sum of all metabolites) from urine (hydrolysed in alkali under heating) of both man and animals after administration of flufenamic acid and derivatives, the balance of excretion can be determined. After alkaline oxydative degradation (Wurzschmitt bomb) of these extracts and distillation in the presence of sulphuric acid and SiO2 the distillates were investigated colorimetrically at pH 4.35 after addition of an alizarine-3-methylamino-N,N-diacetic-cerium(III) complex. Measurements in the range of ≤1 μg per sample used are possible. The results obtained for the renal elimination of flufenamic acid and metabolites in man (49.4±4.6%; N=10) are in concordance with the results of other authors who used tracer methods (51%; N=4) and prove the practicability of this method.
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 282-285 
    ISSN: 1618-2650
    Keywords: Best. von Dihydrocodein neben Noscapin ; Spektralphotometrie ; Anwendung von Orthogonalfunktionen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die direkte photometrische Bestimmung von Dihydrocodeinbitartrat (5 mg) neben der Hauptkomponente Noscapin (Narcotin)-hydrochlorid (25 mg) ohne Abtrennung gelingt, wenn zur Auswertung Orthogonalpolynome herangezogen werden. Eine andere Methode basiert auf der Fällung der Noscapinbase mit gesättigter Natriumacetatlösung. Auch in diesem Fall wird das Dihydrocodein über Orthogonalfunktionen bestimmt, um den Restanteil von Noscapin zu eliminieren und eventuell störende unspezifische Untergrundabsorptionen auszuschließen. Die Standardabweichung beträgt 1,56 ohne Abtrennung und 0,66 bei Fällung des Noscapins.
    Notes: Summary The orthogonal function method is applied to the determination of dihydrocodeine bitartrate as a minor component (5 mg) in presence of noscapine hydrochloride (25 mg) without separation. Another method based upon precipitating noscapine by a saturated solution of sodium acetate is also presented. Dihydrocodeine is determined in the filtrate using the orthogonal function method to correct for the unprecipitated fraction of noscapine. Standard deviation is 1.56 and 0.66 for direct and precipitation methods, respectively.
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  • 78
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 356-359 
    ISSN: 1618-2650
    Keywords: Nachw. von Pesticiden ; Chromatographie, Dünnschicht ; Nitroverbindungen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird eine Analysenmethode zum Nachweis und zur Trennung von 16 Nitro-Pesticiden beschrieben. Nach einer dünnschicht-chromatographischen Trennung werden die Nitroverbindungen in primäre aromatische Amine übergeführt, die durch Diazotierung und Kupplung mit Bratton-Marshall Reagens nachgewiesen werden. Die photometrische Messung des eluierten Azofarbstoffes gestattet eine quantitative Bestimmung.
    Notes: Abstract An analysis method for the detection and separation of sixteen nitro-pesticides is described. After thin-layer chromatographical separation, the nitro-compounds are converted to primary aromatic amines which are detected by diazotization and subsequent coupling with Bratton-Marshall reagent. The photometric measuring of the azo-dye, obtained by elution, permits quantitative determination.
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  • 79
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 366-367 
    ISSN: 1618-2650
    Keywords: Nachw. von δ-Aminolävulinsäure-Dehydratase-Inhibitoren ; Chromatographie, Dünnschicht
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 80
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 367-368 
    ISSN: 1618-2650
    Keywords: Nachw. von Peroxidase-Inhibitoren ; Chromatographie, Dünnschicht
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 81
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    The @Anatomical Record 178 (1974) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 82
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The urinary bladder of the bullfrog, Rana catesbiana has been studied by light and electron microscopy. Three epithelial cell types were found: (1) granular cells, (2) mitochondria-rich cells, and (3) basal cells. The structure of the Rana catesbiana bladder differs from that of the toad Bufo marinus, in several respects: it lacks a mucous (goblet) cell type, its granular cells do not contact the underlying basement membrane, it has specialized, smooth-muscle cell-basal epithelial cell contacts, not previously described in amphibian bladders, and its mucosa is richly innervated. Mitochondria-rich cells within the bullfrog bladder epithelium were occasionally observed touching the basement membrane. The specialized smooth muscle-basal cell contacts provide anatomical evidence for how regulatory vasoactive substances such as neurohypophyseal peptides might alter epithelial geometry. Many nerve endings invest the mucosa just beneath the epithelial basement membrane in proximity to mitochondriarich cells and basal cells. The possible role of neural regulation in epithelial transport was discussed.
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  • 83
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Postnatal maturation of nonmyelinated fiber bundles (Schwann bundles) was studied in the sciatic nerves of Snell's dwarf mice. The homozygous recessive of this strain has been previously shown to be characterized by multiple pituitary hormone deficiencies and secondary hypothyroidism.In the normal littermates a reduction occurred between 10 and 14 days in the number of fibers per fascicle, or subdivision, of each Schwann bundle, and by 26 days nearly all of the axons were separately embedded in cytoplasmic furrows of their associated Schwann cells. Only a few large fascicles were seen in normal sciatic nerve specimens at 26 and 50-53 days. In contrast, fiber bundle fascicles in the mutant nerves were still represented, even at 50-53 days, by numerous tightly-packed axons, as seen in the immature nerves at 10-12 days post-partum.On the basis of the dwarf's physiological background, these results suggest an involvement of the endocrine system during later stages of peripheral nerve maturation. The possible mechanisms affected by postnatal endocrine deficiency and thereby leading to delayed segregation of nonmyelinated fibers within Schwann bundles are discussed.
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  • 84
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    The @Anatomical Record 178 (1974), S. 139-143 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Hamsters injected at 0900 on day 1 of the cycle (metestrus) with either 0, 5 or 15 IU pregnant mare's serum (PMS) were killed at 1500 of days 1 to 4 of the cycle and the ovaries prepared for light microscopy and for a quantitative evaluation of follicular development. In the untreated cyclic hamster, the maximal number of preantral follicles with eight or more layers of granulosa cells occurred between the afternoon of day 4 (proestrus) and day 1, coinciding with the highest blood levels of FSH and LH. It is concluded that the elevated preovulatory levels of gonadotropins not only induce the ovulation of the mature antral follicles but at the same time recruit the next set of follicles for development during the new cycle.By the afternoon of day 1, treatment with either 5 or 15 IU PMS recruited more follicles into large preantral and incipient antral stages than in the untreated hamsters. However, by day 2 the pattern of follicular distribution was similar between the 5 IU PMS and untreated group whereas considerably more antral follicles had differentiated in the animals given 15 IU PMS. The ability of 15 IU PMS to elicit superovulation therefore depends on the levels being initially high enough to mature more follicles at critical stages of their development; the prolonged biological half life of PMS then sustains these follicles throughout the cycle.
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  • 85
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    The @Anatomical Record 178 (1974), S. 203-209 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: During the postnatal development of the submandibular gland, the stimulation of DNA synthesis and mitosis by a single injection of isoproterenol, measured as the percentage of labeled cells in radioautographs, was dependent on the age of the rat. The drug had no effect on the proliferative activity in two day old rats, but stimulated DNA synthesis in older (7-42 day old) animals. In general, the degree of stimulation was directly related to the proportion of acinar cells and inversely related to the proliferative activity in the gland of control rats. An analysis of various cell types revealed that the stimulation of DNA synthesis in the gland was essentially restricted to the acinar cells in rats older than 14 days of age. In seven day old rats, the acinar cells were not stimulated, but their precursors, the proacinar cells, the terminal tubule cells and the intercalated duct cells were stimulated to synthesize DNA by isoproterenol. This suggested that isoproterenol had an effect on the transformation of precursor cells to acinar cells.
    Additional Material: 2 Ill.
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  • 86
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Keratinization or mucification of the epithelium of the rat vagina is related to the hormonal state of the animal. During the normal cycle and after the administration of exogenous hormones (estrogen and progestin) to spayed animals, the surface characteristics and topography of the vaginal epithelium were studied with the scanning electron microscope. During estrus and under the influence of estrogen, the superficial cells were keratinized, overlap each other like shingles, and are continuously sloughed off. Like the surface of other keratinizing epithelia, theirs has a characteristic microridge pattern. In ovariectomized animals, the apical surface is covered with microvilli instead of microridges, and the cells resemble hexagonally shaped units, tightly bound instead of overlapping each other. At the boundary between the cells, a ridge demarcates the cells. The surface configurations of progestin-treated, progestin plus estrogen-treated, and diestrous animals are the same as in spayed animals.
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  • 87
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    The @Anatomical Record 178 (1974), S. 1-1 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 88
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    The @Anatomical Record 178 (1974), S. 41-48 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: This report compares the arterial supply of the lumbo-sacral spinal cord in the monkey with that of man. The arterial supply to the lumbo-sacral cord of 100 monkeys (82 Rhesus and 18 Mangabey) was demonstrated by perfusion techniques. We tabulated the level and side of origin of the great anterior medullary artery. Previous authors have shown that in man the peak incidence of the great anterior medullary artery is at T-10. The peak incidence in the monkey is at L-1. There are other features of the arterial supply to the lumbo-sacral cord of the monkey that are different from man.
    Additional Material: 6 Ill.
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  • 89
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: An initial study of the effects of long-term ovariectomy on fimbrial and ampullar epithelia from rabbit oviducts has been made with the scanning electron microscope. Several of the rabbits were given estradiol benzoate before they were killed. These observations were compared with those of epithelial cells from similar oviductal segments from post-ovulatory rabbits that served as controls.Fimbriae from oviducts of control animals were densely ciliated, partially concealing the bulbous processes of the secretory cells. In the ampullae the processes of the secretory cells were the predominant structure, their bulbous apices rising frequently above the tips of the cilia.When rabbits had been spayed for 16-18 months, the epithelial cells of both fimbriae and ampullae showed a remarkable change. A few cilia in small clumps were scattered among the secretory cells. The free surface of the secretory cells had become flattened and hexagonal in shape. Their microvilli were short, and from the center of each cell a thick, stubby central cilium protruded.Estrogen given the long-term spayed rabbits caused almost complete reciliation as well as restoration of the bulbous processes of the secretory cells.
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  • 90
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    The @Anatomical Record 178 (1974), S. 127-137 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The morphogenesis of cerebellum has been studied in 6-19 day old chick embryos after a single injection of 0.05 mg of cyclophosphamide into the yolk sacs on the fifth day of incubation. Besides degeneration of Purkinje cells, rate of development was markedly retarded as evidenced by late appearance of the fissures and folia of the cerebellum. Purkinje cells remained disorganised up to 18 days of incubation, though in controls they were arranged in a single line by the fifteenth day. The thickness of the external granular layer increased and persisted for a longer period in the treated embryos. The cytoarchitecture returned to normal on nineteenth day of incubation, but the size of the cerebellum was significantly smaller than that of controls (P 〈 0.001). Such transient disorganisation of the morphogenetic events in the neural tube may lead to inadequate and defective induction of surrounding mesenchyme, thereby resulting in defective skull formation through which the brain can herniate, i.e., exencephaly as reported in our earlier studies after cyclophosphamide administration in chicks (Singh et al., '71; Singh and Gupta, '72) and rats (Singh et al., '72).
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  • 91
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    The @Anatomical Record 178 (1974), S. 187-201 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The postnatal differentiation of acini in the submandibular glands of 2-42 day old rats given 3H-thymidine was studied by using radioautographs prepared from Epon-embedded, PAS and iron hematoxylin stained sections. The changes in morphology, population size and proliferative activity of various cell types in the gland were analyzed. At two days of age, rudimentary secretory units, designated as terminal tubules, were located at the end of the duct system and consisted of three cell types: (1) terminal tubule cells (30.7%) with darkly-stained granules, (2) proacinar cells (23.6%) with large, lightly-stained granules, and (3) acinar cells (1.6%) with PAS-positive granules. The proacinar cells, which underwent mitosis, disappeared within the first two weeks of life. The terminal tubule cells increased in number between 2 and 14 days of age, but became less numerous thereafter and disappeared by six weeks. Concomitantly, the number of acinar cells increased linearly with age and at a much greater rate than that of intercalated duct cells. Yet the rate of proliferation of acinar cells was comparable to that of intercalated duct cells. The overall proliferative activity in the gland decreased with age, and was inversely correlated with the relative frequency of acinar cells in the gland. On the basis of above data, it is postulated that, during the formation of acini from terminal tubules, acinar cells have a dual origin: they arise from proacinar cells during the first one to two weeks and from terminal tubule cells between two and six weeks of age.
    Additional Material: 6 Ill.
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  • 92
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    The @Anatomical Record 178 (1974), S. 623-630 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: It has often been reported that facial proportions remain constant throughout the fetal period. Such conclusions, however, have been based largely on the erroneous assumption that two dimensions are growing isometrically if one bears a statistically significant linear relation to the the other. In order to test the hypothesis that proportion is independent of time, sagittal histologic sections from 32 human fetuses (12-25 weeks) were analyzed cephalometrically. The linear regression on head length (HL) and the associated coefficient of correlation were calculated for each of a variety of craniofacial measures. In addition, all linear dimensions were transformed so that the size of the anterior cranial base was held constant throughout the series. It was assumed that if shape be constant, all Y-intercepts should be zero, and angular and transformed linear dimensions should show no statistically significant linear correlation with HL. These three criteria were met uniformly by facial and anterior cranial base dimensions, but not by measurements which involved the posterior cranial base. It is concluded, therefore, that in the sagittal plane the second trimester mandible, midface, and anterior cranial base grow isometrically, while the posterior cranial base becomes relatively smaller.
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  • 93
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    The @Anatomical Record 178 (1974) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 94
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Light microscopy of semithin sections revealed an increase in blood vessel profiles between one and three weeks postnatal. Ultrastructurally, at birth, there were few patent vessels, but endothelial cells enclosing a slit-like lumen were numerous. The endothelial cells contained a high concentration of free ribosomes and pinocytotic vesicles. Pseudopod projections of the endothelial cells into the vascular lumen were often present. The nuclei were very irregular and dense with clumped chromatin. The basal lamina varied in thickness. During the period between one and three weeks the nuclei of endothelial cells became less dense; the lumen became patent and the endothelial wall progressively thinner. The periphery of the vessel became completely surrounded by glial end feet and the basal lamina was regular and prominent. By three weeks, most blood vessels resembled blood vessels observed in a mature animal. Pericytes were present at all stages of development. The extracellular space which was quite conspicuous at birth was greatly reduced by the third week.
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  • 95
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Light microscopic studies using a battery of basic dye stains combined with sialidase and hyaluronidase digestions indicated that the extensive basophilia of the maternal surface of the placental syncytium largely results from the presence of a non-sulfated mucosubstance specifically identified as hyaluronic acid. Ultrastructural examination of dialyzed iron (DI) stained specimens revealed that DI-positive filaments observed along the syncytial surface were removed by hyaluronidase digestion. Staining with the lectins, Concanavalin A or lentil bean hemagglutinin produced an intense and periodic pattern of staining that was not enzyme labile. Incubation of tissue sections in the enzyme solutions or control buffers allowed the lectins to penetrate the syncytial plasma membrane and stain material within the endoplasmic reticulum presumed to be human chorionic gonadotropin. The maternal surface exhibited essentially no reactivity for acid phosphatase but showed strong alkaline phosphatase activity with a periodic staining pattern. With each of the techniques used there was variability in the intensity of staining in different regions along the maternal surface, suggesting that functionally different zones may be identified cytochemically. Only minor differences were observed in the cytochemical reactivity of early compared with term placenta.
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  • 96
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Evidence for a direct neural projection from the retina to the hypothalamus in the golden hamster (Mesocricetus auratus) is presented. In 25 blinded animals degeneration was followed in sections prepared according to the Wiitanen ('69) silver impregnation method. Degenerative axons were found in the optic tract, chiasm, and nerve, terminating in the lateral geniculate body and superior colliculus. A large collateral bundle of degenerating axons was observed curving medially and dorsally to enter the hypothalamus at the level of the mamillary body. This bundle turned diffusely rostrally and terminated on neurons in the ventromedial nucleus of the hypothalamus.It is proposed that two alternate pathways exist for the effect of photoperiodicity on the reproductive cycle in the hamster, one involving the pineal gland directly and the hypothalamus indirectly, and the other a direct retino-hypothalamic projection.
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  • 97
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    The @Anatomical Record 179 (1974) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 98
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    The @Anatomical Record 179 (1974), S. 147-161 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The organization of the sensory innervation of Golgi tendon organs (GTO) from E. carpi ulnaris of the cat is described. The large Ib afferent fiber gives rise to small myelinated branches which become oriented longitudinally in a neural compartment of the GTO capsule lumen. The latter give rise to smaller, unmyelinated branches which further arborize among loosely packed collagen bundles. The unmyelinated fibers form numerous varicosities and small terminal branches which have portions of the axolemma covered only by basal lamina which intervenes between the collagen bundles and the axolemma. In places, the axon's surface may lack all investments and nerve and collagen come into intimate association. The large unmyelinated branches and their varicosities have different axoplasmic characteristics compared with the small unmyelinated terminal portions. The latter contain few or no mitochondria, vesicles, neurotubules, and neurofilaments. In addition to the description of the terminals, the similarities and differences of the innervation of the GTO, compared with other mechanoreceptors, are discussed.
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  • 99
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The vaginal epithelium of the normal estrous mouse shows narrow intercellular spaces, many cytoplasmic fibrils and a continuous basal lamina. At 100 days of age, the vaginal epithelium of mice which had received 5 or 20 μg estradiol-17β, 20 μg ovine prolactin, or 5 μg estradiol-17β + 20 μg prolactin within the first few days of postnatal life, shows wider intercellular spaces in the middle epithelial layers than occur in normal estrous mice. In addition, the mice receiving 20 μg estradiol-17β show prominent intercellular spaces in the basal cell layer and interruptions in the basal lamina, which permit penetration of cytoplasmic processes into the subjacent connective tissue. The relevance of these findings to vaginal carcinogenesis is considered.
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  • 100
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    The @Anatomical Record 179 (1974) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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