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  • Articles  (33)
  • Light and electron microscopy  (23)
  • Aktivierungsanalyse, Neutronen  (10)
  • Springer  (33)
  • 2020-2020
  • 1970-1974  (33)
  • 1945-1949
  • 1973  (33)
Collection
  • Articles  (33)
Source
Keywords
Publisher
  • Springer  (33)
Years
  • 2020-2020
  • 1970-1974  (33)
  • 1945-1949
Year
Topic
  • 1
    Electronic Resource
    Electronic Resource
    Comparative ultrastructural study of normal and grafted skin in the frog,Rana pipiens, with special reference to neuroepithelial connections (1973)
    Springer
    Cell & tissue research 139 (1973), S. 451-462 
    Details
    ISSN: 1432-0878
    Keywords: Skin ; Anurans ; Regional differences in grafts ; Neuroepithelial relationships ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Recent investigations have suggested specific differences in back and belly skin in anurans which appear to influence the quality of reflex responses obtained from various areas of the animals body. The present investigation represents a comparative morphological study of back and belly skin in control and skin-graftedRana pipiens, with special regard to the neuroepithelial relationships. A distinct difference in pigmentation of back and belly skin was observed. Intra-epithelial Merkel cells were present in all skin samples studied. The origins of the numerous unclassifiable cells in the Merkel cell region are discussed in relation to a presumed coordinating function of the Merkel cell during epithelial differentiation. Epitheliomesenchymal interactions were observed in the richly innvervated dermal regions. Two types of morphologically different intra-epithelial nerve endings were observed. These observations are discussed in relation to earlier observations on vertebrate skin and in relation to misdirected reflex responses obtained in skin-grafted anurans.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02028387
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  • 2
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    Electronic Resource
    Structural changes of drosopterinosomes (red pigment granules) during the erythrophore differentiation of the frog, Rana japonica, with reference to other pigment-containing organelles (1973)
    Springer
    Cell & tissue research 137 (1973), S. 331-343 
    Details
    ISSN: 1432-0878
    Keywords: Pigment cells ; Pterinosomes ; Skin ; Rana japonica ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Structural changes in drosopterinosomes (red pigment granules) of Rana japonica in the process of erythrophore differentiation were studied by light and electron microscopy. On the basis of the degree of pterinosome differentiation, three types can be recognized: Typ-I drosopterinosomes appear first during metamorphosis and have clear limiting membranes and amorphous materials within. Those of type-II are found in abundance shortly after metamorphosis and have inner structures, consisting of fibrillae and/or small lamellae in dense concentric arrangement. Type-III is found abundantly in adults and acquires an almost homogeneously electron-dense mature morphology, probably from the deposition of electron-dense materials. On the basis of counts of pterinosomes, a successive transformation from type I to III is suggested. The differences among red drosopterinosomes, yellow sepiapterinosomes in xanthophore and melanosomes are not always distinguishable electron microscopically. Discrimination is possible by careful examination of lamellar patterns characteristic of the respective granules and by a simultaneous application of light and electron microscopy. From this viewpoint, a re-evaluation of the identification of granules previously reported was effected.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307207
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  • 3
    Electronic Resource
    Electronic Resource
    Ultrastructural investigation of the postnatal development of the hamster harderian gland (1973)
    Springer
    Cell & tissue research 142 (1973), S. 1-12 
    Details
    ISSN: 1432-0878
    Keywords: Harderian gland ; Hamster ; Sexual dimorphism ; Alveolar cells ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The lobules of the Harderian glands of young male and female hamsters are widely separated by connective tissue and are made up of alveolar cells containing small vacuoles. There is considerable increase in the size of the lobules by 12 days. Based on size distribution of vacuoles two types of alveolar cells can be recognized in the male hamsters 4 weeks and older. The Harderian glands of 2-week animals of both sexes contain a black-brown pigment. The appearance of pigment is accompanied by a proliferation of membranes. In the female the amount of pigment increases with increasing age until 4 weeks of age and then remains at a relatively stable level. In the male no pigment was found after 4 weeks of age. Membrane-bounded juxtanuclear structures are present in the alveolar cells of both sexes until 3 weeks of age. These structures appear to play different roles in the male and female hamsters. The differentiation of the alveolar cells into light and dark types must take place during the 3rd week of postnatal development. A possible relationship between the levels of gonadal hormones and the occurrence of pigment at different ages in both sexes is also discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00306700
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  • 4
    Electronic Resource
    Electronic Resource
    The structural organization of glomerular neuropile in the olfactory and accessory lobes of an Australian freshwater crayfish, Cherax destructor (1973)
    Springer
    Cell & tissue research 142 (1973), S. 37-61 
    Details
    ISSN: 1432-0878
    Keywords: Crustacean CNS ; Olfactory and accessory lobes ; Glomerular neuropile ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The olfactory and accessory lobes of the crayfish, Cherax destructor contain glomeruli. Light microscope and electron microscope studies show that these glomeruli are the only regions of synaptic activity in the lobes and that at least four separate sets of axons meet within the glomeruli. The olfactory glomeruli are column shaped, complex structures with no large single pre- or postsynaptic elements. The accessory lobe glomeruli follow a more conventional pattern and each has one large axon ending in a terminal arborization where it makes synaptic contact with large numbers of smaller fibres. The large fibre is presynaptic.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00306703
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  • 5
    Electronic Resource
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    Pigment movements in fish melanophores: Morphological and physiological studies (1973)
    Springer
    Cell & tissue research 147 (1973), S. 127-148 
    Details
    ISSN: 1432-0878
    Keywords: Melanophores (Teleost) ; Pigment migration, microtubules ; Colchicine, vinblastine ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The antimitotic drugs colchicine and vinblastine were applied to the melanophores of isolated scales of Pterophyllum scalare. The time course of inhibition of pigment migrations was studied quantitatively with the photoelectric method. Within one hour of treatment with 5 mM colchicine, a partial and reversible inhibition of pigment movements is obtained. During this time, the number of microtubules per cell process does not differ significantly from controls when pigment is dispersed. However, their number increases concomitantly with the decrease in rate of aggregation induced by KCl up to about the same value as in dispersed pigment cells. This indicates a close connection between pigment movements and the microtubule turnover known to occur in angelfish melanophores. When applied in a concentration of 0,2 mM, vinblastine has a total and irreversible effect on pigment movements, with an especially rapid and profound inhibition of pigment dispersion. The fine structure of vinblastine-treated melanophores is characterized by an almost complete loss of microtubules and the appearance of crystalloid bodies, which differ in fine structure from vinblastine-induced crystals of all other cell types so far examined. Possibly their peculiar structure is related to special properties of melanophore microtubules, such as rapid turnover and relatively high resistance to colchicine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00306604
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  • 6
    Electronic Resource
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    The structure of the gills of the elasmobranch, Scyliorhinus canicula (L.) (1973)
    Springer
    Cell & tissue research 144 (1973), S. 489-509 
    Details
    ISSN: 1432-0878
    Keywords: Gills ; Scyliorhinus canicula ; Circulation sphincters ; Hydrostatic skeleton ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The anatomy of the blood supply to the gills of the dogfish, Scyliorhinus canicula, is described. The anatomical basis for a counter-current exchange system at the respiratory surfaces is reported. Within the interbranchial septum there is a capillary network joining all the afferent branchial arterioles of the gill. The structure of the walls of the corpus cavernosum is found to be of smooth muscle cells supported by a basal lamina and connective tissue and lined by endothelial cells containing phagocytic vesicles. Both the capillary network and corpus cavernosum are suggested to function in smoothing the pressure pulses of the blood flow. Pre- and post-lamellar vessels and pre- and post-lamellar sphincters are described. The sphincters are thought to control the number of secondary lamellae physiologically in the respiratory circuit, and by retaining blood within nonperfused lamellae to act in conjunction with pillar cells (contracting in antagonism to the hydrostatic skeleton of the blood) to maintain the rigidity of secondary lamellae in the water current. Whorls of cells of unknown function are found within the interbranchial septum. In the epithelium lining the water channel large cells having a complexly branching plasma membrane and a very large central vacuole occurs. The cytoplasm lining the lumen contains numerous vacuoles each surrounded by a double membrane.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307376
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  • 7
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    Histological and ultrastructural studies of the basal disk of Hydra (1973)
    Springer
    Cell & tissue research 139 (1973), S. 1-27 
    Details
    ISSN: 1432-0878
    Keywords: Glandulomuscular cells ; Hydra ; Basal disk ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The glandulomuscular cells of Hydra are located exclusively in the basal disk. They are derived from epithelio-muscular cells which have been forced proximally. Light and electron microscopical studies show that prior to their destruction and elimination, the transformed epithelio-muscular cells (i.e. the glandulomuscular cells) undergo certain striking morphological and physiological changes. Golgi complexes and elements of rough E. R. increase remarkably in activity, and individually or jointly produce at least six types of morphologically different droplets. One additional type of droplet is thought to originate from neighboring digestive cells. Although the chemical nature of the individual droplets is uncertain, it is known that some are Alcian blue and PAS positive and contain hyaluronic acid. These evidences suggest the presence of an acid mucopolysaccharide material, the adhesive agent which attaches the animal to a substrate. The myonemes contain thick (200 Å in diameter) and thin (60 Å in diameter) filaments as in epithelio-muscular cells. There are also filaments of intermediate sizes and large fibers (770 Å in diameter). The myonemes are oriented radially with respect to the aboral pore and therefore in addition to contributing to the contraction and relaxation of the body column, they apparently regulate the opening and closing of the aboral pore. Although there is no evidence to substantiate the mechanism for transformation of epithelio-muscular cells to glandulomuscular cells as well as cell death of the latter cell types, these problems are discussed briefly.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307458
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  • 8
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    Histological and ultrastructural studies of the basal disk of Hydra (1973)
    Springer
    Cell & tissue research 139 (1973), S. 29-45 
    Details
    ISSN: 1432-0878
    Keywords: Nerve cells ; Hydra ; Basal disk ; Epithelial cells ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In addition to glandulomuscular cells, three other cell types are found in the basal disk of Hydra. These are interstitial cells, cnidoblasts and nerve cells. Although only a few of the two former cell types are recognized in this region, the observations from this study refute previous statements to the contrary. Nerve cells are concentrated in the basal disk where they form a type of “network” system, due to the presence of bipolar, tripolar and multipolar cells. In some specimens, they assume a circular arrangement around the base of the polyp. Using morphological criteria for identifying the three types of epidermal nerve cells (neurosensory, neurosecretory and ganglionic) in other body regions, only neurosensory and neurosecretory cells are observed in the basal disk. These are indistinguishable ultrastructurally from their respective counterparts in other regions. It is possible that ganglionic cells are also present in the basal disk, but there may be few such cells. It is suggested that the three cell types originate from the budding region and these precursor cells are then forced proximally. Interstitial cells, escaping their differentiative function, do not develop apparently into other cell types of the basal disk. Cnidoblasts contain normal nematocysts but their functional ability is uncertain. Neurosensory and neurosecretory cells arise directly and independently from interstitial cells in the budding region, as evidenced by the appearance of immature nerve cells in the peduncle and their absence in the basal disk. Although viable cells may be discarded from the basal disk, it is believed that most cells die in situ and are then eliminated. The possible role of nerve cells is discussed briefly.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307459
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  • 9
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    The ultrastructure of the caecal epithelium of the intraredial cercaria of Neophasis lageniformis (Lebour, 1910) (Trematoda, Acanthocolpidae) (1973)
    Springer
    Cell & tissue research 139 (1973), S. 405-416 
    Details
    ISSN: 1432-0878
    Keywords: Caecal epithelium ; Trematodes, Cercariae ; Extracellular membranes, Membranous whorls ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The intestinal caeca of the intraredial cercaria of Neophasis lageniformis differ in several aspects from previous descriptions of the intestinal caeca of other digenetic trematodes. The caeca are lined with a single-layered, non-syncytial epithelium with lamellate projections into the lumen. The cells are rich in glycogen particles and contain abundant granular endoplasmic reticulum. The apical cell membrane, which displays a unit membrane structure, is always covered by an external membrane of the same thickness as a unit membrane but showing no double-layered substructure. The external membrane, which is not equivalent to a glycocalyx, may continue from one cell to another. Apically on the projections the external membranes are apparently pushed out forming large, extracellular whorls, which fill up the caecal lumen. In the lumen there are also found crystal-like structures and lipid-like bodies which are suspended in a granular substance. The possible origin and function of the extracellular bodies are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00306594
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  • 10
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    Ultrastructure de l'œuf de Triatoma infestans Klug (1973)
    Springer
    Cell & tissue research 138 (1973), S. 113-132 
    Details
    ISSN: 1432-0878
    Keywords: Eggs ; Insects (Triatoma infestans) ; Embryogenesis ; Envelopes, Permeability ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The thick rigid chorion of the egg of Triatoma secreted by the follicle cells shows two porous layers: an aerial layer in the exochorion, an alveolar one in the endochorion. The anterior part of the eggshell is closed up by an operculum which is heaved up by the hatching larva. The operculum has no alveolar layer. The air enters through the numerous holes of the shell surface into the aerial layer and through the micropyles into the alveolar layer. The egg has no respiratory plastron. The follicle cells produce also a vitelline envelope whose structure shows a rapid condensation at fertilization time. During its development the embryo secretes two layers: serosal and embryonic cuticle. At high humidities, at low temperatures the egg is able to increase its weight during the early stages of embryogenesis, and this increase stops when the serosal cuticle is secreted. In a dry atmosphere the egg loses water but can develop if the temperature is higher than 20°C. The little permeability of the egg is related to the structure of its envelopes. The chorion and the vitelline envelope prevent the water from getting out of the egg. The serosal cuticle seems to be opposed to the penetration of the water into the egg. The role of the embryonic cuticle is probably limited in the transit of water.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307082
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  • 11
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    Studies on the acetylcholinesterase (ache)-positive and -negative autonomic axons supplying smooth muscle in the normal and 6-hydroxydopamine (6-OHDA)treated rat iris (1973)
    Springer
    Cell & tissue research 138 (1973), S. 211-222 
    Details
    ISSN: 1432-0878
    Keywords: Iris ; Muscle, Nerves ; Light and electron microscopy ; Acetylcholinesterase ; 6-Hydroxydopamine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The adrenergic and cholinergic innervation to the rat iris has been studied at a light and electron microscopic level. Catecholamine fluorescence histochemistry showed adrenergic nerves to be present in both the dilatator and the constrictor pupillae regions. At a fine structural level the terminal innervation of the iris was studied and criteria for the differentiation between presumptive adrenergic and presumptive cholinergic axon terminals were examined. To aid this examination presumptive adrenergic axons were either labelled with the “false” adrenergic transmitter, 5-hydroxydopamine, or chemical sympathectomy performed using 6-hydroxydopamine. The value of using acetylcholinesterase staining as a marker for cholinergic nerve terminals was also studied. Results showed a mixed adrenergic/cholinergic innervation to the dilatator pupillae. In the constrictor pupillae an exclusively cholinergic innervation was found although adrenergic and cholinergic nerves were found supplying the blood vessels and at the dilatator-constrictor interface. These findings are discussed with regard to innervation-function relationships in the iris.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00306608
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  • 12
    Electronic Resource
    Electronic Resource
    Extrinsic innervation of olfactory epithelium (1973)
    Springer
    Cell & tissue research 138 (1973), S. 315-326 
    Details
    ISSN: 1432-0878
    Keywords: Olfactory mucosa ; Frog ; Innervation ; Ultrastructure ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The olfactory mucosa of frog has been studied at an ultrastructural level to confirm previous light microscope observations in regard to the presence, in the sensory epithelium, of nerve fibres not belonging to the first cranial nerve proper. It has been observed that both myelinated and unmyelinated nerve fibres are present in the lamina propria and that eventually these fibres terminate inside the epithelium. Unmyelinated fibres usually contain dark core vesicles and similar content is seen in their intraepithelium terminals. Terminals containing only clear vesicles are also observed in the epithelium and they are believed to represent the terminals of the myelinated fibres. The significance of these ultrastructural findings is discussed in view of their functional meaning.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307095
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  • 13
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    The neurohypophysis of the crested newt (1973)
    Springer
    Cell & tissue research 141 (1973), S. 203-221 
    Details
    ISSN: 1432-0878
    Keywords: Median eminence ; Newt ; Zones ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the median eminence of the newt a medial region and two lateral regions are described. In cross section, the medial region appears to be made up of 1) an outer or glandular zone (Zone I) containing aldehyde-thionine-positive and negative nerve fibres and blood capillaries. Nerve fibres appear aligned in palisade array along the capillaries. 2) An inner zone (Zone II) made up of a) a layer of aldehyde-thionine-positive nerve fibres (fibrous layer) belonging to the preoptic hypophyseal tract and b) a layer of ependymal cells lining the infundibular lumen and reaching the blood vessels with their long processes. The lateral regions display a less pronounced stratification and aldehyde-thionine positive nerve fibres are nearly absent. A slender lamina (ependymal border) containing mainly aldehyde-thionine-positive nerve fibres and ependymal cells connects the median eminence to the pars nervosa. At the ultrastructural level, in the outer zone of the medial region at least 4 types of nerve fibres and nerve endings are identified: Type I nerve fibres containing granular vesicles of 700–1000 Å and clear vesicles (250–400 Å). Type II nerve fibres containing granular vesicles and polymorphous granules of 900–1300 Å and clear vesicles (250–400 Å). Type III nerve fibres containing dense granules of 1200–2000 Å and clear vesicles of 250–400 Å. Type IV nerve fibres containing only clear vesicles of 250–400 Å. In the inner zone too, all these nerve fiber types are found among ependymal cells, while the fibrous layer consists of nerve fibres containing granules of 1200–2000 Å in diameter. In the lateral regions Type I, Type II and Type IV nerve fibres and their respective perivascular terminals are found; axons containing dense granules (1200–2000 Å) are scanty. In these regions typical synapses between Type I nerve fibres and processes rich in microtubules are visible. The classification and functional significance of nerve fibres in the median eminence are still unsolved, but it may be assumed that nerve fibres of the medial region belong to both the preoptic hypophyseal and tubero hypophyseal tract, while the lateral regions are characterized by nerve fibres of the tubero hypophyseal tract. Peculiar specializations of the ependymal cells in the median eminence of the newt are also discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00311354
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  • 14
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    The outgrowth of rat cerebellum in organized culture (1973)
    Springer
    Cell & tissue research 146 (1973), S. 45-67 
    Details
    ISSN: 1432-0878
    Keywords: Cerebellum (rat) ; Growth in Tissue culture ; Cell types ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The outgrowth of newborn rat cerebellum cultivated in the Maximow assembly was studied from the time of explanation until the end of the 1st week “in vitro”. Dynamic characteristics of migrating cells were investigated with time lapse microcinematography and with phase and interference contrast. Three types of cells were identified: bipolar fusiform cells, fibroblasts and macrophages. The ultrastructure of these cells as seen with scanning and transmission electron microscopes is described. Bipolar cells display the same characteristics as those of migrating granule cells “in vivo”. Differentiation of these cells towards neuronal types becomes evident at the end of the first week “in vitro”. Axonal as well as dendritic growth cones were examined, and their ultrastructural characteristics described. Attention is focussed into the abundance of smooth endoplasmic reticulum, which in supposed active growth has the form of thin cisternae, and, at rest or in retraction takes the form of large vesicles. In the latter case, filopodia disappear, and the tips of their processes acquire a bulbous shape.
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    URL: http://dx.doi.org/10.1007/BF00306758
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  • 15
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    La glande coquillière non pigmentée d'Artemia salina Leach (1973)
    Springer
    Cell & tissue research 144 (1973), S. 299-308 
    Details
    ISSN: 1432-0878
    Keywords: Shell glands ; Artemia salina ; White and brown glands ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Ce travail concerne l'étude morphologique de la glande coquillière non pigmentée ou blanche d'Artemia salina. La structure de celle-ci est comparée à celle de la glande coquillière brune de la même espèce. Les différences sont apparemment plus fondamentales qu'une simple variation de la quantité de produit de sécrétion ou de la pigmentation des cellules. Là où les glandes coquillières brunes formeraient la coque chez les animaux ovipares les glandes coquillières blanches pourraient sécréter les produits nécessaires ou utiles au développement des nauplii chez les animaux ovovivipares.
    Notes: Summary The white shell glands of Artemia salina have been investigated. Our results, compared to those obtained in the brown-coloured shell glands, occuring within the same species, reveal differences not only in the aspect of the secretory granules but also in the structure of the nucleus and the cytoplasm. These differences between the two types of glands appear to be more striking than a simple variation in the quantity of secretion or in the pigmentation of the gland. As the brown glands are supposed to contribute to the formation of the egg shells in oviparous animals, the secretion of white glands could favour the development of nauplii in ovoviviparous animals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307306
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  • 16
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    Effets de modifications de la composition électrolytique du plasma sur la structure et la fonction des cellules interrénales (corticosurrénaliennes) d'un Amphibien Urodèle: Triturus cristatus (1973)
    Springer
    Cell & tissue research 139 (1973), S. 47-59 
    Details
    ISSN: 1432-0878
    Keywords: Adrenocortical cells ; Triturus cristatus ; Plasma electrolyte composition modifications ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Dans le but de modifier la composition électrolytique du plasma, des Tritons à crête (Triturus cristatus) sont placés dans une solution de chlorure de potassium (KCl 5‰). D'autres Tritons (témoins) sont placés dans de l'eau du robinet. Tous les animaux ont été préalablement hypophysectomisés. 8 jours après le début de l'expérience, les cellules interrénales des Tritons hypophysectomisés placés dans la solution de KCl présentent une activité stéroidogénique élevée, se traduisant notamment par une forte déplétion lipidique, une augmentation du nombre des mitochondries et un développement important du réticulum endoplasmique agranulaire et tubulaire; d'autre part, la réaction Δ5-3β-hydroxystéroide deshydrogénasique est intense. Toutes les cellules du tissu interrénal sont fortement stimulées dans ces conditions. Les cellules interrénales des Tritons témoins présentent par contre une activité stéroidogénique très réduite, comme en témoignent leur structure et la faible intensité de la réaction Δ5-3β-hydroxystéroide deshydrogénasique. Les mécanismes précis pouvant être à l'origine de la stimulation des cellules interrénales de Tritons hypophysectomisés placés dans la solution de KCl sont discutés.
    Notes: Summary In order to induce a modification of the plasmatic electrolyte composition, newts (Triturus cristatus) are placed into a potassium chloride solution (KCl 5‰), while controls are kept in tap water. All animals are previously hypophysectomized. 8 days after the beginning of the experiment, the interrenal cells of the hypophysectomized newts kept in KCl solution exhibit a very strong steroidogenic activity, as evidenced by a striking lipid depletion, an increase in the number of mitochondria and a considerable development of the agranular tubular endoplasmic reticulum. On the other hand, the Δ5-3β-hydroxysteroid dehydrogenase reaction is notably intensified. All the cells of the interrenal tissue are affected by the stimulatory effect of the KCl solution. Control animals show only reduced steroidogenic activity of their interrenal cells, as demonstrated both by the morphology of these cells and the weak Δ5-3β-hydroxysteroid dehydrogenase reaction. The mechanisms involved in the stimulatory effect on steroidogenesis of the variation of the electrolyte composition of the plasma are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307460
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  • 17
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    Orthogonal microvillus pattern in the eighth rhabdomere of the rock crab Grapsus (1973)
    Springer
    Cell & tissue research 137 (1973), S. 145-157 
    Details
    ISSN: 1432-0878
    Keywords: Rhabdom ; Photoreceptor fine structure ; Rhabdomere microvillus pattern ; Crustacean compound eye ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The eighth retinular cell (R 8) of Grapsus lacks cytoplasmic pigment granules and basically resembles those previously known in the ghost crab Ocypode and the mysid Praunus. Distally located, R 8 comprises four lobes inserted between the outer ends of the seven regular retinular cells (R 1–R 7). A thin cytoplasmic bridge connects these lobes. One lobe adjacent to R 1 contains the nucleus of R 8 and gives rise proximally to the cell's axon. The short distal eighth rhabdomere consists of microvilli (mvl) protruding axially from all four lobes. Similar R 8's were found also in two other crab families and in two other genera of mysids. In Grapsus the eighth rhabdomere is extraordinary in possessing mvl oriented in two orthogonal directions parallel to the mvl of R 1–R 7. The distal 20% of the rhabdom consists of mvl originating exclusively from R 8. These appear in somewhat irregular bands and are alternately oriented parallel to the animal's vertical or horizontal axis. More proximally the retinula contains eleven sectors but the rhabdom still comprises bands of alternating mvl with those from R 8 joined respectively by the rhabdomeres of R 1, 4, and 5 (horizontal) and R 2, 3, 6 and 7 (vertical). The rest of the rhabdom shows typical decapod organization with seven interdigitating rhabdomeres.
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    The structure of the gill of the trout, Salmo gairdneri (Richardson) (1973)
    Springer
    Cell & tissue research 142 (1973), S. 147-162 
    Details
    ISSN: 1432-0878
    Keywords: Gill ; Blood pathways ; Secondary lamellae ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A light and electron microscopic study was made of the structure of the gill arch, filament and secondary lamella of Salmo gairdneri R. Blood pathways through the gill were traced from serial histological sections, and from the examination of ink perfused tissue and perspex casts formed following resin injection of the circulatory system. The epithelium covering the gill consists of unspecialized, dark, chloride and mucous cells. The distribution of specialized cells appears to be related to gill function. The basement membrane underlying the epithelium consists of three layers, the inner collagen layer being continuous with the connective tissue core of the gills. Blood supply to the secondary lamellar respiratory surface is via branchial, filament and secondary lamellar arteries. Blood spaces of the secondary lamellae are delimited by pillar cells containing what appears to be contractile material. The marginal channel of each lamella is bounded distally by cells of endothelial origin. A network of lymph spaces within the filaments connects with efferent branchial arteries. Nutritionary capillaries within the filaments connect with afferent branchial arteries. No shunts between afferent and efferent filament arteries were found. Data from this study and previous physiological and histopathological studies suggest a mechanism for the control of blood flow to suit the respiratory requirements of the fish. This mechanism involves a system of recruitment of additional respiratory units and changes in overall blood flow patterns.
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    URL: http://dx.doi.org/10.1007/BF00307029
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  • 19
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    Fine structural studies of rat adrenal cortices following prostaglandin administration (1973)
    Springer
    Cell & tissue research 146 (1973), S. 297-307 
    Details
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Prostaglandins E1 and E2 ; Fine structure ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Histological and fine structural studies of adrenal cortices were performed on male Sprague-Dawley rats which had been given intravenous injections of prostaglandin E1 or E2. It was found that there were increased numbers of intracellular lipid droplets, free ribonucleoprotein particles, cholesterol ester clefts and coated vesicles of both the small and large varieties. A reorganization of the internal mitochondrial membranes and the appearance of protrusions of parenchymal cytoplasm into the sinusoidal lumina accompanied by vasodilation were also observed. These alterations are not typical of those observed following exogenous ACTH administration and are therefore considered to be prostaglandin-induced.
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    URL: http://dx.doi.org/10.1007/BF02346222
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  • 20
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    Responses of prolactin cells of two euryhaline marine fishes, Gillichthys mirabilis and Platichthys stellatus, to environmental salinity (1973)
    Springer
    Cell & tissue research 136 (1973), S. 153-167 
    Details
    ISSN: 1432-0878
    Keywords: Prolactin ; Adenohypophysis ; Osmoregulation ; Teleosts ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Changes in the prolactin cells of the euryhaline marine teleosts Gillichthys mirabilis and Platichthys stellatus were studied by light and electron microscopy after transfer from sea water to fresh water. In seawater fish the secretory granules were smaller and the cellular organelles poorly developed. Within 3 hours after transfer to fresh water, the prolactin cells of Gillichthys exhibited definite functional activation: exocytosis of granules and development of rough endoplasmic reticulum (RER), Golgi systems and mitochondria. Concurrently, plasma sodium fell from about 172 meq/l to about 133 meq/l. As adaptation to fresh water progressed, prolactin cells of Gillichthys showed greater prominence of cellular organelles but granule storage was not detected even 10 days after transfer. Platichthys adapted to fresh water for 10 days showed RER in an expanded state containing irregular electron-dense material which was not seen in Gillichthys. Plasma sodium levels were much lower than in the controls. These results were in contrast to those obtained from euryhaline freshwater fishes such as Poecilia and Oryzias. Although the prolactin cells of euryhaline marine fish exhibited intense secretory activity when transferred into fresh water, the secreted prolactin per se appeared to be insufficient to maintain plasma sodium at seawater levels.
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  • 21
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    Rectal ultrastructure in salt- and freshwater mosquito larvae in relation to physiological state (1973)
    Springer
    Cell & tissue research 138 (1973), S. 1-22 
    Details
    ISSN: 1432-0878
    Keywords: Mosquitoes-Aedes ; Rectum ; Fine structure, function, comparison ; Salt-adaptation, osmoregulation ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A comparison of rectal morphology and ultrastructure is made between a freshwater (A. aegypti) and salt water (A. campestris) species of mosquito larvae, and between A. campestris larvae producing hyper- and hyposmotic urine. The epithelium of A. aegypti contains one cell type characterized by infolding of both the apical and basal membranes, straight lateral borders, and evenly distributed mitochondria. The rectum of A. campestris contains distinct anterior and posterior regions, each made up of a single cell type. These two regions can be distinguished on the basis of cell thickness, depth of apical infolding and distribution of mitochondria. The anterior region is similar to the rectum of A. aegypti, while the posterior region is considered unique to the salt-water species and hence probably is associated with the formation of hyperosmotic urine. In A. campestris, the apical (rather than lateral or basal) membranes are probably the site of hyperosmotic urine production. Two possible mechanisms for this process are discussed.
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    URL: http://dx.doi.org/10.1007/BF00307074
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  • 22
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    Elektronenmikroskopische Untersuchungen über die Zytoarchitektur des Gehirns vonBranchiostoma lanceolatum (1973)
    Springer
    Cell & tissue research 139 (1973), S. 511-532 
    Details
    ISSN: 1432-0878
    Keywords: Brain ; Cytoarchitecture ; Branchiostoma ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Gehirn vonBranchiostoma lanceolatum wurde licht- und elektronen-mikroskopisch untersucht. Der rostral gelegene Ventrikel wird von unterschiedlich gebauten, prismatischen Epithelzellen umgeben, unter denen neben den Pigmentzellen und den sekret-bildenden Infundibulumzellen vor allem dorsal und ventral gelegene Elemente mit ungewöhnlich langen, zilienähnlichen apikalen Fortsätzen auffallen, die vermutlich Rezeptorzellen entsprechen. Nach caudal schließt sich dem Ventrikel der schmale Zentralkanal an, der von Tanyzytengliazellen ausgekleidet wird. Ihre basalen filamenthaltigen Fortsätze ziehen bis zur Oberfläche des ZNS und bilden hier Füßchen aus. Zwischen diesen Ependymzellen erreichen apikale Fortsätze von tiefergelegenen Zellen das Lumen des Zentralkanals. Die Zahl der um den Zentralkanal gelegenen Neurone nimmt im Gehirn von rostal nach caudal ab. Die Perikaryen dieser Neurone sind vor allem durch ihren hohen Gehalt an Glykogen und verhältnismäßig zahlreichen granulären Einschlüssen gekennzeichnet. Eine ventral gelegene Gruppe von großen, ergastoplasmareichen Nervenzellen enthält relativ große Granula, die vermultlich neurosekretorischen Elementargranula entsprechen. Dorsal kommen neben den großen Josephschen Zellen ependymale Zellen vor, deren Zellapex mit zahlreichen Lamellen versehen ist. Auch sie stellen vermutlich Lichtrezeptoren dar. Das peripher lateral und ventral gelegene Neuropil setzt sich aus Fasern zusammen, die nicht von den Gliazellen umgeben sind und die in ihrer Mehrzahl Granula enthalten. Es werden 6 (?) Granulatypen unterschieden. Außerdem lassen sich vor allem in der Peripherie Fasern mit Mikrotubuli und Filamenten erkennen. Die Riesenfasern enthalten außer einzelnen Organellen unstrukturiert erscheinendes Zytoplasma. Synapsenähnliche Kontakte sind relativ selten und einfach gebaut.
    Notes: Summary The brain ofBranchiostoma lanceolatum has been investigated with the light-and electron microscope. The cranially located ventricle is surrounded by various types of prismatic epithelial cells among which—beside the anterior pigment-cells and the mucus producing infundibular cells—elements bearing unusually long apical cilium-like processes are particularly striking. They can be found in the dorsal and ventral wall of the ventricle and presumably represent receptor cells. The ventricle is caudally replaced by the narrow central canal which is lined by tanycyte-like glia cells, whose filamentous basal processes reach the surface of the CNS where they terminate in broad foot-like structures. Between these ependymal cells apical processes of light, granule-containing cells reach the lumen of the central canal. The number of neurons which are all concentrated around the central canal, decreases in caudal direction. Their perikarya are characterized by granular inclusions and large amounts of glycogen particles. A ventrally situated group of big ER-rich neurons contains granules which presumably correspond to neurosecretory elementary granules. Dorsally beside the large Joseph-cells lamellated cells occur, which possibly also represent lightreceptor cells. The neuropile which predominantly occurs in the lateral and ventral and ventral periphery of the CNS consists of densely packed fibres which are not surrounded by glia cells and the majority of which contains granular or vesicular inclusions. 6 (?) types of granules and vesicles are to be distinguished. In addition, fibres containing microtubules and filaments occur. They are mainly to be found in a marginal position. The giant fibres contain beside scarce organelles structureless light cytoplasm. Synaptoid contacts are comparatively rare and of simple structure.
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    Nigro-neostriatal projection (1973)
    Springer
    Cell & tissue research 138 (1973), S. 333-344 
    Details
    ISSN: 1432-0878
    Keywords: Substantia nigra and striatum (rat, cat) ; Stereotactic electrolysis ; Degeneration ; Dopamine fluorescence ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The nigro-neostriatal projection was investigated in albino rats and cats with silver impregnation, fluorescence histochemistry and electron microscopy. After unilateral stereotactic electrolysis in the substantia nigra the dopamine fluorescence of ipsilateral neostriatum is markedly reduced. As shown by silver impregnation and electron microscopy, fine terminals and axons are degenerated in the same region. These observations suggest that the nigro-neostriatal pathway may be composed of the fine dopaminergic axons of the nerve cells of unilateral substantia nigra.
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    URL: http://dx.doi.org/10.1007/BF00307097
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    Bestimmung des Urangehaltes von Erzproben durch Neutronenaktivierung (1973)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 263 (1973), S. 108-110 
    Details
    ISSN: 1618-2650
    Keywords: Best. von Uran in Erzen ; Aktivierungsanalyse, Neutronen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Zur aktivierungsanalytischen Bestimmung von Uran in Erzen werden die Proben 5 h bei einer Neutronenflußdichte von 5,4 · 109 s−1 cm−2 bestrahlt und nach 48 h die Aktivität γ-spektroskopisch mit Hilfe eines Ge-Li-Detektors gemessen. Zur Messung dienten die 228 und 277 keV-Gammalinien von Np-239. Die Ergebnisse zeigen gute Übereinstimmung mit den nach anderen Methoden erhaltenen.
    Notes: Abstract The samples are activated within 5 h by a neutron flux of 5.4×109 sec−1×cm−2. After 48 h the activity is measured by γ-spectroscopy employing a Ge-Li detector. The 228 and 277 keV γ-lines of Np-239 are used for the determination. The agreement of the results with those obtained by other methods is good.
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    Instrumentelle Neutronenaktivierungsanalyse von Gesteinen am Beispiel von 7 Standardgesteinen des US Geological Survey (1973)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 263 (1973), S. 100-107 
    Details
    ISSN: 1618-2650
    Keywords: Analyse von Gesteinen ; Aktivierungsanalyse, Neutronen ; US-Standardgesteine als Multielementstandards
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Mit Hilfe instrumenteller Neutronenaktivierungsanalyse wurden in den Standardgesteinen G-2, GSP-1, AGV-1, PCC-1, DTS-1, BCR-1 und W-1 des US Geological Survey die Elemente Sc, Cr, Co, Rb, Sb, Cs, La, Ce, Nd, Eu, Tb, Yb, Lu, Hf, Ta und Th bestimmt und mit den Ergebnissen anderer Autoren verglichen. Die Gesteinsstandards sind bezüglich ihrer Spurenelementverteilung hinreichend homogen, um bei der Analyse von geologischem Material in den meisten Fällen als Multielementstandards verwendet werden zu können.
    Notes: Abstract By means of instrumental neutron-activation analysis the elements Sc, Cr, Co, Rb, Sb, Cs, La, Ce, Nd, Eu, Tb, Yb, Lu, Hf, Ta, and Th were determined in the standard rocks G-2, GSP-1, AGV-1, PCC-1, DTS-1, BCR-1, and W-1 of the US Geological Survey. The results were compared with those of other authors. These standard rocks are sufficiently homogeneous, as regards their trace element distribution, to be used as multielement standards in most analyses of geological material.
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    Determination of rare earth element distribution patterns in rocks and minerals by neutron-activation analysis (1973)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 263 (1973), S. 97-100 
    Details
    ISSN: 1618-2650
    Keywords: Best. von Seltenen Erden in Gesteinen und Mineralien ; Aktivierungsanalyse, Neutronen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary A routine procedure for determining eleven of the fourteen naturally occurring rare earth elements (REE) in rocks and minerals is described. Following thermal neutron activation the samples are decomposed, in the presence of REE carriers, by fusion with Na2O2. The REE are separated as a group using a gel removal technique for silica and a conventional hydroxide-fluoride cycle. The REE concentrates are then counted with a high resolution Ge(Li) spectrometer system. Chemical yields are determined by reirradiation and counting of the carrier. The high precision and accuracy of the technique have been proven through replicate analyses and through analyses of the U.S. Geological Survey standard rock, W-1. The technique, with slight modifications, has been tested to date on more than a hundred rock and mineral samples. Experience has shown that the eleven REE determined by this technique more than adequately describe the total distribution patterns for the REE in naturally occurring samples.
    Notes: Zusammenfassung Ein Routineverfahren für die Bestimmung von 11 Elementen der Seltenen Erden in natürlich vorkommenden Mineralien und Gesteinen wird beschrieben. Die Proben werden mit thermischen Neutronen bestrahlt und anschließend die Substanzen nach Zusatz von Trägerelementen (Seltene Erden) mit, Na2O2 aufgeschlossen. Die Seltenen Erden werden dann als Gruppe mittels eines Hydroxid-Fluorid-Trennverfahrens isoliert. Silicium wird als Gel abgetrennt. Die Messung der Aktivitäten in den Lanthanidenkonzentraten erfolgt mit einer Ge(Li) Gamma-Spektrometer-Meßanordnung hoher Auflösung. Die bei der chemischen Abtrennung der Seltenen Erden erzielte Ausbeute wird anschließend durch Bestrahlung der Anreicherungsprodukte und Messung der Aktivitäten der Trägerelemente bestimmt. Die Reproduzierbarkeit und Genauigkeit der Methode wurde durch die mehrfache Analysierung bestimmter Proben und von Standardgesteinen (z.B. W-1) geprüft. Mit leichten Änderungen wurde das Verfahren an über 100 Gesteins- und Mineralproben erprobt. Es hat sich gezeigt, daß mit den 11 durch Neutronenaktivierung quantitativ bestimmten Seltenen Erden die Verteilung dieser Elementgruppe in natürlich vorkommenden Mineralien und Gesteinen hinreichend gut beschrieben werden kann.
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    Abtrennung von Na, K und P mit Hilfe anorganischer Separatoren bei der Neutronenaktivierungsanalyse von biologischem Material (1973)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 263 (1973), S. 110-115 
    Details
    ISSN: 1618-2650
    Keywords: Abtrenn, von Natrium, Kalium, Phosphor ; von Biolog. Material ; Aktivierungsanalyse, Neutronen ; anorg. Separatoren ; Verwendung von Antimonpentoxid ; zur Abtrenn, von Na aus Biolog. Material ; Verwendung von Zirkoniumphosphat ; zur Abtrenn, von P aus Biolog. Material ; Verwendung von Titanphosphat ; zur Abtrenn, von K aus Biolog. Material
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Zur Entfernung hochaktiver Komponenten aus neutronenaktivierten biologischen Proben wurden 2 Sorptionsprozesse eingehender untersucht. Zur Abtrennung von 24Na wurde unterschiedlich hergestelltes „Hydratisiertes Antimon Pentoxid“ (HAP), für die Abtrennung von 32P Zirkoniumphosphat (ZP) getestet. Für die Abtrennung von 42K wurden handelsübliche Titanphosphatpräparate (TiP) benutzt. Aufgrund der Sorptionsversuche und einiger physiko-chemischer Eigenschaften der Präparate wurden die Parameter zur Herstellung und Anwendung dieser Substanzen optimiert. Durch kombinierte Anwendung von HAP, ZP und TiP waren bei den gewählten Arbeitsbedingungen, z. B. bei aktivierten Kartoffelproben, keine dieser 3 störenden Komponenten nachweisbar. Eine halbautomatische Trennapparatur wurde konstruiert, welche aus folgenden Hauptteilen besteht: Destillationsapparatur, Sorptionskolonne, Ionenaustauschersäule, GradientelutionsAufsatz, elektropneumatische Ventile und Fraktionssammler. Die Aufarbeitung der Probe erfolgt ferngesteuert, der Zeitbedarf beträgt ca. 7 h.
    Notes: Abstract Two sorption processes for the removal of the matrix activity of neutron activated biological samples were investigated in detail. “Hydrated Antimony Pentoxide” (HAP), prepared by various methods, was applied to remove the 24Na, while zirconium phosphate (ZP) was used for the removal of 32P. Commercially available (S.E.R.A.I.) titanium phosphate (TiP) was applied for the retention of 42K. The optimal conditions for preparation and application of these substances were determined by investigation of the sorption parameters and of some physico-chemical properties. Applying the sorption materials HAP, ZP, and TiP under the chosen working conditions, none of the three disturbing activities could be detected in neutron irradiated potato samples. A semiautomatic apparatus was constructed for the dissolution and chemical processing of the irradiated materials, the main parts of which are the following: distillation apparatus, sorption column, ion-exchange column, gradient-elution system, electropneumatical valves, and a fraction collector. The entire chemical processing is carried out by remote control, the time requirement is about 7 h.
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    Neutronenaktivierungsanalytische Bestimmungen von Quecksilbergehalten in diversen Fischproben und anderen biologischen Materialien (1973)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 263 (1973), S. 116-120 
    Details
    ISSN: 1618-2650
    Keywords: Best. von Quecksilber in Biolog. Material, Fisch ; Aktivierungsanalyse, Neutronen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Quecksilbergehlte in verschiedenartigen Fischproben und anderen biologischen Materialien wurden durch die Neutronenaktivierungsanalyse über das Hg-197 bestimmt. Ein in der Literatur beschriebenes Verfahren diente unter Ausnutzung der Flüchtigkeit von Quecksilber(II)-chlorid und der leichten elektrolytischen Abscheidbarkeit des Quecksilbermetalls der unumgänglichen Isolierung der Quecksilberaktivität. Die durch diese Methode nicht bewirkte, jedoch notwendige Abtrennung vom gewöhnlich anwesenden Au-198 wurde durch Verflüchtigung des Quecksilbers als Metall erreicht. Bedenklich hohe Gehalte an Quecksilber ließen sich in einigen japanischen Thunfischkonserven sowie in Weißfischen des Rheins nachweisen.
    Notes: Abstract Mercury contents in diverse samples of fish and other biological materials have been determined by neutron-activation analysis measuring the activity of Hg-197. A method described in literature was used for the indispensable separation of the mercury activity utilizing the volatility of HgCl2 and the low electric potential of deposition of mercury metal. The also required, by this method however not effected separation of Au-198 usually found in the irradiated materials was accomplished by volatilisation of the mercury metal at 850° C. Seriously high contents of mercury were found in some samples of Japanese canned tuna and in whitefish of Rhine river.
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    Neutronenselbstabsorption in der Aktivierungsanalyse (1973)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 263 (1973), S. 194-202 
    Details
    ISSN: 1618-2650
    Keywords: Aktivierungsanalyse, Neutronen ; Untersuchung der Neutronenselbstabsorption
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung In der vorliegenden Studie wurden Modellvorstellungen zur Abschätzung des Einflusses der Selbstabschirmung bei der Bestrahlung mit Neutronen entwickelt. Die genaue Durcharbeitung der Parabelapproximation erlaubt es, den Effekt der Neutronenflußdepression quantitativ zu erfassen, so daß ihr Einfluß in der Praxis der Aktivierungsanalyse berücksichtigt werden kann. Ein Vergleich der vorhegenden Resultate mit Ergebnissen anderer Arbeiten auf praktischem Gebiet zeigt eine sehr gute quantitative Übereinstimmung. Die angegebenen Gleichungen, Diagramme und Tabellen ermöglichen eine Bestimmung der maximalen Flußdepression für jedes praktisch vorkommende Bestrahlungsmaterial mit annähernd bekannter Zusammensetzung.
    Notes: Abstract Models have been developed for the estimation of the influence of self-absorption in the irradiation with neutrons. A parabolic approximation permits the determination of the effect of neutron flux depression, so that its influence in practical activation analysis can be taken account of. Comparison with the results of other workers shows good agreement. The maximum flux depression can be determined by means of the equations, diagrams and tables for any usual material with approximately known composition.
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    Non-destructive neutron activation determination of uranium by the 106 KeV-γ-Peak of neptunium-239 (1973)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 266 (1973), S. 23-28 
    Details
    ISSN: 1618-2650
    Keywords: Best. von Uran ; Aktivierungsanalyse, Neutronen ; 106 KeV-γ-Strahlung von Np-239, Einfluß Seltener Erden
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary The interfering effect of the γ-radiation of radioactive isotopes of the rare earths on the non-destructive neutron activation analysis of μg amounts of uranium, using the 106 KeV-γ-line of 239Np and NaI (Tl). detector, is estimated. The errors introduced by the interfering isotope in the analysis of uranium, are determined as a function of the ratio of the concentration in the sample of the interfering element and uranium. In addition, the possibilities of determining the quantitative effect of these elements are described. The use of the proposed method is demonstrated by the analysis of some geological samples.
    Notes: Zusammenfassung Es wird die Störung bestimmt, die die γ-Strahlung der radioaktiven Isotope Seltener Erden bei der zerstörungsfreien Neutronenaktivierungsanalyse von Mikrogramm-Mengen Uran über die 106 KeV-γ-Linie des 239Np mit Hilfe eines NaJ(Tl)-Detektors hervorrufen kann. Die Fehler in der Analyse von Uran, die das Störisotop verursachen kann, werden als Funktion des Verhältnisses der Konzentration des Störelements zu der des Urans in der Probe bestimmt. Es werden Möglichkeiten beschrieben, den Einfluß störender Elemente quantitativ zu erfassen. Die Brauchbarkeit der vorgeschlagenen Methode wurde durch Analyse einiger geologischer Objekte bewiesen.
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    URL: http://dx.doi.org/10.1007/BF00424160
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    Bestimmung von Platin in borhaltigen Gläsern mit Hilfe der Neutronenaktivierungsanalyse (1973)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 267 (1973), S. 122-126 
    Details
    ISSN: 1618-2650
    Keywords: Best. von Platin in Glas ; Aktivierungsanalyse, Neutronen ; Erfassung bis 0,1 ppm
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Aktivierungsanalyse ist die einzige Methode, mit der Platinmengen im Konzentrationsbereich unter 1 ppm erfaßt werden können. Wegen der hohen Aktivität der Matrix erfolgte die Bestimmung über 199Au, das Tochterprodukt des 31 min 199Pt, das mit seiner Halbwertszeit von 3,15 d ausreichend Zeit für eine chemische Abtrennung bietet. Ein Verfahren, das mit tragbarem Zeitaufwand den Aufschluß des Glases und die Abtrennung des Goldes ermöglicht, wurde ausgearbeitet. Da die hohen Borgehalte vieler Gläser eine starke Neutronenselbstabschirmung bedingen, wurde der Einfluß der Selbstabschirmung in Abhängigkeit von Matrix und Borgehalt sowie die Möglichkeit zu ihrer Verminderung untersucht. — Nach dem beschriebenen Verfahren konnten Platingehalte bis zu 0,1 ppm erfaßt werden.
    Notes: Abstract Neutron activation analysis is the only analytical method allowing the determination of platinum in the concentration range below 1 ppm. Because of the high activity of the matrix the determination was done via the daughter product of 31 min 199Pt, 199Au which due to its half-life of 3.15 d can be chemically separated. A procedure for acid decomposition of the glass and chemical separation of the gold was worked out, which can be performed within a reasonable time. As the boron content of many glasses causes a high neutron self-shielding, the self-shielding effect as a function of the matrix and the boron concentration was investigated. A procedure to reduce the self-shielding effect was also developed. Using the procedure described platinum concentrations down to 0.1 ppm could be determined.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00429965
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  • 32
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    Spurenelementbestimmung in Luftstaubproben mittels Neutronenaktivierung (1973)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 267 (1973), S. 257-260 
    Details
    ISSN: 1618-2650
    Keywords: Best. von Elementen in Luft ; Aktivierungsanalyse, Neutronen ; Spurenanalyse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Neutronenaktivierungsanalyse kann zur Bestimmung von Spurenelementen in Luftstaubproben auch bei Sammelzeiten von nur wenigen Stunden vorteilhaft eingesetzt werden. Für die Sammeltechnik haben sich Cellulose-Papierfilter als besonders spurenarm erwiesen. Für die meisten Elemente sind die Abscheidegrade befriedigend. In einer Reaktor-Kurzzeitbestrahlung von ca. 1 min können die Elemente Se, V, Al, Mg, Br, Cl, In, Mn, in einer nachgeschalteten Langzeitbestrahlung von ca. 1 Tag die Elemente Na, K, Cu, As, W, La, Cd, Au, Sb, Sm, Ca, Fe, Co, Zn, Cr, Sc quantitativ analysiert werden. Im Kernforschungszentrum Karlsruhe und an der Autobahn Karlsruhe—Bruchsal wurden Luftstaubkonzentrationen für die Elemente Se, V, Br, Mn, Cu, As, Zn, Fe, Co ermittelt. Erhöhte Werte an der Autobahn wurden lediglich für Brom gefunden. Blei, mit Atomabsorption bestimmt, verhält sich analog wie Brom.
    Notes: Abstract Neutron activation analysis can be applied to the determination of trace elements in airborn dust samples with great advantage, even if the collection time is only a few hours. Cellulose paper filters for collection have proved to contain a particularly small amount of trace elements. Filter efficiencies are satisfactory for most elements. In a short-time irradiation of approximately 1 min in a reactor the elements Se, V, Al, Mg, Br, Cl, In, Mn can be analyzed quantitatively; in a subsequent long-time irradiation of approximately 1 day, Na, K, Cu, As, W, La, Cd, Au, Sb, Sm, Ca, Fe, Co, Zn, Cr, Sc can be analyzed quantitatively. Airborne dust concentrations for the elements Se, V, Br, Mn, Cu, As, Zn, Fe, Co were determined at the Karlsruhe Nuclear Research Center and close to the motorway between Karlsruhe and Bruchsal. Increased values close to the motorway were encountered only for bromine. Lead as determined by atomic absorption behaves like bromine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425297
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  • 33
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    Electronic Resource
    Spurenelementbestimmung in verschiedenen natürlichen Wasserproben mittels Neutronen-Aktivierungsanalyse (1973)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 267 (1973), S. 270-273 
    Details
    ISSN: 1618-2650
    Keywords: Best. von Antimon, Arsen, Cadmium, Kupfer, Quecksilber, Zink in Wasser ; Aktivierungsanalyse, Neutronen ; Spurenanalyse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Als Ziel der vorliegenden Untersuchung war festzustellen, ob die Neutronen-Aktivierungs-analyse als Methode für eine routinemäßige Überwachung von Trinkwasserproben geeignet ist. Untersucht wurden Wasserproben von Wasserwerken des Gebietes Südbaden auf den Gehalt der Elemente As, Cd, Cu, Hg, Sb und Zn. Die Wasserproben wurden vor der Bestrahlung gefriergetrocknet. Mit Ausnahme des Cu, bei dem das die Messung störende Na durch einfache chemische Trennung entfernt wurde, konnten die Proben direkt nach der Bestrahlung gemessen werden. Die erhaltenen Ergebnisse werden mit den Richtlinien der WHO verglichen. In 2 Fällen wurden diese Konzentrationen erheblich überschritten. Eine Aufstellung der aufgetretenen Kosten wird vorgenommen.
    Notes: Abstract The aim of the presented paper is to determine the capability of neutron activation analysis as a routine control of drinking water. Water samples of waterworks in an area of Southern Germany have been analysed in respect to the content of As, Cd, Cu, Hg, Sb und Zn. The samples were freeze-dried before irradition. The disturbing Na-24 content has been removed by ion-exchange in the case of Cu, while the other elements have been measured directly. The results are compared with the tentative limits for drinking water suggested by the WHO. The corresponding element concentrations exceeded in two cases significantly these limits. The cost of water analysis by neutron activation is calculated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425300
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