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  • 1
    ISSN: 1520-4995
    Quelle: ACS Legacy Archives
    Thema: Biologie , Chemie und Pharmazie
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 109 (1963), S. 0 
    ISSN: 1749-6632
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Allgemeine Naturwissenschaft
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Journal of Morphology 128 (1969), S. 67-93 
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The endoskeletal structure supporting the gill-books of Limulus polyphemus has been investigated by means of light and electron microscopy, chemical analysis and x-ray diffraction. This tissue is a cartilage which has significant correspondences with both vertebrate cartilage and plant tissues. Morphologically, the Limulus cartilage resembles certain cellular vertebrate cartilages with relatively scant matrix, and also certain plant parenchyme, collenchyme and sclerenchyme tissues. Of particular interest, was the observation that during cytoplasmic division, a phragmasome-like structure appears between the daughter cells of the dividing gill cartilage cells. This phragmasome-like structure appears to be a precursor of new matrix (cell-wall) formation between the young chondrocytes, in much the same fashion as its counterpart in plant tissues. Perichondrial cells and underlying chondrocytes contain lipid droplets, abundant glycogen and ribosomes, as do corresponding vertebrate cartilage cells. In some of the Limulus cells, glycogen and ribosomes appear to be admixed with lipid, forming aggregates in which all three materials are in intimate intraparticulate relationship. During molting, the number of ribosomes seen in chondrocytes increases. The tissue contains both hydroxyproline and hydroxylysine, and gives a weak x-ray diffraction pattern.
    Zusätzliches Material: 28 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 56 (1963), S. 355-361 
    ISSN: 1615-6102
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary White pine and Rhododendron leaf chloroplasts were observed with the electron microscope in late as well as in mid-winter. It was clear that even in late winter there was no indication of chloroplast “disintegration,” fractionation, or retrogression. Intergrana lamellae often showed close approximation as in grana lamellae, a situation now apparently considered normal. A slight space was observed between closely appressed grana lamellae where two “thylakoids” approached one another. This is also apparently normal in functioning chloroplasts. Vesicles were sometimes seen in pine chloroplasts, suggesting chloroplast disintegration, but this was only rarely seen, and seems to be atypical. Invagination of the inner layer of the chloroplast envelope in winter chloroplasts suggested, however, they were still in a developing stage. Fixation and embedding was much more successful in winter than in summer. Summer fixation and embedding was improved by the addition of 1 % sucrose to the KMnO4.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 215 (1986), S. 407-412 
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: Axoglial contacts were observed in an ultrastructural study of the area postrema of the cat. According to the disposition of the electron-dense projections attached to the adjoining membranes these contacts were classified as symmetrical or asymmetrical. The axon profiles contained aggregations of clear vesicles randomly distributed or grouped in clusters adjacent to the electron-dense projections. Dense core vesicles were occasionally seen. The neuroglial profiles were either astrocytic or ependymoglial in nature. The astrocytes showed a clear cytoplasm, polymorphous vesicles, mitochondria, glycogen granules, and bundles of filaments. The ependymal cells, in contrast, had a more electron-dense and granular appearance, tubular structures, irregular vesicular formations, profiles of smooth reticuloendoplasm, and filaments grouped in bundles or isolated in the cytoplasm. The possibility that these contacts might play a role in the chemical transfer from neurons to glial cells is discussed on the basis of existing biochemical data.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 53 (1961), S. 575-583 
    ISSN: 1615-6102
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary 1. When leaf and bark tissues ofPinus strobus were fixed in osmium, embedded in methacrylate, and sectioned, winter-type chloroplasts appeared as distinct, intact entities under the electron microscope, although often closely appressed to one another in the folds or sides of the cells. 2. Grana and lamellae were clearly visible in winter as well as in summer; the principal change from summer to winter appeared to be the loss of starch and perhaps also “fat droplets”. 3. The larger size of the summer chloroplasts is apparently the result of starch grain growth, but may also be caused by partial vacuolization of chloroplasts in summer. Permanganate-fixed bark cells contained unvacuolated chloroplasts in summer. 4. In winter, a network or reticulmn occurred in all living cells, apparently emeshing mitochondria as well as chloroplasts, and in sieve cells extending through the plates. In summer, this reticulum appeared to be less extensive than in winter.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 57 (1963), S. 628-635 
    ISSN: 1615-6102
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary 1. Fixation in osmium, dehydration, and embedding of frond cells ofFucus vesiculosus L. proved to be more successful in winter than in summer, possibly because of biochemical changes in the cytoplasm or changes in permeability with the season. 2. There was no apparent change in the ultra-structure of chromoplasts from summer to winter. Six different lamellae, formerly believed to be four, were observable in a packet, and about 13 such packets across the thick part of the chromoplast. Globuli in chromoplasts appeared to consist of two membranes and have optically empty centers. 3. Cytoplasmic vacuoles appeared nearly filled in winter with an electron-dense material, while in summer, vacuoles were not so-filled, and some of the summer vacuoles appeared smaller than in winter.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 8
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Journal of Morphology 131 (1970), S. 417-430 
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: In both light and electron microscopes, head cartilage from the squid Loligo pealii strongly resembles vertebrate hyaline cartilage. The tissue is characterized by the presence of irregularly-shaped cells suspended in an abundant matrix. Cell and matrix contents stain metachromatically with cationic dyes such as toluidin blue. Each cell gives off extensions which ramify via a network of channels throughout the matrix. Thereby, a system of inter-connecting canaliculi is established, with many similarities to the intercanalicular systems seen in vertebrate bone and cartilage tissues. In the electron microscope, the squid cartilage cells are seen to have very abundant endoplasmic reticulum and Golgi complex material. Mitochondrial transformations involving loss of cristae, the appearance of filaments in the mitochondrial matrix, and figures suggesting budding, also occur. Nuclear pores are numerous and easily detected. The matrix is characterized by the presence of a system of decussating fibrils which form polygonal figures, with granules usually evident at the points of intersection of fibrils. By chemical analysis the tissue contains 3- and 4-hydroxyproline and hydroxylysine. Preliminary wide single x-ray diffractions show a pattern characteristic for unoriented collagens, with 12 Å (intermolecular) and 2.86 Å (helix) reflections.
    Zusätzliches Material: 15 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 9
    ISSN: 0095-9898
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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