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  • Light and electron microscopy  (47)
  • Springer  (47)
  • 1970-1974  (47)
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  • Springer  (47)
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  • 1
    Electronic Resource
    Electronic Resource
    Light- and electron-microscopic studies of the pancreatic islet cells in the chicken under normal and experimental conditions (1971)
    Springer
    Cell & tissue research 116 (1971), S. 205-227 
    Details
    ISSN: 1432-0878
    Keywords: Chicken pancreas ; Pancreatic islet cells ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Light- and electron-microscopic observations were made on the alpha, beta and delta cells of the pancreatic islets of the domestic fowl and on their cytologic changes following the administration of glucose, glucagon, insulin, alloxan and carbutamide. 1. Under the light and electron microscope, two types of islets are recognized: (1) the “alpha” islet composed of alpha and delta cells and (2) the “beta” islet made up of beta and delta cells. 2. Alpha cells are large, round or columnar in shape, and contain less-developed cellular organelles and characteristic alpha granules. These dense, spherical granules are surrounded by a single smooth membrane and the matrix, with high magnification, exhibits a glomerular structure. 3. Beta cells are round, oval, or irregular in shape, and contain more or less developed cellular organelles and characteristic beta granules. These granules are polymorphic and consist of three main types; needle or bar-shaped, spherical, and ring-shaped; they are enclosed by a smooth membrane. 4. Delta cells are characterized by the presence of less dense spherical granules (diameter about 500 mμ) that are partially surrounded by an indistinct membrane. They are considered to be an independent type of cell of unknown function. 5. “Acinar-islet cells” with intermediate endocrine and exocrine morphology, are observed between the endocrine and exocrine cells along the periphery of the islets. The presence of occasional fragments of plasma membrane suggests that the cytoplasm of acinar and islet cells may intermingle. 6. The alpha cells exhibit margination of granules and release of granules by emiocytosis, in hypoglycemia induced by the administration of insulin or carbutamide. 7. After administration of glucose, glucagon or carbutamide, beta cells exhibit vacuolation and release of granules by intracytoplasmic dissolution of the specific needle- or bar-shaped granules followed by diacrine passage through the plasma membrane. On the other hand, after the administration of glucose, glucagon or carbutamide, Gomori-positive, dense, small-cored granules occur in the periphery of cytoplasm along the capillary with indications of release by emiocytosis. 8. Delta cells increase remarkably and extrude granules by emiocytosis, after the administration of glucagon, alloxan or carbutamide. 9. Administration of carbutamide stimulates the secretory activity of beta cells, as indicated by the diacrine feature of specific beta granules and the emiocytosis of small-cored granules. Carbutamide also causes an increase of immature non-granular cells in the alpha and beta islets.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00331262
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  • 2
    Electronic Resource
    Electronic Resource
    Paraganglienzellen im Ganglion cervicale uteri der Maus (1972)
    Springer
    Cell & tissue research 130 (1972), S. 249-261 
    Details
    ISSN: 1432-0878
    Keywords: Chromaffin tissue ; Ganglion cervicale uteri ; Mouse ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das chromaffine Gewebe im Ganglion cervicale uteri der Maus wurde licht- und elektronenmikroskopisch in verschiedenen Funktionsstadien des Genitale untersucht. Die Befunde decken sich weitgehend mit den bisher bekannten Beobachtungen an extraadrenalem, chromaffinem Gewebe anderer Lokalisation. 1. Das chromaffine Gewebe besteht aus granulahaltigen Paraganglienzellen und Hüllzellen, die Schwannschen Zellen gleichen. 2. Die Granula der Paraganglienzellen sind sehr kontrastreich und von einer Membran umhüllt, die größeren Abstand von ihrem dichten Inhalt haben kann. 3. Gelegentlich sind die Paraganglienzellen mit Zilien ausgestattet. 4. Zellen mit wenig Granula haben ein kräftiger ausgebildetes rauhes endoplasmatisches Retikulum als Zellen mit hohem Granulagehalt. 5. Die paraganglionären Zellen haben keine besondere Beziehung zum Gefäßsystem. 6. Die Paraganglienzellen stehen mit Nervenendingungen durch Synapsen in Kontakt, die sowohl überwiegend synaptische Bläschen als auch überwiegend „dense core vesicles” enthalten können. Sie scheinen also sowohl durch cholinerge als auch durch adrenerge Innervation kontrolliert zu werden. 7. Unterschiede in der Ultrastruktur der Paraganglienzellen konnten nur zwischen ausgewachsenen und infantilen Tieren festgestellt werden. Letztere haben einen höheren Anteil an Zellen mit wenig Granula. 8. Die Befunde scheinen für eine lokale endokrine Beeinflussung der Nervenzellen des Ganglion cervicale uteri durch Abgabe von Katecholaminen aus den Paraganglienzellen zu sprechen.
    Notes: Summary The chromaffin tissue in the ganglion cervicale uteri of mice was investigated in different functional stages of their reproductive system by light and electron microscopy. The observations correspond to the findings obtained in extra-adrenal chromaffin tissue localized in other regions. 1. The chromaffin tissue consists of granule containing paraganglionic cells and of surrounding cells that resemble Schwann cells. 2. Occasionally the paraganglionic cells possess cilia. 3. The granules in the cytoplasm of paraganglionic cells are very electron dense and are enveloped by a membrane that forms a vesicle with a diameter either corresponding to that of the granule or considerably larger than the latter. 4. Cells with little granules have a better developed rough endoplasmic reticulum than cells with a great number of granules. 5. The paraganglionic cells have no special relationships to blood vessels. 6. The paraganglionic cells are innervated by synapses that possess synaptic vesicles and by synapses that show accumulations of dense core vesicles. The paraganglionic cells seem to be under the control of cholinergic and adrenergic innervation. 7. Differences of ultrastructure of the paraganglionic cells were seen only between adult and infantile animals. The latter have a greater number of cells containing only a small quantity of granules. 8. The findings suggest the hypothesis of a local endocrine influence of the paraganglionic cells on the neurons of the ganglion cervicale uteri by release of catecholamines.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00306961
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  • 3
    Electronic Resource
    Electronic Resource
    Licht- und elektronenmikroskopische Befunde zur Struktur der Bowmanschen Drüsen im Riechepithel der weißen Maus (1972)
    Springer
    Cell & tissue research 131 (1972), S. 329-346 
    Details
    ISSN: 1432-0878
    Keywords: Olfactory mucosa ; Mouse ; Glands of Bowman ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das erste Auftreten der Glandulae olfactoriae in der olfaktorischen Region der Maus wird beschrieben. Die Struktur der Bowmanschen Drüse und ihre topologische Beziehung zu den übrigen zellulären Elementen im Riechepithel wird untersucht. Die Bedeutung des Sekrets für die Bildung des Deckhäutchens wird diskutiert. Die Bowmanschen Drüsen der Maus erreichen im letzten Viertel des intrauterinen Lebens die Lamina propria des Riechepithels. In den Endstücken finden sich dunkle, sekretreiche und helle, sekretarme Zellen. Die sezernierenden Zellen der Bowmanschen Drüsen sind nicht auf die Lamina propria beschränkt, sondern erstrecken sich bis in die untersten Anteile des Kernlagers im Riechepithel. Beim Austritt der Bowmanschen Drüsen aus dem Riechepithel in die Lamina propria konfluieren die Basalmembranen dieser Gewebeanteile miteinander. Die gemeinsame Basalmembran kann sich noch eine Strecke weit bis in den normalen Interzellularraum zwischen Drüsen- und Riechepithelanteilen einsenken. In den apikalen Anteilen des Riechepithels wird der Ausführungsgang von den benachbarten Sinnes- und Stützzellen nur durch eine normal breite Interzellularfuge getrennt. Im Ausführungsgang der Bowmanschen Drüse finden sich dunkle und helle auskleidende Zellen. Die durch Desmosomen miteinander verbundenen Epithelzellen der Ausführungsgänge zeigen Zeichen einer Sekretion. Die periphersten Ausläufer des Ausführungsgangepithels erstrecken sich lediglich bis in das Terminalplattenniveau der Stützzellen, mit denen sie sich durch desmosomenartige Kontaktzonen verbinden. In der Verlängerung der Ausführungsgänge wird das Lumen peripher des Terminalplattenniveaus von den apikalen Stützzellanteilen und deren Mikrovilli sowie von den obersten Anteilen der Dendriten, von den Riechköpfen und den Sinneshaaren der Rezeptorzellen umgrenzt. Im Lumen der Ausführungsgangverlängerung finden sich im Bereich des olfaktorischen Saumes flächenhafte Ansammlungen von Sekret. Das Sekret im intervillösen Raum des olfaktorischen Saumes zeigt eine besondere Affinität zu den Membranen der peripheren Sinneszellausläufer. In der intrauterinen Lebensphase ließ sich bisher kein Deckhäutchen feststellen. Die austrocknende Wirkung der Luft auf das Sekret der Bowmanschen Drüsen wird als Entstehungsmechanismus für das Deckhäutchen in Erwägung gezogen.
    Notes: Summary First appearance, structure and topological relations of Bowmans' glands in the regio olfactoria of white mice are described. The importance of these glands for the formation of the terminal mucous cover of the olfactory epithelium is discussed. In the last quarter of intrauterine life the glands of Bowman reach the lamina propria. In the terminal portion of the glands dark cells with many secretory droplets and pale cells with only a few of them can be seen. Secretory active cells are localized in the basal part of the olfactory epithelium as well. When entering the lamina propria the irregular wide basement membrane of the glands joins that one of the epithelium. It is possible to follow up this joined basement membrane for a short distance between the glands and the cells of the olfactory epithelium. Peripheral to the very basal part of the olfactory epithelium there is no basement membrane around the glands' tissue. Receptors and sustentacular cells are separated from the gland only by a normal intercellular space. The epithelium of the ducts consists of dark and light cells as well. They are connected with the sustentacular cells by desmosomelike contacts. In its prolongation the lumen of Bowman's duct is lined by the apical portions of the sustentacular cells and their microvilli, and by dendrites, olfactory vesicles, and sensory cilia of the receptor cells. In the region of cilia and microvilli one can see masses of secretion which have confluenced. In the intervillous space its special affinity to the receptor's membranes is evident. During the intrauterine phase of life no terminal mucous cover could be demonstrated. The drying effect of the air as a possible reason for the origin of the terminal mucous cover is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00582855
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  • 4
    Electronic Resource
    Electronic Resource
    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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  • 5
    Electronic Resource
    Electronic Resource
    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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  • 6
    Electronic Resource
    Electronic Resource
    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.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00306758
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  • 7
    Electronic Resource
    Electronic Resource
    The fine structure of somatic muscles of tardigrada (1974)
    Springer
    Cell & tissue research 149 (1974), S. 81-89 
    Details
    ISSN: 1432-0878
    Keywords: Muscle cells ; Tardigrada ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The somatic muscles of the tardigrades Macrobiotus hufelandi and Milnesium tardigradum consist of elongated cells which are structurally independent of each other and insert in the body wall. The contractile part of the muscle cells contains thick and thin myofilaments. The thin filaments run together in typical dense bodies. In relaxed muscles clear A-, I- and H-zones are formed, and the dense bodies are often accumulated in groups. In ribbon like I-zones they are sometimes arranged side by side in rows and resemble fragmented Z-rods. The sarcoplasmic reticulum is localized primarily in the small region between the contractile apparatus and sarcolemma, and is represented by a system of smooth, flat, reticulated cisternae. The contractile apparatus of the somatic muscles is compared to that of smooth and obliquely striated muscles of several invertebrates. On the basis of certain distinguishing features of the contractile part of somatic muscles of tardigrades, it is suggested that these muscles should be referred to as a type intermediate between smooth and obliquely striated muscles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00209051
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  • 8
    Electronic Resource
    Electronic Resource
    Homing of lymphoid cells in the developing palatine tonsil of the rabbit (1972)
    Springer
    Cell & tissue research 134 (1972), S. 65-84 
    Details
    ISSN: 1432-0878
    Keywords: Tonsil (rabbit) ; Lymphoid cell homing ; Tonsil culture ; Thymus culture ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ‘homing’ process of lymphoid cells in the developing palatine tonsil of the rabbit was investigated by culturing isolated embryonic tonsils in diffusion chambers on the chick chorioallantoic membrane. An analysis of the origin and fate of lymphoid cells in cultured tonsils from subsequent stages of development strongly supported the existence of the ‘homing’ mechanism for lymphoid cells, postulated on morphological data. From the 19th day of gestation there is an influx of motile lymphoid (stem) cells into the tonsillar primordium, reaching a peak between the 22nd and 24th day. Of these cells a large proportion is immobilized by mesenchymal cells and becomes sessile lymphoid cells which remain firmly attached to mesenchymal cells during culture. After the 24th day practically all sessile lymphoid cells lose their contact with the mesenchymal cells and migrate to the bottom of the diffusion chamber. This different behaviour of sessile lymphoid cells in cultured tonsils of later developmental stages may imply a functional differentiation of these cells. By comparing the fate of morphologically differentiated lymphoid cells in cultured palatine tonsils and thymus of rabbit embryos, the different nature of tonsil and thymus lymphocytes could be demonstrated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307235
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  • 9
    Electronic Resource
    Electronic Resource
    Faseranalytische Untersuchungen an peripheren Nerven bei Tieren verschiedener Größe (1971)
    Springer
    Cell & tissue research 119 (1971), S. 99-114 
    Details
    ISSN: 1432-0878
    Keywords: Peripheral nerve ; Body size ; Axon diameter/Fibre diameter ; Internodal length ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Nn. ischiadici von Maus, Ratte, Meerschweinchen, Hund und Katze wurden licht- und elektronenmikroskopisch faseranalytisch untersucht (Methodik s. G. Schnepp u.a., 1971). Dem Vergleich diente der N. phrenicus des Hundes. 1. Für den Quotienten „g” (=mittlerer Axondurchmesser/Fasergesamtdurchmesser) ergibt sich am lichtmikroskopischen Material ein stetiger Anstieg von 0,4 für dünne Fasern bis zu 0,6 für die dicksten Fasern. Bei gleichem Gesamtdurchmesser haben Ratten und Hunde die stärksten, Mäuse dagegen die dünnsten Markscheiden. 2. Die elektronenmikroskopisch ermittelten Werte des Quotienten „g” weichen von den lichtmikroskopischen ab. Bei den ersteren ergibt sich eine weitgehende Konstanz um 0,6. Diese Werte entsprechen den von Rushton (1951) aus theoretischen Gründen geforderten. Auch im elektronenmikroskopischen Material haben die Nervenfasern der Ratte die stärksten Markscheiden. 3. Eine lineare Proportionalität zwischen der Internodallänge einer Tierart und dem steigenden Faserdurchmesser wird bestätigt. In jedem N. ischiadicus kommen vereinzelte Fasern mit Internodalabständen von etwa 300 μ vor, unabhängig vom Faserkaliber. 4. Im elektronenmikroskopischen Bild sind keine artspezifischen Unterschiede in der Struktur und Verteilung der marklosen Nervenfasern zu beobachten.
    Notes: Summary The sciatic nerves were analysed using light and electron microscopes in the mouse, rat, guinea pig, cat, and dog (see Methods of G. Schnepp et al., 1971). 1. In light microscopic material, the ratio “g” between mean axon diameter and mean fibre diameter increased from 0.4 for small fibres to 0.6 for the thick fibres. For a given fibre diameter the myelin sheaths in rats and dogs were the thickest, while those in mice were the thinnest. 2. The ratio “g” in electron micrographs on the other hand was constant at 0.6 over a wide range of fibre diameters. The ultrastructural values agreed with those postulated by Rushton (1951) for optimal nerve conduction. In the electron microscopic material, the myelin sheaths were the thickest in the rat. 3. A linear proportionality was confirmed to exist between internodal length and increasing fibre size. Independently of fibre size, in all sciatic nerves, a few fibres were found with internodal length of about 300 μ. 4. In electron micrographs, no species differences were observed in the structure or distribution of unmyelinated nerve fibres.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00330541
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  • 10
    Electronic Resource
    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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