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  • 1
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 2 (1982), S. 93-101 
    ISSN: 0886-1544
    Schlagwort(e): cell motility ; singlet microtubules ; dynein ; coccid insect ; aflagellate spermatozoa ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: In this report we demonstrate that in the coccid insects Pseudococcus, Phenacoccus, and Planococcus the whole spermatozoon is made up by a nuclear central core surrounded by two complete and one incomplete turns of concentric microtubule palisades. Microtubules of the outer row are linked by a system of short projections 6 nm long; those of the inner row are linked to each other by similar arms; a second system of 6 nm arms links the tubules of each inner row to those of the respective outer row. All these systems of arms are longitudinally spaced every ∼ 12 nm. The motility of this spermatozoon is due to waves progressing from the posterior extremity to the anterior one. By SDS polyacrylamide gel electrophoresis a group of high molecular weight polypeptides is detected, one of which migrates in coincidence with the A dynein band from sea urchin sperm. Our data suggest that occurrence in coccid spermatozoon of a motility due to singlet tubules-dynein interaction.
    Zusätzliches Material: 11 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Gamete Research 10 (1984), S. 373-396 
    ISSN: 0148-7280
    Schlagwort(e): fish spermatozoa ; comparative spermatology ; Cyprinidae ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie
    Notizen: The spermatozoa of seven fishes belonging to Cyprinid family are examined. They have no acrosome, like all Teleost fishes, a spheroidal or slightly elliptic nucleus, always eccentrically placed on the tail, two variously oriented centrioles, and a postnuclear cytoplasmic region of various size that contains some mitochondria (2 to 10) and surrounds a periaxonemal postnuclear canal. The tail is of moderate length (from 36 to 60 μm) and contains a “9 + 2” axoneme: both dynein arms are present. Comparative examination of the spermatozoa in the seven species shows that significant differences occur among them, even when they belong to the same genus. These concern the tail length; the position of the centrioles, the proximal with respect to the central one and with respect to the nucleus; the number of mitochondria, which is in relationship to the depth of the postnuclear canal. In the uniform general pattern of the ultrastructure of the Cyprinid spermatozoa, each species is characterized by a particular organization of the sperm organelles; in this respect, the two species examined by us, Leuciscus cephalus and souffia, are more closely related, even if easily recognizable one from the other. From a phylogenetic point of view, the comparative spermatology of the Cyprinid fishes suggests that the mitochondrial number is a good character, which enables us to order them in a phylogenetic arrangement.
    Zusätzliches Material: 40 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Gamete Research 22 (1989), S. 249-255 
    ISSN: 0148-7280
    Schlagwort(e): human spermatozoa ; “crater defect,” ; nuclear malformation ; acrosome malformation ; cytoskeleton ; sperm head morphogenesis ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie
    Notizen: This report describes the “crater defect” in human spermatozoa, a malformation that consists of a nuclear and acrosomal invagination present in 100% of the cells, whereas tail structure and motility are fairly normal. The defect occurs during spermiogenesis. A possible concomitance with abnormalities in the microtubular apparatus involved in the sperm molding is discussed.
    Zusätzliches Material: 10 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Gamete Research 16 (1987), S. 11-21 
    ISSN: 0148-7280
    Schlagwort(e): epididymal spermatozoa ; acrosomal molding ; SH and S-S-groups ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie
    Notizen: The action of gossypol on the acrosomal complex in rats has been investigated by microscopical and submicroscopical methods. The drug displays its morphological action only on spermatozoa during the transit through the epididymis, causing malformations and vesiculations. It appears to exert a primary action on the S—S groups formation, disturbing morphological molding occurring in this period and inhibiting capacitation.
    Zusätzliches Material: 21 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Gamete Research 3 (1980), S. 203-209 
    ISSN: 0148-7280
    Schlagwort(e): actin ; mitochondrial movement ; spermiogenesis ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie
    Notizen: The presence of actin filaments around mitochondria during vertebrate spermiogenesis was demonstrated by immunofluorescence and immuno-electron microscopy and by heavy meromyosin decoration. The presence of actin is supposed to be related to mitochondrial rearrangements occurring in the spermatid stage.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Gamete Research 23 (1989), S. 181-188 
    ISSN: 0148-7280
    Schlagwort(e): human spermatozoa ; male infertility ; decapitated ; decaudated ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie
    Notizen: The “decapitated sperm” defect, found in both of two sterile brothers, may be assumed to have a genetic origin. The present material suggests that the term “decapitated spermatozoa” is not exact, because detached heads and tails were found in the brothers' ejaculate that could be regarded as “decapitated tails” and “decaudated heads.” The present report describes frequent, more or less advanced stages of detachment. Both heads and tails showed a normal structure in which only the postnuclear region was deficient, lacking basal plate and implantation fossa. A break at a different level of the midpiece, and therefore three kinds of separation, were observed. The defect, according to the present research, must originate in the testicular region, whereas the detachment occurs in the epididymis.
    Zusätzliches Material: 16 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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