Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1970-1974  (4)
  • 1
    Electronic Resource
    Electronic Resource
    Fine structural study on the origin and development of the sphincter pupillae muscle in the West Coast newt (Taricha torosa) (1971)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 170 (1971), S. 57-74 
    Details
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The origin and development of the sphincter pupillae muscle was studied in Taricha torosa by electron microscopy. The larval optic cup with its inner and outer epithelial layers is completely enshrouded by a primary basal lamina. The epithelium can be divided into E and R regions, according to the types of distributed pigment granules, ellipsoidal (E) and round (R). The E region includes the outer layer except the pupillary zone; the R region the inner layer and pupillary zone. The boundary dividing these regions is distinct enough to be called the E-R boundary. Clusters of fine filaments develop in the pigment-containing R cells adjacent to the E-R boundary during metamorphosis. Such R cells subsequently increase their population to form abundle swelling into the anterior ocular chamber. This bundle formation is accompanied by acquisition of a nerve supply from the iridial stroma, and the emergence of collagen fibers as well as secondary basal (or external) laminae surrounding each cell of the bundle. The adult muscle cells retain numerous round pigment granules, desmosomes, and intermediate junction.These facts support the neuroectodermal origin of this sphincter pupillae muscle.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1091700105
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Frog pineal photoreceptor renewal: Preliminary observations (1971)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 171 (1971), S. 99-115 
    Details
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The intracranial epiphysis of the adult frog, Rana pipiens, has been examined by electron microscopic cytochemistry and radioautography. Acid phosphatase is localized within vacuoles of macrophages free in the lumen, in subspherical vesicles of the ellipsoid portions of photoreceptive cell inner segments, and in occasional heterogeneous cytoplasmic inclusions of the supportive cells.The distribution of radioactivity in the epiphysis at intervals of 1, 3, 5, 9, 14, 25, and 60 days following injection of tritiated leucine, as determined by quantitative radioautography, is consistent with an hypothesized process of continual renewal of photoreceptive cell outer segments. The pattern of radioautographic labeling of the pineal photoreceptors, which resembles more closely that of retinal cones than rods, is correlated with previous morphologic and electrophysiological studies of these cells.The radioautographic and cytochemical data suggest that macrophages within the epiphyseal lumen are involved in phagocytosis and, ultimately, in digestion of degenerate outer segments. They may perform a function similar to that of pigment epithelial cells of the lateral eye retina.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1091710107
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Filamentous and matrix components of skeletal muscle Z-disks (1972)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 172 (1972), S. 623-642 
    Details
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The fine structural appearance of Z-disk lattices in vertebrate skeletal “fast” muscle varies depending upon whether osmium or glutaraldehyde has been employed as the primary fixative. Prior investigators have attributed the differences to change in the extent of actin filament overlap within the Z-disk and/or to rearrangement of Z-disk filaments.Adult frog and young newt “fast” muscle has been studied under various degrees of stretch, with several different aldehyde and osmium fixation procedures, and after plastic section digestion techniques utilizing Pronase or pepsin. Serial cross sections of Z-disks were correlated with oriented cross and longitudinal sections. Fixation with collidine-buffered osmium and veronal acetate-buffered glutaraldehyde seems to provide the greatest and most distinctly contrasting differences. A consistently arranged phase, the filamentous lattice, can be discerned after either fixation. However, a second phase, termed “Z-disk matrix,” appears variable, perhaps due to extraction during primary osmium fixation procedures. Glutaraldehyde-fixed frog muscle Z-disks display a copious matrix, one which is seldom totally depleted by osmium fixation. In young newt muscle Z-disks, little matrix is present after glutaraldehyde fixation and none of it remains after primary osmium. In Z-disks fixed by either method, matrix that is retained appears to be deposited in lattice-like patterns. It is suggested that these matrix patterns, or their loss, are the basis for the varying images of Z-disks observed under diferent fixation conditions and that the filamentous lattice is relatively stable. The Z-disk is more rapidly obliterated by Pronase or pepsin digestion than is any other muscle component, including actin (which appears notably unreactive). The rapid digestion effect is limited to the region postulated to include the matrix phase. Models for the structural interrelationship of filamentous and matrix phases are discussed and compared to prior Z-disk models.
    Additional Material: 17 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1091720403
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Development of the amphibian pineal organ; Fine structure during maturationThis study was supported by research grant GB 14098 from the National Science Foundation and GM 16598 from the United States Public Health Service. The authors are indebted to Mrs. Sandra Kunz and Mrs. Nancy Gross for their able technical assistance and to Mrs. Doris Ringer for secretarial help. (1971)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 170 (1971), S. 129-142 
    Details
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The pineal organ of the West Coast newt Taricha torosa has been examined electron microscopically one, two and five years after metamorphosis. Although the organ has flattened with concomitant reduction of the lumen, the basic larval organization of the pineal photoreceptors and supportive cells is retained. Photoreceptors demonstrate both basal synaptic regions and outer segments, although the latter are disorganized as compared to the larva. Supportive cells, which increase in volume with age, contain membranous debris suggesting a sequence of phagocytosis of outer segments. Tubular vesticular membrane complexes enclosing 450 Å tubules are found in supportive cell processes adjacent to the basal lamina near blood vessels. Despite these changes the adult pineal organ retains the morphological entities thought to be necessary for photoreceptive function.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1091700202
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...