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
  • 1975-1979  (587)
  • 1975  (587)
  • Cell & Developmental Biology  (476)
  • Electron microscopy  (111)
  • 1
    Electronic Resource
    Electronic Resource
    Ultrastructural study of calcium-containing precipitation in human parathyroid glands (1975)
    Springer
    Virchows Archiv 368 (1975), S. 99-108 
    Details
    ISSN: 1432-2307
    Keywords: Electron microscopy ; Calcium ; Parathyroid glands ; Chief cells ; Oxyphil cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Using the potassium pyroantimonate technique for ultrastructural localization of cations and X-ray elemental analysis with both energy dispersive and wave-length dispersive systems, calcium-containing precipitates were found in normal, hyperplastic and adenomatous human parathyroid glands. Differences were observed between oxyphil cells, and suppressed, stimulated and active chief cells in the content and localization of intracellular precipitation. The oxyphil cells and suppressed chief cells possessed precipitates mainly in nuclei and medium-sized and large mitochondria, whereas the stimulated chief cells possessed precipitates in normal-appearing and morphologically altered mitochondria, and in smooth-surfaced vacuoles and cytosol. The active chief cells usually showed a rather sparse precipitation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00432411
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Déficit en alpha-1-antitrypsine chez l'enfant (1975)
    Springer
    Virchows Archiv 369 (1975), S. 19-27 
    Details
    ISSN: 1432-2307
    Keywords: Alpha-1-antitrypsin deficiency ; Liver ; Electron microscopy ; Endoplasmic reticulum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Fourteen liver biopsies from twelve young patients with liver diseases associated with homozygous, PiZZ phenotype, alpha-1-antitrypsin deficiency in their sera were examined by electron microscopy. In all these biopsies characteristic homogeneous material was found in some hepatocytes and corresponded, when observed on adjacent semithin sections by light microscopy, to the deposit stained by periodic acid Schiff reaction. The accumulation in perinuclear spaces resulted in intranuclear invaginations, but the major deposit was located in lumens of the endoplasmic reticulum. The limiting membranes were rough and smooth but the extent of the latter was so large that only this type of reticulum seemed peculiarly involved in the accumulating process. On the contrary, Golgi complexes did not seen obligatorily involved by this process because, when observed, they appeared almost normal even in heavily overloaded liver cells. At least for the PiZZ phenotype, the abnormal substance would be an asialo form of normal alpha-1-antitrypsin. Thus the subject of this study is the morphologic translation of an impairment in the synthesis of a glycoprotein. In the light of data concerning the synthesis of such proteins our findings lead us to suggest: The ultrastructural patterns observed in alpha-1-antitrypsin deficiency cannot give the expected morphologic evidence of the biochemical data which locate the first binding steps of monosaccharide residues in the rough endoplasmic reticulum. The absence of sialic acid could not result from an enzymatic defect primarily located in Golgi complexes but could be secondary to an impairment in the binding of one monosaccharide residue which improves subsequent fixation of sialic acid, in the smooth endoplasmic reticulum. Finally it seems necessary to emphasize that the relationship between the abnormal substance and various important non specific lesions is largely unknown and that we don't know the significance of polymorphous dense bodies observed in ductular cells during the cholestatic period.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00432458
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Zur Ultrastruktur fibröser und histiocytärer Hauttumoren (Dermatofibrom, Dermatofibrosarcoma protuberans, Fibroxanthom und Histiocytom) (1975)
    Springer
    Virchows Archiv 368 (1975), S. 253-274 
    Details
    ISSN: 1432-2307
    Keywords: Tumors of the skin ; Histogenesis ; Classification ; Labyrinth nuclei ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wird über den Feinbau folgender Hauttumoren berichtet: Dermatofibrom (7 Fälle), Histiozytom (4 Fälle), Dermatofibrosarcoma protuberans (1 Fall) und Fibroxanthom (1 Fall). Aufgrund ihrer unterschiedlichen ultrastrukturellen Merkmale ist eine zweifache Unterteilung dieser Hauttumoren möglich: In eine Tumorgruppe, umfassend das Dermatofibrom, Dermatofibrosarcoma protuberans und Fibroxanthom, bei der die Faserbildung im Vordergrund steht und für deren Histogenese Fibroblasten angenommen werden können. Diese Tumortypen unterscheiden sich vom Histiozytom, dessen Zellcharakter vor allem durch die stark ausgeprägte Phagozytose- und Speichertätigkeit (Fett und Hämosiderin) bestimmt wird und für welches eine histogenetische Ableitung von Histiozyten wahrscheinlich ist. Die Zellkerne des Dermatofibromes und des Histiozytomes weisen einen einfachen Oberflächenverlauf auf, die des Dermatofibrosarcoma protuberans und Fibroxanthomes haben hingegen sehr stark gegliederte Formationen („Labyrinthkerne”). Diese Kernsegmentierung ist für das Dermatofibrosarcoma protuberans ein morphologisches Korrelat seiner Semimalignität. Eine Klassifizierung der faserbildenden Tumoren als „fibröse Histiozytome” erscheint aufgrund der ultrastrukturellen Analyse nicht gerechtfertigt.
    Notes: Summary A report on the ultrastructure of the following skin tumors: dermatofibroma (7 cases), histiocytoma (4 cases), dermatof ibrosarcoma protuberans (1 case), and fibroxanthoma (1 case). Because of their different ultrastructural characteristics a division into two groups is possible: one group of tumors would include dermatofibroma, dermatofibrosarcoma protuberans, and fibroxanthoma, where the formation of fibers is extensive and fibroblasts are suggested for its histogenesis. These types of tumor differ from histiocytoma, the cellular character of which is determined by a very pronounced phagocytosis and storage of lipid and hemosiderin; a histogenesis from histiocytes is probable. The nuclei of dermatofibroma and histiocytoma show a simple surfacedevelopment, whereas the nuclei of dermatofibrosarcoma protuberans and fibroxanthoma show multisegmented nuclei (“labyrinth nuclei”). In the case of dermatofibrosarcoma protuberans this kind of nuclear segmentation seems to be a morphologic correlate of its semimalignancy. Based on ultrastructural analysis a classification of these fiber-producing tumors into “fibrous histiocytomas” is not justified.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00432527
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Late changes of irreversible post-partum renal failure (1975)
    Springer
    Virchows Archiv 367 (1975), S. 171-179 
    Details
    ISSN: 1432-2307
    Keywords: Kidney failure ; Pregnancy ; Electron microscopy ; Hemolytic-uremicsyndrome ; Basement membrane ; Endothelium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The clinico-pathological data from a patient with irreversible post-partum renal failure (IPRF) are presented. The electron microscopy of the late changes are described for the first time and consists of: 1. Thickening of the basement membrane. 2. Interposition of mesangial cells and matrix between the thickened basement membrane and the endothelial cell encircling the periphery of the tuft. 3. Multiplication of basal lamina material between mesangial cells and endothelial cells. 4. Proliferation of endothelial cells. All of the above changes tend to obliterate the glomerular tufts and transform the vascular lumina into slit-like spaces. They explain morphologically why most patients with IPRF terminate in chronic renal failure, if they survive the early changes. The late occurring hypertension is regarded as a secondary stimulation of the renin-angiotension system caused by partial or complete occlusion of arteries and arterioles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00430705
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Ultrastructural localization of plasma lipoproteins in human intracranial arteries (1975)
    Springer
    Virchows Archiv 369 (1975), S. 111-121 
    Details
    ISSN: 1432-2307
    Keywords: Atherosclerosis ; apoB ; LDL ; VLDL ; Immunoperoxidase ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine-structural localization of apoB, the major protein constituent of both the low and very low density plasma lipoprotein fractions, was described in human middle cerebral and basilar arteries. Using an immunoperoxidase technique together with electron microscopy, apoB was localized only in arteries with atherosclerotic involvement and to the following regions in these arteries: 1. on the outer aspects of extracellular spherical structures with diameters of 250 to 700 Å found predominantly in lipid cores and between bands of collagen fibers of advanced atherosclerotic lesions; 2. on the surface of reduplicated elastica; 3. along collagen fibers and; 4. on aggregates of extracellular spherical lipid globules. These results suggest that the extracellular spheres may represent the fine-structural morphology of deposited low and very low density lipoproteius and that free apoB may be bound to lipid globules, elastica, and collagen fibers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00433237
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Differentiation of sympathicoblasts in cultures of chick ganglia (1975)
    Springer
    Anatomy and embryology 146 (1975), S. 225-243 
    Details
    ISSN: 1432-0568
    Keywords: Differentiation ; Sympathetic ganglion ; Culture ; Electron microscopy ; Histochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Immature sympathetic ganglia prepared from 51/2- or 6-day-old chick embryos were cultured up to one month. The in vitro development was followed by phase microscopy, electron microscopy and using histochemistry for catecholamines, monoamine oxidase and cholinesterases. During the first week of culture extensive plexuses of nerve fibres were formed between and around the clusters of nerve cells. Mature-looking neurons were observed in the cultures by phase microscopy after three weeks, at which age the mean diameter of the perikarya was more than doubled. Varying catecholamine fluorescence was observed in the perikarya during the entire culture period. The nerve fibres showed usually only weak fluorescence, but, in the older cultures, bright varicosities were regularly found in the fibres. Monoamine oxidase activity was demonstrated already at three days of culture and the reaction was maintained positive. Weak or moderate acetyl-cholinesterase activity was demonstrated in the sympathicoblasts and young sympathetic neurons and their processes. The axolemma showed acetylcholinesterase activity also around the nerve terminals containing small dense cored vesicles. Reactions for the non-specific cholinesterases were negative. Electron microscopy of the 30-day-old cultures revealed that the clusters of nerve cells consisted of mature sympathetic neurons, which contained large (60–200 nm) and small (35–60 nm) granular catecholamine-storing vesicles. Glial cells were almost totally lacking. Large numbers of nerve terminals containing both large and small granular vesicles were observed in the clusters, often in synaptic contact with the sympathetic neurons. It is concluded that the primitive sympathicoblasts are, in favourable conditions, capable of differentiation in culture up to mature sympathetic neurons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00302172
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    In utero development and maturation of the retina of a non-primate mammal: A light and electron microscopic study of the guinea pig (1975)
    Springer
    Anatomy and embryology 146 (1975), S. 279-300 
    Details
    ISSN: 1432-0568
    Keywords: Retinogenesis ; Synaptogenesis ; Guinea pig ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A light and electron microscopic examination of retinogenesis in the fetal guinea pig has revealed an early development of synapses and photoreceptor cells. Differentiation of the neural retina begins around day 23 of gestation. By 34 days the retina reaches its maximum thickness. It differentiates an inner plexiform layer in which vesicle-containing processes and primitive synapses are evident. Synaptic ribbons are found in processes of this layer by 43–45 days of gestation. An outer plexiform layer develops within the neuroblast layer at 40 days of gestation; from its first appearance the outer plexiform layer contains synapses complete with synaptic ribbons. Receptor terminals of the α, paranuclear and β type are present well before birth. Photoreceptor cells form inner segments by 40 days; the formation of outer segments is indicated by 45 days but not widespread until 49 days. The retina appears mature by day 51–57. It is clear that the primate is not unique in the early differentiation of its retinal synapses relative to the time of maturation of its photoreceptor cells. The potential functional capacities of precocious retinae, and the mechanisms of synapse development are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00302175
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Melanogenesis in the pigment epithelium of chicken embryos (1975)
    Springer
    Anatomy and embryology 147 (1975), S. 177-187 
    Details
    ISSN: 1432-0568
    Keywords: Iris ; Melanogenesis ; Chicken embryo ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The iris anlage of 2–10 and 15 days old chicken embryos were studied histochemically, and by both light and electron microscopy. Light microscopic serial sections showed that pigmentation began at the outer layer of the posterior eye pole and progressed from there forwards to the optic cup margin. The entire outer layer of the optic cup as well as the pupillary margin were completely pigmented by the 4th day of incubation. By the 10th day the posterior iris epithelium was totally pigmented. Electron microscopical studies showed that the first premelanosomes appeared at about the 3rd day of incubation in the anterior iris anlage with the exception of the pupillary margin. It could be shown that melanogenesis progressed through the following steps: premelanosomes, followed by tyrosinase activity in a Golgi-associated system of smooth endoplasmic reticulum (GERL) and small vesicles and finally differentiation of the melanosomes. The possible origin of the premelanosomes and the formation of melanin are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00306732
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    An ultrastructural comparison of implantation in young and senescent golden hamsters (1975)
    Springer
    Anatomy and embryology 147 (1975), S. 293-307 
    Details
    ISSN: 1432-0568
    Keywords: Implantation ; Golden hamster ; Senescent ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Implantation was compared in young (3–5 month) and senescent (14–17 month) golden hamsters at 3, 31/2, 4, 41/2, 5, and 51/2 days of pregnancy (post-ovulation). One hundred twenty-two embryos (89 from 22 young females and 33 from 18 senescent females) located in utero by cutting thick sections (1–3 μm), were re-embedded and thin-sectioned for electron microscopy. Ultrastructurally implantation and embryonic differentiation was delayed approximately 12 hours in the senescent hamster when compared with young hamsters at the same stage of pregnancy. Failure of the blastocyst to implant would not appear to be a major cause of the declining litter size in aged golden hamsters.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00315077
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    A study of the perineurium in peripheral nerve pathology (1975)
    Springer
    Acta neuropathologica 33 (1975), S. 257-270 
    Details
    ISSN: 1432-0533
    Keywords: Perineurium ; Pathology ; Electron microscopy ; Homeostasis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The response of the perineurium to the following experimental systems was investigated by light and electron microscopy: nerve crush, cold lesion and microinjection of (a) histamine liberator, (b) potassium cyanide, (c) lysophosphatidyl choline (LPC). Where myelin breakdown occurred, lipid globules were seen within Schwann cells, macrophages and also perineurial cells. Where increased vascular permeability occurred, proteinaceous material leaked from endoneurial vessels into the endoneurial space and later appeared between perineurial laminae. It is suggested that the normal homeostatic function of the perineurium is extended in pathology to the removal of protein and lipid debris. In this way the perineurium contributes to the restoration of the normal microenvironment of peripheral nerve fibres.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00688398
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    Origin and ultrastructure of intra-hyphal hyphae in Trichophyton terrestre and T. rubrum (1975)
    Springer
    Archives of microbiology 106 (1975), S. 195-200 
    Details
    ISSN: 1432-072X
    Keywords: Trichophyton terrestre ; Trichophyton rubrum ; Hyphal fusions ; Origin of intra-hyphal hyphae ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A cell observation chamber was designed to perform continuous photomicroscopic observations of hyphal anastomosis and the origin of intra-hyphal hyphae in Trichophyton terrestre and T. rubrum. These data were correlated with ultrastructural features of intra-hyphal hyphae. Hyphal fusions occurred commonly in either species of Trichophyton when incubated alone. In T. terrestre, empty hyphal segments adjoined by live units were invaded at the septa from both directions by new hyphal ingrowth. Continuous observations revealed that the intra-hyphal hyphae subsequently anastomosed via a lateral fusion peg. Similar intra-hyphal hyphae were shown in T. rubrum. Electron microscopic studies revealed ascomycetous septa in both conventional hyphae and intra-hyphal hyphae. For the latter, the cytoplasm and wall of the inner hypha were bounded by cytoplasmic organelles and another cell wall of the outer hypha.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446523
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Micro-autoradiographic studies on host-parasite interactions (1975)
    Springer
    Archives of microbiology 105 (1975), S. 193-199 
    Details
    ISSN: 1432-072X
    Keywords: Bean ; Rust ; Haustorium ; Sheath ; Autoradiography ; Infection ; Electron microscopy ; Phaseolus vulgaris ; Uromyces phaseoli
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Tritium labeled uredospores of Uromyces phaseoli were produced be feeding the host, Phaseolus vulgaris, with 3H-orotic acid. These spores were allowed to germinate on and to penetrate into a bean leaf. 24 hrs after inoculation, the bean rust had formed the first haustorium. All fungal structures, including the fungus walls, were heavily labeled. No label could be detected in the cells that had come into contact with the hyphae. In the infected host cell, the haustorium was labeled heavily, but the sheath around the haustorium and the host cell remained free of label. These results indicate that no detectable amounts of label leach from the bean rust into the host at this stage of infection although it is known that the rust takes up many metabolites. Since the sheath remains free of label and all fungal structures are evenly labeled, it is concluded that the sheath is formed by the host.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00447137
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Symmetrical infantile thalamic degeneration with focal cytoplasmic calcification (1975)
    Springer
    Acta neuropathologica 33 (1975), S. 1-8 
    Details
    ISSN: 1432-0533
    Keywords: Thalamus ; Cytoplasmic calcospherules ; Non-dystrophic ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Infantile thalamic degeneration is a rare clinico-pathological entity. Restricted location of the lesion and peculiar cytopathological changes serve to distinguish this disorder from other common encephalopathies. Optical and ultrastructural studies demonstrate cytoplasmic calcopherules in previously viable cells. According to current concepts of acute cellular reactions to injury and mechanism of intracellular calcification, the cytological changes cannot be attributed to either hypoxic ischemic cell change or dystrophic calcification. By analogy to other human and pathological material, the most likely basis for nondystrophic calcopherule formation is toxic or infectious injury with local synthesis, or autophagic or phagolysosomal degradation of cellular debris of specific chemical composition favoring calcium deposition.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00685959
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    Epileptic activity and anatomical characteristics of different lesions in cat cortex. Ultrastructural study (1975)
    Springer
    Acta neuropathologica 33 (1975), S. 143-152 
    Details
    ISSN: 1432-0533
    Keywords: Electron microscopy ; Experimental epilepsy ; Oedema
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Three different types of lesions have been studied in the cortex of the cat, by means of electroencephalography and electron microscopy. These three types of lesions can be listed in order of increasing magnitude according to their capacity to induce abnormal electrical activity: 1. incision of the cortex gives paroxymal activity, 2. intracortical insertion of a resin pellet generates weak epileptic activity, 3. intracortical insertion of a cobalt resin pellet produces epileptic activity. A parallel can be drawn between electrophysiological and anatomical data: there seems to be a quantitative relationship between the degree of epileptic activity and the extent of perilesional tissue. Furthermore, in this perilesional tissue, oedema is observed, the intensity of which varies according to the type of lesion. Thus, the epileptic activity of a lesion seems to be proportional not only to the volume of the perilesional tissue but also to the development of the oedema.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00687540
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    Electron microscopic investigation of inclusion material in a case of adult metachromatic leukodystrophy; Observations on kidney biopsy, peripheral nerve and cerebral white matter (1975)
    Springer
    Acta neuropathologica 33 (1975), S. 165-171 
    Details
    ISSN: 1432-0533
    Keywords: Adult metachromatic leukodystrophy ; Brain ; Peripheral nerve ; Kidney ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structural characteristics of storage products in peripheral nerve, kidney and cerebral white matter, from a case of adult metachromatic leukodystrophy are described. There were pronounced differences from the fine structural aspects in late infantile cases. A large proportion of the inclusions did not exhibit a unit membrane. An hypothesis is proposed to clarify the delayed manifestation of this type of metachromatic leukodystrophy until adulthood.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00687542
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    Niemann-Pick disease (Crocker's type C) (1975)
    Springer
    Acta neuropathologica 33 (1975), S. 191-200 
    Details
    ISSN: 1432-0533
    Keywords: Niemann-Pick disease ; Storage distribution ; Cerebral vascular glycolipid ; Histochemistry ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A histochemical study is reported of regional differences of the lipid storage in a case of Niemann-Pick disease (NPD) type C. Besides tissues known to be affected (reticuloendothelium, hepatocytes, nervous system), storage was demonstrated in adrenal cortical spongiocytes, sweat glands, renal glomerular and tubular cells, smooth muscle, excretory tubules of some salivary glands, ependyma and in choroid plexus. In most tissues were stored sphingomyelin, cholesterol and a small amount of a glycosphingolipid. In the endothelium of cerebral and spinal vessels the main stored lipid was a glycosphingolipid. The significance of these regional differences are discussed and their study is recommended as a useful counterpart to the biochemical investigation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00688393
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    The myocardium in Lafora disease (1975)
    Springer
    Acta neuropathologica 33 (1975), S. 343-349 
    Details
    ISSN: 1432-0533
    Keywords: Lafora disease ; Myocardium ; Deposits ; Enzame histochemistry ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Histological, histochemical and electron microscopic studies on the myocardium of 3 Japanese patients with Lafora disease were carried out. Deposits in the myocardium stained positively with PAS, Best's carmine and Lugol's indine. After digestion of the sections with α-amylase, the deposits disappeared or were less intense, in particular with PAS staining. Phosphorylase activity was deficient in the myocardium of Case 3, when compared with controls, both of which were kept frozen at −20°C following autopsy. Electron microscopy revealed that the deposits were not membrane-bound and consisted of fine particles and fibrillae. The nature of the deposits is diseussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00686166
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    Vascular and neuroglial changes in experimental herpes simplex encephalitis (1975)
    Springer
    Acta neuropathologica 33 (1975), S. 245-256 
    Details
    ISSN: 1432-0533
    Keywords: Herpes simplex encephalitis ; Blood-vessels ; Reactive microglia ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Generalized vascular changes and diffused proliferation of reactive microglia were observed in an experimental model of HSV encephalitis of mice. The wide spread of these changes contrasted with the localized character of virus replication and the confined areas of damaged nervous tissue. The vascular and microglial changes were precocious in animals inoculated with concentrated virus suspension (105.5LD50) while they appeared late in mice inoculated with diluted virus suspension (100 LD50). After inoculation with U.V. inactivated virus no changes were seen. The results obtained in this study suggest that the vascular and microglial modifications are not related to a direct cytopathic effect of the virus but dependent on the amount of virus present in the central nervous system and linked to the virus DNA.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00688397
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Brain involvement in Whipple's disease (1975)
    Springer
    Acta neuropathologica 33 (1975), S. 275-278 
    Details
    ISSN: 1432-0533
    Keywords: Whipple's disease ; Macrophage ; Electron microscopy ; Brain involvement
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A man of 22 with Whipple's disease suffered from an acute febrile state and unconsciousness. Focal inflammatory lesions accompanied by large numbers of peculiar macrophages occurred in thalamus and basal ganglia. The electron microscopic findings conform to previous reports on brain involvement in Whipple's disease.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00688400
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    GM2-Gangliosidosis, AB variant (1975)
    Springer
    Acta neuropathologica 33 (1975), S. 207-226 
    Details
    ISSN: 1432-0533
    Keywords: GM2-Gangliosidosis, AB Variant ; Hexosaminidase A and B ; Electron microscopy ; Membranous cytoplasmic inclusions ; Zebra bodies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Clinical and neuropathological studies of a case of AB variant GM2-gangliosidosis have been presented. The patient was a 14 months old black female infant who had “black cherry spot” in the retinas. The total activities of β-galactosidase and N-acetyl-β-hexosaminidase, as well as the proportion of hexosaminidase A and B components in her serum and leukocytes were normal when the assays were carried out with artificial fluorogenic substrate. Diagnosis of GM2-gangliosidosis AB variant was established by an abnormal increase of GM2-ganglioside in the biopsied brain tissue, similar to classical Tay-Sachs disease. Her clinical manifestation appeared to be similar but somewhat milder than those of classical Tay-Sachs disease. Light microscopic features of the cerebral biopsy were also closely similar to Tay-Sachs disease and Sandhoff disease but gliosis and neuronal loss were less pronounced. Electron microscopic study revealed numerous membranous cytoplasmic bodies (MCB) and zebra bodies in neurons. In addition, varieties of large intracytoplasmic inclusions in astrocytes, a feature distinctly different from classical Tay-Sachs disease, were observed. Numerous cytoplasmic inclusions were also present in oligodendroglia, pericytes and microglial cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00688395
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    Formation and nature of swirl defects in silicon (1975)
    Springer
    Applied physics 8 (1975), S. 319-331 
    Details
    ISSN: 1432-0630
    Keywords: Self-interstitials in silicon ; Swirls ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Point defect agglomerates in dislocation-free silicon crystals, usually called “swirls”, have been investigated by means of high-voltage electron microscopy. It was found that a single swirl defect consists of a dislocation loop or a cluster of dislocation loops. By contrast experiments it could be shown that these loops are formed by agglomeration of self-interstitial atoms. Generally the loops have a/2〈110〉 Burgers vectors, but in specimens with high concentrations of carbon (∼1017 cm−3) and oxygen (∼1016 cm−3) also dislocation loops including a stacking fault were observed. In crystals grown at growth rates higher thanv=4 mm/min no swirls are observed; lower growth rates do not markedly affect the size and shape of the dislocation loops. With decreasing impurity content (particulary of oxygen and carbon) the swirl density decreases, whereas the dislocation loop clusters become larger and more complex. A model is presented which describes the formation of swirls in terms of agglomeration of silicon self-interstitials and impurity atoms.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00898366
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    Vinblastine-induced ultrastructural changes in perisinusoidal cells of the rat liver (1975)
    Springer
    Research in experimental medicine 165 (1975), S. 245-249 
    Details
    ISSN: 1433-8580
    Keywords: Vinblastine ; Liver ; Perisinusoidal cell ; Microtubules ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Vinblastine, given intravenously to rats, leads to disappearance of microtubules, formation of paracrystalline inclusions and accumulation of fat droplets in the cytoplasm of the perisinusoidal cells of the liver suggesting that microtubules of the perisinusoidal cells play a role in lipid metabolism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01971384
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    Production and fates of unique organelles (transosomes) in ovarian follicles of Gallus domesticus under various conditions. II (1975)
    Springer
    Cell & tissue research 163 (1975), S. 63-79 
    Details
    ISSN: 1432-0878
    Keywords: Avian follicles ; Oocytes ; Transosomes ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Production and fates of transosomes (sacs of ribosomes made in the follicular cells of an ovarian follicle and subsequently passed to the cytoplasms of the oocyte) have been studied by electron microscopy in ovaries of young chicks, a testosterone-treated hen, aged hens which had ceased laying eggs and a “non-layer” mutant. Study was also made of “primitive yolk” (vacuoles present in both follicular cells and ooplasms of small follicles of normally laying hens). It was found that both transosomes and vacuoles of primitive yolk were present in small oocytes of young chicks, and “non-layer” mutants. However, the transosomes deep within the ooplasms were present within lysosomal vesicles in both of these instances and the vacuoles containing primitive yolk were patently abnormal in the “non-layer” mutant. Very few transosomes or primitive yolk vacuoles were present within the ooplasms of follicles from a testosterone-treated hen or from those of aged hens which were no longer laying. In both of these latter cases such bodies were present in the follicular cells. However, many transosomes were seen to be in the process of being lysed within the cytoplasms of these follicular cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218591
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    Nerve ending specializations in the central ganglia of Planorbis corneus (1975)
    Springer
    Cell & tissue research 163 (1975), S. 99-110 
    Details
    ISSN: 1432-0878
    Keywords: Central neuropile ; Planorbis corneus ; Synapses ; Spinule complexes ; Varicosities ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The neuropile in the central ganglia of Planorbis corneus was studied by electron microscopy, using different fixatives. Several types of specialization were observed in the membranes of adjacent axonal processes, varying from only slight membrane thickenings to structures resembling desmosomes. Specialized structures similar to the ‘spinule complexes’ in mammalian brain are widely distributed in certain areas of neuropile. They consist of a small projection which invaginates a neighbouring neurone; the membranes are closely apposed and there is associated electron-dense material. The problem of identifying chemical synapses in this tissue is discussed. Many axonal processes are varicose, and it is suggested that varicosities may also be sites of transmitter release.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218593
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    The membrane systems of the cardiac muscle cell of Cirolana borealis Lilljeborg (Crustacea, Isopoda) (1975)
    Springer
    Cell & tissue research 163 (1975), S. 175-184 
    Details
    ISSN: 1432-0878
    Keywords: Cardiac sarcomeres ; Circolana borealis (Isopod) ; T-tubules ; Sarcoplasmic reticulum ; Couplings ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The membrane systems of the cardiac muscle cell of the isopod Cirolana borealis Lilljeborg are described. The sarcolemma invaginates at the level of the Z band, forming transverse tubules. Narrow tubules branch off in a longitudinal direction from these transverse and radially arranged TZ-tubules forming a transverse collar at each A-I level, where dyadic and triadic junctions are formed with the sarcoplasmic reticulum. Two different orientations of the coupling discs have been detected in the supercontracted sarcomere, and this observation has been discussed. Adjacent myofibrils are separated by a double layer of sarcoplasmic reticulum.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221725
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    Comparative histochemical and electron microscopic studies of the sinus and venous walls of the human spleen with special reference to the sinus-venous connections (1975)
    Springer
    Cell & tissue research 163 (1975), S. 519-533 
    Details
    ISSN: 1432-0878
    Keywords: Human spleen ; Sinus lining cells ; Pulp veins ; Histochemistry ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Sinus and venous walls of normal human spleens were studied with enzyme histochemical and electron microscopic methods. Particular attention was paid to the connections between sinuses and veins. Histochemically the sinus lining cells revealed a distinct naphthol-AS-acetate-esterase activity but no reaction for alkaline phosphatase. Venous endothelial cells were positive for the latter but negative for the former enzyme. In the sinusvenous junctional area there were no endothelial cells with reactivity for both enzymes. Electron microscopically both the sinus lining cells and the venous endothelial cells could be clearly characterized and therefore easily distinguished from one another on morphological grounds. There were no clear ultrastructural indications of transitional forms between sinus lining cells and venous endothelial cells in the sinus-venous area. According to these findings, sinus lining cells represent a specialized endothelium, but one with practically no morpholgical similarities to the venous endothelium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218497
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    The fine structure of the epidermis of two species of salmonid fish, the Atlantic salmon (Salmo salar L.) and the brown trout (Salmo trutta L.) (1975)
    Springer
    Cell & tissue research 163 (1975), S. 535-543 
    Details
    ISSN: 1432-0878
    Keywords: Epidermis ; Salmonids ; Mucous cells ; Mucus ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of epidermal mucous cells of two species of salmonid fish has been described. Mucous cells are, next to filament-containing cells, the most commonly encountered cells in fish epidermis. The development of the cells as they progress to the periphery has been characterised. They are initially difficult to distinguish from filament-containing cells: later, they can be recognised by the presence of much smooth-surfaced E.R. The mucigenesis and the subsequent secretion of mucus has been observed and it is essentially comparable to that which occurs in the mucous cells of the mammalian intestine. The mucous layer of the epidermal surface seems to mainly comprise of the products of these mucous cells and the “cuticle” seen in other species has not yet been observed in the salmonid species investigated here.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218498
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    Thick filaments in vertebrate smooth muscle (1975)
    Springer
    Cell & tissue research 156 (1975), S. 201-216 
    Details
    ISSN: 1432-0878
    Keywords: Smooth muscle ; Myofilaments ; Vas deferens ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Smooth muscle cells of the mouse vas deferens fixed with 5% glutaraldehyde contained three types of filaments, namely, thin (50–80 Å) filaments, intermediate (100 Å) filaments and thick (120–180 Å) filaments. However, in 2 out of 16 experiments, under identical conditions, the cells did not contain thick filaments. With OsO4 fixation, thin filaments were not prominent, the most obvious being thick (120–250 Å) and intermediate (100 Å) filaments. After soaking in a modified Ringer solution under no applied tension for one hour, thick filaments (120–180 Å) appeared prominently in smooth muscle cells of the mouse vas deferens and thin filaments were in ordered bundles. By 4 hours, thick filaments had increased in size and density, with thin filaments distributed randomly around them. After 8 hours in Ringer, thin filaments were diffuse and difficult to discern, while thick filaments were large (up to 300 Å) and electron-dense. Intermediate (100 Å) filaments were present in association with dark bodies. Physiological experiments indicated that the intracellular components responsible for the development of a mechanical response were still functional at this time. The presence of “thick filaments” is also reported in degenerating smooth muscle cells of the guinea-pig vas deferens in tissue culture.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221803
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    The differentiation of the acrosome in the spermatid of the budgerigar (Melopsittacus undulatus) (1975)
    Springer
    Cell & tissue research 156 (1975), S. 411-416 
    Details
    ISSN: 1432-0878
    Keywords: Acrosome ; Spermatid ; Budgerigar ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The development of the acrosome of the budgerigar spermatid was studied under the electronmicroscope. The acrosome arises from a granule derived from the Golgi apparatus which interacts with the nucleus to form a cone shaped acrosomal cap and a perforatorium. A quantity of cytoplasm and plasma membrane is captured from the cell periphery and incorporated into the substance of the acrosome. The possible significance of the developmental phases and comparative avian spermatology is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00225369
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    Intranuclear and cytoplasmic annulate lamellae in grasshopper spermatocytes (Genus Melanoplus) (1975)
    Springer
    Cell & tissue research 156 (1975), S. 475-482 
    Details
    ISSN: 1432-0878
    Keywords: Annulate lamellae ; Spermatocytes ; Grasshoppers ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Intranuclear and cytoplasmic annulate lamellae were studied in grasshopper spermatocytes (Melanoplus) with the electron microscope. Although cytoplasmic annulate lamellae were observed in all three species examined, intranuclear annulate lamellae were found in only one species. The intranuclear annulate lamellae encompass certain nuclear material adjacent to the nuclear envelope forming a vesicle that is extruded into the spermatocyte cytoplasm. In this same species, cytoplasmic annulate lamellae are seen contiguous with granular masses of varying size. These structures were noted as being morphologically indistinguishable from the “yolk nuclei” of dragonfly oocytes (Kessel and Beams, 1969; Kessel, 1973).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00225107
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    Electronic Resource
    Electronic Resource
    The fine structure of the iris of the grass frog, Rana pipiens (1975)
    Springer
    Cell & tissue research 158 (1975), S. 111-120 
    Details
    ISSN: 1432-0878
    Keywords: Iris ; Rana pipiens ; M. dilatator, sphincter pupillae ; Electron microscopy ; Photosensitivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The iris of the grass frog Rana pipiens, can respond to light even when isolated from the remainder of the animal. The iris is a three-layered structure, comprising a stromal layer and two layers of pigment epithelium. The sphincter pupillae, which is composed of pigmented smooth muscle cells, is embedded between the two layers of pigment epithelium. There is no dilator pupillae in this species. We have been unable to find any cells or any organelles in the iris which are anatomically specialized for photoreception in any obvious way.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219954
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 32
    Electronic Resource
    Electronic Resource
    Ultrastructural study of crystalloids in Sertoli cells of the normal, intersex and experimental cryptorchid swine (1975)
    Springer
    Cell & tissue research 158 (1975), S. 205-213 
    Details
    ISSN: 1432-0878
    Keywords: Sertoli cell ; Crystalloid ; Swine ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Spindle or needle-shaped crystalloids are observed in Sertoli cells of the intersex and experimental cryptorchid swine in the light and electron microscopes. Small crystalloids are also observed in Sertoli cells of the normal swine only by electron microscopy. These crystalloids consist of fine filaments. The filaments are about 5 nm in diameter and arranged parallel to the long axis of the crystalloid. In cross sections of the crystalloid, the close packing of the filaments shows hexagonal arrays. The interfilamentous distance is about 5 nm. In all animals examined, bundles of short filaments, which are 5 nm in diameter, are observed in the basal part of the Sertoli cells. Ultrastructural similarities among the crystalloids, the bundles of fine filaments, and the filamentous layer in the junctional specialization of the Sertoli cell are shown. These morphological similarities suggest that the crystalloids are formed by the aggregation of the bundles in the Sertoli cells of azoospermic testes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219961
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    The interstitial origin of germinal cells in the testis of the sticklebackThis investigation was supported by research grant AO657 from the National Research Council of Canada to D. B. McMillan. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 145 (1975), S. 295-317 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The brook stickleback, Culaea inconstans (Kirtland), in common with other bony fishes, lacks a germinal epithelium in the tubules of the testis, and the tubule wall is composed of a thin, discontinuous layer of myoid cells and collagenous fibers. Labelling of germ cells with tritiated thymidine has shown that the germ cells are derived from clumps of spermatogonia in the interstitial area. Large companion cells within the lumina of the tubules extend their processes to engulf spermatogonia from the interstitium which then enter the lumen of the tubule. Subsequent development of the germ cells takes place within individual compartments formed by folds of the plasma membrane of a companion cell. The companion cell, together with its complement of germ cells, constitutes a cyst. A companion cell may surround spermatogonia in the interstitium and at the same time encompass residual sperm of the previous season within the lumen. The plasma membranes of the germ cells and the companion cells remain discrete. Mature sperm are released into the lumen of the tubule and the companion cell again extends its processes into the interstitium and engulfs more spermatogonia for the following year.Companion cells may be homologous to the Sertoli cells of higher vertebrates although their processes penetrate the interstitium during the initial stages of spermatogenesis and they do not contain a permanent stock of spermatogonia.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051450304
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    The cardiac muscle in the pulmonary vein of the rat: A morphological and electrophysiological studyWork done in the Department of Morphology of the Faculty of Medicine of Ribeirão Preto, University of São Paulo, and Institute of Biophysics of the Federal University of Rio de Janeiro. Supported in part by the Fundação de Amparo à Pesquisa do Estado de São Paulo, grant 71/490 - médicas; by the Conselho de Pesquisas da Universidade Federal do Rio de Janeiro, by the Conselho Nacional de Pesquisas (Brasil), and by Banco Nacional de Desenvolvimento Econǒmico (Brasil) Contrato FUNTEC 143. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 145 (1975), S. 409-433 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The pulmonary veins of albino Wistar rats were studied by means of light and electron microscopy. The media of larger veins consists of cardiac muscle fibers which extend until the vessels attain about 100 μ in diameter. This coat consists of external longitudinal fibers and internal circular fibers. The vasa vasorum are well developed and the capillaries show pseudofenestrations. The numerous adrenergic and cholinergic nerve endings do not form typical motor end-plates as seen in skeletal muscles. The ultrastructure of these media muscle fibers is similar to that of rat hearts. The smooth muscle layer of larger pulmonary veins is not continuous as it is in smaller veins where it forms cushions. Comparisons of albino rats and other rodents reveal striking differences.Action potential shape and propagation velocity (0.5-1.2 m/s) along the myocardial coat of the pulmonary vein were similar to those observed in the left atrium and so was their sensitivity to locally applied acetylcholine. The physiological direction of propagation in rat pulmonary veins is toward the lung. This finding lends support to the hypothesis of a rhythmic, valve-like action of the striated musculature of the pulmonary venous wall during the systole and a possible role in the capacitance of the pulmonary circulation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051450403
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    Masthead (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975) 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460101
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    Cytological examination of reduction bodies of Corvomeyenia carolinensis harrison (Porifera: Spongillidae) (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 145 (1975), S. 483-491 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Freshwater sponges, Corvomeyenia carolinensis Harrison, were placed into tap water to induce degenerative reduction body formation. Reduction bodies were examined using light and electron microscopy in order to define their histochemical and ultrastructural characteristics. The reduction body of freshwater sponges is an extremely simple developmental system consisting primarily of an archeocyte reserve delimited by a simple squamous pinacoderm. The freshwater sponge reduction body displays many similarities to overwintering phases of marine sponges. The system presents an unusually straightforward vehicle for investigations of degeneration and regeneration as processes in developmental biology and may represent a reasonable vehicle in which to examine the process of the genesis of lysosomes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051450406
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    The aquiferous systems of three marine demospongiaePortions of this study were submitted for partial fulfillment of the M.A. degree in Zoology, University of California, Berkeley, California. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 145 (1975), S. 493-502 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The aquiferous systems of three common, coastal, marine Demospongiae, Halichondria panicea (Pallas), Haliclona permollis (Bowerbank) and Microciona Prolifera (Ellis and Solander), are analyzed by measurements of cross-sectional areas of conducting elements. The patterns in demosponges of extremely different organizational morphologies are found to be quantitatively similar. The porocyte nature of the ostia is established for all three species. Choanocyte chamber densities range from 1 to 1.8 × 107 chambers ml-1 with 57 to 95 choanocytes per chamber (means). Cross-sectional area of the intervillar space of the choanocyte collars is calculated to be 12 to 56 times the lateral surface area of the specimen. Velocities of water movement through specific elements of the aquiferous system are calculated from cross-sectional area data and measured oscular flow of Haliclona permollis. The calculated Reynolds numbers lie below the critical value and fluid flow is thus considered laminar throughout the aquiferous systems of these sponges.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051450407
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    Cytophysiological basis of disruptive pigmentary patterns in the leopard frog Rana pipiens. II. Wild type and mutant cell-specific patternsContribution Number 58 from the Amphibian Facility of the University of Michigan.,Supported in part by NSF GB 8187 to Dr. George W. Nace, University of Michigan. Data taken in part from a dissertation submitted to the University of Michigan in partial fulfillment of the requirements for the Ph.D. Manuscript preparation aided by grants from the Swarthmore College Faculty Research Fund, and NSF Institutional grant GU 3287 to George Washington University. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 35-54 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A new pattern index, Ip, is introduced and used to compare patterns of wild type, burnsi, and kandiyohi chromatophores in the leopard frog, Rana pipiens. Wild type chromatophores are hyperdispersed over distances within cellular contact, and it is concluded that this hyperdispersion results from contact-mediated negative interactions. The hyperdispersion is less strong in spot cells than interspot, and extends over larger areas in burnsi than in wild type epidermis. Over areas greater than chromatophore size, patterns are either random or clumped. Patterning of kandiyohi melanophores is clumped into aggregates small enough to be within the range of cellular contact, suggesting a lack of contact inhibition among these cells. The possible roles of cellular properties and the extracellular environment in pattern determination are discussed.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460103
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    Evidence for diaphragms in the pores of annulate lamellae and the nuclear membraneThis investigation was supported by a grant from the National Science Foundation GB 2374, and in part by funds from the Harris McLaughlin Foundation. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 81-95 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Interpretation of cross and tangential sections of the annulate lamellae and nuclear membrane of Rana pipiens oocytes provides evidence in these structures for the existence of diaphragms spanning the pores. The evidence appears to rule out explanations ascribing such diaphragms to an optical artifact. More detailed description is given of a component of the pore complex only briefly described heretofore and now called the “intracisternal ring.” The varied results and interpretations of studies of the pore complex in various cells are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460105
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    Electromyography and mechanics of mastication in the albino rat (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 1-33 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The masticatory apparatus in the albino rat was studied by means of electromyography and subsequent estimation of muscular forces.The activity patterns of the trigeminal and suprahyoid musculature and the mandibular movements were recorded simultaneously during feeding. The relative forces of the individual muscles in the different stages of chewing cycles and biting were estimated on the basis of their physiological cross sections and their activity levels, as measured from integrated electromyograms. Workinglines and moment arms of these muscles were determined for different jaw positions.In the anteriorly directed masticatory grinding stroke the resultants of the muscle forces at each side are identical; they direct anteriorly, dorsally and slightly lingually and pass along the lateral side of the second molar. Almost the entire muscular resultant force is transmitted to the molars while the temporo-mandibular joint remains unloaded. A small transverse force, produced by the tense symphyseal cruciate ligaments balances the couple of muscle resultant and molar reaction force in the transverse plane. After each grinding stroke the mandible is repositioned for the next stroke by the overlapping actions of three muscle groups: the pterygoids and suprahyoids produce depression and forward shift, the suprahyoids and temporal backward shift and elevation of the mandible while the subsequent co-operation of the temporal and masseter causes final closure of the mouth and starting of the forward grinding movement. All muscles act in a bilaterally symmetrical fashion.The pterygoids contract more strongly, the masseter more weakly during biting than during chewing. The wide gape shifts the resultant of the muscle forces more vertically and more posteriorly. The joint then becomes strongly loaded because the reaction forces are applied far anteriorly on the incisors. The characteristic angle between the almost horizontal biting force and the surface of the food pellet indicates that the lower incisors produce a chisel-like action.Tooth structure reflects chewing and biting forces. The transverse molar lamellae lie about parallel to the chewing forces whereas perpendicular loading of the occlusal surfaces is achieved by their inclination in the transverse plane. The incisors are loaded approximately parallel to their longitudinal axis, placement that avoids bending forces during biting. It is suggested that a predominantly protrusive musculature favors the effective force transmission to the lower incisors, required for gnawing. By grinding food across transversely oriented molar ridges the protrusive components of the muscles would be utilized best. From the relative weights of the masticatory muscles and their topographical relations with joints, molars and incisors it may be concluded that the masticatory apparatus is a construction adapted to optimal transmission of force from muscles to teeth.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460102
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    Masthead (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975) 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460201
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    Molting in stomatopod crustaceans. I. Stages of the molt cycle, setagenesis, and morphology (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 55-80 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The description of stages of the molt cycle in mantis shrimp (emphasizing Gonodactylus but compared in a number of Gonodactylidae, Squillidae, and Lysiosquillidae) includes data on texture, hardness, and color of the exoskeleton; behavior; and the micromorphology of the integument and developing setae.After stage A1, When the exoskeleton feels soft and soapy, and A2, when the abdomen attains parchment consistency, the exoskeleton continues to harden until stage C1, when the telson carinae can no longer be depressed with a fingernail. The propodus (C2) and the merus (C3) of the raptorial appendage are the last elements to become rigid. The meral spot achieves indistinct coloration at B1 and distinct but pale coloration at B2; body color continues to intensify until C4.Changes in behavior are particularly marked before and after the molt. After the molt defensive and avoidance behaviors characterize A1 and A2. Threatening increases from low to intense levels in A2 and B1. Striking and offensive behavior increase from weak to normal intensities from B2 to C4. One or two days before the molt, animals lower activity and dominance and feeding levels, exhibit reclusive behavior, and sometimes seal the cavity entrance.The morphology of setagenesis is particularly valuable for determining the stage of the molt after the exoskeleton hardens. The ratio of setae containing cellular contents throughout the lumen to those condensed into strands separates stages A2 through C3. “Cones,” although variable within and between individuals in some species, form initially in B2 and continue to condense through D. Initiation of C4, D0 and D1 overlaps variously in some individuals. Apolysis (D0) and morphogenesis of new setae (D1-D3) provide cues for identifying approach of the molt. Setagenesis and setal morphology differ among families, genera and some species of stomatopods. The structure and functional morphology of setae can be explained by the form of setagenesis.Passive swelling and active muscular peristalsis effect the shedding of the exoskeleton and setal eversion at the molt. The carapace and rostrum are shed as one unit. Patterns of meral sutures vary among taxa with enlargement of the merus and with subterminal or terminal ischiomeral articulation. Middorsal sutures open only on the sixth and seventh thoracic segments, suggesting loss of the first rather than the last abdominal segment and therefore a distant relationship to other eumalacostracans.Approximate durations of the molt stages in stomatopods are compared to those of 11 crustacean taxa. Extensive overlap seems to occur among midinterval stages, particularly in stomatopods. The developmental plateau occurs in different stages in different taxa. Late postmolt (C), associated with calcification, requires longer in more heavily calcified than in thinly calcified species, except for stomatopods. The physiological events immediately surrounding the the molt (A1-B1 and D3-D4) are compressed in time in crayfish, brachyurans, and especially in stomatopods. Behavioral adaptations maximize this compression of physiological events at the molt in stomatopods. These three groups also possess the most asymmetrical molt cycles of the crustacean taxa examined. It is hypothesized that these modifications of the molt cycle allow opportunistic molting and represent adaptations to agonistic behavior.Temporal variation in behavior and in color over the molt cycle may increase the potential for speciation by processes resembling neoteny.
    Additional Material: 25 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460104
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Structure development and evolution of the male pheromone system in some noctuidae (Lepidoptera) (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 129-175 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Pheromone systems from seven species of noctuid are examined. Much of the structure of scales from the wings and/or the abdomen is interpreted as a modification for secretion or release of a pheromone. Scales with an extremely complex surface provide a large evaporation surface, while those connected to secretory cells show less superficial folding than body-covering scales.The development of the secretory gland and diseminatory scales in Mamestra configurata is followed from the exuvial pharate adult stage to emergence. Both components are paired and develop from epidermal cells lining a pair of large lateral invaginations. They may have resulted through division of a group of less specialized cells that originally combined the function of pheromone production and release.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460107
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    Relationship of the sarcoplasmic reticulum to fibril and triadic junction development in skeletal muscle fibers of fetal monkeys and humans (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 97-127 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Examinations of stages of fibril development in muscle fibers of seven Rhesus monkey and six human fetuses reveal SR tubules encircling the Z lines at all stages of fibril development. The encircling SR tubules are continuous with the SR network of tubules which is found surrounding fibrils at all stages of development observed. The SR tubules encircling the Z lines show connections (electron-opaque strands) with the Z lines. The developing triadic junction shows a progressive increase in complexity of structures within the junction. First, membranes of T and SR become apposed with no visible structure between them. Second, tenuous connections are found traversing the space between apposed membranes. Third, well developed bridges are seen traversing the space. And finally, an intermediate density midway between the apposed membranes and parallel to them is found in favorable sections. Junctions between T tubule membranes were also observed and the structures in these junctions are somewhat similar to those found in junctions between T and SR membranes. The change in orientation of triads from predominantly longitudinal to predominantly transverse is complete in the 18-week monkey fetus and incomplete in the latest stage (28-week) of fetal development observed in humans.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460106
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    The maxillary palp organs of a wood-boring beetle, Melittomma sericeum (coleoptera, lymexylonidae) (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 123-135 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The complex and conspicuous basket-like structure attached to the third segment of each maxillary palp of Melittomma sericeum males is densely covered with tactile hairs on its outer or convex surface and with thinwalled chemoreceptors on its inner or concave surface. In a living male the structure is highly mobile and is extended laterally and ventrally. It evidently serves to detect odors produced by the female.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470202
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Smooth muscle cells in the rat testicular capsule: A developmental study (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 171-185 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: This study of the postnatal development (from 1 to 60 days) of smooth muscle elements in the rat testicular capsule has demonstrated that while such elements are identifiable by light microscopy at 30 days, myocytes are present at birth as seen by electron microscopy. The differentiation of smooth muscle from birth to 30 days has been described, by which time it is of adult morphology and content. Perhaps significantly, it is at 30 days that the testis achieves a scrotal position, although sexual maturity does not occur until about 60 days. Presumably, at 30 days the testicular capsule of the rat is capable of the spontaneous contractions which are known to occur in the adult and which are assumed to aid the transport of non-motile spermatozoa from the testis to the epididymis.The presence of occasional striated muscle fibers in the rat testicular capsule as reported previously has not been confirmed by this investigation, although their possible origin is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470205
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    A histochemical study of cervical motor neurons and the posterior latissimus dorsi muscle in normal and dystrophic chickens (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 155-169 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A chromatolysis study, 14 to 21 days following denervation, showed the spinal cord representation of the nerve to the posterior latissimus dorsi muscle to be in the ventrolateral cell column between cervical ganglia 14 and 15. To characterize cervical neurons not undergoing chromatolysis, histochemical studies were done on the cords of additional nondenervated animals. Staining reactions for beta-hydroxybutyrate dehydrogenase, succinic dehydrogenase and cholinesterase did not reveal any quantitative differences between motor neurons in cervical segments 14 and 15 of normal and dystrophic birds. Motor neurons are positive for beta-hydroxybutyrate dehydrogenase and succinic dehydrogenase, but the surrounding neuropil is positive for the latter only. No pseudochlinesterase activity is found in the ventral horn cells, but true cholinesterase is present in most of the neurons. With the periodic acid-Schiff reaction the dystrophic cords exhibit many neurons with large amounts of glycogen in them. Normal cords examined show either no glycogen positive cells or an occasional ventral horn cell with much glycogen in it. Normal muscles contain less succinic dehydrogenase and beta-hydroxybutyrate dehydrogenase positive fibers than dystrophic muscle. More periodic acid-Schiff positive fibers are present in normal muscles than in dystrophic muscle. The motor endplates in normal muscle contain only true cholinesterase. Both true and pseudocholinesterase activity is present in the motor endplates of dystrophic muscle.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470204
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    The feeding system of terrestrial tiger salamanders (Ambystoma tigrinum melanostictum baird) (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 137-153 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: High speed cinematography was used to record the feeding activities of terrestrial Ambystoma tigrinum melanostictum. A description of these activities based on films of more than 50 feeding sequences is presented, and the mechanical units involved are defined, described, and functionally analyzed. Evolutionary implications of the feeding system are discussed.In a typical feeding sequence, A. t. melanostictum stations and maintains its lower jaw 3-5 mm from the prey. The mouth is then opened to form a gape of ∼60° by raising the anterior end of the flexed skull and by elevating and advancing the trunk while the mental symphysis of the lower jaw remains stationary. As the mouth opens the bulging tongue is recontoured so that the posterior glandular region becomes the tip of the fully protruded tongue, which may extend 3 to 7 mm beyond the symphysis. Dorsally the protruded tongue has a deep central depression and pronounced anterolateral rims. The anterior rim collapses on contact, thereby engulfing the prey in a sticky trough that retains it during tongue withdrawal. The cervical region is then flexed and the skull snaps downward. If the prey resists the tongue and is captured by marginal teeth, A. t. melanostictum relies on repeated tongue protraction and retraction, in some cases accompanied by inertial feeding. Swallowing involves gular expansion and contraction, and is accompanied by eye depression. When the mouth is opened during ingestive activities, the lower jaw remains in place.Apparently, A. t. melanostictum uses the dorsal trunk, the cucullaris major and the robust heads of the depressor mandibulae muscles to open the mouth. During skull elevation the lower jaw is partially immobilized by the geniohyoideus, and rectus cervicis superficialis muscles. The subarcualis rectus I muscles are prime movers in tongue projection. Hebosteoypsiloideus muscles assist in tongue protrusion by slackening the rectus cervicis profundus muscles that would otherwise restrict anterior displacement of the otoglossal cartilage and copula. Tongue contouring is performed by the complex genioglossus musculature. Sublingual and anterolingual sinuses facilitate protrusion and contouring by providing space and lubrication. Rectus cervicis muscles (profundus and superficialis) are responsible for tongue withdrawal. Closure of the mouth is accomplished by the four levator mandibulae muscles, and again the lower jaw is immobilized, mostly by ventral longitudinal muscles.Skull-trunk elevation during prey capture and ingestion was also observed and filmed in several other species of Ambystoma, in Dicamptodon ensatus, and in two salamandrid species. Apparently raising and straightening the craniovertebral axis, while the mental symphysis retains contact with the substratum, is a common feature of urodele feeding systems, and does not require peculiar morphological adaptations.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470203
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    Evolution of the mammalian middle ear (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 403-437 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The structure and evolution of the mandible, suspensorium, and stapes of mammal-like reptiles and early mammals are examined in an attempt to determine how, why, and when in phylogeny the precursors of the mammalian tympanic bone, malleus, and incus (postdentary jaw elements and quadrate) came to function in the reception of air-borne sound. The following conclusions are reached.It is possible that at no stage in mammalian phylogeny was there a middle ear similar to that of “typical” living reptiles, with a postquadrate tympanic membrane contacted by an extrastapes. The squamosal sulcus of cynodonts and other therapsids, usually thought to have housed a long external acoustic meatus, possibly held a depressor mandibulae muscle.In therapsids an air-filled chamber (recessus mandibularis of Westoll) extended deep to the reflected lamina and into the depression (external fossa) on the outer aspect of the angular element. A similar chamber was present in sphenacodontids but pterygoideus musculature occupied the small external fossa. The thin tissues superficial to the recessus mandibularis served as eardrum. Primitively, vibrations reached the stapes mainly via the anterior hyoid cornu, but in dicynodonts therocephalians, and cynodonts, vibrations passed mainly or exclusively from mandible to quadrate to stapes and the reflected lamina was a component of the eardrum.In the therapsid phase of mammalian phylogeny, auditory adaptation was an important aspect of jaw evolution. Auditory efficiency, and sensitivity to higher sound frequencies, were enhanced by diminution and loosening of the postdentary elements and quadrate, along with transference of musculature from postdentary elements to the dentary. These changes were made possible by associated modifications, including posterior expansion of the dentary. Establishment of a dentray-squamosal articulation permitted continuation of these trends, leading to the definitive mammalian condition, with no major change in auditory mechanism except that in most mammals (not monotremes) the angular, as tympanic, eventually became a non-vibrating structure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470404
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    Evidence for a structural relationship between successive parallel tubules in the SR network and supernumerary striations of Z line material in purkinje fibers of the chicken, sheep, dog and rhesus monkey heart (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 459-473 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The striations and the intervening filaments observed in the present study have been variously designated in the literature as: prodromal pattern, leptomeric myofibril, microladder, leptomeric organelle, leptofibril and zebra body. Electron microscope examinations of Purkinje fibers from the septa, papillaries, trabeculae carneae and small endocardial strands from chicken, sheep, dog and monkey hearts have revealed a close association between densely stained striations of supernumerary Z line material and successive parallel tubules in the network formed by the sarcoplasmic reticulum (SR). The striations appear to be linked together by filaments that somewhat resemble the part of thin filaments attached to Z lines in normal fibrils. The evidence for a close association of striations and SR tubules is derived from a similarity of spacing between striations and successive parallel tubules in the SR network and from a resemblance of striation and SR network patterns. The evidence for a structural relationship between striations and SR tubules is derived from the observation of electron-opaque strands traversing the space between striations and SR tubules.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470406
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    Dynamics and acoustical radiation of Porichthys notatus' swim bladder system (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 145 (1975), S. 327-335 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The swimbladder system of the plainfin midshipman consists of a gas-filled bladder and two intrinsic sonic muscles which are attached to the bladder at opposite sides. An experimental and analytical study was conducted to define the physical characteristics of this dynamic system, and to relate these characteristics to radiated acoustical pressure pulses. Results indicate that the system has two degrees of freedom, being comprised of two inertial, stiffness and damping components; the first and second mode components of a 23.1-centimeter midshipman are 0.002 and 0.019 kg (inertial) 2130 and 106,000 newtons per meter (stiffness) and 0.25 and 0.10 (damping) respectively. This system is excited by the sonic muscle forcing function which equals \documentclass{article}\pagestyle{empty}\begin{document}$ 0.00236{\rm}\sin \frac{{2\pi {\rm t}}}{{0.0045{\rm}\sec}}{\rm newtons}. $\end{document}Two system frequency response peaks were observed; the first was 110 hertz, at the flat section next to the sonic muscle, and was very near the repetition frequency of the sonic muscle pulses; the second was 350 hertz, at the hemispherical section, which was the frequency of the acoustical pressure pulse. These phenomena describe a dynamical system closely “tuned” to its forcing function, and a system which is highly responsive to acoustical pressure pulses radiated by neighboring midshipmen. The acoustical pressure pulse coincides in wave form with the hemispherical bladder wall acceleration.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051450306
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 52
    Electronic Resource
    Electronic Resource
    Mitochondrial changes in flight muscles of normal and flightless Drosophila melanogaster with age (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 145 (1975), S. 337-353 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Fine structural changes in mitochondrial morphology pertaining to size, number and growth were examined in flight muscles of normal and experimentally dewinged male Drosphila melanogaster ranging up to 26 days of age. In the normal winged flies, the number of mitochondria decreases during the first week of adult life whereas the size of individual mitochondrial profile increases significantly. Changes in mitochondrial size and number are due to the fusion of mitochondria. Fused mitochondria are extremely large in size and irregular in shape. In 26-day old normal flies, the number of mitochondria increases while the mitochondrial size is reduced indicating mitochondrial division. In comparison to the normal flies, dewinged flies exhibit a similar degree of mitochondrial fusion and growth during the first week of life. However, the extent of mitochondrial fission in 26-day old dewinged flies is greater than in the normal flies of this age. Structural mechanisms of mitochondrial fusion and fission are described. The objective of this study was to examine the relative effects of age and flight activity on the mitochondria.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051450307
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 53
    Electronic Resource
    Electronic Resource
    A Golgi study of the optic tectum of the Tegu lizard, Tupinambis nigropunctatus (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 215-227 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The dendritic patterns of cells in the optic tectum of the tegu lizard, Tupinambis nigropunctatus, were analyzed with the Ramon-Moliner modification of the Golgi-Cox technique. Cell types were compared with those described by other authors in the tectum of other reptiles; particular comparisons of our results were made with the description of cell types in the chameleon (Ramón, 1896), as the latter is the most complete analysis in the literature. The periventricular gray layers 3 and 5 consist primarily of two cell types  -  piriform or pyramidal shaped cells and horizontal cells. Cells in the medial portion of the tectum, in an area coextensive with the bilateral spinal projection zone, possess dendrites that extend across the midline. The latter cells have either fusiform or pyramidal shaped somas. The central white zone, layer 6, contains fibers, large fusiform or pyramidal shaped cells, fusiform cells, and small horizontal cells. The central gray zone, layer 7, is composed predominantly of fusiform cells which have dendrites extending to the superficial optic layers, large polygonal cells, and horizontal cells. The superficial gray and white layers, layers 8-13, contain polygonal, fusiform, stellate, and horizontal elements. Layer 14 is composed solely of afferent optic tract fibers.Several differences in the occurrence and distribution of cell types between the tegu and the other reptiles studied are noted. Additionally, the laminar distribution of retinal, tectotectal, telencephalic, and spinal projections in the tegutectum can be related to the distribution of cell types, and those cells which may be postsynaptic to specific inputs can be identified. The highly differentiated laminar structure of the reptilian optic tectum, both in regard to cell type and to afferent and efferent connections, may serve as a model for studying some functional properties of lamination common to cortical structures.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460204
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 54
    Electronic Resource
    Electronic Resource
    Masthead (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975) 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460301
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 55
    Electronic Resource
    Electronic Resource
    Post embryonic development of the central nervous system of the spider Argiope aurantia (Lucas)This paper is dedicated to the memory of Prof. K. Pampapathi Rao on the first anniversary of his death. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 325-342 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Volumetric and histological changes of the central nervous system were studied during post embryonic development of a spider, Argiope aurantia.The neural mass of Argiope grows allometrically with respect to volume of the cephalothorax and body weight. In the first instar 46% of the cephalothoracic volume constitutes the neural mass and this is reduced to 4% in the female (9th stage) and 12% in the male (7th stage) spider.Growth curves for the cephalic ganglion, measured at all stages, represent a straight line. The neural mass of females is two and a half times larger than that of the males. The ganglion increased 24 fold in female and 10 fold in male spiders. Addition of neural mass occurs in all stages.The brain volume is greater than that of the subesophageal ganglion in the first two instars. In subsequent stadia, the subesophageal ganglion grows faster, and in females it is finally three times and in males two times larger than the brain.Growth of cortex and neuropile depict exponential curves. Comparison of growth patterns of these shows an inverse relationship during development. While the volume of the cortex is higher in the first two or three stages, the volume of the neuropile is higher in the remaining stadia. The causes for this growth pattern are discussed.Counts of cell numbers show that there is a constant population of neurons throughout the post-embryonic development. The number of nerve cells in females is higher than in males, 11% in the subesophageal ganglion and 58% in the brain.The growth of the cortex is partly accomplished by an increase in cell volume. In male and female spiders the increase in Type-B cells is 20 and 50 fold, while that of large motor neurons is 200 and 600 fold respectively. The motor neurons of 20 μ and above number 63 in male and 916 in female adult spiders.The growth of neuropile occurs through an increase of dendritic arborization and axonal branching. The largest axons measure 1 μ in the first and 16 μ in adult stages. An increase of incoming sensory fibers is also noticed during development.Invasion of neural lamella into cortex and neuropile increases during development. Neural lamella which are 1-2 μ in the first stage grow to 40-100 μ thickness in adult female spiders, near the origin of the main nerves. One type of astral cells, counted in neuropile, increases 10 fold.The appearance of a central body and the beginning of web construction coincide during the second instar. The relationship between these two is discussed.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460303
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 56
    Electronic Resource
    Electronic Resource
    Auditory systems of Heteromyidae: Functional morphology and evolution of the middle ear (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 343-376 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Middle ears (515) from 26 species of the rodent family Heteromyidae  -  genera Dipodomys, Microdipodops, Perognathus, and Liomys  - were studied both grossly and histologically, for qualitative and quantitative comparisons. Middle ear modifications characteristic of each genus are qualitatively described. Quantitative comparisons are made among the 26 species in the study. Some correlations between middle ear size and other measurements are discussed.The middle ear is an acoustical transformer that for best efficiency must match the impedance of the cochlea to the impedance of the air in the external auditory meatus. It accomplishes this by a pressure increase and a velocity decrease through the combined effects of the lever and areal ratios; however, because the important consideration is a matching of two impedances rather than an absolute pressure increase, the pressure transformer ratio is a less informative measure of the middle ear's efficiency than is the impedance transform ratio. The impedance transformer mechanism is explained (from a morphological point of view), and equations are presented. Dipodomys, Microdipodops, and Perognathus have a theoretical transmission (at the resonant frequency) of 94-100% of the incident acoustical energy; Liomys, 78-80%. The areal ratio of stapes footplate to 2/3 tympanic membrane is remarkably constant among the species, varying only from 0.04 to 0.07: in Dipodomys and Microdipodops this small ratio is due to the very large tympanic membrane; in Perognathus and Liomys it is due to the extremely small stapes footplate. The lever ratio of incus to malleus varies from 0.28 to 0.33 in Dipodomys and Microdipodops, from 0.37 to 0.46 in Perognathus, and from 0.55 to 0.60 in Liomys. In addition, the middle ear volumes and the morphology of tympanic membrane, ossicles, ligaments, and muscles, all combine to minimize both mass and stiffness. All these data suggest middle ear mechanisms which are very efficient over a broad frequency range.The middle ear modifications found in heteromyids are adaptive in predator avoidance, especially in areas of little natural cover; nevertheless, contrary to expectations, there is no firm relationship between habitat and the extent of these modifications in the 26 species. However, environment did apparently play an important role in the evolution of the family, and this is discussed.
    Additional Material: 31 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460304
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 57
    Electronic Resource
    Electronic Resource
    Auditory systems of Heteromyidae: Postnatal development of the ear of Dipodomys merriamiThis research was supported in part by grants NS-05800 and NS-11459 from National Institutes of Health. The author appreciates the assistance of M. Webster. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 377-393 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Serial histological sections of kangaroo rats of postnatal ages 0-, 3-, 7-, 10-, and 14-days were prepared and studied. At birth the middle ear is mostly filled with mesenchyme and small in size, having only a small hypotympanum and a very small epitympanic recess. During the first postnatal two weeks, much of the hypertrophy found in the adult middle ear develops. Because an entotympanic element is never formed, the previously called entotympanic chamber is here renamed the hypotympanum. The epitympanic recess greatly expands to form what has been called the dorsal (or anterior) mastoid sinus. Since this chamber has no relation to the mastoid, it is here renamed the epitympanum. Posteriorly, the previously called posterior mastoid sinus develops from the growth of the hypotympanum into and beyond the region of the posterior and horizontal semicircular canals. In development and adult position it is comparable to the primate antrum and so is here renamed the antrum.At birth the organ of Corti is very immature but its major cell types can be identified. During the first two weeks of development the following events occur: (1) the vas spirale disappears, (2) the inner spiral sulcus cells atrophy, (3) the hair cells and supporting cells mature, (4) the cells of Hensen differentiate with their apical processes elevating the reticular lamina, (5) the innermost cell of Claudius migrates under and supports the Hensen's cells, and (6) the hyaline mass of the zona pectinata of the basilar membrane loses its connective tissue cells and expands in size. The developmental events support the previous description and identification of Hensen's and Claudius' cells.
    Additional Material: 25 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460305
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 58
    Electronic Resource
    Electronic Resource
    Masthead (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975) 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470201
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 59
    Electronic Resource
    Electronic Resource
    Development of the head skeleton and pectoral girdle in Esox (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 61-88 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A consideration of head development in two species of Esox, lucius and americanus (ssp. vermiculatus) representing the two subgenera Esox and Kenozoa respectively, focused on the significance of the variations of the latero-sensory canal system, its associated bones, and other skeletal elements. In living forms only aspects of “regression” or specialization can be studied. Canals tend to be reduced to pit lines first at their termini but can be broken in their course. Pit lines range from nearly canals to surface structures, or even fail to develop. The number of neuromasts varies. Canal bones develop from two centers: neuromast related and deeper membranous centers which may have no relationship to neuromasts. Tooth-bearing and non-canal-related dermal bones have only membranous (original) centers. The number of neuromasts associated with a bone usually does not affect its development or form. In the case of the circumorbital bones, the extrascapulars, and the nasal, a one to one relationship has developed by regression - towards the development of the latero-sensory component only. The idea that reductions in bone number are commonly traceable to fusion is rejected although examples of fusion are known. Most bones that disappear are simply lost (no blastema or other evidence of their presence seen in development). The relationship between dermal bone and chondral bone is examined and there is evidence of the former giving rise to the latter. The ontogenic order of appearances shows a feeding (functional) correlation.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470106
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 60
    Electronic Resource
    Electronic Resource
    Organization of the teleostean nucleus rotundus (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 89-107 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The nucleus rotundus of 21 species of teleosts was studied by a modified Bodian and the Golgi method to clarify the histological organization, with special reference to the cell lamination and the glomerular formation.The common components of the nucleus in all species are as follows: a thick fiber bundle which comes from the commissura horizontalis and enters the nucleus from the dorsal surface, many small cells, large cells, glomeruli, and a surrounding fibrous capsule. The nuclei of all species studied are classified into three types mainly on the distribution of the small cells, and to a lesser degree on the location of the large cells and the glomeruli.The first type of nucleus has small cells. large cells and glomeruli throughout its extent. In the second type of nucleus, many small cells form a peripheral cell layer, while the large cells and glomeruli are found all over the nucleus.The third type of nucleus is clearly laminated. It is composed of four layers arranged concentrically around a central fiber net in the following order: a glomerular layer, a fibrous layer, a small-cell layer, and a peripheral fibrous capsule. In some species, the large cells are located in the fibrous capsule, and all glomeruli contain a star-like structure, which corresponds to the tips of the large cell dendrites.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470107
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 61
    Electronic Resource
    Electronic Resource
    Morphology of lymphoid organs in a cichlid teleost, Tilapia mossambica (Peters)Supported in part by a grant (01-077) from the U. S. National Institutes of Health, under special foreign currency research program (PL-480). (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 109-121 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: In Tilapia mossambica organized lymphoid tissues are present in the thymus, head-kidney and spleen, whereas they are lacking in pericardial tissue, liver, mesonephros, intestine and rectum. No lymphoid tissue was observed in the chondrocranium and cartilaginous viscerocranium of young adults.The thymus in Tilapia is encapsulated by thin strands of collagen fibers and consists of outer, middle and inner zones. While middle and inner zones are comparable to the thymic cortex and medulla of higher vertebrates, the homology of the outer zone is not clear. At the anterior end of the thymus, a loose aggregation of lymphocytes without a definite boundary has been observed.The head-kidney is characterized by the presence of lymphoid follicles, a subcapsular sinus, a hilus-like area and lymphatic vessels. The spleen is grossly divisible into white pulp and red pulp; the white pulp contains only a reticular area without definite lymphoid centers and the latter contains predominantly erythrocytes. Morphological changes in the lymphoid organs associated with immune response have been discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470108
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 62
    Electronic Resource
    Electronic Resource
    Structure and function of the head in flabelligerid polychaetesMost of this material forms a portion of a dissertation submitted to the faculty of the University of Southern California in partial fulfillment of the requirements for the Ph.D. degree. Contribution number 16 from the Santa Catalina Marine Biological Laboratory. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 187-207 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The functional anatomy of the head of Flabelliderma commensalis is described and compared to other flabelligerid polychaetes. Prostomial parts include the dorsal lip, the palps, two pairs of nuchal organs, four eyes and the prostomial lobe and ridge. The eyes are inverse pigment cup types with the medial portions of the sensory cells expanded to form a clear lens-like body. Peristomial parts include the median and ventral lips, the branchial membrane and the branchiae. The derivation of the nephridiopore is unknown. The spiraled branchiae of Coppingeria and the gill books of Diplocirrus are newly described variations in branchial structure. The head is retractable in some species and the anterior setigers are modified to form a protective setal cage. Two methods are employed for feeding: one for host fecal pellets and the other for detrital materials. Chemoreception, respiration, feeding and cleaning rely on a complex pattern of ciliary currents.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470206
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 63
    Electronic Resource
    Electronic Resource
    A reconsideration of the phylogeny of the tetrapod heart (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 209-228 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: After dissecting a variety of vertebrate hearts and extensively reviewing the literature, I have drawn some conclusions concerning the phylogeny of the tetrapod heart that differ from commonly expressed viewpoints in the literature. It is probable that the absence of an interventricular septum in amphibians is a primitive feature (rather than representing a loss). The complete interventricular septum of crocodilians and birds probably evolved primarily from the major horizontal septum of the typical (noncrocodilian) reptilian heart, with a smaller part representing a new development. The interventricular septum of mammals probably also evolved primarily from the reptilian horizontal septum. There is no reason to assume that the mammalian heart and aortic arches evolved directly from a pre-reptilian stage, as is often assumed. The evidence upon which these conclusions are based is given.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470207
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 64
    Electronic Resource
    Electronic Resource
    Masthead (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975) 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470301
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 65
    Electronic Resource
    Electronic Resource
    Trophotaeniae, embryonic adaptations, in the viviparous ophidioid fish, Oligopus Longhursti: A study of museum specimensContribution No. 37 of the New York Ocean Science Laboratory. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 385-401 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Prepartum embryos obtained from old museum specimens of the ovo-viviparous fish, Oligopus longhursti, possess external intestinal appendages. They are structurally identical to the trophotaeniae described by Turner ('37) and Mendoza ('37) in goodeid fishes. This is the first report of trophotaeniae in the viviparous ophidioids. Two developmental Stages, A and B, were observed. A is a tailbud stage, 2.0-2.25 mm in length, and B is a finfold embryo, 3.0-3.25 mm in length (Wourms and Bayne, '73). Trophotaeniae occur in the form of a single median anterior process and a pair of median posterior processes. They originate from a conspicuous peduncle formed around the anus. The processes of stage A are 1.5-2.0 mm long, 0.05 mm in diameter at their base and 0.04 mm at their tip. The stage B processes are 2.75-3.00 mm long, 0.075 mm in diameter at their base and 0.050 mm at their tip. Serial sections show that the surface epithelium of the trophotaeniae is continuous with and identical to the surface epithelium of the trophotaeniae is continuous with and identical to the surface epithelium of the embryonic gut. Examination both by transmission and scanning electron microscopy confirms that the apical surface of the trophotaenial epithelium and intestinal epithelium are covered with microvilli. Trophotaeniae are considered to function in the uptake of nutrients since they are structurally identical to intestinal epithelial cells. We suggest that maternal nutrients absorbed by trophotaeniae rather than yolk reserves are the principal source of embryonic metabolites. Trophotaeniae may afford a selective advantage since their existence in O. longhursti maximizes the number of large size embryos which a female can produce at one time. Occurrence of trophotaeniae in ophidioid, goodeid and zoarcid embryos is a remarkable example of convergent evolution.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470403
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 66
    Electronic Resource
    Electronic Resource
    Oocyte differentiation in Urechis caupo (echiura): A fine structural study (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 475-505 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The fine structure of oocytes of Urechis caupo is described for seven arbitrary stages ranging from the smallest oocytes (7μm in diameter) in the coelom to the mature oocytes (115 μm in diameter) in the storage organs. Although most types of cytoplasmic organelles accumulate more or less continuously, yolk granules do not appear until oocytes reach a diameter of 35 μm, and there is stage-specific synthesis of cortical granules in 60-80 μm oocytes. In the nucleus a single nucleolus first appears when an oocyte is 15 μm in diameter. Then a nucleolus satellite, which is about 3 μm in diameter, forms in 30 μm oocytes; this nucleolus satellite later (60-70 μm oocytes) becomes surrounded by 750 nm dense spherical bodies. Large (2-4 μm in diameter) juxtachromosomal spherules occur only in the nuclei of mature oocytes. Microvilli become progressively more numerous and longer until the oocytes reaches a diameter of 90 μm their tips project 1 μm beyond the fibrous surface coat, which is 2 μm thick when well developed. Near the end of oocyte growth, the microvilli retract into the surface coat leaving their pinched-off tips adhering to the outside of the coat.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470407
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 67
    Electronic Resource
    Electronic Resource
    The long-term organ culture of tissues from adult Necturus maculosus, the mud puppy (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 145 (1975), S. 319-325 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Fragments of Necturus maculosus liver, spleen and kidney were cultured at 25°C in 50% Minimal Essential Medium (MEM) or 50% Leibovitz L-15 Medium (L-15) for up to 49 days. The integrity of tissue structure was evaluated, hepatocyte cell and nuclear volumes were measured, the respiration rates of freshly-isolated and cultured liver fragments were determined, and the mitotic incidences in cultured liver, spleen and kidney were estimated. The addition of adrenalin caused a reduction in the glycogen content of liver cultures, and the subsequent addition of insulin resulted in a net increase in glycogen synthesis. Glycogen levels fell in fragments cultured in L-15, but rose in cultures in MEM. Arginase and ornithine transcarbamylase levels fell gradually throughout a 49-day culture period in L-15. Evidence presented supports the position that the survival of tissues in vitro is related to cell size and respiration rate. These experiments show that N. maculosus is a suitable donor of tissues for long-term organ culture studies on the maintenance and control of tissue-type specific structure and function.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051450305
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 68
    Electronic Resource
    Electronic Resource
    Neurosecretory system of the American dog tick, Dermacentor variabilis (Acari: Ixodidae). II. Distribution of secretory cell types, axonal pathways and putative neurohemal-neuroendocrine associations; comparative histological and anatomical implicationsIn part, from a dissertation by the senior author submitted in partial fulfillment of requirements for the Ph. D. degree in Entomology, The Ohio State University, Columbus. Supported by NIH Training Grant 5 T01 AI 00216 through the Acarology Laboratory, The Ohio State University.Supported in part by Public Health Service Research Grant AI-09556 from the National Institute of Allergy and Infectious Diseases (Principal Investigator, J. H. Oliver, Jr). (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 145 (1975), S. 269-293 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Histological observations using specialized techniques reveal neurosecretory cells in 18 centers throughout the rind (cortex) of the central nerve mass or synganglion of Dermacentor variabilis. Many cells contribute to complicated networks of neurosecretory pathways and tracts in pre- and post-esophageal portions of the synganglion. The four types of neurohemal-neuroendocrine associations found in Dermacentor resemble structures found in soft ticks (Argasidae) and in other Arachnida, but are more diverse than those described from any other single species. Neurosecretory terminals are distributed diffusely and in two concentrated associations within the perineurium of the synganglion and major peripheral nerves. Terminals are also distributed in the perineurial layers of lateral segmental organs which lie in the general hemocoel at the level of the pedal nerves. A retrocerebral organ complex surrounds the esophagus at its junction with the midgut. The complex includes dorsal and ventro-lateral lobes (containing neurosecretory terminals and intrinsic secretory cells) and the proventricular (neurohemal) plexus. This plexus seems to be a modified (concentrated) cardioglial association. Cardioglial associations are also formed by the neurosecretory innervation of vascular walls of the dorsal aorta and circulatory sinuses which envelope the synganglion and major peripheral nerves. Inferential considerations of neurosecretory and endocrine interactions in the Acari are based on these anatomical and histological data which also provide the basis for evolutionary considerations of anatomical relationships and specializations in the neurosecretory systems of other Arachnida.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051450303
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 69
    Electronic Resource
    Electronic Resource
    Masthead (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 145 (1975) 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051450401
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 70
    Electronic Resource
    Electronic Resource
    Muscle activity in rat locomotion: Movement analysis and electromyography of the flexors and extensors of the elbowPortions of this study were reported on at the 1974 meetings of the American Association of Anatomists in Cleveland, Ohio. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 177-196 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Footfall patterns and time sequence of activity are described for white rats conditioned to run freely in an activity wheel (which they drive). Motion is described in terms of soft contact, hard contact, soft contact, and flip phases. Duration of stride decreases and length of stride increases from walk to trot to canter to gallop. Myographic analysis shows that the brachialis has a major tonic function after it fires strongly during the flip phase and during much of the hard contact phase. Animals running at canter or gallop show major asymmetries between forelimb muscles on the first paw and on the lead paw sides.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460202
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 71
    Electronic Resource
    Electronic Resource
    Cytological events leading to the cleavage of golden hamster zygotes (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 197-213 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Fertilized golden hamster eggs were examined between 6 and 20 hours post-ovulation to determine the events leading to the two-cell stage. Following their migration the pronuclei remain in the central region of the zygote for approximately ten hours. The morphologically, indistinguishable male and female pronuclei remain relatively unchanged during this period, i.e., they do not interdigitate or fuse with one another as described for the zygotes of other organisms. Following this period and at the time of pronuclear breakdown elongate vesicles appear along the nucleoplasmic surface of the pronuclear envelopes. Later the pronuclear envelopes fragment into elongate cisternae; these and the vesicles formed along the inner lamina of the pronuclear envelopes remain closely associated and constitute quadrilaminar structures. The chromosomes which condense prior to and during pronuclear envelope breakdown, migrate to the equatorial plate of the forming cleavage spindle. After cytokinesis the chromosomes in the blastomere nuclei disperse. Increase in the nuclear envelope to accomodate this dispersion may involve the addition of membrane from the quadrilaminar structures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460203
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 72
    Electronic Resource
    Electronic Resource
    Aspects of germinal cyst and sperm development in Poecilia latipinna (Teleostei: Poeciliidae) (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 229-249 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The structure of the testis of Poecilia latipinna is described with particular reference to Sertoli cell-germ cell relationships during development and maturation of the germinal cyst. The cyst develops when primary spermatocytes become surrounded by a single layer of Sertoli cells at the testis periphery. As spermatogenesis and then spermiogenesis proceed, the cyst moves centrally in the testis toward the ducts comprising the vasa efferentia. In addition to being a structural part of the germinal cyst, the Sertoli cells phagocytize residual bodies cast off by developing spermatids and form an association with mature sperm, which resembles that observed in mammals, before the sperm are released into the vasa efferentia as a spermatozeugmata.The results of this investigation are discussed in view of what is known concerning testis structure in other teleosts and similarities between cell functions in teleosts and mammals. It is concluded that teleost Sertoli cells, teleost lobule boundary cells and mammalian Sertoli cells are homologous.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460205
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 73
    Electronic Resource
    Electronic Resource
    External morphology of antennae and their sense organs in the roach Gromphadorhina brunneri (Blattoidea: Dictyoptera)This investigation was supported by DeutscheForschungsgemeinschaft. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 251-263 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The antennae and their sense organs in nymphs and adult roaches of Gromphadorhina brunneri, were investigated and described. The number of segments and sensillae of the nymphal antennae depend on the developmental stage. Sexual dimorphism is pronounced. Males have longer antennae than females as well as an abundance of especially long sensory hairs (long wavy hairs), which are probably responsible for the perception of female sex pheromones. They also have more thin-walled sensory hairs, for instance, sensilla trichodea. On a morphological basis the sensillae of Gromphadorhina brunneri, were named and classified. Long wavy hairs and large sensory hairs appear to be present also in a related species, G. portentosa, but are lacking in others. Their distribution on the antennae varies greatly from that in G. portentosa but their structure varies only slightly. These two types of sense organs are considered to be specialized forms of sensilla chaetica. They are contact chemoreceptors, as are two other types of sensilla chaetica. Furthermore, thin-walled chemoreceptors are present, such as sensilla trichodea, sensilla basiconica, sensilla coeloconica and a typical mechanoreceptor, the sensillum campaniformium.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460206
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 74
    Electronic Resource
    Electronic Resource
    Cytological differentiation in the uropygial gland (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 395-413 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Ultrastructural changes were studied in the cells undergoing secretory differentiation in zone I of the tubules of the uropygial gland of White Plymouth Rock chickens. A layer of basal cells and four secretory stages are recognized as the cells migrate from the periphery to the lumen of tubules and progressively elaborate a secretion product.Basal cells, containing rough endoplasmic reticulum and free ribosomes, rest on the basement membrane and are the source from which secretory cells arise. Dilated perinuclear cisternae and the proliferation of smooth endoplasmic reticulum in the form of vesicles, invaginated sacs and cusp-shaped cisternae indicate the onset of lipogenesis in stage I cells. The perinuclear cisternae are more dilated and the endoplasmic reticulum is composed of saccules and cisternae in stage II cells. Stage III cells are characterized by concentric lamellae of endoplasmic reticulum surrounding secretory droplets. Dilated cisternae of endoplasmic reticulum and secretory droplets both contain a reticular substance. The perinuclear cisternae of stage III cells have returned to normal dimensions. Large mature lucent secretory droplets, lined with electron-dense material, fill the cytoplasm of stage IV cells which degenerate and release their secretory product into the tubule lumen.Spherical membrane-bound compartments containing a mottled substance of moderate electron density occur in basal cells and all subsequent secretory stages. These mottled bodies are surrounded by saccules of endoplasmic reticulum in stage II cells and are intimately associated with secretory droplets in stage III cells, but there is no evidence that they give rise to secretory droplets and their role in secretory differentiation is unknown.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460306
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 75
    Electronic Resource
    Electronic Resource
    Masthead (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975) 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460401
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 76
    Electronic Resource
    Electronic Resource
    The fine structure of the lateral ocellus of the dobsonfly larva (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 415-429 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The lateral ocelli of the dobsonfly (Protohermes grandis, Neuroptera) larva have been examined with light and electron microscopy. The larva has six ocelli on both sides of the head, each containing a single corneal lens. A conical crystalline body, of some 10-20 cells is situated immediately posterior to the lens. From 100 to 300 elongated retinular cells are arranged perpendicular to the crystalline body except at the innermost surface of the lens, where they are absent. The distal process of each retinular cell is enclosed by a tube-like rhabdom formed by the close association of microvilli from the same and adjacent distal processes. The distal process contains many mitochondria, multivesicular bodies, microtubles and pigment granules. In the dark-adapted ocellus the pigment granules are concentrated near the nucleus which lies under the rhabdomic layer. The granules diffuse toward the rhabdomic microvilli during light adaptation.Each retinular cell has a single axon, which extends from the ocellus as an ocellar nerve fiber into the optic lobe, where it frequently synapses upon second order neurons. In addition to these afferent synapses, there are two other synaptic combinations: (1) a feedback synapse from a second order neuron to a retinular axon, and (2) a synapse between second order neurons. These results suggest that photic signals reach the more proximal part of the brain via second order neurons after some degree of integration in the optic lobe.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460307
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 77
    Electronic Resource
    Electronic Resource
    The epithelium of the gastro-intestinal tract of Polypterus senegalus (Pisces:Brachiopterygii) (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 447-456 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Light and electron microscopic studies revealed ciliation of the epithelium of the entire gastro-intestinal tract of Polypterus. Acidophil cells were found in the different regions of the alimentary canal, including its derivatives (the lungs and hepato-pancreatic ducts). Compared to other primitive forms and modern teleosts, the extreme fusion of the intestinal caeca in Polypterus, the ciliation and the overall dispersion of acidophil cells may represent a special organization inherited from a palaeoniscoid ancestor. Attention is also drawn to a possible channel of early evolution and function of the stomach diverticulum.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460403
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 78
    Electronic Resource
    Electronic Resource
    Regeneration of digits and forelimbs in the Kenyan reed frog Hyperolius viridiflavus ferniqueiContribution number 52 from the Amphibian Facility.Supported in part by grants from the Muscular Dystrophy Associations of America and NIH Grant No. 1 PO6 RR 00572 to George W. Nace. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 431-445 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Newly metamorphosed individuals of the Kenyan reed frog, Hyperolius viridiflavus ferniquei, are able completely to regenerate amputated digits, including the morphologically complex digital pad. The sequence of morphological events is very similar to that seen in the typical epimorphic regeneration of amphibian extremities. Amputated forearms typically produce hypomorphic spike regenerates. Despite the lack of underlying hand and digital structures, an apical “digital” pad commonly differentiates.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460402
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 79
    Electronic Resource
    Electronic Resource
    The suspensorium of Ctenopoma acutirostre: A comparative functional analysis with Anabas testudineus (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 457-477 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The functional and structural aspects of the suspensorium of Ctenopoma acutirostre have been correlated with those of Anabas testudineus. The different parts of the suspensorium are described, as are the muscles that are functionally connected with the suspensorium. Functions were analyzed by observations on living specimens, and by measurements recorded from the movie films. The role played by various bones and muscles to carry out the functions (the respiration, the gulping, and the feeding) has been explained. The different bones and muscles have been considered as functional units which often are connected to form couplings. During the respiration in Ctenopoma the depression of the lower jaw is conducted by the levator operculiopercular apparatus-mandible coupling. The presence of this coupling is indicated by the presence of dorso-ventral movement of the operculum. A remarkable ventro-dorsal and antero-caudal movement in the urhyal during feeding shows in Ctenopoma the presence of the sternohyoideus-hyoid apparatus-interopercular-mandible coupling, which depresses the lower jaw. In Ctenopoma, the suspensorium takes part in respiration, gulping, and feeding, whereas in Anabas it is only involved in gulping and feeding. To carry out its functions, the suspensorium implies three articulations: palatocranial, craniohyomandibular, and quadratomandibular with the cranium and the lower jaw, respectively. Finally, the suspensorium has been analyzed as a part of the architectonic structure of the entire head by using a diagrammatic model (fig. 13) based on mutual influence, integration, and couplings.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460404
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 80
    Electronic Resource
    Electronic Resource
    Functional anatomy of the heart of the harbor porpoise, Phocaena phocaena (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 479-493 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Thirty-six harbor porpoises, Phocaena phocaena, were caught off the coast of Southern New Brunswick and Nova Scotia as part of a study of the biology and ecology of these animals. The formalin-preserved heart was examined first in situ, then measured and studied in detail. If the weight of the thick layer of blubber is discounted, the heart is heavy relative to the total body weight as may be expected in an animal capable of fast swimming, great agility and frequent emergence from the water to breathe. The shape of the heart, the relative size of atria and atrial appendages, the morphology of the ventricular septum, the thickness of the walls of the sinus and conus of the right ventricle and the anatomy of the pulmonary veins were found to be constant for this animal and unlike that of non-cetaceans. It is suggested that the absence of respiratory movements during diving may lead to these modifications of cardiac structure in an animal that is particularly well adapted to a totally aquatic existence.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460405
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 81
    Electronic Resource
    Electronic Resource
    The motor units of cat medial gastrocnemius: Electrical and mechanical properties as a function of muscle length (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 495-512 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The effects of changing muscle length on the mechanical properties of 89 motor units from adult cat medial gastrocnemius have been studied in eight experiments.Few differences were found between the effects of length on tetanic tension, twitch tension, twitch-tetanus ratio, twitch contraction time, twitch half relaxation time, rate of force development and electrical activity for fast contracting (twitch contraction time ≤ 45 msec) and slowly contracting ( 〉 45 msec) units. Those differences that did appear did not persist when these two groups were matched by tetanic tension. It is concluded that the biophysical mechanisms responsible for the changes in mechanical and electrical properties with length must be similar for fast and slow twitch units and not related to potential differences in their muscle fiber type.The effects of changing muscle length on the mechanical properties of the eight whole muscles suggest that changes in force output with length are of minor importance during normal movements as the muscle is found to be electrically active over a relatively narrow range of lengths close to the optimum length for tetanus of the whole muscle. The very shortest muscle lengths at which there is only minimal force development are not used in natural movements, while the declining limb of the length tension curve is at muscle lengths beyond the maximum in situ length.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460406
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 82
    Electronic Resource
    Electronic Resource
    Sensilla on the antennal flagellum of the sawyer beetles Monochamus notatus (Drury) and Monochamus scutellatus (Say) (Coleoptera: Cerambycidae) (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 513-531 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The antennae of the sawyer beetles Monochamus notatus and M. scutellatus were examined with the light and scanning electron microscopes to determine the types, number, distribution and innervation of the sense organs. Nine types of sensilla are described. Both short, thin-walled pegs (sensilla basiconica) and reversely curved thick-walled hairs (sensilla trichodea) are chemoreceptors. There are three types of long, thick-walled hairs (sensilla chaetica) which may be mechanoreceptors. One of these is modified in males to form unique snail-shaped pegs. A few dome-shaped organs, probably campaniform sensilla, were found.In addition to sense organs, many glands occur in association with the sensilla, and the antennae are well supplied with dermal glands connected by canals to small pores on the surface.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460407
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 83
    Electronic Resource
    Electronic Resource
    Masthead (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975) 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470101
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 84
    Electronic Resource
    Electronic Resource
    Epidermal downgrowths in regenerating rabbit ear holes (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 146 (1975), S. 533-542 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Rabbits are unique among mammals in that their ears can regenerate tissues from the margins of full thickness holes which grow in and completely fill the opening in about two months. The circular blastema that forms around the edges of the hole differentiates a new sheet of cartilage as it regenerates in a centripetal direction. Similar holes in other mammals fail to regenerate and form scar tissue instead of a blastema. Histological studies of the healing around the edges of rabbit ear holes reveal that during the second week, when the epidermis is completing its migration across the wound from the opposite sides of the ear, conspicuous tongues of epidermal cells grow down into the underlying tissues at the edges of the wound. These epidermal downgrowths are situated between the original intact dermis of the skin and the more central tissues which give rise to the blastema. Such downgrowths are of a transient nature, and are no longer found once the blastema rounds up toward the end of the second week. Since they are not found in the healing of similar wounds in rabbit ears prevented from regenerating by prior removal of their cartilaginous sheets, nor in the naturally nonregenerating ears of sheep and dogs, it is considered that these downgrowths of healing epidermis may play a role in the unusual regenerative response of ear tissues in the rabbit.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051460408
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 85
    Electronic Resource
    Electronic Resource
    The hyoid, laryngeal and pharyngeal regions of bathyergid and other selected rodents (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 229-250 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The morphology of the hyoid, laryngeal and pharyngeal regions of the following rodent genera was studied: Cryptomys, Bathyergus, Georychus, Heliophobius, Heterocephalus, Ctenomys, Petromus, Thryonomys, Geomys, Cannomys, and Tachyoryctes. A number of morphological conditions unique to bathyergids, and associated with the use of the head and lower incisors in burrowing are described. The conditions include the formation of functional complexes of MM. sterno-geniohyoideus and omo-mylohyoideus, the presence of a unique deep oblique part of M. transversus mandibulae and a strong separate slip of M. platysma myoides pars mentalis. The hyoid skeleton is modified to allow the muscle complexes to act independently of the basihyal bone, and to allow the unusually protrusible tongue to be withdrawn. The nerves of the jugular foramen do not form a true pharyngeal plexus, and their configuration is influenced by the absence of a well developed internal carotid artery in hystricognaths. The morphology of the regions studied indicates a natural grouping of bathyergids, but one in which Heterocephalus is somewhat separate from the remaining bathyergid genera. The grouping of bathyergids and New and Old World hystricognath rodents into a suborder Hystricognatha is supported.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470208
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 86
    Electronic Resource
    Electronic Resource
    Chelonian mental glands (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 275-291 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A survey of 69 of the 74 currently recognized chelonian genera revealed that 21 genera in three families (Emydidae, Platysternidae and Testudinidae) possess paired integumentary glands or gland vestiges in the anterior throat skin. These glands are here termed mental glands; they are holocrine and may be classified morphologically as follows: Class I mental glands are large, complex, multilobed, have specialized ducts, and are found only in the genus Gopherus: Class II mental glands are small, simple sacklike invaginations containing secretory cells or keratinizing cells. The structure of Class II glands varies from distinctive and saccular to shallow keratinized invaginations having no glandular tissue; they are found only in the families Platysternidae and Emydidae.Mental glands occur in 17 of the 22 genera in the subfamily Batagurinae (sensu McDowell, 64); only 2 of 9 genera in the subfamily Emydinae have these glands. The taxonomic occurrence of mental glands suggests that they are primitive structures. The loss of mental glands in most emydines is interpreted as a subfamilial trend toward integumentary simplification.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470303
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 87
    Electronic Resource
    Electronic Resource
    Scanning electron microscopy of the air bladder in the spotted gar, Lepisosteus occulatus (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 293-298 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The surface of the gar respiratory epithelium was examined by scanning electron microscopy. Nonciliated and ciliated cells constitute the epithelium. Puffs appear to be an unusual feature of the ciliated cells as well as nonciliated cells. There appears to be a transition from nonciliated to puff ciliated cells through a puff stage. The role of the cell types as related to oxygen available in the air bladder is discussed.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470304
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 88
    Electronic Resource
    Electronic Resource
    The formation and cytochemical characterization of cortical granules in ovarian oocytes of the golden hamster (Mesocricetus auratus)This investigation was supported by grants (HD06822 to E.A.; Training Grant 5T01 6M 00406; Center Grant HD06645) from the National Institutes of Health, the United States Public Health Service. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 251-274 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The formation and cytochemical characterization of cortical granules in the ovarian oocytes of the golden hamster have been investigated by use of light and electron microscopical techniques. Particular emphasis is given to the changing population of organelles associated with cortical granule formation. Our observations indicate that cortical granules are produced by the participation of both the Golgi complex and the rough endoplasmic reticulum. Ultrastructural cytochemistry reveals that the cortical granules are composed of glycoprotein. The cortical granules are released at fertilization by a merocrine-type of secretory process.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470302
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 89
    Electronic Resource
    Electronic Resource
    Techniques for estimating allometric equations (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 299-307 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Morphologists have long been aware that differential size relationships of variables can be of great value when studying shape. Allometric patterns have been the basis of many interpretations of adaptations, biomechanisms, and taxonomies. It is of importance that the parameters of the allometric equation be as accurate estimates as possible since they are so commonly used in such interpretations.Since the error term may come into the allometric relation either exponentially or additively, there are at least two methods of estimating the parameters of the allometric equation. That most commonly used assumes exponentiality of the error term, and operates by forming a linear function by a logarithmic transformation and then solving by the method of ordinary least squares. On the other hand, if the error term comes into the equation in an additive way, a nonlinear method may be used, searching the parameter space for those parameters which minimize the sum of squared residuals. Study of data on body weight and metabolism in birds explores the issues involved in discriminating between the two models by working through a specific example and shows that these two methods of estimation can yield highly different results. Not only minimizing the sum of squared residuals, but also the distribution and randomness of the residuals must be considered in determining which model more precisely estimates the parameters.In general there is no a priori way to tell which model will be best. Given the importance often attached to the parameter estimates, it may be well worth considerable effort to find which method of solution is appropriate for a given set of data.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470305
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 90
    Electronic Resource
    Electronic Resource
    Masthead (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975) 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470401
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 91
    Electronic Resource
    Electronic Resource
    A simplified placenta-like system for the transport of extraembryonic nutrients during embryogenesis of Bugula neritina (bryozoa)Contribution No. 17 from the Santa Catalina Marine Biological Laboratory. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 355-377 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Embryos of the marine cheilo-ctenostome bryozoan Bugula neritina undergo a marked increase in volume (about 500-fold) during embryogenesis while being retained in a brood chamber. Previous morphological studies indicate that shortly after transfer of the zygote to the brood chamber, the epithelium of the maternally-derived portion of the brood chamber, the ooecial vesicle, differentiates in regions adjacent to the embryonary space from a squamous to a columnar form suggesting that the parent is involved as a source of extraembryonic nutrients required for the extensive growth of the embryo.Results of the present ultrastructural study indicate that hypertrophy of the epithelial cells occurs only in that region of the ooecial vesicle which opposes the embryo, that differentiation (and subsequent regression) of the lining are predictable events correlated with the onset (and termination) of embryonic growth, and that hypertrophied cells are well equipped for the synthesis and transport of macromolecular materials across the vesicle wall to the developing embryo. Further, that portion of the embryo's ectoderm (the presumptive metasomal sac) in contact with this hypertrophied epithelium is morphologically specialized for the uptake of nutrients. Finally, shortly before release of the larva, this intimate association of the metasomal sac tissue and the hypertrophied ooecial vesicle lining epithelium is terminated by invagination of the sac and atrophy of the lining.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470308
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 92
    Electronic Resource
    Electronic Resource
    A gross and microscopic study of the respiratory anatomy of the antarctic weddell seal, Leptonychotes weddelli (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 309-335 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Four species of Phocidae, or true seals, inhabit the waters surrounding the Antarctic continent. These animals are thought to have different diving capabilities. The Weddell seal, Leptonychotes weddelli, is known to be capable of attaining depths up to 600 meters.The respiratory system of the Weddell seal shows the usual adaptations to an aquatic environment characteristic of other marine mammals. These include lungs that undergo compression collapse at depths greater than 70 meters; hyaline cartilage in the tracheo-bronchial tree as far as the terminal bronchioles; and large amounts of smooth muscle surrounding the distal-most bronchioles. The collapsible lungs provide a mechanism by which air is forced from the alveoli adjacent to the pulmonary capillary beds thereby preventing the absorption of nitrogen gas into the bloodstream. The presence of hyaline cartilage throughout most of the tracheo-bronchial tree increases the effective dead air space that accommodates most of the air forced from the collapsed lungs. The smooth muscle surrounding the respiratory bronchioles prevents their collapse while under the pressures of a deep dive. Collapse of the respiratory bronchioles not supported by cartilage would trap air in the lung alveoli during a dive.In addition, large-sac-like “diverticulae” are found in the submucosa throughout the tracheo-bronchial tree. These diverticulae, which open directly into the lumen of the tree, appear to be modified glands whose cells, in most cases, do not appear to be specialized for secretory function. They are most numerous in the more distal bronchi and terminal bronchioles where they are situated on both the luminal and adventitial sides of the hyaline cartilage supporting the walls of the air passages. Diverticulae are not found in the respiratory bronchioles or in the respiratory portion of the lungs.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470306
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 93
    Electronic Resource
    Electronic Resource
    An anatomical, histochemical, and autoradiographic study of the ever-growing molar dentition of Microtus with comments on the role of structure in growth and eruptionThe paper is a condensation of a thesis submitted in partial fulfillment of requirements for the degree of Master of Arts in Biology at Hofstra University.Reported in part at the annual meetings of the American Society of Mammalogists, Tampa, Florida, 1972 and Binghamton, New York, 1974. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 337-353 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: An analysis of the microanatomy of the molar dentition of Microtus utilizing histological, histochemical and autoradiographic techniques reveals a complex architecture with distinctive morphogenic mechanisms which respond to the functional requirements of the organism. These mechanisms include; the maintenance of continued growth and eruption of the molars to compensate for continued hard tissue loss from wear at the occlusal surface of the crown throughout the entire lifespan of the organism and a positive feedback repair mechanism to protect the growth systems from the potential destruction this normal occlusal wear could initiate. An awareness and understanding of these phenomena is of significant value for interpreting palentological specimens and formulating a theoretical model for interpreting the evolution of Microtine molar dentitions.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470307
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 94
    Electronic Resource
    Electronic Resource
    Assay of cyclic 3′-5′-monophosphate in the regenerating forelimb of the newt, TriturusSupported by grants from American Cancer Society, the National Institutes of Health, and the Multiple Sclerosis Society. (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 379-383 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The cyclic adenosine 3′-5′-monophosphate content of four regenerate stages in the forelimb of the newt, Triturus viridescens, was assayed using the Gilman method and compared to the content in the normal, unamputated, forelimb. The concentration was found to be highest in the earliest stages of regeneration, followed by a sharp drop and then a rise to a plateau approximately that of the unamputated limb. The possibility that cyclic AMP acts as a second messenger for nervous and hormonal influences on regeneration is discussed.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470402
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 95
    Electronic Resource
    Electronic Resource
    A study of the fine structure of the accessory muscle of the horseshoe crab, Tachypleus gigas (1975)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 147 (1975), S. 439-457 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The accessory muscle of the walking leg of the horseshoe crab, Tachypleus gigas, was examined electron microscopically. The muscle fibers vary in size but are small in diameter, when compared with other arthropod skeletal muscles. They are striated with A, I, Z and poorly defined H bands. The sarcomere length ranges from 3-10 μm with most sarcomeres in the range of about 6 μm. The myofilaments are arranged in lamellae in larger fibers and less well organized in the smaller ones. Each thick filament is surrounded by 9-12 thin filaments which overlap. The SR is sparse but well organized to form a fenestrated collar around the fibrils. Individual SR tubules are also seen among the myofibrils. Long transverse tubules extend inward from the sarcolemma to form dyads or triads with the SR at the A-I junction. Both dyads and triads coexist in a single muscle fiber, a feature believed to have evolutionary significance. The neuromuscular relationship is unique. In the region of synaptic contact, the sarcolemma is usually elevated to form a large club-shaped structure containing no myofilaments and few other organelles. The axons or axon terminals and glial elements penetrate deep into the club-shaped sarcoplasm and form synapses with the fiber. As many as 13 terminals have been observed within a single section. Synaptic vesicles of two types are found in the axon terminals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051470405
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 96
    Electronic Resource
    Electronic Resource
    Investigations on the turnover of adrenocortical mitochondria (1975)
    Springer
    Cell & tissue research 163 (1975), S. 273-290 
    Details
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Mitochondria ; Dexamethasone ; DNA-synthesis ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effects of chronic administration of dexamethasone (for up to 15 consecutive days) on both the morphology and DNA-synthesis of the mitochondria of the rat adrenal zona fasciculata were investigated by stereologic and autoradiographic techniques. Up to the 3rd day of continuous dexamethasone treatment, the average volume of mitochondria did not change, whereas the number of mitochondria per cell was significantly decreased. From the 3rd to the 15th day of hormonal administration both the volume and number of mitochondria were found to decrease in proportion to the duration of treatment. Autoradiography showed that after the 3rd day of dexamethasone administration there is virtually no incorporation of 3H-thymidine into the mitochondrial compartment. These findings are discussed in the light of evidence indicating that dexamethasone blocks ACTH-release by inhibiting the hypothalamo-hypophyseal axis. The results confirm the view that ACTH controls the maintenance of growth and proliferation of rat adrenocortical mitochondria.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219464
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 97
    Electronic Resource
    Electronic Resource
    The effect of cervical vagotomy (decentralization) on the ultrastructure of the carotid body of the duck, Anas platyrhynchos (1975)
    Springer
    Cell & tissue research 163 (1975), S. 491-502 
    Details
    ISSN: 1432-0878
    Keywords: Carotid body ; Duck ; Cervical vagotomy ; Innervation ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Carotid bodies of ducks show no detectable changes in ultrastructure up to periods of four weeks following the removal of 2–3 cm of the cervical vagus (decentralization). This indicates that the majority, and possibly all the nerves terminating on the glomus cells are afferent (sensory) in nature. These nerve endings are in reciprocal synaptic contact with the glomus cells and therefore have efferent and afferent functions. Theories concerning the carotid body receptor mechanism are discussed with particular reference to those theories which ascribe functions to the reciprocal synapses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218494
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 98
    Electronic Resource
    Electronic Resource
    Ultrastructure of pars nervosa and pars intermedia of the lamprey, Lampetra tridentata (1975)
    Springer
    Cell & tissue research 157 (1975), S. 165-184 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary gland, posterior ; Hypothalamo-hypophyseal system ; Cyclostomes ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pars intermedia of the adult lamprey is separated by perivascular spaces and a capillary plexus from the pars nervosa. No penetration of nerve fibers into the pars intermedia was found. The pars nervosa, which constitutes the posterior wall of the infundibulum, consists of an ependymal layer and a fuchsinophilic fiber layer; the latter contains at least four different types of axonal endings. The pars intermedia is avascular and is composed of a small proportion of non-secretory cells and a large proportion of secretory cells. The secretory granules in the cells of the pars intermedia seem to be discharged toward the capillaries that separate the pars intermedia from the pars nervosa. Although no direct nervous or vascular connections were found between the pars nervosa and pars intermedia, a mechanism of control of secretory activity in the pars intermedia cells by the central nervous system appears likely.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222064
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 99
    Electronic Resource
    Electronic Resource
    An investigation of the foetal rat spinal cord (1975)
    Springer
    Cell & tissue research 158 (1975), S. 241-249 
    Details
    ISSN: 1432-0878
    Keywords: Synapse development ; Spinal cord ; Foetal rat ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ultrastructural studies on the foetal rat spinal cord show that during synaptogenesis there is difficulty in recognizing true synaptic precursors. Asymmetric densities are found at unusual sites forming, for example, somato-dendritic and somato-somatic junctions. They are also found between neurons and possible glial processes. Symmetric densities occur between nerve cells but may be confused with desmosomes. Profiles exhibiting membrane density, cleft material and 50 nm vesicles, which are the most reliable indicators of presumptive synapses, are found between neurones, but also at junctions between neurones and what may be glial processes. The picture is further confused by the presence of degenerating axodendritic synapses at early foetal stages. Caution must be exercised in defining an apparent synapse or precursor in foetal cord as that of a presumptive functional synapse because of the observed degenerating profiles and because to our knowledge, somato-somatic, somatodendritic, and neurono-glial synapses have not been observed in adult cord. It is not known whether these structures are an unwanted consequence of development or play a role in guiding development.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219963
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 100
    Electronic Resource
    Electronic Resource
    Tubular structures associated with intracytoplasmic spirochetes (1975)
    Springer
    Cell & tissue research 158 (1975), S. 333-337 
    Details
    ISSN: 1432-0878
    Keywords: Spirochete ; Artemia ; Brine shrimp ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary When tissues of spirochete-infected brine shrimp (Artemia salina) were examined by electron microscopy, tubular structures were often seen closely associated with intracytoplasmic spirochete profiles. These tubules were never observed in association with spirochetes found in the haemocoel or other extracellular spaces. Since the trilaminar layer comprising the wall of the tubules was identical in ultrastructure to the outer envelope of the spirochete, these structures were interpreted to be finger-like extensions of the spirochete outer envelope.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00223830
    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...