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  • Articles: DFG German National Licenses  (141)
  • 1985-1989  (66)
  • 1975-1979  (75)
  • 1965-1969
  • 1986  (66)
  • 1975  (75)
  • Ultrastructure
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  • Articles: DFG German National Licenses  (141)
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Years
  • 1985-1989  (66)
  • 1975-1979  (75)
  • 1965-1969
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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    European archives of oto-rhino-laryngology and head & neck 243 (1986), S. 121-125 
    ISSN: 1434-4726
    Keywords: Bacterial labyrinthitis ; Ultrastructure ; Mycobacterium ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We used electron microscopy to investigate Mycobacterium fortuitum -induced changes in the inner ears of mice. We found that the inner and outer hair cells had degenerated and disappeared in the organ of Corti. Changes in the lower turn of the cochlea were more severe than those of the upper turn while the changes of the outer hair cells were more severe than those of the inner hair cells. Disappearance, fusion and ballooning of the sensory hairs were observed in the vestibular organs. The bacterial extract also induced inner ear damage which was similar to that caused by live M. fortuitum.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    European archives of oto-rhino-laryngology and head & neck 243 (1986), S. 260-264 
    ISSN: 1434-4726
    Keywords: Argyria ; Chemosensory function ; Oral Mucosa ; Ultrastructure ; X-ray microanalysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Generalized argyrosis can produce a number of abnormalities, including skin discoloration, liver and kidney dysfunction. We describe a patient with generalized argyrosis following long-term self-treatment with oral silver intake, in whom skin discoloration, progressive taste and smell disorders, vertigo and hypesthesia were observed. These findings were confirmed by chemosensory tests and electrophysiological investigations. The development of hypogeusia was assessed by subjective tests, while the progression of hyposmia was followed by recording olfactory evoked cortical potentials. Light and electron microscopy of tissue samplings demonstrated electron-dense mineral deposits in basal membranes, in macrophages, in the perineurium of peripheral nerves, along elastic and collagenous fibers, and in necrotic cells of the oral submucosa. Silver and sulfur deposits in affected tissues could be defined by X-ray microanalysis. The quantitative ratio between silver and sulfur in involved tissues was similar to that of an inorganic silver-sulfide (Ag2S) standard. The minute increase in the sulfur content when compared to the inorganic standard suggested a sulfur containing organic matrix of the tissue precipitates. Our findings indicate that the affinity of silver for membrane and neuronal structures and the deposition of silver as an insoluble compound (Ag2S) induce the progression of clinical disease.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-0584
    Keywords: Karyotype ; Bladder carcinoma ; Ultrastructure ; CSF ; Cell line
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The cell line 5637 which originated from a human urinary bladder carcinoma is known to produce GM-CSF and Multi-CSF ectopically. Determination of cell surface antigens defined by monoclonal antibodies was recently reported [6]. Here we report on the ultrastructure and karyology of this CSF secreting cell line. At the ultrastructural level the monolayer in vitro culture and the solid tumors formed in nude mice showed all characteristics consistent with a well-differentiated transitional cell carcinoma (TCC). A subclone was found to grow in suspension and did not secrete any CSF activity. High resolution chromsome analysis revealed chromosomal abnormalities which agreed only in few particulars with nonrandom chromosomal aberrations usually found in TCC. Analysis of the cytogenetic results showed that nearly all structural abnormalities present are known to be associated with acute or chronic human leukemia. The possibility that the ectopic production of CSF in this cell line may be correlated to one or more of the described chromosomal aberrations is discussed.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Archives of dermatological research 278 (1986), S. 398-406 
    ISSN: 1432-069X
    Keywords: Nevocytic nevi ; Congenital ; Ultrastructure ; Nevus cells ; Nerve contacts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary As only few previous investigations considered size-dependent differences in the histology of congenital nevocytic nevi (CNN) or focused on their ultrastructure, a light- and electron-microscopic study of six giant and six medium-sized CNN was performed. Histologically, giant CNN showed minimal junctional nevus elements and a pandermal, diffuse nevus cell extension including the subcutaneous tissue, while medium-sized CNN exhibited more abundant junctional nests and a rather focal pattern of nevus cell extension into the reticular dermis. Ultrastructurally, giant CNN often showed nevus cells with irregular and indented nuclei and also nevus cells with highly complicated dendrites. Nuclear inclusions, multiple cilia and centrioles, and collagen phagocytosis in nevus cells were found in both groups of CNN. Direct contacts between nevus cells and nerve fibers were observed in mediumsized CNN only. The findings provided no clear morphological indication why giant CNN have a higher risk for malignant degeneration than medium-sized CNN or acquired nevocytic nevi (ANN). On the other hand, the histological differences speak in favor of a different ontogenesis of the various size classes of CNN and ANN.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1432-2307
    Keywords: Epithelioid haemangioendothelioma ; IVBAT ; Immunohistochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Three patients with epithelioid haemangioendothelioma (EHE) are described. Two patients presented with pulmonary infiltrates and one with a hepatic tumour. All had a metastatic disease ending fatally, and all were autopsied. The diagnosis was confirmed either by immunohistological or ultrastructural analysis. All three tumours were cytokeratin-negative and vimentin-positive, while only two contained cells reacting with the antibody of factor VIII-related antigen. Electron microscopy of the third tumour revealed features indicating endothelial differentation. A short literature review is also presented demonstrating that the outlook of EHE is worse than previously thought.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1432-2307
    Keywords: Mesothelioma ; Serous membrane ; Localized tumour ; Histogenesis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary It is uncertain whether localized lesions of serosal membranes have a kinship to mesotheliomas or are truly fibromatous in nature. Ultrastructural and immunohistochemical investigations were carried out on 12 localized benign and malignant pleural and peritoneal tumours from 10 patients. Electron microscopic findings, including the consistent and non-fibroblastic cellular organization of localized neoplasms, the presence of some form of intercellular junctions in 7 of 10 cases, basal lamina deposition in 3 cases, and polarized microvilli in one case indicated a form of mesothelial differentiation. Using monoclonal and polyclonal antibodies, positive immunostaining of tumour cells for cytokeratin peptides was detected in one case, while antibody to vimentin stained four cases. Light microscopic, ultrastructural and immunohistochemical features of one benign localized serosal tumour, with a unique blend of epithelial and spindle cells, provided further evidence for a histogenic link between localized serosal tumours and diffuse epithelial mesotheliomas. On the basis of the current findings and reports in the literature, it would appear that the majority of localized tumours of serosal membranes are a subset of mesothelioma, while a minority are fibromas.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 410 (1986), S. 43-48 
    ISSN: 1432-2307
    Keywords: Endocarditis ; Staphylococcus ; Colonisation ; Morphology ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The initial colonization, byStaphylococcus aureus, of the catheter damaged aortic valve and aorta of the rabbit, was examined by light and electron microscopy at 15 min, 3 h and 24 h post inoculation (PI). At 15 min PI, the majority of bacteria (80%) were located on the lateral surfaces of the thrombic vegetations while 20% were attached directly to the connective tissue of the aortic valve and aorta in areas where the endothelial lining was disrupted. By 3 h the bacteria on the thrombic vegetations were covered by fibrin. At this time, the bacteria both within the vegetations and on the surface of the vasculature were undergoing multiplication to form small groups. The precipitation of thrombus around the bacteria attached to the surface of the aorta to form microscopic infected vegetations had occurred by 24 h PI. The colonizing bacteria did not elicit any phagocytic response. The colonization of the cardiovasculature byStaph. aureus did not necessarily require pre-existing vegetations.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 1432-2307
    Keywords: Human acute pancreatitis ; Enzyme immunocytochemistry ; Ultrastructure ; Acinar cell degranulation ; Fat necrosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Human acute pancreatitis results from an autodigestive process frequently associated with alcohol abuse, gall stone disease and shock. Peripancreatic fat necrosis was identified as one of the earliest visible lesions, whereas acinar cell necrosis and haemorrhage were regarded as secondary changes. To examine the alterations in acinar cells in more detail, their enzyme content and fine structural features were studied immunocytochemically using antisera against α-amylase, lipase, trypsin, chymotrypsin and pancreatic stone protein, and electronmicroscopically in pancreatic tissues from patients with severe acute pancreatitis. Peripheral acinar cells in the immediate vicinity of fat necrosis were found to be heavily degranulated, while acinar cells at some distance of necrosis fully retained their enzyme content. Other frequent changes of the acinar cells included cuboidal transformation, loss of microvilli, increased occurrence of autophagosomes, and formation of enlarged acinar lumina. As there was no apparent cell membrane leakage or rupture of duct lumina, it is concluded that the acinar cells adjacent to fat necrosis release their granules by undirected basolateral extrusion. The findings thus suggest that one of the basic defects in acute pancreatitis is the uncontrolled release of enzymes from peripheral acinar cells into the interstitial space which, in turn, presumably by the action of lipase, leads to autodigestive fat necrosis.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1434-0879
    Keywords: Monkey spermatozoa ; Gossypol effect ; In vivo examination ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The present study examines the ultrastructure of ejaculated spermatoza from bonnet monkey, Macaca radiata under noraml conditions, with gossypol treatment and during recovery from such treatment. Monkeys were fed orally with gossypol acetic acid (GAA) for 3 months (4 mg/monkey/5 days a weak). Semen samples collected by electroejaculation, and the spermatozoa were examined using both light and electron microscopy. The degree of motility was also noted by Kalla et al. [12]. Ejaculated spermatoza were immotile 90 days after GAA treatment, but little evidence for any abnormality in the spermatozoa could be seen by light microscopy. Some ultrastructural changes were observed, but not to the extent previously reported in spermatozoa of Macaca fascicularis [23]. After termination of treatment, semen samples were obtained every 5th day until sperm count and motility recovered to the normal level. After 90 days only a small proportion of spermatozoa showed abnormal structure. We conclude that in a subhuman animal model gossypol induced effects on sperm motility and morphology are reversible.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 173 (1986), S. 295-298 
    ISSN: 1432-0568
    Keywords: Cardiodilatin ; Peptide Hormone ; Heart ; Human ; Immunohistochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The immunogold technique was applied to detect cardiodilatin-immunoreactivity (CDD-IR) in human heart. Using antibodies directed against C-terminal regions of CDD, we could identify colloidal gold label in specific atrial granules of human heart. The granules in all areas of the myoendocrine cells were homogeneously labelled and all right atrial biopsy specimen of patients with different heart diseases reacted positively and had the same distribution of label. The Golgi-apparatus and ergastoplasma exhibited and extremely weak CDD-IR. The results indicate a predominant storage of CDD in specific granules.
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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 173 (1986), S. 361-370 
    ISSN: 1432-0568
    Keywords: Electrical synapses ; Chemical synapses ; Ultrastructure ; Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Thin sectioning and freeze-fracturing have revealed the distribution of gap junctions and chemical synapses in the synaptic interface of the large myelinated club endings on the lateral dendrite of the goldfish Mauthner cell. In 12 samples of club endings fractured completely or nearly completely, the apposed synaptic membrane area averaged 39.090 μm2, of which 16.6% was occupied by gap junctions and about 4 to 5% by the active zones of chemical synapses. The numerical profile density (number per unit area of the synaptic membrane) of gap junctions varied greatly, from 1.78 to 6.30, and was mostly in inverse proportion to their size. The chemical synapses were located mainly in two places: in the circumferential rim of the synaptic membrane next to the widened extracellular space, and in the margins of intraterminal invaginations of the synaptic cleft. The axoplasm of the preterminal axon, just after losing its myelin sheath, was filled with microtubules, among which neurofilaments gathered into many small bundles. The correlation between the areas of gap junctions and the chemical synapses and the amplitude of the excitatory postsynaptic potentials (EPSP) is discussed.
    Type of Medium: Electronic Resource
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  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 173 (1986), S. 385-391 
    ISSN: 1432-0568
    Keywords: Elastic cartilage ; Chondrogenesis ; External ear ; Rat ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Selected ultrastructural features of chondrocytes and the extracellular matrix in the developing elastic cartilage of the external ear were studied in rat fetuses and young animals. The cytoplasmic lipid droplets were first observed in the 19-day fetus. They increase in number and size during the first post-natal week. The elastogenesis proceeds in the sequence: oxytalan fibers (17-day fetus), elaunin fibers (1-day rat), elastic fibers (5-day rat). Intermediary stages between the randomly oriented individual microfibrils and bundles of microfibrils (oxytalan fibers) were also observed.
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  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 174 (1986), S. 27-33 
    ISSN: 1432-0568
    Keywords: Cerebral cortex ; Antisera ; Biopsy ; Postmortem Alzheimer's type dementia ; Ultrastructure ; Epilepsy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary NPY-containing neuronal structures in the cereoral cortex of surgical tissue samples were compared to those in postmortem material by immunocytochemical methods. However, the quality of preservation of individual neurons and axonal and dendritic plexuses in the neuropil is unusually fine in the surgical specimens. This result is most likely attributable to the excellent fixation that can be regularly achieved by rapid and careful handling of tissue during and after surgical removal. The tissue is suitable for both light and electron microscopy, and the superior preservation also leads to intense, reliable antibody reactions. Postmortem tissue samples can provide good specimens for immunocytochemistry when properly handled as previously described. However the postmortem delays prior to fixation disrupt neuronal integrity in the immunostained structures. Nevertheless, postmortem material from carefully studied subjects of neurological diseases compared with age matched controls can provide valuable information.
    Type of Medium: Electronic Resource
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  • 14
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 173 (1986), S. 317-322 
    ISSN: 1432-0568
    Keywords: Paneth cell ; Ultrastructure ; Morphometry ; Germfree rats ; Ex-germfree rats
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Ultrastructural changes of Paneth cells of germfree (Gf) rats which had been inoculated with bacteria-containing feces from conventionally-reared (SPF) rats were quantitatively examined. 12 and 24 h after inoculation, the Paneth cells showed a striking decrease in the number of secretory granules and the occurrence of large vacuoles. Phagosomes containing bacteria were not seen. After 4 days, the secretory granules reaccumulated and smooth-surfaced apical vesicles increased in number. It is discussed that the large vacuoles may be related to membrane-retrieval events following the massive extrusion of secretory granules whereas the apical vesicles appear to serve this function when exocytosis is not pronounced. In addition to the large secretory granules ca. 10% of Paneth cell profiles contained a few dense-cored vesicles measuring about 150 nm in diameter which resemble peptidergic neurosecretory granules.
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  • 15
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 71 (1986), S. 83-87 
    ISSN: 1432-0533
    Keywords: Astrocytes ; Brain neoplasms ; Oligodendroglioma ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Ultrastructural concentric laminations have previously been thought to be specific to oligodendroglioma. However, these structures were also recognized in fibrillary astrocytomas, a mixed glioma and a glioblastoma. These laminations continued or closely related to attenuated processes or cytoplasm of astrocytic tumor cells. In addition, some lamellae contained glial filaments. It is considered that the concentric laminations are derived from attenuated astrocytic processes and have no relationship with myelin.
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  • 16
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 70 (1986), S. 44-52 
    ISSN: 1432-0533
    Keywords: Gliosarcoma ; Myxoid tumor ; Extracranial metastasis ; Ultrastructure ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The case of a 22-year-old female suffering from glioblastoma with sarcomatous component (WHO; gliosarcoma) is presented. The tumor consisted of glioblastomatous and sarcomatouos components, and in part of the pleomorphic astrocytomatous region of the glioblastoma there was a prominent production of myxoid matrix. On the basis of its histochemical and immunohistochemical characteristics, the present case strongly suggested that glial cells of neuroectodermal origin assume part of the responsibility for production of myxoid material.
    Type of Medium: Electronic Resource
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  • 17
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 72 (1986), S. 134-141 
    ISSN: 1432-0533
    Keywords: Cerebral embolism ; Fungal vasculitis ; Paecilomyces javanicus ; Prosthetic valve endocarditis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A 41-year-old diabetic woman developed Paecilomyces javanicus endocarditis and subsequent cerebral fungal embolism and vasculitis with massive infarction and hemorrhage 6 years after a mitral valve replacement with porcine heterograft. The organism was identified by the culture from the infected brain tissue and aortic valve. Cerebral infection due to fungus Paecilomyces is rare. This report documents the cerebral manifestations of fungus Paecilomyces javanicus and describes for the first time the ultrastructure of such an organism obtained from the infected tissue. Their ultrastructural findings, similar to those described in Paecilomyces farinosus derived from culture, include a double-layered cell wall, a triple unit plasma membrane, abundant cytoplasmic lipid droplets, vacuoles, membranous profiles and septal formation. This report further demonstrates hyphae with packed 50A filaments and granulofibrillary material and features suggestive of intrahyphal hyphae, not previously described in fungus Paecilomyces.
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  • 18
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 70 (1986), S. 127-134 
    ISSN: 1432-0533
    Keywords: Avian muscle spindle ; Denervation ; Intrafusal fiber ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The role of the nerve in maintaining the ultrastructural integrity of avian muscle spindles was investigated by denervating the pigcon's extensor digitorum communis for periods of 10, 19, and 28 days. The equatorial region of control intrafusal fibers had a reduced density of myofilaments. Sensory endings contained mitochondria and structures resembling synaptic vesicles, and were associated with satellite cells. In the polar region, fibers had a high concentration of myofilaments; small motor endings, unlike sensory endings, lay outside of the fiber's basal lamina. The outer capsule consisted of thin, tightly layered cells which gradually became reduced in number distal to the equatorial region. In both equatorial and polar regions the capsule became more disrupted with longer denervation periods, and lysosomes and phagocytes became more abundant. The equatorial region of denervated fibers contained many myofibrils and some had peripherally-located nuclei, unlike the controls; sensory terminals were absent. The polar region of some fibers had disorganized myofilaments and others had a reduced myofilament density. Fiber diameters increased significantly in both regions. Thus, denervated intrafusal fibers lost some characteristics which distinguish them from extrafusal fibers.
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  • 19
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 70 (1986), S. 71-74 
    ISSN: 1432-0533
    Keywords: 6-Aminonicotinamide ; Ependymal cell ; Mitosis ; Suckling mice ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Mitotic ependymal cells were encountered in 10-day-old mice treated with 6-aminonicotinamide, an antagonist of niacin. These occurred along the medial surface of the lateral ventricle and the ventral portion of the aqueduct. Electron microscopy revealed that both mitotic ependymal cells had eccentrically placed chromosomes without a nuclear membrane and well-formed gap junctions in contact with adjacent ependymal cells. Microtubules from a centriole radiated to the chromosomes. These data show that cell division occurs in morphologically matured ependymal cells in the postnatal brain under pathological conditions. We believe this to be the first ultrastructural demonstration of this phenomenon.
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  • 20
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 174 (1986), S. 379-389 
    ISSN: 1432-0568
    Keywords: Lungs ; Amphibia ; Ultrastructure ; Morphometry ; Surfactant
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Lungs ofHyla arborea L. were examined by scanning and transmission electron microscopy and morphometric methods. The lungs contain several interconnected folds in a netlike reticular arrangement of first, second and third order, mainly covered with pneumocytes. On the septa of first and second order, irregularly distributed small patches of ciliated epithelium devoid of goblet cells are located. Dome-shaped neuroepithelial bodies can be seen in the vicinity of ciliated epithelium. The pulmonary epithelium consists of one type of pneumocyte, which contain in their cytoplasm three kinds of bodies: lamellar, dense and multivesicular. The dense bodies are precursors of lamellar bodies (LBs), while the multivesicular bodies are incorporated into the LBs, being later secreted to the air space. The lining layer covering the internal lung surface contains numerous transformed LBs but tubular myelin figures are scarce. The surface of the lining layer is coated by a thin film. The air-blood barrier, consisting of three layers: epithelium, interstitial space and endothelium, is 0.6 μm thick.
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  • 21
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 69 (1986), S. 81-90 
    ISSN: 1432-0533
    Keywords: Creutzfeldt-Jacob disease ; Slow virus infection ; Subacute spongiform encephalopathy ; Ultrastructure ; Synapse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Guinea pigs inoculated with brain homogenate from serially passaged Creutzfeldt-Jakob disease (CJD) were killed biweekly starting at week 2 until terminal illness (about 200 days following inoculation). A mild swelling of postsynaptic dendrites and an increase in the number of glial filaments in astrocytic processes was seen at week 4, followed by increased swelling and lucency of axons and dendrites by week 6 post inoculation (p.i.). Severe undulation and focal interruptions of synaptic membranes were also observed both at weeks 4 and 6. By week 8, one could see cystically dilated cellular processes. These sometimes showed continuity with adjacent swollen processes through focally disrupted plasma membranes, and most likely represent a progressive enlargement of vacuoles through fusion and subsequent addition of adjoining processes. The spongiform changes increased mildly between week 8 and week 10 and remained essentially the same in subsequent weeks. After week 24 there was a sharp increase in both the number and size of vacuoles. At week 24 severe structural alterations were present both in the neurons and astrocytes, and numerous intranuclear inclusions were demonstrated in many neuronal nuclei. This study shows that morphological changes in the brain occur considerably earlier than the clinical manifestations of the disease. In the early phase of the disease, there were significant alterations on the dendrites and synapses.
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  • 22
    ISSN: 1432-0533
    Keywords: Streptozotocin-diabetic rat ; Myenteric plexus ; VIP-ergic nerves ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Enteric nerves in the ileum of rats 8 weeks after streptozotocin-induction of diabetes were examined under the electron microscope before and after immunolabeling for vasoactive intestinal polypeptide (VIP). These studies have provided evidence of degenerative changes in the myenteric nerve fibres of diabetic rats, many of which were shown to contain VIP. It is suggested that VIP-ergic nerves in the gut may play a role in the developent of gastrointestinal dysfunction in diabetes.
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  • 23
    ISSN: 1432-0533
    Keywords: Brain tumor ; Rhabdomyosarcoma ; Immunohistochemistry ; Ultrastructure ; Cerebral paragonimiasis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A necropsy case of a primary rhabdomyosarcoma with chronic paragonimiasis in the cerebrum of a 68-year-old man is reported. The clinical data showed a right hemiplegia and dysarthria which became lethal in 6 months even though operation and radiation therapy were performed. Computed tomography revealed a large low-density area associated with the peripheral enhancement in the left basal ganglia, and multiple conglomerated calcified masses in the left temporal and occipital lobes. Biopsied and necropsied materials of the tumor in the basal ganglia was reddish brown in color and histologically was composed of purely mesenchymal derivatives with both embryonal and mature striated muscle cells but neither neuronal nor glial elements. Some of the tumor cells with extending slender cytoplasms showed obvious cross striations at the light and electron microscope levels and immunohistochemical reactivity for myoglobin. All tumor cells were also positive for vimentin, but not for glial fibrillary acidic protein. The clinical and necropsy findings revealed no primary lesion anywhere but in the brain. In addition, numerous dead oval eggs ofParagonimus westermani were found in many cystoid lesions encapsulated by thick connective tissues with calcification and/or ossification. Clinicopathological features of 24 cases of primary rhabdomyosarcoma of the central nervous system reported in the literature are reviewed briefly. The histogenesis of this tumor are discussed together with comments on cerebral paragonimiasis.
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  • 24
    Electronic Resource
    Electronic Resource
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    Archives of dermatological research 279 (1986), S. 77-82 
    ISSN: 1432-069X
    Keywords: Lichen nitidus ; Lichen plahus ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Lichen nitidus (LN) and lichen planus (LP) are considered by some investigators to be two variants of the same disease, and by others to be two distinct dermatoses. In order to obtain further information about the relationship between LN and LP we examined the ultrastructure of lesions from two LN patients. In the central part of the lesion, the basement membrane was absent, or was interrupted by migrating phagocytes or lymphocytes. The basal cells and the lower cells of the stratum spinosum exhibited karyolysis and appeared to be compressed and often necrotic. In the upper dermis irregular cell debris full of clumps of tonofilaments and colloid-body-like structures was observed. A dense dermal infiltrate of macrophages, lymphocytes, fibrocytes, and Sezary-like cells was present. Signs of cooperation between lymphocytes and macrophages were also evident. The periphery of the lesion showed no pathological features except for enlargement of the intercellular spaces and the presence of mononuclear cells scattered through the epidermis. Several normal Langerhans cells were noticed. These ultrastructural findings were quite similar to those reported for LP.
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  • 25
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 42 (1986), S. 144-147 
    ISSN: 1420-9071
    Keywords: Ultrastructure ; catalase ; D-amino acid oxidase ; fetal mouse liver ; hepatocytes ; peroxisomes ; muscular dysgenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the hepatocytes of ‘normal’ fetal mice from mothers which were carriers of muscular dysgenesis, catalase and D-amino acid oxidase (DAAO) positive as well as negative peroxisomes were observed. DAAO reaction product was occasionally localized in patches around cell membranes and DAAO-positive peroxisomes were frequently observed near mitochondria.
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  • 26
    ISSN: 1432-1106
    Keywords: Optic tectum ; Neurotransmitters ; Cholinergic markers ; Ultrastructure ; Goldfish
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Neurochemical parameters associated with cholinergic and excitatory amino acid transmission, were measured in synaptosomes of the goldfish optic tectum at different times after unilateral eye ablation. Significant decreases in choline acetyltransferase and acetylcholinesterase were measured 12 and 30 days after enucleation. The high affinity choline uptake did not parallel the decrease in cholinergic enzymes. Instead there was a significant increase of the uptake per unit of protein (though not relative to the total number of tectal synaptosomes). No decrease of the high affinity D-3H aspartate uptake was measured in the deafferentated optic tectum. Electron microscopic observations showed a correspondence between the time course of cholinergic enzyme decrease and the degeneration of retinal afferents to the tectum. The present results support the notion that acetylcholine is a better candidate than the excitatory amino acids for a neurotransmitter role in the fish optic tectum.
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  • 27
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    European journal of pediatrics 144 (1986), S. 557-562 
    ISSN: 1432-1076
    Keywords: Rimmed vacuoles ; Childhood ; Myopathy ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A 5-year-old boy suffered from a slowly progressive non-familial neuromuscular disease, clinically marked by generalised muscle weakness, atrophy and hypotonia, a “myopathic” EMG and mildly elevated CK values. His gastrocnemius muscle showed marked myopathy, type I fibre predominance, and numerous “rimmed” vacuoles. This boy's condition is regarded as a childhood neuromuscular disease with rimmed vacuoles.
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  • 28
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    Child's nervous system 2 (1986), S. 297-300 
    ISSN: 1433-0350
    Keywords: Pineocytoma ; Magnetic resonance imaging ; Computed tomography ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The radiological and pathological findings in three children with pineocytomas are described. The patients presented with symptoms and signs of increased intracranial pressure. CT scans demonstrated obstructive hydrocephalus, but failed to visualize pineal masses that were subsequently seen on MR scans. A suboccipital, supracerebellar approach was used to obtain tissue for histological diagnosis and, in one case, achieve a total removal. Light microscopy demonstrated typical pineocytomatous rosettes without evidence of gangliocytic or astrocytic differentiation. Electron microscopy revealed numerous dense core vesicles with synaptic ribbons, suggesting neurosecretory capability. These three cases demonstrate the diagnostic advantage of MR imaging for tumors in the pineal region as well as the relatively well-differentiated histopathological characteristics of pineocytomas.
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  • 29
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    Virchows Archiv 409 (1986), S. 163-169 
    ISSN: 1432-2307
    Keywords: Thymoma ; Thymic carcinoma ; Ultrastructure ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A case of thymic carcinoma arising within a lymphocyte rich thymoma is reported. The undifferentiated carcinoma contained cellular elements resembling choriocarcinoma but could be differentiated there-from by positive staining for prekeratin antigen and an absence of staining for B-HCG antigen utilizing immunohistochemical techniques.
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  • 30
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    Theoretical and applied genetics 72 (1986), S. 840-844 
    ISSN: 1432-2242
    Keywords: Chlorophytum comosum ; First pollen mitosis ; Male plastid inheritance ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The behaviour of plastids and mitochondria during the formation and development of the male gametophyte of Chlorophytum comosum has been investigated using electron microscopy. During first pollen mitosis an intracellular polarization of plastids occurs in that the plastids are clustered in the centre of the microspore. The originating generative cell normally lacks plastids. Only in a small number of microspores have plastids been observed near the dividing nucleus of the microspore and later on in the generative cell. These observations agree with the genetic investigations of Collins (1922) on the mode of plastid inheritance which demonstrated a small amount of biparental plastid inheritance in Chlorophytum. The cytological mechanisms underlying plastid polarization during the first pollen mitosis are discussed.
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  • 31
    ISSN: 1432-0878
    Keywords: Glucocorticoids ; Cartilage ; Growth ; Histochemistry ; Ultrastructure ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effects of different doses of various steroids on growth, and on costal and epiphyseal chondrocytes, have been studied in prenatal, immature, and adult Long-Evans rats using histochemical techniques, and both light and electron microscopy. Both prenatal and postnatal treatments have been employed. The steroids used were cortisone (CA), betamethasome (BM), and, in the prenatal group only, dexamethasone (DM). Body weight is reduced in all treated rats (except the low dose of CA) by day 17 of gestation, with greater weight reductions occurring in rats receiving the higher dose level of each steroid. In rats treated prenatally or neonatally, and sacrificed postnatally on days 39–43 or days 116–127, body weights, and tibial and tail lengths, are less than in correspondingly aged controls, thus showing a persistence of the effects of treatment. Costal and epiphyseal cartilages in prenatal rats show cellular, synthetic, and ultrastructural alterations induced by treatment with glucocorticoids but the responses are not necessarily comparable. Except for the low dose of DM, the higher doses of each steroid are more effective in inhibiting, or altering, growth and cellular differentiation in the developing fetuses. Surprisingly, a low dose of DM has a more devastating effect on the cells and extracellular matrix of both costal and epiphyseal cartilage, than do higher dose-levels of the various steroids. Low doses of CA and BM are also effective in inhibiting or altering growth and cellular differentiation, but their effectiveness is largely limited to 17 days of gestation. The order of effect of the various doses of the different steroids on fetal cartilage, listed in decreasing order of severity, is as follows: 0.12 DM, 0.24 DM, 0.42 BM, 50 CA, with 25 CA and 0.18 BM being approximately equal and only slightly different from control cartilages. The effect of prenatal or neonatal glucocorticoid treatment on chondrocytes is minimal in the 30–43 day, or 116–127 day, postnatal groups. In immature and adult rats, cortisone affects the chondrocytes more deleteriously than does betamethasone, and a 5.0 mg dose of CA seems to affect chondrocytes, body weight, and tibial and tail lengths more than 0.2 or 7.5 mg doses.
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  • 32
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    Cell & tissue research 244 (1986), S. 457-466 
    ISSN: 1432-0878
    Keywords: Microthrix ; Microvillus ; Ultrastructure ; Fixation ; Tapeworm ; Hymenolepis diminuta
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of microtriches of the rat tapeworm, Hymenolepis diminuta, was examined with a number of electron-microscopic techniques. Fixatives containing different buffers, non-ionic detergents, chelators, tannic acid and various concentrations of aldehydes were tested for ability to stabilize cytoskeletal components while extracting background material. These methods revealed features unique to these specialized microvilli, and permitted construction of a detailed model of microthrix architecture. The microtriches of H. diminuta are comprised of a microfilament-containing base, a dense cap and a complex junctional region between the base and cap. The microfilaments of the base are contiguous distally with a tubular structure (the junctional tubule) within the junctional region; proximally, the microfilaments end abruptly: a terminal web appears to be absent. A beveled bilayered cylinder of dense material (the core tunic) encircles the microfilamentous core. The core tunics and junctional tubules of the microtriches are specifically and uniformly aligned along the strobila. Microtriches therefore can be distinguished from other microvilli (e.g., those of enterocyte brush borders) by their complex ultrastructure and precise orientation upon the cytoplasmic surface.
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  • 33
    ISSN: 1432-0878
    Keywords: Duodenum ; Cholecystokinin ; Gastrin ; Immunocytochemistry ; Ultrastructure ; Man
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Human duodenal endocrine cells reactive with antibodies to cholecystokinin (CCK) 33 (10–20) and/or gastrin 34 (1–15) were studied by a combination of immunohistochemical and electron-microscopic methods. By immunohistochemistry, three types of endocrine cells were distinguished in human duodenal mucosa, i.e., those only positive for only CCK, those positive for both CCK and gastrin and those only positive for only gastrin. Ultrastructurally, the first cell type is characterized by many secretory granules with an eccentric dense core (mean diameter; 271+-74 nm). The second cell type, which was less frequent than the other two, has ultrastructural features that resemble type-I cells. The last cell type was composed of two types of cells containing small secretory granules identical to those of IG cells (mean diameter; 171+-31 nm) or large secretory granules indistinguishable from those of I cells (mean diameter; 286+-50 nm).
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  • 34
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    Cell & tissue research 246 (1986), S. 39-44 
    ISSN: 1432-0878
    Keywords: Ultimobranchial glands ; Cysts ; C-cells ; Ultrastructure ; Chicken (Gallus gallus)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultimobranchial glands of the chicken were examined by electron microscopy and immunocytochemistry using a calcitonin antiserum. Electron microscopy confirmed the presence of C-cells, containing numerous secretory granules storing calcitonin, in the luminal lining of cyst-like structures found in these glands. These cells were furnished with prominent microvillar projections at their luminal surface, and the cytoplasm of the apical region was filled with fibril material. Furthermore, the cells contained prominent junctional complexes and desmosomes at their apico-lateral surfaces. In these C-cells, secretory granules were concentrated near the lumen and some were attached to the apical cell membrane. The luminal content of the cysts had a colloid-like and flocculent appearance, and was frequently seen attached to the cytoplasmic projections or apical cell membrane of the C-cells. Since the cysts progressively increase in volume and number with age, it is suggested that they may partly play a role in the storage of excess or unneeded hormonal products.
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  • 35
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    Cell & tissue research 245 (1986), S. 91-100 
    ISSN: 1432-0878
    Keywords: Testis ; Leydig cells ; Crystalloids ; Ultrastructure ; Rat, Rattus fusdpes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of Leydig cells in a seasonally breeding rodent, Rattus fuscipes, was studied in the breeding and non-breeding season and compared with Leydig cell morphology after suppression of gonadotrophin secretion induced by hypophysectomy or chronic administration of testosterone. Serum luteinizing hormone (LH) and testosterone (T) were measured and in-vitro T production by testes was assessed by stimulation with human chorionic gonadotrophin (hCG). In non-breeding wild-trapped rats and rats with experimental suppression of gonadotrophins, the Leydig cells were atrophied and exhibited variable amounts of cytoplasmic lipid and crystalloid inclusions, the latter commonly dominating the cytoplasmic area. Compared with fertile rats, serum LH and hCG-stimulated T production of experimentally regressed rats was significantly reduced, confirming structural features indicative of Leydig cell inactivity. Atrophy of Leydig cell nuclei was accompanied by the formation of unusual intranuclear vesicles sometimes containing small crystalloids. Ultrastructural analysis suggested transfer of the vesicles to the cytoplasm where their unification gave rise to much larger crystalloid bodies. Crystalloids occurred when serum LH was depressed and with either full (T treatment) or arrested spermatogenesis (hypophysectomy) suggesting that their formation is governed by pituitary function and is not dependent upon the degree of spermatogenic activity.
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  • 36
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    Cell & tissue research 246 (1986), S. 607-621 
    ISSN: 1432-0878
    Keywords: Rod photoreceptor ; Light damage ; Albino rat ; Ultrastructure ; Reversible change
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The temporal sequence of ultrastructural changes induced in the rat rod photoreceptor by 80 lux light-stress has been studied. The changes seen were compared with those produced by a much dimmer (3 lux) illumination. Some of the early signs of abnormality were (1) degradation of some disk membranes at the tips of outer segments, (2) disaggregation and detachment of ribosomes, (3) lighter matrices in swollen mitochondria, (4) disappearance of the Golgi apparatus, (5) proliferation of autophagic bodies in the inner segments, and (6) appearance of perimitochondrial membrane whorls in the synaptic terminals. No single change could be identified that would inexorably lead to cell death. The overall picture, however, suggested that an inability of the cell to maintain its anabolic balance is responsible for the pyknosis that occurs when the 80 lux exposure exceeds 12–15 h. All changes were reversible when exposure duration did not exceed 12 h, the normal length of the light cycle for these rats.
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  • 37
    ISSN: 1432-0878
    Keywords: Smooth-muscle cell ; Cell culture ; Ultrastructure ; Optical measurement ; Cell contraction ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In numerous investigations using cultured smooth-muscle cells, investigators have consistently added 10–20% fetal calf serum (FCS) to the medium to maintain viable cells. In the present study we utilized an optical technique to investigate whether smooth-muscle cells, cultured with or without FCS, maintain their contractile activity in vitro. With such optical measurement, we were able to detect signals due to spontaneous contractions, in muscle cells cultured in FCS-free medium for up to 8 days, and, for the first time, were also able to observe the conduction of these cell contractions. The ultrastructural characteristics of cultured smooth-muscle cells during contractile activity, were also examined by electron microscopy. The cells were mature and well-differentiated, and were packed with numerous myofilaments. They had developed long cell processes, and were linked to one another by gap junctions. These observations indicated that the smooth-muscle cells, cultured without FCS for 7 to 8 days, were morphologically mature and maintained their contractile activity, whereas the cells cultured in FCS-containing medium showed no detectable signs of contractile activity.
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  • 38
    ISSN: 1432-0878
    Keywords: Chemoreceptor ; Ultrastructure ; Parasitic copepod crustacean ; Pachypygus gibber
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The topography, external structure and ultrastructure of a cephalic sense organ, described for the first time, were studied by light and electron microscopy in the parasitic copepod Pachypygus gibber. This species is unusual in that it has three reproductive sexual forms (two males, one female).The cephalic organ, present only in the atypical male, is made up of numerous functional units, each composed of 4 cells: two sensory cells, one basal enveloping cell and one apical canal-forming cell opening outside via a pore. Many hundred pores are situated within the cuticle of the ventral pleural borders. Through each pore protrude two ciliary endings. An interesting feature is that the ciliary ends are without cuticular cover and thus, directly exposed to the surroundings, a situation unique in arthropods. The structural characteristics of this sense organ and the particular mode of life of the atypical male (with an additional free planktonic phase), lead to the hypothesis that its function is linked to chemical reception in the complex behavioural patterns such as host and sex recognition, during the free life.
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  • 39
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    Cell & tissue research 245 (1986), S. 457-460 
    ISSN: 1432-0878
    Keywords: Anterior pituitary ; Somatotroph ; Lactotroph ; Ultrastructure ; Immunocytochemistry ; Fetal and neonatal rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of immunoreactive somatotrophs and lactotrophs in pituitaries of fetal rats at 19, 20 and 21 days of gestation and on the day of birth was studied. Somatotrophs, first detectable at 19 days of gestation, undergo only minor modifications before reaching the structure described for adults. In particular there is an increase in the endoplasmic reticulum and Golgi apparatus. Lactotrophs, first identifiable in newborn rats, are very different in ultrastructure from adult cells, because the secretory granules are generally small, but variable in shape and size, and the Golgi complex is prominent.
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  • 40
    ISSN: 1432-0878
    Keywords: Organ culture ; Amelogenesis ; Dentinogenesis ; Ultrastructure ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Molar tooth germs from three-day-old rats were cultured successfully for fourteen days, permitting the study of the development in vitro of both extracellular matrix and cellular elements such as odontoblasts and ameloblasts. The ultrastructure of the cultured tooth germs was compared with the ultrastructure of tooth germs in vivo at a comparable developmental stage. Progenitor cells of odontoblasts and ameloblasts were found to differentiate in vitro. Odontoblasts seemed to contain more lysosome-like bodies and fewer secretory granules than in vivo. They formed normally mineralizing dentine or a thick layer of dense, unmineralized predentine with incidentally some amorphous, extracellular material. Enamel was exclusively present opposite well developed dentine. It was often hyperor hypomineralized and enamel rods were not as regularly shaped as in vivo. In places where no enamel formation had taken place, large amounts of amorphous extracellular material were sometimes seen. From these observations it can be concluded that cellular development in cultured tooth germs appeared more or less normal, but extracellular matrix formation and mineralization were sometimes disturbed.
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  • 41
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    Cell & tissue research 244 (1986), S. 165-171 
    ISSN: 1432-0878
    Keywords: Iridophores ; Motility ; Innervation ; Ultrastructure ; Teleost (Odontobutis obscura)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Reflecting chromatophores in the dermis of the skin of a freshwater goby, Odontobutis obscura, are of an iridophore type. These chromatophores contain numerous reflecting platelets, which are similar to those in iridophores of other fish and amphibian species. It was found that these iridophores are motile, i.e., these cells respond to certain stimuli with translocation of the platelets within the cells. K+ ions induced dispersion of the platelets in excised scale preparations, but not in excised scales from chemically denervated fish. Norepinephrine and melatonin also induced dispersion of the platelets. Alpha-MSH was effective in aggregating these organelles into the centrospheres of the cells. The conclusions reached are: (1) iridophores of O. obscura are motile; (2) the movement of the iridophores is under nervous and hormonal control.
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  • 42
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    Cell & tissue research 243 (1986), S. 405-414 
    ISSN: 1432-0878
    Keywords: Leydig cells ; Ethane dimethanesulphonate ; Ultrastructure ; Destruction ; Gonadotrophins ; Testosterone ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The cytotoxic effects of ethane dimethanesulphonate upon rat Leydig cells were examined ultrastructurally up to 3 days after treatment and related to changes in serum levels of gonadotrophins and testosterone. Six hours after administration of ethane dimethanesulphonate the usual tubulo-vesicular morphology of Leydig-cell smooth endoplasmic reticulum was converted to small vesicles and the Golgi apparatus showed focal hypertrophy into anastomosing tubules. These changes became more marked by 12 h with many Leydig cells exhibiting karyopyknosis and hyperchromatism. Necrotic Leydig cells were often engulfed by macrophages, the latter containing pyknotic fragments of Leydig cells within their cytoplasm. One day after administration, advanced necrosis of Leydig cells occurred, many of which were phagocytosed by macrophages, and on day 3, destruction of Leydig cells was complete resulting in their elimination from the interstitial tissue, which contained only loose connective tissue and macrophages. Structural alterations to the Leydig cells from 6–24 h was reflected by a significant reduction in serum testosterone levels which further declined to the limits of detection accompanying the abolition of Leydig cells on day 3. These changes were paralleled by a significant elevation of serum LH and FSH levels suggesting diminished feedback regulation of pituitary gonadotrophin secretion. The results indicate that ethane dimethanesulphonate is a rapidly acting Leydig cell toxin which may be a useful experimental tool in further studies of spermatogenic function mediated via Sertoli cell-Leydig cell interaction.
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  • 43
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    Cell & tissue research 244 (1986), S. 493-499 
    ISSN: 1432-0878
    Keywords: Endothelium ; Capillaries ; Kidney ; Ultrastructure ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A new endothelial cell structure, named the endothelial pocket, has been found by combined transmission and scanning electron microscopic studies of renal peritubular capillaries. Transmission EM observations made on these and other fenestrated capillaries demonstrated that each pocket consists of an attenuated fold of fenestrated endothelium that projects 200 nm into the lumen above the rest of the endothelial surface. Beneath this luminal fold, there is a space and then another layer of fenestrated endothelium which abuts the basal lamina. The linear density of endothelial pockets was measured in the capillaries of the kidney cortex, intestinal mucosa and exocrine pancreas in mice and determined to be 0.067, 0.017 and 0.007 pockets·μm-1 respectively. Cationic ferritin decoration of the anionic sites on the luminal surface of the endothelium in these capillary beds revealed that both unlabelled and labelled diaphragms are clustered. In such specimens, the majority of the luminal diaphragms on endothelial pockets did not have cationic ferritin binding sites detectable by either scanning or transmission EM. On this account as well as on account of their general morphology, endothelial pockets appear to be multifold versions of the simple transendothelial channel.
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  • 44
    ISSN: 1432-0878
    Keywords: Capillary ; Epithelium ; Retina ; Retinal pigment epithelium ; Ultrastructure ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Light- and urethane-induced retinopathies in rats are characterized by loss of photoreceptors. Retinal capillaries subsequently become incorporated into the normally avascular retinal pigment epithelium. These models provided an opportunity to study the response of epithelial cells to closely apposed capillaries, in order to determine if capillaries contribute to the polar organization of epithelial cells. Pigment epithelial cells reorganized their lateral plasma membrane where the latter faced intraepithelial capillaries. This normally flat, undifferentiated membrane developed attachment sites, folds and intracytoplasmic tubules, and exhibited endocytosis and putative basal lamina secretion. These structural and functional specializations are normally restricted to the basal plasma membrane — the normal vascular front of the cell facing the dense meshwork of capillaries constituting the choriocapillaris. We conclude that RPE cells, and perhaps epithelia in general, polarize in response to an adjacent capillary bed.
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  • 45
    ISSN: 1432-0878
    Keywords: VIP ; Nerve fibers ; Ganglion cells ; Chromaffin cells ; Ultrastructure ; Adrenal gland ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary VIP-like immunoreactivity was revealed in a few chromaffin cells, medullary ganglion cells and a plexus of varicose nerve fibers in the superficial cortex and single varicose fibers in the juxtamedullary cortex and the medulla of the rat adrenal gland. VIP-like immunoreactive chromaffin cells were polygonal in shape without any distinct cytoplasmic processes and they appeared solitarily. Their cytoplasm contained abundant granular vesicles having a round core and the immunoreactive material was localized to the granular core. VIP-immunoreactive ganglion cells were multipolar and had large intracytoplasmic vacuoles. The immunoreactive material was localized not only in a few granular vesicles but also diffusely throughout the axoplasm. VIP-immunoreactive varicose nerve fibers in the superficial cortex were characterized by abundant small clear vesicles and some large granular vesicles, while those in the juxtamedullary cortex and medulla and the ganglionic processes were characterized by abundant large clear vesicles, as well as the same vesicular elements as contained in the nerves in the superficial cortex. The immunoreactive material was localized on the granular cores and diffusely in the axoplasm in both nerves. Based on the similarity and difference in the composition of the vesicles contained in individual nerves, it is likely that the VIP-immunoreactive nerve fibers in the medulla and the juxtamedullary cortex are derived from the medullary VIP-ganglion cells, while those in the superficial cortex are of extrinsic origin. The immunoreactive nerve fibers in both the cortex and the medulla were often in direct contact with cortical cells and chromaffin cells, where no membrane specializations were formed. The immunoreactive nerve fibers were sometimes associated with the smooth muscle cells and pericytes of small blood vessels in the superficial cortex. In addition they were often seen in close apposition to the fenestrated endothelial cells in the cortex and the medulla, only a common basal lamina intervening. Several possible mechanisms by which VIP may exert its effect in the adrenal gland are discussed.
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  • 46
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    Cell & tissue research 243 (1986), S. 137-144 
    ISSN: 1432-0878
    Keywords: Lung ; Blood-air barrier ; Surfactant ; Ultrastructure ; Freeze fracture ; Birds ; Penguin (Aptenodytes forsten)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Of all avian species the emperor penguin is the best adapted bird to attain the greatest diving depths and diving durations. Therefore the lung of this bird was investigated with electron-microscopic, i.e., freeze-fracture and thin-section methods. The parabronchi are surrounded by bundles of smooth muscle cells innervated by varicosities of autonomic nerves. The parabronchial epithelium is flat, bears a few microvilli and does not show any conspicuous ultrastructural specializations; only individual cells contain secretory granules. The atrial epithelial cells bear apical microvilli and are interconnected by adhering and tight junctions (5–10 sealing strands), the latter presumably forming an effective barrier against paracellular fluid movements. The cells contain lamellar inclusions of two types: (i) round membrane-bounded granules, the lamellar content of which is fixation-labile, and (ii) large polymorphic compact deposits of well-preserved lamellae. In both types of inclusions the individual lamellae can be of trilaminar appearance, whereas their fracture faces are smooth. Lamellar material also covers the epithelium of atria, infundibula and air capillaries. In thin areas the diameter of the morphological blood-air barrier measures 220–330 nm. Usually the endothelium of the blood capillaries is thicker (40–180 nm) than the air capillary epithelium (25–150 nm). Both epithelium and endothelium are interconnected by tight junctions, which seem to be more extensive and presumably tighter in the epithelium than in the endothelium. Frequently the common basal lamina is the thickest individual component of the blood-air barrier, measuring between 170–230 nm. Often collagen fibrils occur in this area of the barrier. In comparison with that of other birds the entire blood-air barrier of the emperor penguin is relatively thick, probably owing to an adaptation of the lung tissue which must resist high hydrostatic pressure during diving excursions.
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  • 47
    ISSN: 1432-0878
    Keywords: Parathyroid gland ; Protein A-gold technique ; Ultrastructure ; Storage granules ; Mammals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron-microscopic immunocytochemistry for the demonstration of parathormone in parathyroid chief cells was performed in adult male rats, gerbils, mice, and dogs, using the protein A-gold technique. Protein A-gold particles were detected over both large and small secretory granules in all the animals examined. In the former, they were concentrated not only over type-I granules with a large core, but also over type-II granules with a small core. They were also located over atypical granules, including heterogeneously dense granules, granules having vesicles in a finely particulate core, and distorted granules. All labelled secretory granules were characterized by the presence of a clear halo of varying width around the core. Occasionally, Golgi cisternae as well as Golgi vacuoles with a finely particular content were also labelled. The labelling of the secretory granules was strong in dogs, moderate in rats and gerbils, and weak in mice. In addition, it was more intense in the non-osmicated preparations than in the osmicated preparations. The frequency of both types of large granules showed species differences. The possible factors involved in these differences are discussed.
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  • 48
    ISSN: 1432-0878
    Keywords: Peripolar cells ; Juxtaglomerular apparatus ; Kallikrein ; Ultrastructure ; Mammals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Peripolar cells are granulated glomerular epithelial cells that form a cuff around the vascular pole of the glomerulus. Quantitation of these cells in 17 species of mammals (including man, several laboratory animals and a variety of other species) indicated that they were detectable by light microscopy in all but one of the mammals that were examined (the Australian hopping mouse). In adult mammals with detectable peripolar cells, the “peripolar cell index” (the percentage of randomly sectioned glomeruli that displayed peripolar cells in histological sections of kidney) ranged from 0.15 (for echidna) to 11.86 (for sheep). Newborn lambs and rats showed strikingly high values (23.30 and 10.76, respectively) compared with their adult counterparts. Using electron microscopy, peripolar cells were observed in all species that were examined, including the Australian hopping mouse. Morphologically, peripolar cells were similar in all species although their size and granule population varied. They showed a predominantly outer cortical glomerular distribution and a close anatomical relationship with the renin-containing myoepithelioid cells. These findings indicate that peripolar cells are present in a wide variety of species and support the view that such cells may play a significant role in the regulation of normal renal function.
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  • 49
    ISSN: 1432-0878
    Keywords: Uterus ; Epithelium ; Ultrastructure ; Pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the endometrial epithelium of the pig was studied during the estrous cycle and early pregnancy up to implantation. Special attention was given to the luminal epithelium and morphological indications of protein synthesis. Although the general morphology of the luminal and glandular epithelia is similar (both tissues consist of secretory cells and ciliated cells at all the stages studied), it appears that the two epithelia should be considered as two functionally different units in the pre-implantation period. Morphological evidence suggests the presence of at least three different secretory products within luminal epithelial cells; they are released at different times, i.e. at estrus, between day 8 and 10 and after day 11. The glandular epithelium shows release of secretory products from day 10–11. Increasing amounts of glycogen were found within epithelial cells, especially in pregnant gilts from day 12. The possible significance of secretory activity of the epithelium is discussed in relation to the development of the embryos.
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  • 50
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    Plant systematics and evolution 153 (1986), S. 259-264 
    ISSN: 1615-6110
    Keywords: Gymnosperms ; Angiosperms ; Pteridosperms ; Caytoniales ; Caytonanthus ; Ultrastructure ; pollen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The pollen grain wall structure ofCaytonanthus arberi was studied with SEM and TEM. The monosulcate, bisaccate pollen grain of this taxon has an alveolar wall structure that is more like that found in saccate Conifers than primitive Angiosperms. Pollen grain morphology does not support a Caytonialean ancestry for the Angiosperms.
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  • 51
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    Plant systematics and evolution 154 (1986), S. 31-39 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Lactoridaceae ; Ultrastructure ; pollen ; fossil pollen (Cretaceous)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The pollen wall ultrastructure of the primitive AngiospermLactoris fernandeziana Phil. (Lactoridaceae) is described. The monosulcate aperture, granular wall structure and sacci (all primitive features) suggest placement of this family in theMagnoliales. Pollen ofLactoris is compared to fossil dispersed pollen from the Lower and lower-Upper Cretaceous. The fossil pollen shares characteristics which are restricted to theLactoridaceae suggesting that this family was present during the early Cretaceous.
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  • 52
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    Protoplasma 131 (1986), S. 1-10 
    ISSN: 1615-6102
    Keywords: Cell division ; Lomentaria ; mitosis ; Red algae ; Rhodophyta ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Mitosis in the marine red algaLomentaria baileyana (Rhodymeniales, Rhodophyta) was studied with the electron microscope. Nucleus associated organelles known as polar rings (PRs) migrate to establish the division poles at prophase. At prometaphase, shallow invaginations in the nuclear envelope (NE) form on two sides of each PR and soon rupture. The gaps that are consequently formed contain several small fragments of NE. A larger region of NE remains intact between the two gaps. By metaphase several cisternae of perinuclear endoplasmic reticulum (PER) have enclosed most of the nucleus but remain absent from the polar regions. The nucleolus disperses partially and a typical metaphase plate of chromosomes is formed. Each PR has disjoined into separate proximal and distal portions. MTs converge widely on all regions of the polar area, but do not extend into the cytoplasm. Some MTs end near or at the chromosomes while others extend slightly farther past the chromosomes or diagonally to the NE. As chromosomes move to opposite poles at anaphase, they are accompanied by nucleolar material. An interzonal midpiece (IZM) is created as the pole to pole distance increases and the NE remains intact except for the polar gaps. Following detachment from the IZM, the daughter nuclei are separated by a large central vacuole as a cleavage furrow develops and eventually constricts to form two cells following pit connection formation. It is suggested that mitosis inLomentaria represents an evolutionary intermediate between that seen in the higher and lower groups of red algae. This conclusion is in agreement with conventional morphological and light microscopic criteria used to placeLomentaria in theRhodymeniales, which is considered to be the next to most advanced order in theRhodophyta.
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  • 53
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    Protoplasma 134 (1986), S. 154-162 
    ISSN: 1615-6102
    Keywords: Cell division ; Leishmania ; Mitosis ; Ultrastructure ; Kinetoplastida
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The interphase nucleus ofLeishmania adleri has clumps of chromatin associated with the nuclear envelope and a large centrally located nucleolus. Prior to mitosis the basal bodies replicate at the cell anterior. Subsequently, dense plaques appear in the equatorial region of the nucleus at the time of spindle development. Microtubules appear in the nucleus adjacent to the nuclear envelope and embedded in the matrix of the plaques. A central spindle composed of a single bundle of microtubules develops and spans the nucleus. Plaques and nucleolar components laterally associate with the spindle and migrate towards the poles. The central spindle elongates to three to four times its original length separating the forming daughter nuclei and producing an interzonal spindle. A remnant of the interzonal spindle remains attached to each of the daughter nuclei until late into cytokinesis. The kinetoplast does not divide until after the completion of mitosis.
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  • 54
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    Protoplasma 131 (1986), S. 166-173 
    ISSN: 1615-6102
    Keywords: Chloroplast development ; Pisum sativum ; Prolamellar body ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We analyzed transformation, recrystallization, splitting and dispersion of prolamellar bodies during chloroplast development in pea seedlings illuminated by white, red and blue light of low intensity. With the help of a stereometric method we determined that there was a significant increase of prolamellar body number and a sharp decrease of their volume in differentiating chloroplast even in the first 2 hours of illumination. Decrease of prolamellar body dimensions was due both to gradual dispersion of its elements into primary thylakoids (indicated by the decrease of total volume of prolamellar bodies in plastid) and to splitting of prolamellar bodies (indicated by the increase of number of promellar bodies in plastid). Red light was more effective in transformation, splitting and dispersion of prolamellar bodies than blue light during the first 8–12 hours. Longer treatment with blue light had a stronger influence on these processes and on complete recrystallization than other light treatments.
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  • 55
    ISSN: 1615-6102
    Keywords: Chlamydomonas ; Endoplasmic reticulum ; Golgi apparatus ; Wall mutants ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Ultrastructural observations on the principal endomembranes (endoplasmic reticulum, Golgi apparatus) of synchronously growing of wild type and mutant (CW 2, CW 15) strains ofChlamydomonas reinhardii have been carried out. The dictyosomes of the Golgi apparatus in all three cases are highly polar in morphology but lack intercisternal filaments. A clear spatial relationship between dictyosomes and endoplasmic reticulum is seen and a transfer of vesicles from the latter to the former is easily visualized. Coated vesicles invariably appear to be restricted to the trans-pole of the dictyosomes. The endoplasmic reticulum adjacent to the cis pole of dictyosomes is considerably hypertrophied in the case of the wild type, only partially so in the mutant CW 2 but not at all in the mutant CW 15. In the wild type this swelling is most extreme during the period of wall deposition and for several hours afterwards. The results are discussed in relation to the biosynthesis and intracellular transport of, particularly O-glycosidically linked, glycoproteins.
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  • 56
    ISSN: 1615-6102
    Keywords: Chloroplast development ; Grana formation ; Pisum sativum ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We analyzed the formation of thylakoids and grana during the development of pea chloroplasts, illuminated by white, red and blue low intensity light. The total length of granal and intergranal thylakoids, and the length of granal thylakoids per unit area of plastid section were measured. Initially the greatest increase in length of granal thylakoids and the highest incidence of grana with large thylakoid content occurred in red light. On the other hand, with illumination times of over 12 hours blue light appeared to be more efficient in stimulating grana formation and thylakoid growth.
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  • 57
    ISSN: 1615-6102
    Keywords: Diapensia lapponica ; Mitochondria ; Morphometry ; Seasonal variation ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Seasonal changes in the mitochondrial ultrastructure were examined in palisade parenchyma cells of a tuft-formingDiapensia lapponica L. collected at monthly intervals in Northern Finland. Quantitative analyses to measure volume and surface densities were conducted during different periods of growth (stages of growth, acclimation, winter period and deacclimation) in the annual cycle. The volume density was highest in the summer and lowest in the spring; the difference was significant with both fixatives used GA and GA/FA. The largest membrane area (the mitochondrial outer membrane and the cristal membranes together) was observed in the summer and autumn, and was significantly less in the winter and spring. This correlated with fewer mitochondria in the spring and a smaller number of cristae in the winter and spring. In the material fixed in GA/FA the distribution of length/width ratios of mitochondria was relatively uniform in all seasons. However, the mitochondrial ultrastructure had the most varied appearance during the winter. Hypertonie GA/FA solution did not cause significant differences either in the ultrastructure or the volume and surface densities of the mitochondria.
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  • 58
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    Protoplasma 135 (1986), S. 102-111 
    ISSN: 1615-6102
    Keywords: Ultrastructure ; Haptoglossa mirabilis ; Differentiation ; Gun cell
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The most prominent ultrastructural characteristics of the cyst ofHaptoglossa mirabilis are a large centrally-placed nucleus which is partially ringed by three or four parallel cisternae of rough endoplasmic reticulum (r-ER), a centriole pair and single large Golgi complex which occupy the anterior end of the cell, and a population of provacuoles which occupies the posterior. During germination these organelles migrate into a narrow germ tube which subsequently expands to form the gun cell initial. The extracellular components of the attack apparatus (i.e. missile and injection tube) are formed entirely in the developing gun cell; indirect evidence suggests that both the Golgi complex and r-ER are involved in their synthesis. The intra-cellular component of the attack apparatus comprises the posterior, anterior and apical vacuoles. The posterior vacuole forms by fusion and expansion of the original cyst provacuoles; the formation of the anterior and apical vacuoles occurs late in gun cell differentiation and involves fusion of Golgi-derived vesicles.
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  • 59
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    Protoplasma 134 (1986), S. 102-110 
    ISSN: 1615-6102
    Keywords: Isoelectric focusing ; Isolation ; Potato tuber cell walls ; Purification ; Salt extraction ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A preparative procedure for cell wall isolation and purification was developed. The purity of the isolated cell walls was judged biochemically by the lack of activity of cytoplasmic marker enzymes and morphologically by examination at both the light and electron microscope levels. The purified cell walls were extracted with various salt treatments and the molecular weight range of most of the extracted proteins was between 14 and 31 kDa. The salt extracted hydrolytic enzymes were basic in nature (pI〉7.0) compared to their cytosolic counterparts (pI〈7.0). Some enzymes were readily extracted from cell walls (β-glucosidase and β-NAcglucosaminidase) with high salt treatment while most of the α-mannosidase activity associated with purified cell walls could not be removed even with sequential high salt treatments.
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    Protoplasma 135 (1986), S. 119-129 
    ISSN: 1615-6102
    Keywords: Differentiation ; Pectin ; Phytophthora ; Surface ; Ultrastructure ; Zoospore
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Populations ofPhytophthora palmivora zoospores induced to undergo synchronous differentiation by the addition of pectin showed an ordered sequence of surface changes. Within 10 seconds “blebs” and “microvilli” appeared on the cell and flagellar surfaces. These projections gave the zoospore a highly irregular and even convoluted surface for up to 30 seconds poststimulation. Between 30 and 40 seconds, pits appeared on the surface, which began to assume a smoother texture. Zoospores then rounded up and by 4 minutes had assumed an almost spherical form. At this time the surface became wrinkled as though shrinkage had occurred. Germ tubes could be seen emerging from almost all cells by 40 minutes, and as germ tubes enlarged, the cell surface became smooth again but with a fibrous texture. Many zoospores retained their flagella through to the germling stage. When cells were stimulated in iso-osmotic rather than hypo-osmotic media, germ tubes in most cases emerged at or very near the site of flagellar attachment. Differentiation in iso-osmotic media showed the same sequence except that the cells did not assume the spherical shape normally characteristic of cysts and germlings differentiating under hypo-osmotic conditions. Strontium-induced differentiation again followed the same general sequence as desribed above, although the cell surface was noticeably more convoluted and irregular prior to the stage of the formation of pits, and flagella were always shed between 40 seconds and 1 minute. Calcium addition up to 20 seconds after the initiation of differentiation with pectin prevented a high proportion of zoospores from encysting, the cells remained motile, and although the frequency of surface blebs and microvilli increased, pits did not appear. These surface changes are consistent with those expected during stimulus-mediated secretion, and it appears that calcium is able to inhibit differentiation only before the secretory step (pit formation).
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  • 61
    ISSN: 1615-6102
    Keywords: Dark-stress ; Recovery ; Root-nodules ; Soybean ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Root-nodules of soybean plants dark-stressed for 8 days and then allowed to recover for up to 17 days were examined by transmission electron microscopy. Control nodules possessed all the ultrastructural features characteristic of infected and uninfected nodule cells. Minimal changes in the appearance of host cells and bacteroids occurred during the first four days of dark stress. After 8 days of dark stress, damage was observed in the cellular and organelle membranes; however, very few changes were observed in the bacteroids. Nodule structure continued to degrade during the first two days of recovery after which time nodules either recovered or completely degraded. In the former case, structural integrity returned to all nodule cells. In the latter case all structural integrity of the host cell disappeared; however, bacteroids appeared intact suggesting that they remained viable.
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  • 62
    ISSN: 1615-6102
    Keywords: Root meristems ; Cell plate ; Ultrastructure ; 2,6-dichlorobenzonitrile
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The effect of 2,6-dichlorobenzonitrile on cytokinesis of meristematic cells of onion root during both treatment and recovery has been studied by electron microscopic techniques. 2,6-dichlorobenzonitrile interferes with cell plate formation in such a way that Golgi apparatus vesicles of treated cells appear to be different than controls and seem to coalesce as anomalous partial cell plates. During recovery, an apparently normal progression of cytokinesis is observed and abnormal portions of the cell plate are retained. Nuclear constrictions are observed frequently during recovery as a result of temporal alterations in cytokinesis. Our results show that 2,6-dichlorobenzo-nitrile induces anomalous and/or incomplete cell plates, which might be caused by an altered function of Golgi apparatus.
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    European journal of plastic surgery 9 (1986), S. 122-129 
    ISSN: 1435-0130
    Keywords: Congenital lymphoedema in dogs ; Ultrastructure ; Chronic lymphoedema ; Chronic inflammation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In two congenitally lymphoedematous dogs, a quantitative fine structural study was made of the subcutaneous tissue. It was found that the blood vessels, inital lymphatics and tissue channels all increased considerably, as did the small vesicles and vacuoles in the endothelium of both blood and lymph vessels. Collagen, fibroblasts, macrophages, and fat containing macrophages “fat cells” all increased greatly, while the small and medium lymphocytes increased to a moderate extent. These results are similar to those found in chronic experimental lymphoedema in dogs, in chronic high-protein oedema and in chronic inflammation. The underlying similarity of all these conditions is emphasised.
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    European archives of oto-rhino-laryngology and head & neck 243 (1986), S. 265-268 
    ISSN: 1434-4726
    Keywords: Respiratory cilia ; Measurement of ciliary orientation ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We have created a method for measuring the orientation of cilia in the respiratory epithelium. Ciliary orientation is the direction perpendicular to the plane defined by the central tubules of the cilia and is an estimate of ciliary beat direction. Ciliary orientation can be estimated by measuring the angle between the plane defined by the central tubules and a reference line. The standard deviation of these measurements describes the variation present in the beat directions of the cilia. The reference line must be so chosen that the majority of measurements falls at about the middle of the 0°–180° range. We tested measurements by using both a glass angle measure and a semiautomatic image analyzer (IBAS I). The latter approach was faster and more reproducible. We made our measurements of normal tissues on samples obtained from two healthy adult non-smokers. Measurements were made in four areas of each sample, with 59–110 cilia in each. The differences between the maximum and minimum angles of the ciliary orientation in the same area varied from 167.9° to 85.4° from the reference line. The standard deviation varied from 18.0° to 35.4° and we consider this to be a normal variation in ciliary orientation. Of the cilia, 57% were within a standard deviation of 20°.
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    Journal of Orthopaedic Research 4 (1986), S. 27-36 
    ISSN: 0736-0266
    Keywords: Ultrastructure ; Polymorphic cells ; Medullary canal ; Direct current ; Capillary ; Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The ultrastructural changes in the medullary canal of the adult male New Zealand white rabbit associated with the trauma of the insertion of an inactive cathode were compared to that associated with electrically induced osteogenesis from an active cathode delivering 20 μA constant direct current. In the vicinity of both an inactive and an active cathode, the medullary canal cellular content was replaced first by polymorphic cells and later by osteoblastic new bone formation. The polymorphic cells always appeared in the immediate vicinity of a capillary or other blood vessel. With time, the new bone formation in the medullary canal surrounding the inactive cathode disappeared, while new formation surrounding the active cathode progressively increased in amount. When the new bone formation in the medullary canal surrounding an inactive cathode disappeared, it was replaced by a network of polymorphic cells. When direct current was then applied to such an inactive electrode, the polymorphic cells were again rapidly replaced by bone. The close association of polymorphic cells with osteoblasts suggests that the former may be a precursor cell of the latter.
    Additional Material: 14 Ill.
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    Journal of Electron Microscopy Technique 4 (1986), S. 147-156 
    ISSN: 0741-0581
    Keywords: Identified neuromuscular junctions ; Freeze fracture ; Active zones ; Synaptic efficacy ; Ultrastructure ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Natural Sciences in General
    Notes: We developed a technique for freeze-fracturing single physiologically identified neuromuscular junctions. This technique permits direct comparison of quantal content with morphological variables such as active zone length per unit terminal length for the same cell. The technique was developed to elucidate the structural basis for variability in transmitter release at the neuromuscular junction. The procedures were as follows: (1) record quantal content by conventional intracellular recordings; (2) mark cells for identification by fluorescent dye injection; (3) fix and stain endplate cholinesterase; (4) glycerinate and remove single fibers from the muscle; (5) draw endplate morphology; (6) freeze-fracture single muscle fibers; (7) examine in a transmission electron microscope; and (8) photograph and measure nerve terminal membrane ultrastructure. We found that approximately 15% of freeze-fractured single muscle fibers exhibited nerve terminal active zones. To demonstrate the usefulness of this technique, physiological and morphological information from an identified junction is presented. Freeze-fracture of identified cells has several advantages over thin sections, which cannot accurately show such things as active zone length, spacing, or intramembrane particles. This technique also has applications to the study of active zone ultrastructure in situations where neurotransmitter release is known to differ from normal levels. In addition, direct correlations between membrane structure and function can be studied in other preparations by this method.
    Additional Material: 5 Ill.
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  • 67
    ISSN: 1432-2307
    Keywords: Lathyrism ; Capillaries ; Rat ; Ultrastructure ; Flavonoids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of rat myocardial capillaries was studied in the course of experimental lathyrism. Endothelial cells were hypertrophic, with a sinuous profile of the plasma membrane facing the lumen and with a consistent increase of pinocytotic vesicles; the nuclei were irregular in shape; ATPase activity was no more demonstrable. Therefore, various and well distinct structural endothelial mechanisms seem to be primarily involved, causing an alteration of the dynamics of transcellular exchanges and of the permeability of the vascular wall. Simultaneous treatment with certain flavonoids, (O-(β-hydroxyethyl)-rutosides and Na(+)-epicatechin-2-sulfonate), resulted in a less pronounced alteration and a more rapid recovery. The possibility of the existence of a common site of action of lathyrogens and flavonoids is raised in the discussion.
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    Anatomy and embryology 146 (1975), S. 301-311 
    ISSN: 1432-0568
    Keywords: Endocrinology ; Ultrastructure ; Adrenal cortex ; Avian Physiology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructural characteristics of the interrenal cell were investigated in the quail and the pigeon after fixation by intravascular addominal perfusion. These is no significant fine structural difference between cells belonging to subcapsular and central regions of the gland. The interrenal cell in both species possesses nuclear bodies, polymorphic mitochondria with tubulo-vesicular cristae and tubular crystalline inclusions, considerable amounts of endoplasmic reticulum, ergastoplasm, a well developed Golgi apparatus, coated vesicles, microtubules, filaments, cilia, ribosomes, a profusion of liposomes, dense bodies with varied inner structure, pinocytic invaginations of cell membrane and intercellular attachment devices. The pigoen adrenocortical cell also possesses intranuclear lipidlike inclusions and fibrous bundle (this being never recorded in adrenocortical cell), annulate lamellae, and a variety of cytosomes, probably lipofucsin in nature. The significance and cytophysiological role of various organelles and inclusions have been discussed in the light of earlier data obtained on avian adrenocortical cells.
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    Anatomy and embryology 148 (1975), S. 47-58 
    ISSN: 1432-0568
    Keywords: Rat ; Endometrium ; Ultrastructure ; Progesterone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effects of various dosages and of various time periods of treatment with progesterone have been studied in the spayed, mature rat. Test objects were the cells of the luminal epithelium and of the endometrial stroma which were examined by qualitative and quantitative electron microscopy. No significant response was observed in epithelial or stromal cells until after 12 hrs of progesterone treatment. The nuclei of both cell types were then more circular than earlier with reduced long diameters. The functional significance of this change in configuration is unclear since only in the stromal cells was it followed by nuclear growth. Further, after 12 hrs of treatment the relative amounts of mitochondria and granular endoplasmic reticulum of stromal cells were reduced while the volume of the stromal cell cytoplasm appeared enlarged. This is taken as evidence that progesterone causes an intracellular oedema probably by decreasing cell membrane permeability. This response is probably not specific for the stroma but also includes the luminal epithelium, although the volume of the epithelial cell cytoplasm could not be determined here. Nucleolar enlargement did occur in stromal cells and was observed after 12 hrs of treatment but was not significant until after 24 hrs. At this point of time the net amount of granular endoplasmic reticulum in stromal and epithelial cells was increased indicating an increased protein synthesis in both cell types. However, only in the stromal cells was this associated with nucleolar enlargement, which supports the idea that progesterone stimulates protein synthesis through different mechanisms in the two cell types. Testing various dosages of progesterone showed that 0.5 mg had an effect similar to 5 mg of progesterone. When 0.05 mg progesterone was injected the only effect observed was an increase in the amount of apical vesicles of the luminal epithelium, showing that the epithelium is more sensitive to progesterone than the stroma.
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    Anatomy and embryology 146 (1975), S. 265-277 
    ISSN: 1432-0568
    Keywords: Granulocytopoiesis ; Perihepatic layer ; Mesothelium ; Amphibia ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Der Peritoneal-Überzug und die subkapsuläre Region der Leber von Xenopus laevis wurden mit dem Elektronenmikroskop untersucht. Dabei wurde festgestellt, daß in der subkapsulären Region eine zwei bis zehn Zellschichten starke perihepatische Schicht vorhanden ist. Die perihepatische Schicht setzt sich zum größten Teil aus granulocytopoetischem Gewebe zusammen. Es wurden jedoch auch Lymphocyten, Pigmentzellen und Fettspeicherzellen gefunden. Das Vorhandensein einer perihepatischen granulocytopoetischen Schicht bei Xenopus laevis steht im Gegensatz zu der bisherigen Auffassung, daß die perihepatische Schicht ein typisches Merkmal der Urodelen sei. Es werden die phylogenetische Bedeutung einer solchen Schicht bei Anuren sowie die Entwicklungsvorgänge der einzelnen Zelltypen der perihepatischen Schicht diskutiert. Außerdem wird auf die mögliche Bedeutung der perihepatischen Schicht für immun-Vorgänge verwiesen.
    Notes: Summary The peritoneal cover and the subcapsular region of the liver of Xenopus laevis were examined with electron microscopy. In the subcapsular region a prominent perihepatic layer two to ten cells wide was found. This perihepatic layer is mainly composed of granulocytopoietic tissue. Other cell types found in the perihepatic layer were lymphocytes, pigment cells and fat storing cells. The presence of a perihepatic granulocytopoietic layer in the liver of Xenopus laevis is in contrast to current opinion that such a layer is a characteristic typical of urodeles. The phylogenetic significance of such a layer in anurans and the developmental processes of the individual cell types of the perihepatic layer are discussed. Furthermore the possible participation of the perihepatic layer in the immune response is considered
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    Anatomy and embryology 146 (1975), S. 245-264 
    ISSN: 1432-0568
    Keywords: Hepatocytes ; Amphibia ; Glycogen ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Leber von Xenopus laevis wurde mit dem Elektronenmikroskop untersucht. Dabei wurde festgestellt, daß sie in ihrem Bau stark von der Leber der Säuger abweicht, vor allem in Bezug auf die Morphologie des als typisch zu bezeichnenden Hepatocyten. Die Untersuchungen zeigten, daß eine solche Zelle primär Glykogenspeicherungs-Funktion besitzt und nur geringe Bestandteile an Organellen und anderen Inklusionen aufweist. Da dieser Zelltyp in der Leber unbehandelter Tiere am häufigsten auftritt, wurde er als Normalzelle bezeichnet. Bemerkenswert erschien die Tatsache, daß eine Vielzahl von Zelltypen in der Normalleber vorkommen, die sonst vermehrt unter experimentellen Bedingungen zu finden sind, z.B. Zellen mit stark vermehrtem RER, vergrößertem Golgi-Feld, vermehrten Lipidinklusionen etc. Diese hohe Zahl von abweichenden Hepatocyten und die Tatsache, daß alle Zwischenstufen zwischen den einzelnen Extremen vorhanden sind, die nicht durch die lage der Zelle innerhalb der Leber erklärt werden konnten, wurden als der Ausdruck eines zyklischen Durchlaufens der einzelnen Aktivitätsstadien interpretiert. Spezielles Interesse verdient die Tatsache, daß Glykogen in der Leberzelle vermehrt nur während der Vitellogenese abgebaut wird. Akuter und chronischer Hunger, sowie Kälte-adaptation beeinflussen die Morphologie der Normalzelle, besonders in Bezug auf das Glykogen kaum. Die möglichen Ursachen hierfür werden diskutiert.
    Notes: Summary The liver of Xenopus laevis was examined with electron microscopy. Its structure was found to be markedly different from that of mammals, particularly regarding the morphology of the hepatocytes to be classified as typical. It was established that the main function of such a cell is the storage of glycogen, and further that it possesses only scant organelles and other inclusions. Since this type of cell was found most frequently in the liver of untreated animals, it was designated as normal cell. The fact appears noteworthy that in the normal liver of Xenopus laevis an abundance of cell types occur which are otherwise found to be proliferated under experimental conditions, e.g. cells with pronouncedly augmented RER, enlarged Golgi complexes, increased lipid inclusions etc. This high number of divergent hepatocytes and the fact that all intermediate stages between the individual extremes are present and not to be accounted for by the position of the cell within the liver was interpreted as being the expression of a cyclic passage of the various stages of activity. It is of special interest that augmented degradation of glycogen in the liver cell takes place only during vitellogenesis. Acute and chronic hunger, as well as adaptation to cold, hardly affect the morphology of the normal cell, especially as far as the glycogen is concerned. The possible causes for this are discussed.
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    Anatomy and embryology 147 (1975), S. 243-258 
    ISSN: 1432-0568
    Keywords: Fixation ; Foetus ; Liver cells ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Light and electron microscopic investigations of the ability of various fixatives to preserve foetal pig liver tissue (immersion fixed 5 min, 20 min, and 40 min after the death of the mother) gave the following results: 1) Fixation with 4% formaldehyde gives, in all circumstances, an unacceptable tissue preservation. 2) Fixation with 2.5% glutaraldehyde gives fair tissue preservation in a ca. 130 μ thick zone below the surface. 3) Fixation with a fixative mixture containing 2% formaldehyde and 1.25% glutaraldehyde or 2% formaldehyde, 1% glutaraldehyde and 1% acrolein gives good tissue preservation in a ca. 500 μ thick zone under the surface. 4) The addition of DMSO does not improve tissue preservation. 5) Delayed fixation of liver tissue removed from the foetus after the uterus has been placed in an incubator for 40 min has only a slight effect on tissue preservation.
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  • 73
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    Acta neuropathologica 31 (1975), S. 353-361 
    ISSN: 1432-0533
    Keywords: Intranuclear Inclusions ; Creutzfeldt-Jakob Disease ; Ultrastructure ; Virus-Like Inclusions ; Nuclear Body
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Two types of intranuclear inclusions were described in a brain biopsy from a patient with Creutzfeldt-Jakob disease. The first type of intranuclear inclusion was papova virus-like and was observed within 20% of the nuclei of all astrocytes and neurons examined. The particles measured 32 nm in diameter and consisted of a dense core surrounded by a multilayered shell. The second type of intranuclear inclusion was a granulo-fibrillar nuclear body found within the nuclei of astrocytes and neurons. The possible significance of these inclusions to the etiology of Creutzfeldt-Jakob disease is discussed.
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  • 74
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    Acta neuropathologica 32 (1975), S. 333-339 
    ISSN: 1432-0533
    Keywords: Adult Metachromatic Leukodystrophy ; Polarization Microscopy ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The findings are described in an adult case of metachromatic leukodystrophy examined by light, polarization and electron microscopy. Symmetrical demyelination was found in the cerebral hemispheres, but was moderate in the cerebellum, brain stem and spinal cord. Early changes in myelin of peripheral nerves have been demonstrated by polarization microscopy. Various metachromatic structures have been described in glial cells and neurons by electron microscopy, indicating disturbances at different metabolic steps of lipid metabolism. There are minor but no essential ultrastructural differences in the disease of different ages.
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  • 75
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    Acta neuropathologica 32 (1975), S. 225-233 
    ISSN: 1432-0533
    Keywords: Tissue Culture ; Ultrastructure ; Chordoma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract This report concerns an electron microscopic study of a sacrococcygeal chordoma and its in vitro cultured cells. In vitro, the cells that proliferated in the early phase were predominantly non-vacuolated stellate cells, which were later transformed into vacuolated cells. This suggests that various cell types seen in vivo represent variants of the same cell type at different stages of differentiation and cellular activity. The in vitro tumor cells also show the origin of their vacuoles from both rough endoplasmic reticulum and Golgi membranes. The finding of amorphous and granular material and collagen fibrils in the extracellular spaces of cultured cells seems to suggest that chordoma cells have certain synthetic and secretory activity.
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  • 76
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    Acta neuropathologica 31 (1975), S. 117-127 
    ISSN: 1432-0533
    Keywords: Dark Neurons ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The lateral vestibular nucleus was studied by light and electron microscopy in normal rats as well as in rats in which the anterior cerebellar vermis was destroyed. Dark neurons were seen in many of the operated rats but were rarely found in normal control animals. The dark neurons were not seen in adjacent nuclei. In additional rats, it was found that anoxia, extra anaesthetic, postmortem rough handling, and sham operations did not increase the frequency of dark neurons. These data indicate that dark neurons might not always be artifactual and that the lateral vestibular nucleus appears to be a focal point for their occurrence.
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  • 77
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    Acta neuropathologica 31 (1975), S. 137-150 
    ISSN: 1432-0533
    Keywords: Thiamine Deficiency ; Wernicke's Encephalopathy ; Rhesus Monkey ; Ultrastructure ; Myelin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Experimental Wernicke's encephalopathy, induced in rhesus monkeys with a diet lacking thiamine (vitamin B1), is characterized by cavitary necrosis of the striatum as well as a microvacuolar periventricular lesion of the brain stem such as occurs in man. With high resolution light microscopy and electron microscopy, the primary structural alteration in the brain stem lesion, and probably also in the striatum, appears to be that of widespread “blister” formation due to splitting of myelin at the intraperiod line. Microvascular alterations were minimal, even in the most severely affected regions. It is the myelin blisters which give rise to the spongy texture of the neuropil. A similar splitting of myelin has been deseribed in several other experimental encephalopathies, and it is probable that it also occurs in Wernicke's encephalopathy in man.
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  • 78
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    Acta neuropathologica 31 (1975), S. 281-296 
    ISSN: 1432-0533
    Keywords: Werdnig-Hoffmann Disease ; Ultrastructure ; Denervation ; Muscle ; Myofibrils ; Centrioles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The authors describe in biopsies from 6 cases of Werdnig-Hoffmann disease, including 2 of the more benign type, the ultrastructural typical aspects of denervation. They compare their findings with those of other workers. The striking points are the great variation in the diameter of the muscle fibres and the myofibrils, the disorganisation of the myofibrils, the sarcomeres and the filaments, with persistance of the relations between thick and thin filaments at various levels, the modifications of the Z-band and the triads in chains. The folds and the basement membrane are examined. Centrioles are present in a muscle fibre and in a satellite. Glycogen is very abundant. The nerves seem normal but some Schwann cells contain π granules which are not observed usually at the age of the patient. The end plates and a muscle spindle are normal.
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  • 79
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    Acta neuropathologica 33 (1975), S. 9-21 
    ISSN: 1432-0533
    Keywords: Fabry's Disease ; Glycolipid ; Anhydrosis ; Pain ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A sural nerve biopsy of a patient with Fabry's disease showed depletion of larger myelinated fibres, but smaller myelinated and unmyelinated fibres were intact. Epineurial and to a lesser degree endoneurial vessels revealed abundant lamellar inclusions in the endothelial and perithelial cells. Larger myelinated nerve fibres contained glycogen granules in the vacuoles caused by splitting of the adaxonal membranes. A skin biopsy revealed abundant inclusions in the secretory cells and myoepithelial cells of the sweat glands. The lumen of the gland was packed with inclusions like those in the vessel walls. The pain and anhydrosis might be caused by accumulation of glycolipid in the vasa nervorum and sweat glands and not by autonomic nerve involvement.
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  • 80
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    Acta neuropathologica 33 (1975), S. 173-177 
    ISSN: 1432-0533
    Keywords: Mesothelioma ; Pleura ; Metastases ; Brain ; Ultrastructure ; Asbestos
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A malignant fibrous mesothelioma in a 52 year old white man arising from the left parietal pleura associated with lupus erythematosus with metastases to brain and liver is reported. Asbestos bodies were found in digested pulmonary tissue but none in the primary or metastatic lesions. Light microscopic and ultrastructural studies suggest that this tumor contains mesothelial or endothelial cells, some of which revealed fibroblastic features while others disclosed epitheloid characteristics.
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    Acta neuropathologica 33 (1975), S. 279-284 
    ISSN: 1432-0533
    Keywords: Hemangiopericytoma ; Leiomyoblastic differentiation ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Two intracranial hemangiopericytomas revealed subcellular features of the neoplastic elements comparable to those observed in normal and neoplastic smooth muscle. These included intracytoplasmic and submembranous fusiform dense bodies associated with bundles of filaments, tapered configuration of cells with grouping of cytoplasmic organelles at nuclear poles and deposition of intercellular basal lamina-like material. These observations are consistent with the pericytic origin but opposed to the ofttimes postulated meningothelial derivation of the neoplasm.
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  • 82
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    Diabetologia 11 (1975), S. 285-289 
    ISSN: 1432-0428
    Keywords: Ultrastructure ; pregnancy ; B-cell ; granule type ; light (pale) granules ; dark granules
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultramicroscopic appearence of the B-cell of the pregnant rat suggests hyperinsulinism of the individual beta cell. In pregnant rats the B-cell contains an increased volume and an increased number of light granules as well as enlarged mitochondria.
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    Experimental brain research 22 (1975), S. 13-24 
    ISSN: 1432-1106
    Keywords: Inferior olive ; Spinal afferents ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Identification of the direct spinal areas (portions of the dorsal and medial accessory nuclei) within the opossum inferior olivary complex was accomplished by mapping the location of the terminal degeneration by the Fink-Heimer technique subsequent to cervical cord lesions. Following similar lesions, sampling of these same regions for electron microscopic study was assured by examination of transversely oriented, 1 μ plastic sections prior to thin sectioning. The first evidence of electron dense axon terminals was found at a survival time of 24 hours. At survival times of 36, 48 and 72 hours, degenerating presynaptic profiles shrink, become irregular in shape and are totally or partially surrounded by glial processes. Spinal terminals average 1–2 μ in their greatest dimension, contain round, clear synaptic vesicles and generally contact small diameter (0.4–1.8 μ) dendritic shafts or occasional spiny appendages. The spiny dendritic appendages make up the central core of the olivary glomeruli and these juxtaposed dendritic processes exhibit gap junctions. At longer survival times (5, 7 and 9 days) many presynaptic profiles with either round or pleomorphic synaptic vesicles remain normal in appearance and contact dendritic shafts or the spiny appendages within glomeruli. Afferents from other sources (possibly including intrinsic neurons) must terminate within the direct spinal portion of the nuclear complex to account for the numerous axon terminals which retain normal morphology after such long survival times.
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  • 84
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    Pflügers Archiv 360 (1975), S. 121-134 
    ISSN: 1432-2013
    Keywords: Muscle cross ; Myosin ATPase ; Ultrastructure ; Fibre types ; Light chains of myosin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The slow anterior latissimus dorsi (ALD) muscles of newly hatched chiekens were transposed and cross-innervated by the mixed, predominantly fast superior brachialis nerve, and investigated 2 to 15 months after the operation. Two months after the operation, myosin ATPase activity of the cross-innervated ALD muscles was still as low as in the control ALD, although the ultrastructure and the histochemical ATPase activity already showed a mixed fibre-type pattern with a predominance of fast-type fibres around the site of nerve implantation. The change of myosin properties of the whole cross-innervated ALD did not occur until the third month after the operation. At that time, the myosin ATPase activity increased about 2.5 times and light chains of myosin of the fast type appeared in the electrophoretic pattern. The myosin ATPase activity attained 62% of the activity found in the control fast posterior latissimus dorsi muscles at three months; subsequently it remained at about this level reaching 68% 18 months after the operation. The results indicate that approximately two thirds of the corss-innervated ALD muscle fibres became changed towards the fast type under neural influence, whereas about one third remained slow, being re-innervated by the slow-type motor fibres of the implanted nerve.
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  • 85
    ISSN: 1432-1106
    Keywords: Cell cultures ; Fetal ; Hypothalamus ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Dissociated fetal hypothalamic cells mainly taken from 14 day-old mouse fetuses were grown in vitro for increasing time (9 to 60 days). Soon after inoculation the cells partly reaggregated and attached. The small reaggregates were then interconnected by fibers bundles. After the first week the cultures were composed of a continuous basal monolayer of flat and transparent cells, over which various types of refractile cells were lying in discontinuous areas. The ultra-structural study enabled us to identify these cell types, to describe their spatial relationships, and to follow their evolution with time in culture. The basal cell formed several superimposed layers. With increasing age, they displayed typical features of astrocytes and of ependymal cells. The latter exhibited rhythmic ciliary movements in culture. The overlying cells corresponded to three types which were associated in small clumps: primitive neuro-epithelial cells, maturing as well as mature neurons and typical neurosecretory cells. The latter cells were found as early as 9 days of culture of 14 day-old fetal hypothalamic cells and retained their typical features up to two months. Neuronal processes formed very dense networks at the surface of the cultures and terminated within the basal layers. Axon and dendrites were precociously found and were still present after two months. Within axon terminals dense-core vesicles appeared at the same time as neurosecretory cells. Synaptic vesicles and synaptic junctions were found later on.
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    Journal of neurology 210 (1975), S. 191-198 
    ISSN: 1432-1459
    Keywords: Pallidumdegeneration ; Bielschowsky bodies ; Lafora bodies ; Corpora amylacea ; Ultrastructure ; Torsion dystonia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei einem 60 Jahre alt gewordenen Mann, mit einer bis in die Kindheit zurückreichenden und extrem langsam progredienten, wahrscheinlich torsionsdystonischen bzw. choreoathetoiden Bewegungsstörung, fand sich eine isolierte Degeneration des äußeren Pallidumgliedes mit intraneuronaler Ablagerung von Bielschowsky-Körperchen und nur geringgradigem Nervenzellausfall. Die Bielschowsky-Körperchen zeigen den gleichen Aufbau wie Corpora amylacea und Lafora-Körperchen. Sie dürften ebenfalls Produkt einer cellulären, vorwiegend den Kohlenhydrat-stoffwechsel treffenden Dysmetabolie sein, die allerdings hier exquisit systembezogen auf die Neurone des äußeren Pallidumgliedes begrenzt ist und erst sehr spät bei fortgeschrittener Stapelung der Metabolite zum Untergang der Nervenzellen führt. Dieser Umstand erklärt den überaus torpiden Verlauf der Erkrankung.
    Notes: Summary In a 60-year-old man with a very slowly progressive motor disturbance probably of torsion dystonic or choreoathetotic type which started in childhood, we found an isolated degeneration of the exterior pallidum with intraneuronal deposition of Bielschowsky bodies and only slight deficit of neurons. The Bielschowsky bodies show the same structure as corpora amylacea and Lafora bodies. They might also be the result of a cellular disturbance mainly concerning the carbohydrate metabolism. In this case they are localised only in the neurons of the exterior part of the pallidum—in contrast to the organogenitically otherwise deriving (from the nuel. entopeduncularis) intact neurons of the pallidum internum—and they induce, after an excessive accumulation of the metabolites, not till extremely late loss of neurons. This circumstance explains the very torpid progress of this disease.
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    Journal of neurology 211 (1975), S. 61-68 
    ISSN: 1432-1459
    Keywords: Niemann-Pick ; Liver ; Sural nerve ; Ultrastructure ; Lipids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Das klinische, biochemische und ultrastrukturelle Bild einer Sphingolipidose vom Typ Niemann-Pick wurde an Hand eines Patienten mit der infantilen Form (A) dargestellt. Die Diagnose wurde klinisch auf Grund einer rasch progredienten psychomotorischen Retardation mit Hepatosplenomegalie sowie typischen Schaumzellen im Knochenmark gestellt und durch den Nachweis von exzessiver Speicherung von Sphingomyelin in einer Leberbiopsie und das Fehlen der Sphingomyelinase bestätigt. Ultrastrukturell konnte eine Anhäufung von präsumptiven Phospholipiden in den Lysosomen von Leber und peripherem Nerv festgestellt werden. Obwohl weder eine axonale Degeneration noch eine Demyelinisierung im biopsierten Nerv gefunden werden konnte, war die Nervenleitgeschwindigkeit in den peripheren Nerven beim Patienten schon bei der Diagnosestellung deutlich herabgesetzt. Die Bedeutung der Befunde wurde diskutiert.
    Notes: Summary A diagnosis of Niemann-Pick disease type A was made in a 6-month-old boy on the grounds of progressive psychomotor retardation, hepatosplenomegaly, typical foam cells in the bone marrow and a deficiency of sphingomyelinase in a liver biopsy. Typical ultrastructural changes in lysosomes were found in hepatocytes and in Schwann cells. In spite of the absence of gross morphological changes in the axons and in the myelin sheath of the peripheral nerve biopsy, the nerve conduction velocity in the patient was greatly reduced. The ultrastructural aspect of the lysosomal inclusion suggested the storage of a phospholipid. Biochemical analysis of the liver biopsy demonstrated an increased content of total phospholipid of which sphingomyelin made up for more than 60%. The significance of these data are discussed.
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    Archives of microbiology 102 (1975), S. 95-101 
    ISSN: 1432-072X
    Keywords: Coelastrum ; Chlorococcales ; Chlorophyta ; Ultrastructure ; Cell Wall ; Tubules ; Bristles ; Polymorphism ; Buoancy ; Taxonomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé La paroi cellulaire de Coelastrum est généralement composée de trois couches. La couche la plus externe a été plus particulièrement étudiée. Elle est composée de tubules dressées, et porte souvent de longues fibrilles dont le rôle serait de stabiliser l'algue dans son milieu. La morphologie de la paroi cellulaire peut se modifier en fonction du milieu.
    Notes: Abstract The cell wall of Coelastrum is usually composed of three layers. The outermost layer was studied most extensively. It consists of erect tubules which often bear long bristles whose function may be to stabilize the algae in its environment. The cell wall can modify its morphology according to the environment.
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    Archives of microbiology 102 (1975), S. 129-137 
    ISSN: 1432-072X
    Keywords: Diazepam ; Benzodiazepines ; Scenedesmus ; Ultrastructure ; Photosynthesis ; Respiration ; Rubidium Uptake
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Effects of diazepam (Valium) on photosynthesis, chlorophyll/photosynthesis ratios, respiration, uptake of rubidium ions, and ultrastructure of Scenedesmus obliquus synchronized by a light-dark regimen of $$14:\overline {10}$$ hrs were determined. 80 and 160 μM diazepam, added to the nutrient medium at the start of the light-dark change (i.e., start of the cell cycle) gradually reduced rates of photosynthesis below the initial rates from the beginning of the experiment. Contents of chlorophyll, however, remained nearly unaffected. Consequently, the diazepam-treated cells had a higher chlorophyll/photosynthesis ratio—also with regard to respiration in order to calculate the gross photosynthesis. The occurrence of photorespiration cannot be assumed. The net influx or rubidium was slightly reduced by 100 μM diazepam 0.5 and 2.0 hrs after the start of the cell cycle and was strongly inhibited after 5 to 14 hrs. 80 and 160 μM diazepam caused separation of thylakoids, formation of giant mitochondria and enlargement of vacuoles. The results are discussed and it is finally suggested that diazepam acts on different membrane systems. Furthermore an ATP deficiency cannot be excluded.
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  • 90
    ISSN: 1432-072X
    Keywords: Bacillus acidocaldarius ; Spores ; Germination ; Thermophile ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Spores of the thermophilic, acidophilic, Bacillus acidocaldarius were covered by a thick outer coat and a laminated inner coat (5.5 nm periodicity). Small membranous vesicles were present in the spore core and they disappeared as germination proceeded. After depolymerization of the cortex, and a 30% increase in spore diameter, a localized gap appeared in the laminated inner coat only. This inner coat gap was narrow and could be the whole length of the spore. The germ cell appeared to grow, or to be pushed towards the inner coat gap, at which stage the outer coat disappeared in the same localized area. As the vegetative cell grew out the spore coat fell away, with loose cortical material still attached to it. The young germ cell developed a large spherical electron dense inclusion body in the cytoplasm, at the same time as the ribosomal and nuclear areas became distinct.
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    Archives of microbiology 104 (1975), S. 271-277 
    ISSN: 1432-072X
    Keywords: Protoplasts ; Regeneration ; Wall Structure ; Pullularia ; Ultrastructure ; Membrane Splitting ; Aberrant Tubes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract During the process of degradation of the cell wall of the yeast form of Pullularia pullulans by the lytic system of Micromonospora chalcea samples were withdrawn at different times and observed under phase contrast and electron microscope. The progressive lysis of the walls reveals a fibrillar component inside the apparently amorphous wall. Freeze etched preparations of cells during the formation and regeneration of protoplasts show that the cellular membrane is split and this method allows the smooth external face of the membrane and other internal face covered by particles to be seen. The fact that the smooth face of the membrane is only visible during the preparation or the regeneration of protoplasts and very rarely when intact cells are fractured, suggests a strong adherence between cell wall and this external layer of the membrane. During the regeneration which takes place as in most of the yeasts and moulds, a special study of the extension of the cell wall is made and a possible mechanism for this extension of the regenerated cell wall is proposed.
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    Archives of microbiology 106 (1975), S. 209-214 
    ISSN: 1432-072X
    Keywords: Cyanobacteria ; Colonial sheath ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The colonial sheath of Microcystis marginata has a definite structure as seen by light and electron microscopy, consisting of a relatively smooth inner surface and densely packed, long fibrils on the outer surface. The sheath initially forms around the single cell and expands by continual deposition of sheath material to accomodate the synchronously dividing cells of the colony.
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  • 93
    ISSN: 1432-0878
    Keywords: Sympathetic ganglia ; Nerve growth factor ; Enzyme induction ; Ultrastructure ; Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Nerve cells of the superior cervical ganglion of young rats (20 g body weight) were investigated electron microscopically 6 h, 24 h, 48 h and 5 days after subcutaneous injection of nerve growth factor (10 μ/g body weight every 24 h). By means of a planimetric method with high accuracy significant changes of the Nissl substance and the Golgi apparatus could be demonstrated as early as 6 h after injection. Within the Nissl bodies both the density of bound ribosomes on the cisternae of the rough endoplasmic reticulum and the density of free ribosomes and polysomes decreased in a given field. This finding reflects a rearrangement of the Nissl substance and a spreading over larger areas of the cytoplasm, indicating an activation of the ribosomal system. The Golgi apparatus, in particular its outer part, increases in volume with time of nerve growth factor treatment. On the other hand, the total cell volume does not show significant changes before 48 h of nerve growth factor treatment. At this time an increase in the cytoplasmic volume can be seen, whereas the nuclear volume remains unchanged. The possibility of correlations of the present findings with data from biochemical studies done under similar experimental conditions is discussed.
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  • 94
    ISSN: 1432-0878
    Keywords: Neuromuscular junctions ; Rete synapticum ; Development ; Antheraea ; (Lepidoptera) ; Trophic action ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of neuromuscular connections on developing dorsolongitudinal flight muscles was studied in the moth Antheraea polyphemus, Undifferentiated membrane contacts between axon terminals and muscle-fiber anlagen are present in the diapause pupa. They persist during the period of nerve outgrowth, which probably provides a pathway of contact guidance. By the 4th day of adult development some of these contact areas have differentiated into structures similar to neuromuscular junctions although differentiation of muscle structure does not start earlier than the eighth day. Dense-cored vesicles are abundant in many axon terminals at the beginning of development. They later decrease in number quite rapidly. The significance of the above-mentioned early junctions, their possible mode of action and the role of the dense-cored vesicles are discussed. It is proposed that they exercise a stimulating (trophic) influence on the growth of the undifferentiated muscular tissue. The imaginai neuromuscular junctions are formed during the second half of adult development. Clusters of vesicles and electron-dense depositions along the inner face of the axolemma seem to initiate junction formation. Glial processes then grow between axoand sarcolemma and divide the large contact area into several small segments. Mutual invaginations and protrusions of the sarcolemma and the glial cell membrane subsequently form an extensive “rete synapticum.” Six days before eclosion the glial and sarcoplasmic parts of the rete synapticum are similar in size. Up to eclosion, all glial processes shrink and increase in electron density. Most of the observations are discussed also in relation to findings in vertebrates.
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  • 95
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    Cell & tissue research 159 (1975), S. 369-378 
    ISSN: 1432-0878
    Keywords: Crab muscle ; Excitation-contraction coupling ; Glycerol treatment ; Horseradish peroxidase ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of normal and glycerol treated fibers of the closer muscle of the ghost crab, Ocypode cursor, was studied. The muscle is composed of presumably phasic (short sarcomeres) and tonic (long sarcomeres) fibers, the latter greatly predominating. Horseradish peroxidase (HRP) was used as an extracellular tracer to delineate the tubular system (TS), and to determine to what extent this system becomes detached from the extracellular space as a result of glycerol treatment. Sarcolemmal clefts invade deeply into the muscle at Z-lines and I-bands; tubules invaginate into the muscle from the clefts and from the surface sarcolemma at the Z-lines, A-I overlaps and A-bands. A tubules are in frequent diadic or tetradic contact with the sarcoplasmic reticulum (SR), whereas Z tubules appear to be randomly associated with SR, terminal cisterns (TC) and Z-line fibrils. When HRP was administered to normal muscle, black reaction product was found adjacent to the outer surface of the sarcolemma, within the clefts and within profiles of the TS throughout the tissue. In glycerol treated muscle peripheral vacuolation frequently occurred; black reaction product penetrated only as far as the vacuoles and into dilated Z-line tubules, but was virtually absent from the rest of the TS. This lack of continuity between the extracellular space and the A tubules indicated disruption or constriction of the A tubules as a result of glycerol treatment, although Z tubule contact with the extracellular space appeared unimpaired. These findings provide ultrastructural correlates of the electrophysiological changes produced by glycerol treatment of the closer muscle of the ghost crab (Papir, 1973), namely, interference with excitation-contraction (e-c) coupling. The random association of the Z tubules with SR and TC, and their resistance to disruption by glycerol treatment, tend to endorse the claims that the Z tubules in crustacean muscle are not directly involved in e-c coupling (Brandt et al., 1965; Peachey, 1967; Selverston, 1967).
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  • 96
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    Cell & tissue research 159 (1975), S. 399-412 
    ISSN: 1432-0878
    Keywords: Porcellidium (copepode) ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Deux espèces de Porcellidium ont été examinées en microscopic à balayage et sur coupe avec les techniques habituelles (P. viride provenant de Banyuls-sur-mer, Méditerranée et P. fimbriatum de Roscoff, Manche; ces deux espèces vivent sur les Algues vertes du genre Ulva). Nous avons retrouvé les ultrastructures classiques de la cuticule, observées dans les principaux groupes de Copépodes. Quatre caractères nouveaux distinguent la cuticule dorsale des Porcellidium: 1. Différenciation d'un système de microvillosités externes, avec un niveau dense aux électrons, très contrasté par rapport aux extrémités d'où semblent partir de fins filaments englobant une population assez dense de Bactéries. 2. Cette plage de microvillosités recouvre un relief assez particulier de la procuticule, évoquant par ses cratères un paysage lunaire. 3. Présence de canaux cytoplasmiques ramifiés et terminés par une expansion arrondie, sous l'épicuticule. 4. Existence d'un système de vésicules reliant la base des microvillosités aux extrémités renflées des canaux cytoplasmiques. L'association des Bactéries est régulière et une grande proportion de celles-ci est en cours de cytolyse. La système de microvillosités et de canaux ne nous parait pas étranger à la présence de cette population bactérienne.
    Notes: Summary Two species of Porcellidium have been studied by scanning and transmission electron microscopy: P. viride from Banyuls-sur-mer, Mediterranian Sea and P. fimbriatum from Roscoff, English Channel. Both species live on green Algae of the genus Ulva. We confirmed previous descriptions of the cuticular ultrastructure in the main groups of Copepods. Four new characteristics however were shown to occur in the backcuticle of Porcellidium: 1. The presence of a system of highly differentiated external microvilli showing electron dense basal portions and less electron dense tips, from which thin filaments project towards a large population of Bacteria associated with the Copepod. 2. The surface of the cuticle resembles a lunar landscape with craters. The sheet of microvilli closely follows the contour of the cuticle. 3. The presence of branched cytoplasmic canals with swollen extremities (beneath the epicuticle) extending from the epidermal cells. 4. Systems of vesicles lying between the bases of the microvilli and the expansions (ampullae) at the tip of the cytoplasmic canals. The association of Bacteria with the cuticle is constant and many of these are apparently undergoing cytolysis. The system of microvilli and of cytoplasmic canals are apparently related to the presence of the bacterial microflora.
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  • 97
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    Cell & tissue research 159 (1975), S. 541-550 
    ISSN: 1432-0878
    Keywords: Testis ; Budgerigar ; Photoperiod ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Spermatogenesis in the Budgerigar can be arrested by reducing the birds' photoperiod to 8 hours of daylight or less. When this occurs, Sertoli cell cytoplasm shows a great increase in the size and number of residual bodies, while the smooth endoplasmic reticulum is reduced. If the bird is kept at 8 hours of daylight for some weeks large lipid droplets are seen in Sertoli cytoplasm, and degenerated spermatids are apparently phagocytosed. The interstitium shows fewer active Leydig cells, a paucity of lipids and occasional ovoid mitochondria. The basal lamellae of the tubule which are thick and convoluted before and during spermatogenesis become thinner and straighter. It is thought that these morphological changes reflect changes in metabolic activity.
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  • 98
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    Cell & tissue research 159 (1975), S. 551-561 
    ISSN: 1432-0878
    Keywords: Neurohypophysis, rat ; Exocytosis ; Blood vessels ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neural lobes of rats subjected to dehydration by drinking 2% saline for four days were examined electron microscopically and compared to untreated controls. The ultrastructure of the blood vessels and the tissues surrounding them were examined and it was found that, although few exocytotic figures could be seen in either group of animals, a significantly larger (P〈0.01) number of small vesicles were found in nerve endings adjacent to the perivascular space in the saline treated group when compared to nerve endings not closely associated with blood vessels. No differences were found in the control group of animals, which supports the suggestion that the vesicles could arise from a membrane recapture process.
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  • 99
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    Cell & tissue research 161 (1975), S. 167-176 
    ISSN: 1432-0878
    Keywords: Sphincter Oddi (Dog) ; Innervation ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure and acetylcholinesterase activity of the intrinsic innervation of the sphincter of Oddi of eight adult dogs was studied by electron microscopy. A rich distribution of unmyelinated axons embedded individually or as groups within Schwann cell cytoplasm (“innervation fasciculée”), is to be observed. A few myelinated fibres were also observed. Many of the axons are acetylcholinesterase-positive. Three main types of nerve terminals are distinguished according to their vesicle populations. Individual nerve cells or small groups of nerve cells were scattered between the smooth muscle bundles and in the lamina glandularis mucosae. The cytoplasm of some neurons contains many electron dense spherical bodies resembling “myeloid bodies”, and many lysosomes. Nerve terminals synapse onto both neuronal perikarya and their dendrites. Within the nerve fascicles, close appositions between the terminals occur frequently probably representing the most peripheral inter-neuronal integrative link in the neural regulation of the function of the sphincter of Oddi. — The gap between nerve terminals and smooth muscle cells usually measures several thousands of Å. Closer appositions are seldom seen, and no synaptic complexes can be observed.
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  • 100
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    Cell & tissue research 161 (1975), S. 413-419 
    ISSN: 1432-0878
    Keywords: Rectal papilla ; Insects ; Hymenoptera ; Cell Types ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the rectal papillae of the parasitoid hymenopteran, Nasonia vitripennis (Walk), is described. These organs in this insect consist of four distinct cell types arranged as a closed, hollow cone. The majority of the cells are present in the raised cone, and are characterised by large numbers of mitochondria arranged in a membranous labyrinth. A series of cells form a collar around the base of the cone. Junction cells have been identified which are present at the point of insertion of the cone into the rectal epithelium. The base of the cone consists of cells with elaborately folded plasma membranes facing both the central cavity of the cone, and the haemolymph. The structure of this rectal papilla is compared with those found in other insects.
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