ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Scanning electron microscopy  (77)
  • Saccharomyces cerevisiae
  • Springer  (111)
  • American Institute of Physics (AIP)
  • 1975-1979  (111)
Collection
Keywords
Publisher
  • Springer  (111)
  • American Institute of Physics (AIP)
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    Altered patterns of protein synthesis induced by heat shock of yeast (1979)
    Springer
    Current genetics 1 (1979), S. 63-74 
    Details
    ISSN: 1432-0983
    Keywords: Saccharomyces cerevisiae ; Translation ; Coordinate regulation ; Electrophoresis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The products of protein synthesis from exponential phase cultures of Saccharomyces cerevisiae grown at 23 °C or at 36 °C appear to be essentially identical. However, yeast cells respond to a shift in culture temperature from 23 °C to 36 °C with the rapid de novo synthesis of a polypeptide species of molecular weight 100,000. Within 60–90 min after the shift this polypeptide represents approximately 2.5% of the total cellular protein, a 5–10 fold increase over the preshift level. The level of this polypeptide then decreases with continued growth of the cells at 36 °C. Analyses by SDS-polyacrylamide gel electrophoresis of polypeptides obtained from cells pulse labeled with [35S]methionine demonstrate that following a temperature shift from 23 °C to 36 °C the synthetic rate of the 100,000 molecular weight polypeptide (as well as a number of other polypeptide species) increases to a level at least 10 fold higher than that observed prior to the shift. A concomittant decrease is observed in the synthesis of a large number of polypeptide species which were actively synthesized before the shift. Maximum changes in synthetic rates are observed 20–30 min after the shift and preshift synthetic patterns are regained within 60–90 min. Synthetic changes of the same magnitude and time course can be produced by short (20–30 min) exposures to 36 °C implicating a heat shock response. Several of the transiently induced polypeptides, including the 100,000 molecular weight species, show an affinity for DNA as determined by DNA-cellulose chromatography.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00413307
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    SEM analysis of amphibian mesodermal migration (1977)
    Springer
    Development genes and evolution 181 (1977), S. 31-40 
    Details
    ISSN: 1432-041X
    Keywords: Cell migration ; Mesoderm ; Gastrulation ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary At the end of gastrulation, the lateral mesoderm of amphibian embryos migrates ventrally between the ectoderm and the endoderm. The present study is an examination of the morphology of the leading cells of the mesodermal sheet and of the substratum over which they move (the inner surface of the ectoderm). The cells of the leading edge of the mesoderm are generally round, with very short and narrow flattened projections in the forward direction. These projections do not have a “ruffled” morphology, regardless of whether fixation is carried out before or after the ectoderm and mesoderm are dissected away from the endoderm. The inner surface of the ectoderm is covered with fine (450–500A) filamentous extracellular material and the ectoderm cells sometimes extend cytoplasmic processes (approx. 0.1 μ wide) onto the leading surface of the mesoderm or onto adjacent ectoderm cells. These studies indicate that the morphology of cell migration in amphibians is closer to that seen inFundulus than to that characteristic of chick or mammalian cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00857266
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Growth of embryonic chick tibiae in ovo and in vitro: A scanning electron microscope study (1979)
    Springer
    Calcified tissue international 27 (1979), S. 33-40 
    Details
    ISSN: 1432-0827
    Keywords: Chick embryo ; Bone ; Organ culture ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The study describes the ultrastructure of the mineralized portion of chick tibiae from 10 days in ovo to 2 days post-hatch. At 10 days a single mineralized cylinder surrounds the diaphysis. On its outer surface columnar trabeculae join to form ridges parallel to the long axis of the bone. These ridges are covered by another cylinder and form the haversian canals. At 11 days vascular invasion of the marrow cavity occurs and resorption of the endosteal surface begins. This type of periosteal deposition and endosteal resorption is repeated during and subsequent to embryonic development. The mineralized portion of 10-day chick tibiae cultured for 2 days in modified BGJ medium was compared with 10-, 11-, and 12-day tibiae in ovo. Cultured tibiae were similar in length and calcium content to 11-day tibiae in ovo. The form of mineral deposited in ovo and in culture was the same, namely, aggregates of spherical mineral clusters. Differences in culture included the following: (a) few concentric cylinders were deposited as compared with tibiae in ovo; (b) trabeculae were not arranged in rows and ridges in culture; (c) osteocytic lacunae were restricted to bases of trabeculae rather than uniformly distributed as in ovo; and (d) the endosteal surface of tibiae in culture appeared etched.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02441158
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Correlation of freeze-fracture and scanning electron microscopy of epiphyseal chondrocytes (1978)
    Springer
    Calcified tissue international 26 (1978), S. 237-241 
    Details
    ISSN: 1432-0827
    Keywords: Epiphyseal chondrocytes ; Freezefracture ; Scanning electron microscopy ; Cell processes ; Membrane particles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Chondrocytes in epiphyseal cartilage were examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) using freeze-fracture techniques. Freeze-fracture replicas showed large numbers of fingerlike, 0.11–0.15 μm diameter, projections from the chondrocyte surface, with numerous 95–180 Å diameter intramembranous particles associated with both the cell membrane surface and these projections. With SEM, these cytoplasmic projections were also obvious, but appeared collapsed into clusters of globular-shaped projections on the surface of the chondrocytes. With freeze-fracture techniques, in which shrinkage artifacts were essentially eliminated, the cytoplasmic projections were often seen in intimate contact with the extracapsular matrix. However, with chondrocytes prepared by both SEM and conventional TEM, there was evidence of shrinkage, the cytoplasmic projections having little contact with the extracapsular matrix. These findings show that the cytoplasmic processes are not artifacts of tissue processing and provide morphological evidence in support of the hypothesis that matrix vesicles are of cellular origin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02013264
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Scanning electron microscopical study on the fluorosis of enamel in rats (1978)
    Springer
    Calcified tissue international 25 (1978), S. 75-83 
    Details
    ISSN: 1432-0827
    Keywords: Rat ; Fluorosis ; Enamel ; Scanning electron microscopy ; Low temperature incineration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Sixteen 58-day-old male rats of Wistar strain, with a mean body weight of 179 g, were divided into two equal groups. Each group of eight animals was maintained for 70 days on drinking water, ad lib., containing no fluorine (control group) and 100 ppm of fluorine (experimental group). All specimens examined were obtained from the incisal portions of the incisors. The following types of enamel specimens were prepared for scanning electron microscopy: (1) acid-etched specimens; (2) acid-etched specimens followed by low temperature microincineration; and (3) fractured specimens. The enamel formed during high fluoride exposure showed marked hypocalcification, that is, the crystallite density in the prism core and interprismatic region was lower than that of control animals. The organic substances appeared to increase in these regions. These changes were prominent in the outer and middle enamel layers. Such changes following fluoride administration appear to indicate an inhibition of enamel maturation, that is, an inhibition of the mineral deposition and/or an inhibition of organic matrix withdrawal.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02010754
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Structure and association of wall fibrils produced by regenerating tobacco protoplasts (1979)
    Springer
    Planta 146 (1979), S. 203-210 
    Details
    ISSN: 1432-2048
    Keywords: Cellulose ; Microfibrils ; Negative staining ; Nicotiana ; Protoplasts ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A study has been made of the wall fibrils produced by tobacco protoplasts, using scanning electron microscopy in conjunction with negative staining. It has been shown that the fibres seen in scanning electron microscopy correspond to aggregates of microfibrils. These aggregates are only visible where they are lifted clear of the protoplast surface. Negative staining of fixed protoplasts shows that the aggregation of microfibrils into the fibres visible in scanning electron microscopy is probably produced by air-drying. Gentle disruption of microfibrils produces both random broken fragments and bundles of short pieces of fibrillar material about 60 nm in length. This material is present in undisrupted young walls, but not in undisrupted older walls. The microfibrils in young walls seem much more fragile and liable to breakage than those in older walls. These results are discussed in terms of the interpretation of scanning electron microscope images and the mechanism of cellulose microfibril formation by higher plants.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00388233
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Free tryptophan pool and tryptophan biosynthetic enzymes in Saccharomyces cerevisiae (1976)
    Springer
    Archives of microbiology 107 (1976), S. 207-214 
    Details
    ISSN: 1432-072X
    Keywords: Anthranilate synthase ; Cell permeabilisation ; Indoleglycerolphosphate synthase ; Saccharomyces cerevisiae ; Tryptophan biosynthetic enzymes ; Tryptophan pool
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The free tryptophan pool and the levels of two enzymes of tryptophan biosynthesis (anthranilate synthase and indoleglycerolphosphate synthase) have been determined in a wild type strain of Saccharomyces cerevisiae and in mutants with altered regulatory properties. The tryptophan pool of wild type cells growing in minimal medium is 0.07 μmole per g dry weight. Addition of anthranilate, indole or tryptophan to the medium produces a fifteen- to forty-fold increase in tryptophan pool, but causes no repression of the biosynthetic enzymes. Inclusion of 5-methyltryptophan in the growth medium causes a reduction in growth rate and a derepression of the biosynthetic enzymes, and this is shown here not to be correlated with a decrease in the free tryptophan pool. Mutants with an altered anthranilate synthase showing decreased sensitivity to inhibition by l-tryptophan or by the analogue dl-5-methyltryptophan have a tryptophan pool far higher than the wild type strain, but no repression of indoleglycerolphosphate synthase was observed. Mutants with an anthranilate synthase more sensitive to tryptophan inhibition show a slightly reduced tryptophan pool, but no derepression of indoleglycerolphosphate synthase was found. A mutant with constitutively derepressed levels of the biosynthetic enzymes shows a considerably increased tryptophan pool. Addition of 5-methyltryptophan to the growth medium of non-derepressible mutants causes a decrease in growth rate accompanied by a decrease in the tryptophan pool.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446842
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Some physiological observations on the uptake of d-glucose and 2-deoxy-d-glucose by starving and exponentially-growing yeasts (1976)
    Springer
    Archives of microbiology 111 (1976), S. 185-192 
    Details
    ISSN: 1432-072X
    Keywords: Yeasts ; Sugars ; d-Glucose ; 2-Deoxy-d-glucose ; Pichia pinus ; Transport ; Starvation ; Exponential growth ; Methodology ; Candida utilis ; Saccharomyces cerevisiae ; Rhodosporidium toruloides
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Some methods for measuring the uptake of sugars by yeasts were investigated critically. A study was made of the effects of starvation of Pichia pinus, Candida utilis, Saccharomyces cerevisiae and Rhodosporidium toruloides on their uptake of d-glucose and 2-deoxy-d-glucose. Marked changes in the rates of uptake of these sugars occurred during 10 h of starvation, including (a) an immediate increase of up to 75% above that for growing cells and (b) a continuous decline to as little as 4%. Each yeast behaved differently. The rates did not remain constant during the periods of starvation often used for studies on the transport of sugars into yeasts. For Pichia pinus, there were striking differences, associated with starvation, between the transport of 2-deoxy-d-glucose and d-glucose, despite evidence that the two sugars enter this yeast by means of the same carrier. Some physiological explanations for these findings are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446567
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Localization of α-galactomannan on the surface of Schizosaccharomyces pombe cells by scanning electron microscopy (1977)
    Springer
    Archives of microbiology 112 (1977), S. 123-126 
    Details
    ISSN: 1432-072X
    Keywords: Bandeiraea simplicifolia ; Schizosaccharomyces pombe ; Colloidal gold ; Cytochemistry ; α-Galactomannan-lectin ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Galactomannan was localized by scanning and transmission electron microscopy on the cells and cell walls of Schizosaccharomyces pombe. The markers were prepared from colloidal gold granules labelled with an α-galactopyranosyl-binding lectin isolated from the seeds of Bandeiraea simplicifolia. Part or all of this α-galactomannan was present in the outer layer of the cell wall and was uniformly distributed even on the fission scars.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00429323
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    In vivo and in vitro studies on the glucose dependent inactivation of yeast cytoplasmic malate dehydrogenase (1977)
    Springer
    Archives of microbiology 115 (1977), S. 55-60 
    Details
    ISSN: 1432-072X
    Keywords: Malate dehydrogenase ; Inactivation ; Glucose metabolism ; Glyceraldehyde-3-phosphate ; Saccharomyces cerevisiae ; Glyoxylate cycle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The cytoplasmic malate dehydrogenase in the yeast Saccharomyces cerevisiae is known to be inactivated by a glucose dependent process. In this paper it is shown that in vivo effectors of the glucose metabolism (arsenate, iodoacetate, acetaldehyde) inhibit the inactivation or change the inactivation kinetics. In vitro it was possible to inactivate the malate dehydrogenase by addition of the glucose metabolite glyceraldehyde 3-phosphate. The physiological relevance of this modification and the effect of malate dehydrogenase inactivation on the glyoxylate cycle in yeast is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00427845
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    In situ study of the glycolytic pathway in Saccharomyces cerevisiae (1978)
    Springer
    Archives of microbiology 117 (1978), S. 197-201 
    Details
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Glycolytic pathway ; Fermentation rate ; Protein concentration ; Kinetic parameters ; Glycolytic enzymes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 1. The problem of the influence of protein concentration on the kinetic parameters of enzymes has been approached studying the glycolytic enzymes from Saccharomyces cerevisiae in permeabilized cells (in situ). 2. The values of K m and V max for the different enzymes were essentially the same in dilute solutions of protein and in concentrated ones (in situ) except in the case of enolase where some differences were observed. 3. Functioning of the whole glycolytic pathway was compared in situ and in vitro measuring the rate of the fermentation of glucose. The rate of fermentation in situ was two fold higher than in vitro and the lag before active fermentation was also much shorter. 4. An unidentified phosphorylated compound, possibly polyphosphate, accumulates during the fermentation of glucose under in situ conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00402308
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Toxicity and accumulation of thallium in bacteria and yeast (1976)
    Springer
    Archives of microbiology 110 (1976), S. 279-286 
    Details
    ISSN: 1432-072X
    Keywords: Thallium accumulation ; Saccharomyces cerevisiae ; Escherichia coli ; Bacillus megaterium KM ; Thallium toxicity ; Potassium ; Microbial growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Thallium sulphate inhibited microbial growth, withBacillus megaterium KM, more sensitive to the metal thanSaccharomyces cerevisiae andEscherichia coli. Inhibition ofB. megaterium KM andS. cerevisiae, but not ofE. coli, was alleviated by increasing the potassium concentration of the medium; inhibition of respiration ofS. cerevisiae, but not ofE. coli, was similarly alleviated. Thallium was rapidly bound, presumably to cell surfaces, byS. cerevisiae andE. coli, and was progressively accumulated by energy-dependent transport systems (probably concerned primarily with potassium uptake) with both organisms. Thallium uptake kinetics suggested more than one transport system operated in yeast, possibly reflecting a multiplicity of potassium transport systems. ApparentK m andK i values for competitive inhibition of thallium uptake by potassium indicatedS. cerevisiae to have a higher affinity for thallium uptake than for potassium, whileE. coli had a transport system with a higher affinity for potassium than for thallium. The likely systems for thallium transport are discussed. A mutant ofE. coli with tenfold decreased sensitivity to thallium was isolated and apparently effected surface binding of thallium in amounts equivalent to the wild type organism, but showed no subsequent uptake and accumulation of the metal from buffer, even though it was able to accumulate potassium to normal intracellular concentrations during growth.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00690239
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Correlation among turnover of nucleic acids, ribonuclease activity and sporulation ability of Saccharomyces cerevisiae (1976)
    Springer
    Archives of microbiology 111 (1976), S. 13-19 
    Details
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Sporulation ; Ribonuclease ; Turnover of nucleic acids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The turnover of nucleic acids and changes in ribonuclease activity during sporulation of Saccharomyces cerevisiae were studied. In the sporulating strains, 37–58% of vegetatively synthesized RNA were degraded during the sporulation process. The degree of degradation of vegetative RNA was proportional to the sporulation ability. In the non-sporulating strains, the degradation of vegetative RNA was less than 28% in the sporulation medium. Accompanied by the degradation of vegetative RNA, a ribonuclease activity increased several times during sporulation. We have found a close relation among the sporulation rate, the degree of the degradation of vegetative RNA and the increase in ribonuclease activity in the sporulation medium, using cells of which sporulation ability was repressed by changing the age or carbon source in various degrees.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446544
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    Mating reaction in Saccharomyces cerevisiae (1976)
    Springer
    Archives of microbiology 108 (1976), S. 27-33 
    Details
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Mating reaction ; Sexual cell agglutination ; α substance-I ; Agglutination factor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A diffusible sex-specific substance called α substance-I (αS-I) was isolated from culture filtrate of α type strains of the yeast Saccharomyces cerevisiae. The isolated αS-I, an oligopeptide, induced sexual cell agglutinability in inducible a type strains and enhanced the agglutinability in constitutive a type strains. The induction of sexual agglutinability was detected in 30 min and reached maximum in 90 min, when 0.2 μg/ml of αS-I was added to inducible a type cells. The a type-specific factor responsible for sexual cell agglutination, called a type agglutination factor (aAF), was shown to be produced during the induction or the enhancement of agglutinability of a type cells by αS-I. The aAF produced in response to αS-I was not different in the susceptibility to proteolytic enzymes and disulfide-cleaving agents from those produced constitutively in the absence of αS-I.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425089
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    The formation of glycosidic bonds in yeast glycoproteins (1977)
    Springer
    Archives of microbiology 114 (1977), S. 77-81 
    Details
    ISSN: 1432-072X
    Keywords: Mannoproteins ; Dolichyl monophosphate mannose ; Subcellular site of glycosylation ; Secretion ; Saccharomyces cerevisiae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Membranes of Saccharomyces cerevisiae were separated on urografin gradients. The specific activity of the light membranes (endoplasmic reticulum), the Golgi-like vesicles and the plasma membrane in transferring mannosyl residues from GDP-mannose to mannoproteins and to dolichyl monophosphate has been determined. The first mannose of the O-glycosidically linked manno-oligosaccharides is incorporated with the highest specific activity by the endoplasmic reticulum. The incorporation of the second to fourth mannosyl groups is catalysed with increasing activity also by the Golgi-like vesicles and the plasma membrane. The incorporation of mannosyl groups into weak alkali-stable positions (N-glycosidically linked chains) is carried out with almost the same specific activity by all three membrane fractions, however, dolicholdependent and-independent steps could not be distinguished as yet. The results are discussed in terms of a sequential addition of sugar residues along the route of export of the mannoproteins. The dolichol-dependent steps seem to occur on the endoplasmic reticulum and thus very carly in the event.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00429634
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    The effect of aminopterin (4-amino folic acid) on growth and cell division of fermentative versus oxidative yeasts (1977)
    Springer
    Archives of microbiology 113 (1977), S. 293-302 
    Details
    ISSN: 1432-072X
    Keywords: Aminopterin ; Saccharomyces cerevisiae ; Polyploid ; Oxidative-fermentative yeast ; Ultrastructure ; Bioassay ; Synchrony
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In a related brewing study detailed characteristics of fermentations displaying effective yeastaminopterin interaction were presented. Fermentative yeast types (certain Saccharomyces species and Selenotila intestinalis) proved effective aminopterin reactors whereas oxidative yeasts (certain Candida, Cryptococcus, Pichia, Rhodotorula, Saccharomyces, and Trigonopsis species) proved ineffective reactors. In general effective reactors were polyploids characterized by the lack of film or pellicle formation and ineffective reactors the opposite. In stationary fermentations the Fleischmann 139 strain of S. cerevisiae proved a fair reactor. When aerated it proved an ineffective reactor and aminopterin or products there-of stimulated growth. Conversely aeration enhanced aminopterin activity of effective reactor yeasts. The positive effect of biotin on aminopterin activity and the negative effect of yeast extract, L-asparagine, adenine and thymine is shown and compared and contrasted with earlier reported studies. These findings supported by outside data suggest that oxidative yeasts (and bacteria) can readily elicit enzymes capable of inactivating aminopterin whereas fermentative types are lacking in this capability. Finally that past yeast-aminopterin studies were conducted with oxidative yeast types. Advantages of effective aminopterin reactor yeasts to be published elsewhere include improved ultrastructure using KMnO4−OsO4 fixation, a yeast bioassay procedure for detecting aminopterin in plasma and urine, and cell synchronization.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00492038
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    Environmentally-induced changes in the neutral lipids and intracellular vesicles of Saccharomyces cerevisiae and Kluyveromyces fragilis (1977)
    Springer
    Archives of microbiology 114 (1977), S. 137-142 
    Details
    ISSN: 1432-072X
    Keywords: Environment ; Kluyveromyces fragilis ; Lipids ; Saccharomyces cerevisiae ; Sterol esters ; Triacylglycerols ; Vesicles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Saccharomyces cerevisiae, grown aerobically or anaerobically under conditions which induce a requirement for a sterol and an unsaturated fatty acid, synthesized approximately the same amounts of neutral lipid and intracellular low-density vesicles, although the neutral lipids in aerobically-grown cells contained more esterified sterol and less triacylglycerol than those in anaerobically-grown cells. Kluyveromyces fragilis synthesized much less neutral lipid and a smaller quantity of low-density vesicles than S. cerevisiae whether grown at 30°C (generation time 1.1 h) or 20°C (generation time 2.1 h). Both yeasts synthesized highly saturated triacylglycerols, relatively unsaturated phospholipids, and esterified sterols with an intermediate degree of unsaturation irrespective of the conditions under which they were grown. Free sterols in the yeasts were rich in ergosterol and 22(24)-dehydroergosterol, while the esterified sterol fractions were richer in zymosterol.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00410774
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    The isolation and characterization of peroxisomes (microbodies) from baker's yeast, Saccharomyces cerevisiae (1975)
    Springer
    Archives of microbiology 105 (1975), S. 187-192 
    Details
    ISSN: 1432-072X
    Keywords: Peroxisomes (microbodies) ; Saccharomyces cerevisiae ; Catalase ; Urate oxidase ; Glyoxylate cycle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Peroxisomes were isolated from derepressed (lactose grown) Saccharomyces cerevisiae cells following homogenization with a “Merkenschlager” cell mill (at 0°C using glass beads). Catalase and urate oxidase, along with low activities of d-amino acid oxidase and l-α-hydroxyacid oxidase (glycollate oxidase), were associated with the peroxisomes. No catalase activity was present in glucose repressed cells. When protoplasts prepared from derepressed cells were used for peroxisome isolation, catalase activity was not sedimentable through gradients. Apparently peroxisomes were destroyed as the cells became fermentative during protoplast preparation. The distribution of glyoxylate cycle enzymes was examined. Isocitrate lyase was not sedimentable, suggesting that, if the enzyme is peroxisome-associated, it is either readily released or present in a labile second class of peroxisomes. Low activities of malate dehydrogenase and citrate synthetase were found in peroxisome fractions from gradients, but may represent mitochondrial contamination. Citrate synthetase was not found associated with a low-density particle as had been previously reported.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00447136
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Localization of mannan at the surface of yeast protoplasts by scanning electron microscopy (1976)
    Springer
    Archives of microbiology 109 (1976), S. 9-14 
    Details
    ISSN: 1432-072X
    Keywords: Candida utilis ; Saccharomyces cerevisiae ; Colloidal gold ; Cytochemistry ; Mannan ; Plasma membranes ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The β(1→3)glucanase of Basidiomycete QM 806 was used to prepare Saccharomyces cerevisiae and Candida utilis protoplasts. Plasma membranes isolated from S. cerevisiae contained a small amount of mannose and traces of glucose and ribose. Randomly distributed α-mannan was detected by scanning electron microscopy at the surface of prefixed protoplasts using colloidal gold labelled with Concanavalin A as a marker. C. utilis protoplasts were also marked with anti-mannan antibodies. Again the distribution of mannan was random. This experiment indicated also that plasma membrane mannan has the same immunochemical determinants as cell wall mannan. It is hypothesized that mannan is mainly located in the outer layer of plasma membranes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425106
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Mating in Chlamydomonas eugametos (1976)
    Springer
    Archives of microbiology 109 (1976), S. 31-35 
    Details
    ISSN: 1432-072X
    Keywords: Scanning electron microscopy ; Chlamydomonas ; Cell agglutination ; Cell fusion ; Flagella
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A technique has been developed by which mating gametes of Chlamydomonas eugametos can be studied in the Scanning Electron Microscope. A detailed description of the mating process, from the initial flagellar agglutination until the release of free vis-à-vis pairs, is presented. Flagella appear to agglutinate at random points on their surface. This is followed by a rapid increase of the contact area such that they “line-up” tip to tip. Flagella always exhibit a typical position prior to cell fusion. After cell fusion the flagella of a pair separate rapidly while the female have shortened about 33%. In a vis-à-vis pair the plasma bridge has contracted. The observations are interpreted in terms of a specific reorganization of the sexuale aggregate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425109
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    Inactivation by glucose of phosphoenolpyruvate carboxykinase from Saccharomyces cerevisiae (1976)
    Springer
    Archives of microbiology 109 (1976), S. 221-225 
    Details
    ISSN: 1432-072X
    Keywords: Phosphoenolpyruvate carboxykinase ; Inactivation ; Saccharomyces cerevisiae ; Carbohydrate metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Phosphoenolpyruvate carboxykinase showed high activity in Saccharomyces cerevisiae grown on gluconeogenic carbon sources. Addition of glucose to such cultures caused a rapid loss of the phosphoenolpyruvate carboxykinase activity. Fructose or mannose had the same effect as glucose, while 2-deoxyglucose or galactose were without effect. The inactivation was an irreversible process, since the regain of the activity was dependent of de novo protein synthesis. Cycloheximide did not prevent inactivation. All strains of the genus Saccharomyces tested showed inactivation of their phosphoenolpyruvate carboxykinase upon addition of glucose; this behaviour was not restricted to this genus.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446632
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    The influence of pH on sulphite formation by yeasts (1976)
    Springer
    Archives of microbiology 107 (1976), S. 229-231 
    Details
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; pH ; Sulphite formation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The influence of the initial pH of the substrate on the sulphite formation of three low-sulphite-and five high-sulphite-forming yeasts is described. Four distinctly different groups become apparent. The need for better evaluation of pure culture wine yeasts is stressed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446846
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    Location of three key enzymes of gluconeogenesis in baker's yeast (1977)
    Springer
    Archives of microbiology 113 (1977), S. 159-161 
    Details
    ISSN: 1432-072X
    Keywords: Baker's yeast ; Spheroplasts ; Gluconeogenesis ; Location ; Density gradient centrifugation ; Saccharomyces cerevisiae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The subcellular location of hexose diphosphatase, phosphoenolpyruvate carboxykinase and pyruvate carboxylase in baker's yeast (Saccharomyces cerevisiae) was investigated by density gradient centrifugation of spheroplast lysates obtained by osmotic shock treatment of spheroplasts and centrifugation for 10000 g x min. On the evidence obtained from zonal separations these three enzymes of gluconeogenesis are most probably located in the soluble cytosol.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00428597
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    Temperature-sensitive loss of sexual agglutinability in Saccharomyces cerevisiae (1977)
    Springer
    Archives of microbiology 114 (1977), S. 287-288 
    Details
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Mating reaction ; Sexual agglutination ; Temperature dependency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Temperature dependency of sexual agglutination in Saccharomyces cerevisiae was found. Of 31 strains tested, which showed normal agglutination when cultured at 25°C, 29 strains lost their sexual agglutinability when they were grown at 37°C.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446875
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    Effect of chemical modification of cell surface components of a brewer's yeast on the floc-forming ability (1977)
    Springer
    Archives of microbiology 115 (1977), S. 19-23 
    Details
    ISSN: 1432-072X
    Keywords: Yeast flocculation ; Chemical modification of cell surface components ; Floc-forming ability ; Brewer's yeast ; Saccharomyces cerevisiae ; Deflocculation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Effects of treatments with proteolytic enzymes and protein-modifying reagents on flocculation of brewer's yeast IFO 2018 were investigated. The floc-forming ability of the yeast cells was irreversibly eliminated by treatment with papain, trypsin, chymotrypsin or pepsin, indicating that certain proteins on the cell surface participate in the yeast flocculation. Chemical modification with reagents, known to act on disulfide bridges, carboxyl and/or phosphate groups, phenolic groups, amino groups, and imidazole groups, also destroyed the ability to flocculate, although in some cases a high concentration (8 M) of urea was necessary in addition to protein-modifying reagents. Thus, it is suggested strongly that these functional groups of amino acid residues of the proteins are essential for the floc-forming ability of brewer's yeast cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00427840
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    Plasma-Membrane lipid composition and ethanol tolerance inSaccharomyces cerevisiae (1978)
    Springer
    Archives of microbiology 117 (1978), S. 239-245 
    Details
    ISSN: 1432-072X
    Keywords: Plasma membrane ; Lipids ; Saccharomyces cerevisiae ; Ethanol tolerance ; Sterols ; Fatty-acyl residues
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Populations of cells suspended anaerobically in buffered (pH 4.5) M ethanol remained viable to a greater extent when their plasma membranes were enriched in linoleyl rather than oleyl residues irrespective of the nature of the sterol enrichment. However, populations with membranes enriched in ergosterol or stigmasterol and linoleyl residues were more resistant to ethanol than populations enriched in campesterol or cholesterol and linoleyl residues. Populations enriched in ergosterol and cetoleic acid lost viability at about the same rate as those enriched in oleyl residues, while populations grown in the presence of this sterol and palmitoleic acid were more resistant to ethanol. Suspending cells in buffered ethanol for up to 24 h did not lower the ethanol concentration.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00738541
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    Inhibitory effect of ethanol on growth and solute accumulation by Saccharomyces cerevisiae as affected by plasma-membrane lipid composition (1979)
    Springer
    Archives of microbiology 122 (1979), S. 49-55 
    Details
    ISSN: 1432-072X
    Keywords: Ethanol inhibition ; Solute accumulation ; Saccharomyces cerevisiae ; Plasma membrane ; Lipids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Incorporation of ethanol (1.0 or 1.25 M) into exponential-phase cultures of Saccharomyces cerevisiae NCYC 366 growing anaerobically in a medium supplemented with ergosterol and an unsaturated fatty acid caused a retardation in growth rate, which was greater when the medium contained oleic rather than linoleic acid. Ethanol incorporation led to an immediate drop in growth rate, and ethanol-containing cultures grew at the slower rate for at least 10 h. Incorporation of ethanol (0.5 M) into buffered (pH 4.5) cell suspensions containing d-[6-3H] glucose, d-[1-14C] glucosamine, l-[U-14C] lysine or arginine, or KH2 32PO4 lowered the rate of solute accumulation by cells. Rates of accumulation of glucose, lysine and arginine were retarded to a greater extent when cells had been grown in the presence of oleic rather than linoleic acid. This difference was not observed with accumulation of phosphate. Ethanol was extracted from exponential-phase cells by four different methods. Cells grown in the presence of linoleic acid contained a slightly, but consistently, lower concentration of ethanol than cells grown in oleic acid-containing medium. The ethanol concentration in cells was 5–7 times greater than that in the cell-free medium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00408045
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    Dependence of the maximum temperature for growth of Saccharomyces cerevisiae on nutrient concentration (1975)
    Springer
    Archives of microbiology 104 (1975), S. 23-28 
    Details
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Yeast ; Chemostat ; Nutrient Concentration ; Thermal Death ; Thermal Association ; Optimum Temperature for Growth ; Maximum Temperature for Growth ; Microbial Ecology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Saccharomyces cerevisiae was grown in a chemostat under glucose limitation at three superoptimal temperatures. In each steady state the specific growth rate was the sum of the dilution rate and the specific death rate, exponential death concurring with exponential growth. The specific death rate was a function of the temperature while the specific growth rate was a function of both the temperature and the concentration of the limiting nutrient. Each superoptimal temperature was characterized by a critical glucose concentration below which net growth was not possible. The critical glucose concentration increased with the temperature. Consequently the maximum temperature for growth was a function of the concentration of the limiting nutrient and approached the optimum temperature for growth with decreasing glucose concentrations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00447295
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    Effect of aeration on the activity of gluconeogenetic enzymes in Saccharomyces cerevisiae growing under glucose limitation (1975)
    Springer
    Archives of microbiology 106 (1975), S. 271-273 
    Details
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Baker's yeast ; Gluconeogenetic enzymes ; Chemostat ; Oxygen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 1. The effect of aeration on the key enzymes of gluconeogenesis was studied in baker's yeast (Saccharomyces cerevisiae) and in a nonrespiratory variant of S. cerevisiae grown under glucose limitation. 2. In baker's yeast phosphoenolpyruvate carboxykinase, hexosediphosphatase and isocitrate lyase were completely repressed under anaerobic conditions. Their repression could be partially reversed by using intense aeration. 3. In the nonrespiratory variant these enzymes were absent independently of aeration. 4. Pyruvate carboxylase of baker's yeast showed maximal activity under anaerobic conditions. In the nonrespiratory variant pyruvate carboxylase had low activity under both anaerobic and aerobic conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446534
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    Promotion of sporulation by caffeine pretreatment in Saccharomyces cerevisiae (1976)
    Springer
    Archives of microbiology 108 (1976), S. 149-152 
    Details
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Sporulation ; Ribonuclease ; Caffeine ; Cycloheximide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Changes in RNase activity during sporulation of a homothallic diploid strain of Saccharomyces cerevisiae were measured in caffeine-treated and non-treated cells. 1. In caffeine-treated cells soon after the transfer to the sporulation medium a significant increase in RNase activity was observed; in control cells the rise of RNase activity was less and started after a lag period of 5 h. The final activity of RNase was about twice as high in caffeine-treated cells as in control cells. 2. Increase in RNase activity during sporulation was sensitive to cycloheximide in control cells, but insensitive in caffeine-treated cells. 3. RNases from vegetative cells and from sporulating ones are different in their K m values. Relation of the changes in RNase activity to premeiotic DNA synthesis is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00428944
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    Electronic Resource
    Electronic Resource
    Thermodynamic compensation in microbial thermal death (1976)
    Springer
    Archives of microbiology 108 (1976), S. 293-298 
    Details
    ISSN: 1432-072X
    Keywords: Yeast ; Saccharomyces cerevisiae ; Maximum temperature for growth ; Thermal death ; Linear thermodynamic compensation ; Non-linear thermodynamic compensation ; Isokinetic temperature
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Sixty eight Arrhenius plots of thermal death in six mesophilic yeast species, tested at various concentrations of NaCl, lacked an isokinetic temperature. Nevertheless the ΔH #/ΔS # plot was apparently linear with a slope corresponding to 314° K. It was concluded that linear thermodynamic compensation of thermal death is non-existent in heterogeneous groups of yeasts and is unlikely to occur in heterogeneous groups of other organisms and that ΔH #/ΔS # plots lack sensitivity for the detection of non-linearity over narrow temperature ranges. However, the ΔH # and ΔS # parameters of thermal death displayed non-linear compensation in such a way that the extrapolated Arrhenius plots of death attained nearly identical values near the respective maximum temperatures for growth. Linear thermodynamic compensation occurred in each of the six strains, when stationary populations of the same strain were tested at various NaCl concentrations. On the other hand, exponential populations of each of the strains, tested in the same way, lacked an isokinetic temperature of thermal death. The significance of linear and non-linear thermodynamic compensation in biological rate processes is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00454855
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 32
    Electronic Resource
    Electronic Resource
    Mating reaction in yeast protoplasts (1976)
    Springer
    Archives of microbiology 110 (1976), S. 313-318 
    Details
    ISSN: 1432-072X
    Keywords: Yeast protoplasts ; Saccharomyces cerevisiae ; Conjugation ; Cell wall ; Morphogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Protoplasts prepared from complementary haploid strains ofSaccharomyces cerevisiae were studied with regard to their ability of conjugating. Neither fresh protoplasts nor the growing protoplasts possessing fibrillar walls exhibited sex specific agglutination or fusion. However, they were capable of inducing sexual activation in normal cells of opposite mating type. After completing the regeneration of cell walls the protoplasts could conjugate either with each other or with cells of opposite sex. The frequency of conjugations was low, about 1%, and was largely dependent on the degree of completition of the wall during regeneration. From the results the following conclusions may be drawn: 1. The initiation of mating is dependent on the integrity of the cell wall. 2. The sex specific morphogenetic changes do not occur in wall-less protoplasts but may happen after the protoplasts have regenerated their cell walls. 3. The lysis of cell walls does not occur until the walls come into close contact. 4. The fusion of plasma membranes in sex-activated protoplasts cannot be induced by artefucial agglutination.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00690244
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    Isothermic variation of the specific growth rate of Saccharomyces cerevisiae in batch culture (1977)
    Springer
    Archives of microbiology 113 (1977), S. 303-307 
    Details
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Specific growth rate ; Growth control ; Glucose transfer ; Glucose-6-phosphate ; Maintenance requirements
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The specific growth rate (μ) of a respiration-deficient mutant of Saccharomyces cerevisiae growing under defined experimental conditions in batch culture (mineral medium plus glucose and vitamins at 25°C) varied from experiment to experiment over a wide range (0.10–0.24 h-1) and showed a normal distribution. Neither the age of the culture, the history of the inoculum, nor experimental error accounted wholy for the variability of μ. The variation was positively correlated with the specific rate of glucose transfer and negatively with the specific rate of production of non-fermentative CO2. The yield decreased with μ implying higher maintenance requirements in batch culture (4.7 mmoles g-1 h-1) than in continuous culture (0.8 mmoles g-1 h-1). It was concluded that the strain is capable of establishing any one of several steady states of growth under the same experimental conditions, each steady state displaying some buildin inertia with respect to change. The variations of the specific rates of glucose transfer and non-fermentative CO2 production, and of the yield appeared to be consequences rather than causes of the variation of μ. The ultimate causes of the variation of μ remained unidentified.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00492039
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    Mode of increase in cell wall polysaccharides in synchronously growing Saccharomyces cerevisiae (1977)
    Springer
    Archives of microbiology 114 (1977), S. 91-92 
    Details
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Cell wall ; Glucan ; Mannan ; Synchronous culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The mode of increase in cell wall polysaccharides of yeast (glucan and mannan) during cell cycle was analyzed using cell wall samples obtained from a synchronous culture. The increase in mannan and total glucan proceeded almost linearly throughout the cell cycle except for a short period of their leveling off at the time of cell division. However, the constituents of glucan behaved characteristically: Alkalisoluble glucan and insoluble glucan increased mainly in the former and the latter half of the cell cycle, respectively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00429637
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    Action of tryptophan analogues in Saccharomyces cerevisiae (1977)
    Springer
    Archives of microbiology 115 (1977), S. 307-316 
    Details
    ISSN: 1432-072X
    Keywords: Anthranilate synthase, feedback inhibition of ; Saccharomyces cerevisiae ; Tryptophan analogues, mode of action of ; Tryptophan biosynthetic enzymes ; Tryptophan pool
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In an analysis of the effects of various tryptophan and indole analogues in Saccharomyces cerevisiae we determined the mechanisms by which they cause growth inhibition: 4-Methyltryptophan causes a reduction in protein synthesis and a derepression of the tryptophan enzymes despite of the presence of high internal levels of tryptophan. This inhibition can only be observed in a mutant with increased permeability to the analogue. These results are consistent with but do not prove an interference of this analogue with the charging of tryptophan onto tRNA. 5-Methyltryptophan causes false feedback inhibition of anthranilate synthase, the first enzyme of the tryptophan pathway. This inhibits the further synthesis of tryptophan and results in results in tryptophan limitation, growth inhibition and derepression of the enzymes. Derepression eventually allows wild type cells to partially overcome the inhibitory effect of the analogue. 5-Fluoroindole is converted endogenously to 5-fluorotryptophan by tryptophan synthase. Both endogenous and externally supplied 5-fluorotryptophan are incorporated into protein. This leads to intoxication of the cells due to the accumulation of faulty proteins. 5-Fluorotryptophan also causes feedback inhibition of anthranilate synthase and reduces the synthesis of tryptophan which would otherwise compete with the analogues in the charging reaction. Indole acrylic acid inhibits the conversion of indole to tryptophan by tryptophan synthase. This results in a depletion of the tryptophan pool which, in turn, causes growth inhibition and derepression of the tryptophan enzymes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446457
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    Electron microscopy of germinating ascospores ofSaccharomyces cerevisiae (1978)
    Springer
    Archives of microbiology 117 (1978), S. 73-77 
    Details
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Ascospores ; Germination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The wall of mature ascospores ofSaccharomyces cerevisiae showed in sections under the electron microscope a dark outer layer and a lighter inner layer. The latter was composed of a greyish inner part and a light outer part. During germination, the spore grew out at one side and the dark outer layer was broken. Of the light inner layer, the inner greyish part became the wall of the vegetative cell, but the extented part of the cell had a new wall.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00689354
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    Metabolism of the anaerobic formation of succinic acid bySaccharomyces cerevisiae (1978)
    Springer
    Archives of microbiology 117 (1978), S. 269-276 
    Details
    ISSN: 1432-072X
    Keywords: Succinic acid ; Fermentation ; Saccharomyces cerevisiae ; α-ketoglutarate dehydrogenase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 1. Succinic acid is formed in amounts of 0.2–1.7 g/l by fermenting yeasts of the genusSaccharomyces during the exponential growth phase. No differences were observed between the various species, respiratory deficient mutants and wild type strains. 2. At low glucose concentrations the formation of succinic acid depended on the amount of sugar fermented. However, the nitrogen source was found to be of greater importance than the carbon source. 3. Of all nitrogen sources, glutamate yielded the highest amounts of succinic acid. Glutamate led to an oxidative and aspartate to a reductive formation of succinic acid. 4. A reductive formation of succinic acid by the citric acid cycle enzymes was observed with malate. This was partially inhibited by malonate. No evidence was obtained that the glyoxylate cycle is involved in succinic acid formation by yeasts. 5. Anaerobically grown cells ofSaccharomyces cerevisiae contained α-ketoglutarate dehydrogenase. Its activity was found in the 175000 x g sediment after fractionated centrifugation. The specific activity increased 6-fold after growth on glutamate as compared with cells grown on ammonium sulfate. 6. The specific activities of malate dehydrogenase, fumarase, succinate dehydrogenase, succinylcoenzymeA synthetase, α-ketoglutarate dehydrogenase and glutamate dehydrogenase (nicotinamide adenine dinucleotide dependent) were determined in yeast cells grown on glutamate or ammonium sulfate. Similar results were obtained with a wild type strain and a respiratory deficient mutant. The latter did not contain succinate dehydrogenase. 7. In fermenting yeasts succinic acid is mainly formed from glutamate by oxidation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00738546
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    Changes in the rate of synthesis of wall polysaccharides during the cell cycle of yeast (1978)
    Springer
    Archives of microbiology 119 (1978), S. 213-214 
    Details
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Cell wall ; Glucan ; Mannan ; Cell cycle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Reevaluation and comparison of seemingly contradictory literature data on the mode of synthesis of wall polysaccharides during the cell cycle ofSaccharomyces cerevisiae explained the source of discrepancies and demonstrated their general consonance in the following points: 1. The rate of synthesis of glucan and mannan is not constant and does not increase continuously throughout the entire cell cycle. 2. The rate of synthesis of both polysaccharides is considerably reduced at the time of cell division and in the prebudding phase.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00964275
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    Location of mannan and chitin on thin sections of budding yeasts with gold markers (1977)
    Springer
    Archives of microbiology 115 (1977), S. 1-7 
    Details
    ISSN: 1432-072X
    Keywords: Cell walls ; Chitin ; Colloidal gold ; Concanavalin A ; Cytochemistry ; Mannan ; Wheat germ agglutinin ; Yeast ; Saccharomyces cerevisiae ; Candida utilis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Mannan was located on thin sections of Saccharomyces cerevisiae and Candida utilis with the homologous anti-mannan antibodies or with Concanavalin A, both labelled with gold granules. Fully synthesized mannan was found in the cell walls, on the plasmalemma and within the cytoplasm sometimes associated with vesicles and vacuoles. Chitin or its oligomers were located with wheat germ agglutinin in the bud scars but also in the cell wall and the cytoplasm near the plasmalemma. Both mannan and chitin or its oligomers were found in the forming septum and are synthesized within the cytoplasm. The gold method was also suitable for marking mannan and chitin simultaneously.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00427837
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    Rapid decrease of ATP content in intact cells of Saccharomyces cerevisiae after incubation with low concentrations of sulfite (1979)
    Springer
    Archives of microbiology 121 (1979), S. 225-229 
    Details
    ISSN: 1432-072X
    Keywords: Sulfur dioxide ; Sulfite ; Air polluting substances ; Saccharomyces cerevisiae ; ATP hydrolysis ; Reversibility of sulfite effect
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Sulfite, at concentrations above 1 mM and at a pH below 4, caused cell death in Saccharomyces cerevisiae X2180 as measured by the colony-forming capacity. A rapid decrease in the ATP content was observed prior to cellular death. The depletion of ATP was reversible and the lethal effect could be prevented if the cells were exposed to sulfite for periods of less than 1 h. Extent and rate of ATP depletion were dependent on time, pH value, temperature and sulfite concentrations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425059
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    Influence of defined gene blocks on the competitive ability of yeast genotypes (1977)
    Springer
    Biochemical genetics 15 (1977), S. 1015-1021 
    Details
    ISSN: 1573-4927
    Keywords: Saccharomyces cerevisiae ; enzymes ; polymorphisms ; competition ; variable environments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Competition experiments were carried out under varying exogenic and endogenic conditions. The genotypes were marked by combinations of two esterase loci, each with two alleles. When genotypes of the line W7 were used, there was no demonstrable influence of the gene blocks marked by the Est-1 locus on the competitive ability at temperatures of 21 and 29 C. However, genotypes carrying the fast allele of the Est-2 locus were favored. At 38 C, the outcome of the competition was reversed. The defined gene blocks showed different effects when interacting with different genetic backgrounds (line M7). Genotypes marked by the slow allele of the Est-2 locus were now favored (21 and 29 C), and even the gene blocks marked by the alleles of the Est-1 locus influenced the genotypes' competitive abilities. Again, the results were partly reversed at 38 C. The results are discussed with regard to the importance of enzyme variants for the genotypic selection value.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00484493
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    The surface of the pecten oculi in the pigeon (1975)
    Springer
    Cell & tissue research 157 (1975), S. 457-465 
    Details
    ISSN: 1432-0878
    Keywords: Pecten oculi ; Pigeon ; Surface ; Function ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A scanning electron microscopic study of the pecten reveals the rib-like character of the pectinal folds, the nature of their connections with the base and bridge of the pecten as well as the presence of interconnections between the bundles of superficial collagenous fibres. It has been suggested that the pecten may have a mechanical significance, namely protection of the retina from the excessive movements of the vitreous humour. The relationship between the superficial membrane of the folds which is continuous, the intercellular spaces and the process of diffussion has also been discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222599
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Scanning electron microscopic studies on the development of the chick retina (1976)
    Springer
    Cell & tissue research 170 (1976), S. 145-159 
    Details
    ISSN: 1432-0878
    Keywords: Neurogenesis ; Retina ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Fixed retinae of chick embryos and chicks of the first week after hatching were fractured and examined with the scanning electron microscope. The matrix cells of the retina proliferate up to the beginning of the second week. The migrating cells are oriented in cell cords. This columnar organization prevails up to the development of the plexiform layers formed as a consequence of the outgrowth of the dendritic and axonal cell processes. Special attention was paid to the differentiation of the ganglion, bipolar and receptor cells, and the radial fibers (Müller cells). Two main morphological patterns are significant for the organization of the retina during neurogenesis: a) the cell to cell contacts of migrating cells and b) the spatial arrangement of Müller cells which could provide guidelines for migration of neuronal elements.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00224296
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    Osteoblasts and collagen orientation (1975)
    Springer
    Cell & tissue research 159 (1975), S. 73-80 
    Details
    ISSN: 1432-0878
    Keywords: Osteoblasts ; Collagen orientation ; Parietal bone ; Rat, Rhesus monkey ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Bone was removed from the calvaria of anaesthetized 70 g rats or freshly killed young monkeys and the fibrous periosteum dissected off the inner, formative surface under 0.15 M cacodylate buffer. The bone and undisturbed osteoblasts were fixed in 3% glutaraldehyde in the same buffer for 24 to 48 hours, critical point dried and coated with evaporated carbon and gold for scanning electron microscopy (SEM). Fields of osteoblasts were photographed and chosen cells dissected off the osteoid using a tungsten needle. The control of the dissection was made possible by the use of a system of real-time stereo TV-speed SEM. The fields were rephotographed and the orientations of the osteoblasts were compared with that of the underlying collagen fibres. 62% of all osteoblasts lay with their long axes within 15° of the collagen fibre orientation below and 80% within 30°. Montages of large areas of osteoblasts were also made, and then compared with ones of the same area after the cells had been stripped off on adhesive tape. In general, the orientation of the collagen tended to be the same as the cell that formed it. Collagen fibres below cells at the periphery of a domain sometimes had the orientation of the cells in the adjacent patch. It is not possible to determine whether the cells controlled the orientation of the collagen, or vice versa, from this experiment, but other SEM evidence suggests that the collagen orientation in hard tissue matrices depends on the freedom of cells to move with respect to the matrix surface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00231996
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    Scanning electron microscopic studies of the rat incisor odontoblastema (1975)
    Springer
    Cell & tissue research 159 (1975), S. 233-243 
    Details
    ISSN: 1432-0878
    Keywords: Odontoblasts ; Predentine ; Dentine ; Calcification ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A scanning electron microscopic technique was used to investigate the surface structure of dentinogenically active odontoblasts. Thin pieces of rat incisors were fixed, rapidly frozen, freezedried at -70° C and fractured to expose new surfaces prior to examination in the SEM. Differences in the appearance of odontoblastic cell surfaces were seen, with the most extensive ridge formations at the distal part of the sides of the odontoblasts. The predentine area displayed a spongy structure which contrasted to the compact appearance of dentine. Results are discussed in relation to previous studies at the light microscopic and transmission electron microscopic levels.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219159
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Electron microscopic studies of the lung of the frog (1975)
    Springer
    Cell & tissue research 160 (1975), S. 399-410 
    Details
    ISSN: 1432-0878
    Keywords: Lung ; Frog ; Alveolar epithelium ; Mucus layer ; Scanning electron microscopy ; Transmission electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Scanning and transmission electron microscopy were used to study the inner architecture of the frog lung. In some specimens the alveolar surface mucus layer was removed to permit the examination of underlying features. The inner surface of the frog's lung is covered by a layer of microvilli belonging to only one type of epithelial cells. The boundaries of these epithelial cells are demarcated by small ridges. Different degrees of lung expansion cause variations of the surface topography. The morphology of certain surface features is examined in detail. Several methods of drying the specimens are compared.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222048
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    Comparative scanning electron microscope study of boar, bull and ram spermatozoa (1975)
    Springer
    Cell & tissue research 161 (1975), S. 329-341 
    Details
    ISSN: 1432-0878
    Keywords: Spermatozoa ; Boar, bull, ram ; Surface ultrastructure ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé La morphologie comparée des spermatozoïdes éjaculés de Verrat, Taureau et Bélier a été étudiée au microscope à balayage. Le sperme lavé est fixé dans le glutaraldéhyde ou le mélange acide picrique-formaldéhyde-glutaraldéhyde. Les échantillons sont le plus souvent désséchés par la méthode du point critique (Fréon) sur un filtre et aussi dans l'air sur une lamelle de verre. La tête des spermatozoïdes de ces trois espèces présente la même forme en pagaie aplatie formée de trois régions principales: les deux segments, antérieur, entouré d'un épaississement marginal, et équatorial de l'acrosome et la région postacrosomique. La plupart des differentiations de la lame postacrosomique décrites en microscopie électronique à transmission sont visibles à travers la membrane plasmique, particulièrement après dessication à l'air. La morphologie superficielle du cou et des différentes parties du flagelle est aussi observable. Des différences spécifiques sont mises en évidence: chez le verrat seulement, par exemple, la surface de l'acrosome apparaît granuleuse, et aucune bordure antérieure dentelée de la lame postacrosomique n'est visible. La microscopie à balayage permet d'observer les grands traits et de fins détails de la morphologie superficielle d'un échantillon de sperme et aussi d'étudier les effects de traitements sur des spermatozoïdes (congélation, extraction de l'acrosome).
    Notes: Summary The comparative ultrastructure of ejaculated boar, bull and ram spermatozoa is studied by scanning electron microscopy. After washing, the spermatozoa are fixed in glutaraldehyde or in picric acid-formaldehyde-glutaraldehyde mixture. Samples are prepared either by critical point drying (Freon) on Millipore filters or by air drying on glass cover slips. In all the species studied, three regions may be distinguished in the paddle-shaped head of the sperm: an anterior segment (surrounded by the marginal thickening) and an equatorial segment constituting together the acrosome, and the postacrosomal region. Most of the feature of the postacrosomal lamina described in transmission electron microscopy are visible through the plasma membrane, particularly after air drying. The surface morphology of the neck and of the different segments of the flagellum is also evident. Some species differences are encountered, e.g. rough surface of acrosome and absence of serrations in postacrosomal lamina of boar spermatozoa only. The techniques employed result in good general morphology and fine resolution of surface detail of the sperm samples; they also permit analysis of spermatozoa treated by freezing or submitted to acrosomal extraction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220002
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    A combined scanning and transmission electron microscopic study and electron probe microanalysis of human pineal acervuli (1976)
    Springer
    Cell & tissue research 174 (1976), S. 129-137 
    Details
    ISSN: 1432-0878
    Keywords: Pineal organ, human ; Acervuli ; Scanning electron microscopy ; Transmission electron microscopy ; Electron probe microanalysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Untreated, decalcified and trypsinized acervuli from human pineal bodies were studied with the scanning and transmission electron microscope as well as by electron probe microanalysis. The mulberry-like acervuli are composed of a various number of spherical lobes (135–800 μm) between which clustered groups of globuli (4–14 urn in diameter) are observed. The acervular lobes are very probably formed by an aggregation of these globuli. Small round particles 125–500 Å in diameter are observed on the surface of the pineal concretions. These are not influenced by either decalcification or trypsin treatment. The acervular mineral corresponds morphologically to hydroxyapatite. The electron probe microanalysis reveals the existence of calcium and phosphorus as main components of the acervuli. Small quantities of magnesium and strontium were also detected.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222155
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    Scanning electron microscopy of dissociated pancreatic acinar cell surfaces (1977)
    Springer
    Cell & tissue research 176 (1977), S. 493-504 
    Details
    ISSN: 1432-0878
    Keywords: Pancreas ; Acinar cells ; Cell surface ; Dissociation ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pancreatic acinar cell surfaces have been studied by SEM with a dissection technique and correlated with results obtained by TEM. The SEM results demonstrate characteristic arrangement of microplicae which in some areas are densely packed. In many areas, the microplicae are distributed in such a manner that they create zones with typical geometrical shapes and show a relatively smooth surface. These smooth areas may coincide, as indicated by correlated TEM results, with the limits of intimate contact between adjacent acinar cells which, in turn, represent part of the junctional complex. Another aspect revealed by these SEM preparations concerns the presence of groups of densely packed microplicae, arranged in regular rows and distributed along some grooves and/or infoldings of the cellular surface. On the basis of SEM and TEM information, it is likely that these structures correspond to intercellular (and possibly, in some cases, intracellular) canaliculi which topographically form a kind of extensive microlabyrinthine arrangement running along all the cell sides. One final point revealed by fractured samples concerns the finding of spherical zymogen droplets within the vesicles of the Golgi complex. Because in many scanning images these vesicles appear connected by small openings, it is suggested that they may represent a system of intercommunicating chambers (vacuoles) through which the zymogen droplets can be continuously accumulated and discharged into the acinar lumen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00231404
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    The third ventricle of monkeys (1977)
    Springer
    Cell & tissue research 177 (1977), S. 307-316 
    Details
    ISSN: 1432-0878
    Keywords: Third ventricle ; Mature monkeys ; Scanning electron microscopy ; Ependyma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Surface features of the ependymal lining of the third ventricle in mature male and female monkeys have been investigated with scanning electron microscopy (SEM). Broad aspects of third ventricular morphology from three species of monkey are similar regardless of sex. The lateral walls are heavily ciliated whereas the ventral floor and most ventral parts of the lateral walls are not. Clumps of cilia on the lateral walls are so dense that underlying surface details are usually obscured. There is a transition zone between the ciliated lateral wall and nonciliated ventral floor. The floor and lower part of the lateral walls of the third ventricle exhibit a characteristic polygonal pattern upon which surface specializations such as microvilli, blebs and polymorphous membrane protrusions are superimposed. Ependyma of the choroid plexus of the third ventricle also display membrane specializations. Supraependymal cells are more visible in nonciliated regions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220306
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    The surface fine structure of the bovine subcommissural organ (1975)
    Springer
    Cell & tissue research 163 (1975), S. 125-132 
    Details
    ISSN: 1432-0878
    Keywords: Bovine subcommissural organ ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The bovine subcommissural organ was studied by using scanning electron microscopy. The most prominent finding was the existence of protruded and dilated endings of the ependymal cells. The majority of these cells were ciliated with two or more cilia; only a few unciliated cells were seen. Some pore-like structures were also seen on the surface. From the functional point of view, the most interesting finding was an amorphous heterogeneous material on the subcommissural ependyma. Especially in the caudal part of the organ this material accumulated in abundance. No real filamentous structures such as Reissner's fibre could be seen, however, it was assumed that the heterogeneous material corresponds to this formation. No supraependymal neurones were demonstrated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221721
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 52
    Electronic Resource
    Electronic Resource
    Neuronal migration during the early development of the cerebral cortex (1975)
    Springer
    Cell & tissue research 163 (1975), S. 313-325 
    Details
    ISSN: 1432-0878
    Keywords: Neurogenesis ; Cerebral cortex ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Fixed cerebral vesicles of mouse foetuses were fractured and examined with the scanning electron microscope. This method provides a study of the three dimensional developmental features of the pseudostratified columnar epithelium up to the formation of the early cortex plate. Matrix cells are a cell population of homogeneous shape, however, mitotic cells are easily identified by their spherical form. The external surface of the brain is formed by the closely packed end feet of these cells covered by a basal membrane. The formation of the cortical plate is the result of a continuous cell migration in columnar arrangement towards the pia. Glioependymal cells extend along the whole brain wall and most likely provide guidance for the migrating cell cords. The formation of the so-called migratory zone is a consequence of the growth of the basal and the horizontal prolongations of emigrating cells. The significance of the cell to cell contacts for the neuronal migration processes is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219466
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 53
    Electronic Resource
    Electronic Resource
    Morphology, morphometry and electron microscopy of HeLa cells infected with bovine Mycoplasma (1976)
    Springer
    Cell & tissue research 170 (1976), S. 1-16 
    Details
    ISSN: 1432-0878
    Keywords: Tissue culture cells ; Mycoplasma ; Light microscopy ; Transmission electron microscopy ; Scanning electron microscopy ; Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The host-parasite relationship of HeLa M cells artificially infected with a bovine species of Mycoplasma was studied by light microscopy, transmission electron microscopy and scanning electron microscopy. The use of morphometry to quantitate some of the findings was explored. The parasites were seen in locations extracellular to the cell surface. The detection of small numbers of organisms by light microscopy was well demonstrated by use of the fluorescent antibody technique. Scanning electron microscopy proved to be an excellent method for revealing the surface details of cell-parasite morphology. Ultra-thin sections showed that the parasites are aligned mostly parallel to the plasma membrane of the host cell but separated by a gap of 10 nm. Morphometry indicated an average of 69 organisms per cell surface occupying 1.7% of the surface area. An increase of 26% in diameter of the HeLa cells, possibly as a result of infection, was observed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220107
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 54
    Electronic Resource
    Electronic Resource
    A scanning electron microscope study of the development of free axonal sprouts at the cut ends of dorsal spinal nerve roots in the rat (1976)
    Springer
    Cell & tissue research 170 (1976), S. 507-513 
    Details
    ISSN: 1432-0878
    Keywords: Axons ; Scanning electron microscopy ; Neurones, afferent ; Nerve regeneration ; Spinal nerve roots
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Rat dorsal spinal nerve roots were cut and the tip on the ganglionic side of the cut was examined by scanning electron microscopy at 0, 7, 20 and 48 h after operation. Seven hours after cutting, free axonal sprouts had started to protrude from the cut end of the nerve. After 20 h the free sprouts were more profuse than at 7 h but were smaller and had a rougher surface. At both 7 and 20 h many of the sprouts consisted of a stalk 2–7 μm in diameter with a bulbous end 5–20 μm in diameter. A few branching sprouts were seen. At 48 h the sprouts were shrunken with a deeply furrowed surface. The significance of the surface structure of the sprouts is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00361708
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 55
    Electronic Resource
    Electronic Resource
    Effects of castration and androgen-substitution on the morphology of the epididymal epithelium of the Japanese monkey, Macacus fuscatus, as revealed by scanning electron microscopy (1976)
    Springer
    Cell & tissue research 170 (1976), S. 515-521 
    Details
    ISSN: 1432-0878
    Keywords: Epididymal epithelium ; Castration ; Androgen-substitution ; Japanese monkey ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The caput epididymidis from castrated and androgen-supplemented, castrated Japanese monkeys was observed with the scanning electron microscope. The experimental findings were compared with the normal structures in control animals. The epididymal lumen of control animals was lined by a tall, pseudostratified columnar epithelium possessing long, slender stereocilia which were densely arranged in a tuft-like form. After castration, the epididymal epithelium was decreased in height to one-fifth of controls. The stereocilia were also considerably reduced in length and in number, resulting in a flattened epithelial surface with polygonal boundaries. Frequent projection of a long, single cilium from an epithelial cell into the lumen was also a prominent feature in the epididymal ducts of the castrated animals. Administration of testosterone to the castrated animals resulted in almost complete recovery of the epididymal epithelium as well as regeneration of the stereocilia which regained a tuft-like arrangement.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00361709
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 56
    Electronic Resource
    Electronic Resource
    The distal ommatidium of the compound eye of the housefly (Musca domestica): A scanning electron microscope study (1975)
    Springer
    Cell & tissue research 159 (1975), S. 379-385 
    Details
    ISSN: 1432-0878
    Keywords: Compound eye ; Musca domestica ; Ommatidium ; Distal retinula ; Scanning electron microscopy ; Corneal lens ; Corneal pigment cell ; Pseudocone ; Semper cell ; Basement membrane
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distal aspect of the housefly ommatidium was surveyed by the scanning electron microscope. Attention was directed to the somal eminence of the superior central cell and the lens to large pigment cell junction. The underside of each lens facet exhibits six hexagonally arranged incisures. Into each of these indentations are fitted several large pigment cells. This hexagonal indentation appears to be a tenacious anchorage. Two corneal pigment cells laterally encircle the pseudocone and at their proximal extension they enclose the Semper cells and neck of the retinula. The somal eminence of the superior central cell is about 10 μm from the base of the corneal pigment cell enclosure. Micrographs were used to construct a diagram of the ommatidium above the basement membrane. Suggestions are made as to the functional correlates of the observed ommatidial structures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221784
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 57
    Electronic Resource
    Electronic Resource
    The aesthetes of chitons (1976)
    Springer
    Cell & tissue research 172 (1976), S. 379-388 
    Details
    ISSN: 1432-0878
    Keywords: Chitons ; Receptors ; Shell surface ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The shells of the chitons Lepidochitona cinereus, Sypharochiton pelliserpentis, Amaurochiton glaucus and Onithochiton neglectus were examined by scanning electron microscopy. In all species the surface terminations of the megalaesthete and micraesthete organs could be identified lying flush with the shell surface, as well as, lenses of the shell eyes in O. neglectus. Periostracal debris and encrusting diatoms were a usual feature of the shell surfaces. The micraesthete subsidiary caps normally appear featureless, but the megalaesthete apical caps sometimes appear to be perforated. The reasons for this perforate appearance are discussed and it is concluded that it provides no evidence for the normal passage of substances out of or into the megalaesthete.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00399520
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 58
    Electronic Resource
    Electronic Resource
    Light- and scanning electron microscopical studies of the hypothalamo-adenohypophysial portal vessels of the toad Bufo bufo (L.) (1975)
    Springer
    Cell & tissue research 162 (1975), S. 131-139 
    Details
    ISSN: 1432-0878
    Keywords: Hypothalamo-adenohypophysial region Bufo bufo (L.) ; Portal vessels ; Methyl-methacrylate casts ; Light microscopy ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The vascularization of the hypothalamo-adenohypophysial region of the toad Bufo bufo (L.) (Amphibia, Anura) was studied by means of light- and scanning electron microscopy. Special attention was given to the portal vascular system of the median eminence and the pars distalis. Course and arrangement of these vessels are described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00223268
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 59
    Electronic Resource
    Electronic Resource
    Surface fine structure of the globiferous pedicellariae of the regular echinoid, Psammechinus miliaris gmelin (1975)
    Springer
    Cell & tissue research 162 (1975), S. 377-385 
    Details
    ISSN: 1432-0878
    Keywords: Globiferous pedicellariae ; Psammechinus miliaris ; Microvilli ; Chemoreceptor ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The globiferous pedicellariae of Psammechinus miliaris are described. Two fixation methods giving minimal distortion and rapid tissue hardening were adapted for soft tissue preparation for scanning electron microscopy. The pedicellarial valves are covered by a microvillous epithelium. The outer valve epithelial microvilli overlying red spherulocytes in the epidermis are characterized by a filament matrix radiating out from each microvillus. These microvilli may function in epidermal absorption of organic solutes. The inner valve microvilli are more densely packed and the filament matrix is absent. Ciliation is confined to the inner valve surface where the cilia are concentrated to form a distal sensory pad and sensory hillock. Behavioural evidence suggests a chemo- and mechanosensory role for the inner valve surface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220184
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 60
    Electronic Resource
    Electronic Resource
    A scanning electron microscopic study of the rat liver sinusoid (1975)
    Springer
    Cell & tissue research 164 (1975), S. 371-385 
    Details
    ISSN: 1432-0878
    Keywords: Kupffer cell ; Endothelial cell ; Sinusoid ; Liver ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The surface ultrastructure of Kupffer cells in the rat liver has been studied by scanning electron microscopy (SEM). The results demonstrate that Kupffer cells are both significantly different and clearly distinct from endothelial cells. Kupffer cells have neither pores (and/or “sieve plates”) nor fenestrations, all of which are present in endothelial cells. They possess a stellate shape, and only indirectly, with slender and irregular evaginations, contribute to the lining of the sinusoidal wall. Furthermore, the luminal surface in some areas contains a large population of short microvilli, microplicae and invaginations. These elements form a kind of microlabyrinth which may correspond to the “worm-like” structures described by transmission electron microscopy (TEM). In the present study, transition forms between endothelial and Kupffer cells were never found. On the contrary, considering the highly fenestrated nature of the endothelial cells, the Kupffer cells may, by ameboid movements, easily cross the overlapping barrier of the sinusoid and protrude into the lumen. Thus, acting as activated macrophages, the Kupffer cells might function to prevent the entrance of foreign material into the tissues of the liver through the fragile and highly fenestrated endothelium. Finally, the topographical reconstruction of the sinusoid by correlated SEM and TEM studies demonstrates that Kupffer cells, with their protruding cytoplasm and ability to extend into the lumen of the sinusoid, may actually change the caliber of the vessel, and thus function as a “sphincter” which causes a temporary arrest of the blood flow when the diameter of the sinusoidal lumen is reduced.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00223015
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 61
    Electronic Resource
    Electronic Resource
    Scanning electron microscope observations on the muscle innervation of Oikopleura dioica fol (appendicularia, tunicata) with notes on the arrangement of connective tissue fibres (1975)
    Springer
    Cell & tissue research 164 (1975), S. 357-369 
    Details
    ISSN: 1432-0878
    Keywords: Neuromuscular junctions ; Appendicularia (Oikopleura dioica) ; Connective tissue fibrils ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Critical point dried and fractured appendicularia of the species Oikopleura dioica have been examined in the scanning electron microscope. The dorsal nerve cord with ganglion cells and peripheral nerve fibres could easily be observed. Thick peripheral nerve fibres leave the nerve cord as bilateral pairs at constant intervals along the tail. Most of these fibres branch from the naked nerve cord, but some evidently originate in ganglion perikarya bulging out from the nerve cord itself. These paired peripheral nerves always have elaborate end-arborizations on the medial surface of the lateral muscle cells. They are accordingly interpreted as motor axons. Some thinner peripheral nerve fibres originate at irregular intervals from both the nerve cord and the ganglion cells. Due to the numerous extracellular fibrils that connect the bilateral layers of the epidermal fins and the muscle cells to each other, these thin nerve fibres can seldom be traced to their termination. A few ones can, however, be traced ventrally between the notochord and the muscle cells and seem to end in singular bulb-like expansions. Clusters of synaptic vesicles are present in transmission electron micrographs of such nerves, and they are accordingly believed to carry efferent impulses. The extracellular fibrils are arranged in a highly ordered pattern with thick bundles crossing the gap between the structures to be interconnected and with numerous radiating insertions on the surface of the tissues.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00223014
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 62
    Electronic Resource
    Electronic Resource
    Scanning electron microscopy of bone cells in culture (1976)
    Springer
    Cell & tissue research 166 (1976), S. 65-70 
    Details
    ISSN: 1432-0878
    Keywords: Collagen ; Bone ; Cell culture ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Embryonic and young rat bone cells have been grown in culture and examined in the scanning electron microscope (SEM). Compared with cells fixed in situ and taken directly from the animal, the cultured osteoblastic cells were smoother, flatter and more extensive and showed tighter intercellular contacts. Some matrix is formed in culture and undergoes at least partial mineralization as judged by the accumulation of Ca and P measured by energy dispersive x-ray analysis. Findings concerning the morphology of the collagen arrangement were indecisive. Some superficial cells, free of surrounding matrix, resembled osteocytes in normal in vivo bone. This may indicate that a proportion of the extracellular matrix produced by the cultured cells failed to polymerise into recognizable bone matrix, and that osteocytic morphology is not dependent upon the physical characteristics of the bone matrix.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215125
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 63
    Electronic Resource
    Electronic Resource
    Interaction of rabbit sperm and egg (1976)
    Springer
    Cell & tissue research 169 (1976), S. 277-287 
    Details
    ISSN: 1432-0878
    Keywords: Rabbit gametes ; Cryofractography ; Scanning electron microscopy ; Transmission electron microscopy ; Zona pellucida
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Rabbit ova fertilized in vitro were prepared for scanning electron microscopy by ethanol-cryofracturing and critical-point drying methods and were also embedded and sectioned for transmission electron microscopy. Study of a region of interaction between sperm and zona pellucida with scanning electron microscopy reveals the latter to be composed of a complex network of fibers interspersed with numerous pores. Transmission electron microscopy of the same region reveals a “typical” homogeneous composition of the zona pellucida. Ultrastructural observations of thin sections passing through the region of sperm-egg interactions or through other regions of the ovum or its investments reveals very little methodological distortion of the various intracellular organelles or matrix. Application of the procedures described provides not only an elucidation of surface detail but also reveals intracellular cytoplasmic information about the same specimen during in vitro fertilization.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219601
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 64
    Electronic Resource
    Electronic Resource
    Experimental study of changes in osteoblastic shape induced by calcitonin and parathyroid extract in an organ culture system (1976)
    Springer
    Cell & tissue research 169 (1976), S. 449-465 
    Details
    ISSN: 1432-0878
    Keywords: Bone ; Osteoblasts ; Cell surface ; Cell shape ; Calcitonin ; Parathyroid extract ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neonate rat endocranial osteoblasts were cultured on their bone surfaces in control medium (CC) or medium to which either parathyroid extract (PTE) or calcitonin (CT) had been added for 2, 4, 8 or 24 h. Some were cultured for 24 h in CC, then for 2, 4, 8 or 24 h in either CT or PTE medium; or for 24 h in PTE, then for 2, 4, 8 or 24 h in either CC or CT; or 24 h in CT and 2, 4, 8 or 24 h in CC. The dorsal ruffling of the cells in CC was found to be suppressed by later culturing with PTE and the disoriented cells reorganized to form arrays of parallel cells. The effects of PTE were also reversed by CC or CT: the osteoblasts in the second culture (CC) lost elongation and order, and proceeded through a proliferative phase before exhibiting the ruffling form similar to a single CC 24 h culture. PTE-cultured osteoblasts showed an increase in cell overlap and contact so that a more competent barrier was formed separating the bone from the medium. In control or CT medium, however, intercellular gaps were greater than in vivo.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218146
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 65
    Electronic Resource
    Electronic Resource
    The Surface structure of isolated pancreatic islet cells (1975)
    Springer
    Cell & tissue research 164 (1975), S. 467-471 
    Details
    ISSN: 1432-0878
    Keywords: Pancreas ; Islets ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The surfaces of isolated pancreatic islet cells were studied with the scanning and transmission electron microscopes. Islets were isolated from the pancreas of Wistar rats by collagenase treatment and were incubated either in glucose-free medium or in 300 mg% glucose for one hour. Immunoreactive insulin (IRI) in the media of both control and experimental preparations was assayed. Islets were then transferred to 4% glutaraldehyde, buffered with cacodylate, pH 7.4, and prepared for scanning and transmission electron microscopy. Cell masses average 200 μ in diameter. Alpha cells appear pyramidal in shape, are about 8 μ in diameter and appear in groups. Beta cells are round or oval in shape and have an average diameter of 10 μ. Glucose stimulation raised the IRI value tenfold and increased the number of blebs and other surface irregularities per unit area of beta cell surface. Comparison with transmission electron micrographs suggests that the blebs are related to the process of emiocytosis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219938
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 66
    Electronic Resource
    Electronic Resource
    A critical reevaluation of the structure of the rat uriniferous tubule as revealed by scanning electron microscopy (1976)
    Springer
    Cell & tissue research 166 (1976), S. 91-100 
    Details
    ISSN: 1432-0878
    Keywords: Kidney (rat) ; Uriniferous tubule ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of luminal surface of clearly identified portions of uriniferous tubules has been studied by scanning electron microscopy to elucidate some controversies concerning the topography of certain surface formations. The results show a characteristic pattern of the luminal surface in the region of Henle's loop, which was assumed by previous authors, to belong to the collecting tubule. Furthermore it is demonstrated that no cilia are present within the terminal portion of the collecting tubules.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215128
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 67
    Electronic Resource
    Electronic Resource
    Aggregation-induced alterations in fibroblast morphology (1976)
    Springer
    Cell & tissue research 174 (1976), S. 499-518 
    Details
    ISSN: 1432-0878
    Keywords: Fibroblast ; Human ; Transmission electron microscopy ; Scanning electron microscopy ; Aggregation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The different stages during aggregation of diploid human skin fibroblasts have been examined by transmission and scanning electron microscopy. As a result of aggregation, fibroblasts form a complex tissue configuration. Numerous intercellular junctions can be observed, while the cells remain polygonal and do not develop an organised intracellular cytoskeleton. Cell division occurs only rarely. After aggregation, signs of progressive auto-digestion develop. Adhesion to a substrate results in outgrowth of the cells and monolayer formation, even when extensive cell damage had occurred. The morphology of fibroblasts in aggregates and in the monolayers, from which they were derived, is compared and the contribution of the aggregate system to the study of fibroblast behavior is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00232835
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 68
    Electronic Resource
    Electronic Resource
    Scanning electron microscopy of the glomerular filtration membrane in the rat kidney (1976)
    Springer
    Cell & tissue research 166 (1976), S. 299-314 
    Details
    ISSN: 1432-0878
    Keywords: Renal glomerulus (Rat) ; Endothelial cells ; Blood capillaries ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The rat kidney was perfused with saline and glutaraldehyde, treated with Murakami's tannin-osmium impregnation method, ethanol-freeze cracked and dried by the critical point method. Gold-palladium evaporated specimens were observed in a field-emission scanning electron microscope. The glomerular filtration membrane, fractured in different planes was observed with the following results: 1. Adjacent pedicles originate from different podocytes. No interpedicular bridges of apparent cytoplasmic nature could be found. 2. The basement membrane, in grazing fractures shows a horizontally layered architecture. 3. The attenuated endothelial sheet (lamina fenestrata) is divided into compartments, which we suggest should be called “areolae fenestratae”, by cytoplasmic crests radiating from the nucleated portion of the endothelial cell. A crest also occurs along the cell margin, which contacts a similar crest at the margin of the adjacent cell. 4. The pores in the areolae fenestratae are variable in size (30−150 nm diameter). A knob-like projection from the apparently naked basement membrane is found in a portion of the pores. 5. Numerous microvilli may occur on the endothelium. Some of them anastomose and fuse with one another to form a net whose meshes appear identical with the endothelial pores. Domes and shelves formed of a fenestrated cytoplasmic sheet also occur above the ordinary level of the endothelial lining. A hypothesis implicating microvilli in partial renewal of the endothelial sheet is proposed. This study was assisted by Mr. K. Adachi of the SEM Laboratory at the Niigata University School of Medicine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220127
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 69
    Electronic Resource
    Electronic Resource
    Three-dimensional development of luminal projections and junctional complexes in the developing central nervous system blood vessels of the rat (1977)
    Springer
    Cell & tissue research 175 (1977), S. 541-549 
    Details
    ISSN: 1432-0878
    Keywords: Blood vessels ; High voltage electron microscopy ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The luminal surface features and Junctional complexes from developing blood vessels in the rat central nervous system have been studied by high-voltage electron microscopy and scanning electron microscopy. Developing blood vessels exhibit three types of luminal projections; marginal folds or ridges at Junctional complexes, ridges not at Junctional complexes and microvilli. Both types of ridges are associated with troughs or depressions in the luminal surface of the endothelial cell. Those ridges not associated with Junctional complexes take part in the production of enclosed tunnels in the endothelial cell cytoplasm. Fusion of the external leaflets of Junctional complexes between adjacent endothelial cells occurred, initially, near the luminal surface of the blood vessel with other small fusion sites forming in the direction of the basal lamina secondarily. Further fusion activity to produce the zonula occludens type junction appeared to spread outwards from the smaller fusion sites.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222417
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 70
    Electronic Resource
    Electronic Resource
    Classification of human placental villi (1979)
    Springer
    Cell & tissue research 200 (1979), S. 409-423 
    Details
    ISSN: 1432-0878
    Keywords: Human placenta ; Classification of villi ; Histology ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The classification of human placental villi was reviewed on the basis of material prepared by means of special methods. The material from in situ normal-term placentae was biopsied by aspiration into glutaraldehyde. The classification was made on the basis of light-microscopic observations of semithin sections, reconstructions from serial sections, and scanning-electron micrographs. The peripheral villous tree is roughly divided into stem (ramuli), intermediate and terminal villi. The intermediate villi may be further subdivided as mature and immature types, which are found between the stem and terminal villi. Some of the terminal villi possess a local specialization described as the neck region. The histological characteristics and the branching pattern of each type are described, and the basis of the proposed classification is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234852
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 71
    Electronic Resource
    Electronic Resource
    A scanning electron microscopic study of rabbit spermatozoa in the female reproductive tract following coitus (1975)
    Springer
    Cell & tissue research 163 (1975), S. 29-44 
    Details
    ISSN: 1432-0878
    Keywords: Spermatozoa ; Capacitation ; Uterus ; Acrosome Reaction ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The surface morphology of rabbit spermatozoa, fixed in situ (female reproductive tract) and prepared for scanning electron microscopy by critical point drying, was studied for as many as 36 hours post coitum. The findings demonstrate that 1) spermatozoa in the reproductive tract following coitus exist as a heterogenous, morphological population and 2) with time, shifts within this population from one predominant morphology to another take place. In the fresh ejaculate, most spermatozoa have intact surfaces free of membranous disruptions. With time, a process of labilization (denudation) of the membranes covering the acrosomal region occurs in a progressively larger proportion of spermatozoa. The labilization originates by a process of vesiculation and/or vacuolation and leads to the appearance of a series of small fenestrations or perforations of the surface membranes. The perforations coalesce, and gradually larger areas of the surface membranes are eroded such that by 15 hours post coitum, the outer acrosomal membrane, as well as other acrosomal areas, are to varying degrees, directly exposed to the uterine milieu. Secretory granules, picked up by cilia and transferred to the spermatozoa become localized over the acrosomal region shortly after coitus. The possible significance of these time-dependent, morphological events with the phenomena of capacitation and the “true” and “false” acrosome reactions are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218589
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 72
    Electronic Resource
    Electronic Resource
    The reality of arthropod cuticular laminae (1975)
    Springer
    Cell & tissue research 163 (1975), S. 411-413 
    Details
    ISSN: 1432-0878
    Keywords: Cuticle ; Laminae ; Arthropod ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Examination of etched pyramids of decapod crustacean cuticles with the scanning electron microscope indicates that laminae are continuous around the angles of the pyramids. This observation is in direct contrast to the result expected on Bouligand's (1965, 1971) hypothesis and suggests that laminae may be real structures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219475
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 73
    Electronic Resource
    Electronic Resource
    Photoreceptor-like outer segments in the pineal organ of the lovebird, Uroloncha domestica (Aves: Passeriformes) (1977)
    Springer
    Cell & tissue research 182 (1977), S. 139-143 
    Details
    ISSN: 1432-0878
    Keywords: Pineal organ ; Uroloncha domestica (Aves, Passeriformes) ; Photoreceptor-like cells ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the pineal organ of the lovebird, Uroloncha domestica, bulbous, cup-shaped and elongated outer segments of photoreceptor-like pinealocytes are demonstrated by scanning electron microscopy. These scarce outer segments, 4–11 μm in length, extend into the pineal lumen. The present structural observations speak in favor of photosensitive pinealocytes in the pineal organ of Uroloncha domestica. The relation of the photoreceptor-like pinealocytes to acetylcholinesterase-positive nerve cells and a nervous connection between the pineal and the brain indicate that the pineal organ of this passeriform species may be the site of neuroendocrine and photoreceptive functions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222062
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 74
    Electronic Resource
    Electronic Resource
    Surface morphology of lens fibers from eyes of normal and microphthalmic (Browman) rats (1976)
    Springer
    Cell & tissue research 167 (1976), S. 425-438 
    Details
    ISSN: 1432-0878
    Keywords: Scanning electron microscopy ; Crystalline lens ; Microphthalmos
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The surface features of cortical fibers from lenses of normal adult rats and microphthalmic rats of the Browman strain have been studied by scanning electron microscopy. In the normal lenses, superficial cortical fibers follow a straight course from inner to outer pole whereas the deeper cortical fibers, while straight near the poles, pursue an undulating or zig-zag course at and near the equator. Almost all of the fibers are hexagonal in cross section and all fibers throughout their entire length are bound by interdigitating processes at each corner of the hexagon to corners of two adjacent fibers. Some fibers are also affixed by a single row of ball and socket junctions located on their broad outer and inner surfaces. Lens fibers from Browman rats display both minor and major abnormalities. These included segmentation, formation of incisures and lateral protrusions, corrugation and villous-like alteration of the broad fiber surface and development of parallel ridges on broad surfaces in a basket-weave pattern.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215175
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 75
    Electronic Resource
    Electronic Resource
    Scanning electron microscopy of photoreceptor cells in the light- and dark-adapted retina of Haplochromis burtoni (Cichlidae, Teleostei) (1976)
    Springer
    Cell & tissue research 175 (1976), S. 123-130 
    Details
    ISSN: 1432-0878
    Keywords: Retina ; Haplochromis burtoni ; Photoreceptor cells ; Light-adaption, dark-adaption ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The photoreceptor layer in the retina of Haplochromis burtoni (Cichlidae, Teleostei) was studied by scanning electron microscopy. Three types of receptors were identified: rods, single-cones and double-cones. The three-dimensional arrangement of these photoreceptors is described in the light- and dark-adapted retina. The surface of the inner segment of the photoreceptor cells displays fine vertical fissures which give rise to slender processes. These so called calycal processes which are of different lengths in rods and cones, surround the beginning of the smooth-surfaced outer segment. The myoid, the contractile part of the receptor, which is located beneath the ellipsoid, was examined in the single-cones of the dark-adapted retina. It is a slender structure with surface infoldings. The myoid, studied by transmission electron microscopy, contains bundles of parallel myofilaments, which are thought to be contractile.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220828
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 76
    Electronic Resource
    Electronic Resource
    The salivary glands of the cockroach Nauphoeta cinerea (Olivier) (1978)
    Springer
    Cell & tissue research 187 (1978), S. 525-534 
    Details
    ISSN: 1432-0878
    Keywords: Salivary glands ; Insects ; Innervation ; Light microscopy ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The innervation of the salivary gland of the cockroach Nauphoeta cinerea (Olivier) has been investigated with the use of light and scanning electron microscopy. Light microscopy of methylene blue stained glands reveals the presence of a dual innervation arising from the ventral nerve cord and the stomodeal nervous system; the principal innervation is that from the ventral nerve cord which passes to the gland via the reservoir ducts. Branches of these nerves form a plexus on the acinar surface, the axons of which exhibit swelling at irregular intervals. The presence of this surface plexus and the axonal swellings was confirmed by scanning electron microscopy both in normal glands and in those in which the basal lamina had been removed by means of an HCl-collagenase digestion method. No acinar plexus was seen to be formed by branches of the stomatogastric nerve that were associated with the gland. However, other branches of this nerve were clearly connected with a complex network of multipolar neurones on the surfaces of the anterior regions of both salivary reservoirs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00229617
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 77
    Electronic Resource
    Electronic Resource
    The human rete testis (1978)
    Springer
    Cell & tissue research 189 (1978), S. 409-433 
    Details
    ISSN: 1432-0878
    Keywords: Rete testis ; Human ; Histophysiology ; Chordae retis ; Scanning electron microscopy ; Transmission electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The human rete testis was examined with regard to 1) the number and distribution of entrances of seminiferous tubules, 2) the light microscopic topography and 3) details of the passages as revealed by scanning and transmission electron microscopy. In a newborn 1474 entrances were counted, approximately 50 % entering from the right and 50 % from the left of the central long axis. Three major subdivisions of the rete were distinguished and described: a septal (or interlobular) part represented by tubuli recti, a tunical (or mediastinal) part which is a true network of channels, and an extratesticular part characterized by dilatations (up to 3 mm wide) which we have called bullae retis. In SEM, cylindrical strands running from wall to wall in the tunical and extratesticular rete spaces are a prominent feature. We have called these chordae retis. They are covered by epithelium and are 5–40 μm wide and 15 to more than 100 μm long. They contain a peculiar tissue consisting of central myoid cells in a fibroelastic matrix. The smaller chordae are avascular. In the light of these findings the rete is interpreted as a highly complex myoelastic sponge. Its function is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00209130
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 78
    Electronic Resource
    Electronic Resource
    Model of skin vascularization in Rana esculenta L.: Scanning electron microscopy of microcorrosion casts (1978)
    Springer
    Cell & tissue research 191 (1978), S. 539-548 
    Details
    ISSN: 1432-0878
    Keywords: Frog skin ; Respiratory capillaries ; Capillary networks ; Microcorrosion casts ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Microcorrosion casts of blood vessels in the skin of Rana esculenta L. were examined by means of scanning electron microscopy with particular reference to the subepidermal network of respiratory capillaries. Due to the fact that arteries and veins lie in the deeper layers of the stratum spongiosum of the corium, the respiratory vessels form a morphologically homogeneous network. Functionally, however, this network is subdivided into small areas with a centripetal direction of blood flow. The deep capillary net, situated at the base of the stratum compactum of the corium, is not so dense as the respiratory network and does not directly communicate with it. Alveolar glands of the skin have no effect on the distribution of capillaries in the two networks.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219816
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 79
    Electronic Resource
    Electronic Resource
    Scanning electron microscopy of peripheral blood leukocytes of the chicken (1979)
    Springer
    Cell & tissue research 204 (1979), S. 147-153 
    Details
    ISSN: 1432-0878
    Keywords: Granulocytes ; Lymphocytes ; Monocytes ; Scanning electron microscopy ; Chicken
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Polymorphonuclear leukocytes, e.g., neutrophilic granulocytes, were enriched from heparinized blood by a Ficoll-step-gradient centrifugation procedure. Scanning electron microscopy (SEM) revealed a surface morphology of narrow ridge-like profiles and small ruffles with occasional microprocesses. Mononuclear leukocytes were isolated by centrifugation over a Ficoll-Metrizoat gradient. The lymphocytes showed varying numbers of microvilli of different length, size and shape. B lymphocytes, characterized by their capability of “sheep red blood cell (SRBC)-rosette formation”, displayed a similar surface morphology. Completely smooth lymphocytes, described in the literature as T lymphocytes, could not be detected, although many lymphocytes with few microprocesses were observed. Thus, SEM is not a useful tool for distinguishing between B and T lymphocytes in the peripheral blood of chickens. Monocytes were characterized by prominent membrane-like ruffles, but in some cases they closely resembled granulocytes. An influence of the various separation media on the surface morphology of the isolated cells could not be detected when compared with cells isolated by the buffy-coat method.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00235171
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 80
    Electronic Resource
    Electronic Resource
    Scanning electron microscopy of the renal corpuscle of the mesonephros in the lamprey, entosphenus japonicus martens (1978)
    Springer
    Cell & tissue research 187 (1978), S. 105-113 
    Details
    ISSN: 1432-0878
    Keywords: Mesonephros ; Lamprey ; Renal corpuscle ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The renal corpuscle of the lamprey mesonephros was studied under the scanning electron microscope. Bowman's capsules with individual spaces are chockshaped sacs closely packed together along a medial artery. The lateral walls of the capsules are apposed to those of neighbouring capsules. Glomerular capillaries from the medial artery extend radially between the apposed walls of neighbouring Bowman's capsules. Bulgings of capillaries into the capsular space are associated with mesangial folds of the capsular epithelium. The transitional zone of the visceral layer with podocytes and the parietal layer of squamous epithelium is bounded by linearly arranged rod-shaped epithelial cells. Apertures of the urinary tubule are lined by cells equipped with a fascicle of cilia.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220622
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 81
    Electronic Resource
    Electronic Resource
    Cytochalasin B and water transport (1978)
    Springer
    Cell & tissue research 188 (1978), S. 375-388 
    Details
    ISSN: 1432-0878
    Keywords: Urinary bladder ; Skin ; Toad, frog ; Water flow ; Na transport ; Vasopressin ; Cytochalasin B ; Microfilaments ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A morpho-functional study of the effects of cytochalasin B (CB) on Na and water transport was made in amphibian epithelia. The functional studies confirmed the dissociation of the natriferic and hydrosmotic effects of vasopressin in toad urinary bladders exposed to CB and showed in addition that the block of the hydrosmotic effect was reversible and could still be induced in epithelia maximally stimulated with the hormone. Scanning electron microscopy revealed that CB, per se, did not alter the apical surface of the bladders. An almost total loss of microvilli of granular cells was seen, however, if CB was associated with vasopressin and an osmotic gradient. The results suggest two points: a) the block of the hydrosmotic flow induced by CB is due to factors beyond the apical membrane; b) microfilaments may be important mechanochemical transducers in the chain of events leading to the hydrosmotic effect of vasopressin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219779
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 82
    Electronic Resource
    Electronic Resource
    On the development of midpiece mitochondria of mouse spermatozoa (1979)
    Springer
    Cell & tissue research 199 (1979), S. 349-352 
    Details
    ISSN: 1432-0878
    Keywords: Spermatozoa ; Mitochondria ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary As seen by scanning electron microscopy, the mitochondrial helix in the developing midpiece of mouse testicular spermatozoa is dextral in direction and consists of spherical mitochondrial units arranged in an orderly array of four units per gyre: three appearing in face view and a fourth hidden from view at the back of the gyre. As the spermatozoa mature, the dextral helix is transformed into a sinistral helix. Its constituent spherical mitochondria either change direction abruptly without changing shape; or having first become semilunar or diamond-shaped, they change direction gradually. Mitochondrial division follows the change in helical pitch producing a double sinistral helix. The spherical (or semilunar/diamond-shaped) mitochondria presumably elongate to form the units of the mature midpiece.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00236144
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 83
    Electronic Resource
    Electronic Resource
    Scanning electron microscopic study of the freeze-fractured pineal body of the rat (1979)
    Springer
    Cell & tissue research 201 (1979), S. 129-135 
    Details
    ISSN: 1432-0878
    Keywords: Pineal body ; Freeze-fracturing ; Scanning electron microscopy ; Wistar rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The three-dimensional ultrastructure of the pineal body of the rat is described on the basis of freeze-fractured preparations. The pineal capsule consists of irregular cells with very flat and perforated processes. Through these openings, extremely branched canaliculi, extending to almost every pineal cell, communicate with the tissue compartment outside the organ. The pericapillary spaces contain, in juxtaposition with capillaries of the fenestrated type, nerve fibers as well as a flocculent granular and filamentous material of unknown origin and chemical nature.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00238052
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 84
    Electronic Resource
    Electronic Resource
    Scanning electron microscopy of the wall of the third ventricle in the brain of Rana temporaria. Part IV. (1979)
    Springer
    Cell & tissue research 203 (1979), S. 53-64 
    Details
    ISSN: 1432-0878
    Keywords: Brain ; Third ventricle ; Rana temporaria ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The surface specializations of the wall of the third cerebral ventricle of Rana temporaria were investigated with the scanning electron microscope. These specializations can be divided into three types: cilia, large bulbous protrusions, and microvillus-like protrusions. Most parts of the ventricular surface are densely ciliated. In contrast, other regions are either scantily ciliated or devoid of cilia. Four areas of the ventricular surface are studded with numerous large bulbous protrusions. These large protrusions can be divided into two types: One type consists of intraventricular end bulbs of dendrites of secretory neurons. The other type is represented by large cytoplasmic extensions of ependymal cells. In the third ventricle of Rana, microvillus-like surface specializations of ependymal cells are ubiquitous structures. Generally, filiform protrusions of varying length are the predominant type. The microvillus-like specializations are transient structures, the number of which varies according to different physiological states of the ependymal cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234328
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 85
    Electronic Resource
    Electronic Resource
    Attraction of nematodes to metabolites of yeasts and fungi (1979)
    Springer
    Journal of chemical ecology 5 (1979), S. 909-918 
    Details
    ISSN: 1573-1561
    Keywords: Attractants ; nematodes ; Panagrellus redivivus ; Rhabditis oxycerca ; Saccharomyces cerevisiae ; predacious fungi ; methyl acetate ; ethyl acetate ; propyl acetate ; butyl acetate ; amyl acetate ; ethyl formate ; propyl formate ; amyl formate ; ethyl propionate ; sodium methyl dithiocarbamate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The free-living nematodesPanagrellus redivivus andRhabditis oxycerca are strongly attracted to methyl, ethyl, propyl, butyl, and amyl acetate, to ethyl, propyl, and amyl formate and to ethyl propionate, but all the respective alcohols and acids are without effect. No loss of attraction is observed when the attractants are combined with lethal concentrations of the commercial nematicide sodium methyl dithiocarbamate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00990213
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 86
    Electronic Resource
    Electronic Resource
    The surface fine structure of the ependymal lining of the lateral ventricle in rats with hereditary hydrocephalus (1977)
    Springer
    Cell & tissue research 179 (1977), S. 121-129 
    Details
    ISSN: 1432-0878
    Keywords: Lateral ventricle, rat ; Hydrocephalus ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ependyma of the lateral ventricle of rats with hereditary hydrocephalus was studied using scanning electron microscopy. Normal rats from the same litters were used as control animals. The surface morphology of the lateral ventricle of normal rats corresponded to results reported by other authors. The most prominent changes in the surface morphology of the ependyma of the hydrocephalic rats were seen in the cilia. They were shortened, fewer in number and clumped or matted. The surface of the ependymal cells was flattened and contained small, irregular projections. The number of large supraependymal cells, regarded as neurons, appeared to have diminished in the hydrocephalic rats. The number of supraependymal macrophages was greatly increased in these rats, suggesting the existence of an ependymitis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00278467
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 87
    Electronic Resource
    Electronic Resource
    Ciliary function of the frog oro-pharyngeal epithelium (1977)
    Springer
    Cell & tissue research 178 (1977), S. 267-278 
    Details
    ISSN: 1432-0878
    Keywords: Ciliated epithelium, frog ; Cilia ; Coordination ; Mucous transport ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The palate epithelium of the frog was examined by scanning electron microscopy, light microscopy and high speed cine micrography. The cilia remain stationary for much of the time in the end-of-effective stroke position. Each beat cycle begins with a forwardly-directed recovery stroke lasting about 60 ms, followed by an effective stroke towards the oesophagus lasting about 12 ms. Activity can often be correlated with the presence of mucus, which is carried as strands on the tips of the ciliary effective strokes whilst the recovery strokes move beneath the mucus. Coordination of ciliary activity was very variable; local antiplectic metachrony of the recovery strokes could almost always be seen, and on very active epithelia effective strokes were associated with approximately diaplectic waves (either to left or right), but any particular pattern of coordinated activity was transient and quickly transformed to another pattern. Beating and coordination of these short cilia were compared with those of cilia propelling water.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219053
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 88
    Electronic Resource
    Electronic Resource
    Surface morphology of taste buds in catfish barbels (1977)
    Springer
    Cell & tissue research 178 (1977), S. 375-384 
    Details
    ISSN: 1432-0878
    Keywords: Taste buds ; Fishes ; Neuroepithelium ; Microvilli ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary External taste buds abound on barbels of the adult catfish Corydoras arcuatus. When examined by scanning electron microscopy, they are visualized as a series of punctate, conical elevations projecting from the general surface epithelium. All taste buds were found to be of one type. Both their external and internal surface features could be clearly elucidated on intact barbels and in barbels fractured transversely at various positions along their length. An extensive nerve terminal network penetrates the base of each taste bud. Two populations of elongated cells bearing prominent microvilli project through the central pore at the tip of each bud. One set of microvilli is thicker, longer and more club-shaped than its counterpart. While both are randomly distributed within each central pore, the small, short microvilli appear to outnumber the larger ones. A third population of cells, devoid of any apical microvilli, was also seen in some of the taste buds examined internally. These cells do not project to the external surface and are interpreted as “basal” cells described in previous light and transmission electron microscope studies of taste buds in other vertebrate species. The functional significance of some of these morphological findings is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218701
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 89
    Electronic Resource
    Electronic Resource
    Vascularization of the pars distalis of the hypophysis in the toad, Bufo bufo (L.) (Amphibia, Anura) (1977)
    Springer
    Cell & tissue research 179 (1977), S. 1-10 
    Details
    ISSN: 1432-0878
    Keywords: Hypophysis, pars distalis ; Bufo bufo (L.) ; Vascularization ; Corrosion casts ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The vascularization of the pars distalis of the hypophysis of the toad, Bufo bufo (L.), was studied by the traditional method of injecting a mixture of India-ink and gelatine into the circulatory system of the head via the arteria carotis communis. Further, methyl-methacrylate corrosion casts of the brains were made; the hypothalamo-adenohypophysial region of these corrosion casts was studied with the scanning electron microscope. The results showed that the portal vessels which arise from the median eminence do not supply distinct areas in the pars distalis as is supposed by the point-to-point-hypothesis. The portal vessels enter the ventro-median region of the pars distalis and branch off into a three-dimensional network of the secondary capillary plexus of the pars distalis. The plexus is made up mostly by four- to six-sided meshes. This angioarchitecture guarantees an optimal supply of the glandular cells of the pars distalis with nutritional factors and releasing hormones, on the one hand, and facilitates the removal of the hormones which are released by these cells, on the other hand. The venous drainage of the pars distalis is exerted mainly by two large veins, which bilaterally leave the dorso-lateral region (venous pole) of the pars distalis and by a few small veins, which drain into the wide, sinus-like vessel, which curves around the dorso-caudal region of the pars distalis and joins bilaterally the vena hypophysea transversa.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00278459
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 90
    Electronic Resource
    Electronic Resource
    A scanning electron microscopic survey of the brain ventricular system of the female armadillo (1977)
    Springer
    Cell & tissue research 183 (1977), S. 531-539 
    Details
    ISSN: 1432-0878
    Keywords: Brain ventricles ; Armadillo ; Ependyma ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The scanning electron microscope was used to survey the brain ventricular system of the female armadillo (Dasypus novemcinctus) with emphasis on the third ventricle. The walls of the lateral ventricles, aqueduct, and fourth ventricle are covered by long cilia. In the lateral ventricle, the cilia are arranged in groups; but in the aqueduct and fourth ventricle, they are evenly placed over the cellular surfaces. The ependymal cells of the third ventricle are densely ciliated except for the organum vasculosum and infundibular recess. The non-ciliated luminal surface of these areas has a pebblestone appearance punctuated by numerous microvilli and two types of supraependymal cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00225665
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 91
    Electronic Resource
    Electronic Resource
    Discocilia—A new type of kinocilia in the larvae of Lanice conchilega (Polychaeta, Terebellomorpha) (1978)
    Springer
    Cell & tissue research 187 (1978), S. 271-280 
    Details
    ISSN: 1432-0878
    Keywords: Kinocilia ; Discocilia ; Lanice conchilega ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Ein modifizierter Typ von Kinocilien wurde bei der Aulophoralarve des sedentären Polychäten Lanice conchilega gefunden. Für ihn wird die Bezeichnung „Discocilium” vorgeschlagen. Der einzige strukturelle Unterschied zu konventionellen Kinocilien besteht in der Ausbildung eines Köpfchens. Dieses Köpfchen wird vom distalen Ende des Cilienschaftes gebildet, der zu einer Öse gebogen ist, die von der Cilienmembran überzogen wird. Drei Haupttypen von Discocilien können unterschieden werden: a, Cilien mit geradem Axonem, deren Köpfchen durch eine Anschwellung der Membran entstehen, b, Cilien mit Köpfchen mit seitlichem gebogenem Axonem, c, Cilien, in denen das Axonem eine geschlossene Öse bildet. Die Discocilien sind nach dem verbreiteten 9+2 Filamentmuster aufgebaut. Ihr Köpfchen enthält keine Sekrete, es erscheint elektronenoptisch leer. Aufgrund ihrer Anordnung können zwei Typen von Discocilien unterschieden werden, nämlich isolierte Büschel, besonders am Vorderende, und segmentai angeordnete Cilienreihen. Ein möglicher Bildungsmodus der Discocilien wird beschrieben.
    Notes: Summary A modified type of kinocilia has been found in the Aulophora-larva of the sedentarian polychaete Lanice conchilega. For this newly described cilium type the term “discocilium” is proposed. The only structural difference from usual locomotory cilia is the tip, which possesses a discoidal head. The head is formed from the terminal part of the cilium shaft, which is bent to give rise to a loop-like ring covered by the ciliary membrane. Three types of discocilia can be distinguished: a) discocilia having swollen, bulblike heads with a central straight axoneme; b) discocilia having heads with a curved lateral axoneme and c) discocilia in which the axoneme forms a loop. The internal structure shows the usual 9+2 arrangement of the filaments. The head shows no signs of secretion; it appears structureless in electron microscopical examination. There are two kinds of discocilia arrangements: 1) isolated bunches of cilia especially at the tentacles and in the frontal region, and 2) segmental dorsal rows of cilia. The possible formation of discocilia is described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00224370
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 92
    Electronic Resource
    Electronic Resource
    Scanning electron microscopic analysis of the linings of the fourth ventricle in the domestic fowl (1979)
    Springer
    Cell & tissue research 197 (1979), S. 169-173 
    Details
    ISSN: 1432-0878
    Keywords: Fourth ventricle ; Ependyma ; Scanning electron microscopy ; Domestic fowl
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Surface features of the ependymal linings of the fourth ventricle in the fowl were analyzed employing the scanning electron microscope (SEM). On the floor of the median sulcus, each ependymal cell has a solitary cilium, whereas on both sides of the sulcus, cilia are so densely distributed that the details of the underlying cell surface are usually obscured. On the roof of the fourth ventricle, except for the surface of the ciliated groove where numerous cilia are present, the ependymal cells are polygonal in shape, and the center of each cell possesses an aggregate of ten to twenty cilia. Cell surfaces of the choroid tela are entirely covered with delicate microvilli and possess clumped cilia. The ependymal cell surfaces of the area postrema are dome-like in shape. Each ependymal cell has a solitary cilium and shows a smooth surface free of microvilli.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00233562
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 93
    Electronic Resource
    Electronic Resource
    Electron microscopic studies on radular tooth formation in the snails Helix pomatia L. and Limax flavus L. (Pulmonata, Stylommatophora) (1979)
    Springer
    Cell & tissue research 203 (1979), S. 283-289 
    Details
    ISSN: 1432-0878
    Keywords: Radula ; Tooth formation ; Pulmonates ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The radular teeth are secreted at the posterior end of the radular gland and move slowly towards the buccal cavity where they start to function. Helix pomatia and Limax flavus were examined to determine whether the newly formed teeth already show their definite species specific shape, or whether they are gradually finished and moulded in the radular gland. Scanning electron micrographs of Helix pomatia show that teeth are secreted in the odontoblast region in their final form. Their surface is still uneven at the outset; the same is true for the newest teeth of Limax flavus. Older teeth ready for use have a smooth surface. This change seems to be brought about by secretory activity of the superior epithelium of the radular sac. Air-dried radulae, previously isolated by KOH maceration, show considerable artefacts at their posterior end. Maceration leads to shrinking of the newest teeth, but does not change their contours. The newly secreted but as yet unhardened teeth become greatly deformed during the drying process.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00237242
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 94
    Electronic Resource
    Electronic Resource
    The surface connected canalicular system of carp (Cyprinus carpio) thrombocytes: Its fine structure and three-dimensional architecture (1979)
    Springer
    Cell & tissue research 203 (1979), S. 355-365 
    Details
    ISSN: 1432-0878
    Keywords: Fish thrombocyte ; Open canalicular system ; Three-dimensional architecture ; High voltage electron microscopy ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The presence and the three dimensional distribution of the surface connected canalicular system (SCCS) in thrombocytes of a teleost, Cyprinus carpio, were studied using a transmission electron microscope, a high voltage electron microscope and a scanning electron microscope. When the specimens were fixed routinely in glutaraldehyde followed by osmium tetroxide, numerous electron lucent vesicles and canaliculi were distributed throughout the cytoplasm. As ruthenium red-positive reaction product was observed on the inner surface of the vesicles and canaliculi, these are defined as the SCCS of carp thrombocytes. In the stereo-pair of the photographs of thick sectioned specimens and the plastic reconstruction of serially sectioned thrombocytes, we succeeded in finding the whole structure of the SCCS which is composed of numerous anastomosing canaliculi. Scanning electron micrographs revealed many crater-like depressions throughout the cell surface which seem to be the openings of the SCCS.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00233264
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 95
    Electronic Resource
    Electronic Resource
    Surface changes during development and involution of the cement gland of Xenopus laevis (1978)
    Springer
    Cell & tissue research 194 (1978), S. 303-313 
    Details
    ISSN: 1432-0878
    Keywords: Cement gland ; Xenopus laevis ; Secretion ; Mucus ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The cement gland was studied from stage 17, when the anlage is established, to stage 49, shortly before its disappearance. At early stages, the apical membrane is covered by small microvilli that are more abundant than in the surrounding epiblast cells. Vesicular protrusions along the cell boundaries are also more numerous in the gland cells. When the gland reaches maturity, the apical membranes of gland cells differentiate into two regions. In the cranial, kidney-shaped region, the membranes are very narrow and protrude above the level of cell boundaries. Long and slender villi raise from the surface adjacent to cell boundaries. Apical surfaces in the caudal portion are larger and flattened. Cell boundaries are lined with shorter and thicker surface projections. At these stages, the bordering cells are covered with secretion vesicles. During involution the number of cells is progressively reduced. The area of the caudal portion increases relative to the area of the cranial portion. Apical surfaces become more flattened. Surface projections become much shorter and invade the whole of the apical surface. Bordering cells lose their secretion vesicles and their apical surface becomes ruffled with numerous short wrinkles. The significance of the apical structures and their evolution is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220397
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 96
    Electronic Resource
    Electronic Resource
    Scanning electron microscopy of the respiratory surfaces of Saccobranchus (=Heteropneustes) fossilis (Bloch) (1978)
    Springer
    Cell & tissue research 195 (1978), S. 99-109 
    Details
    ISSN: 1432-0878
    Keywords: Gills ; Air-breathing organs ; Catfish, Saccobranchus fossilis ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The gill secondary lamellae are generally covered with epithelial cells whose outer surfaces form numerous microvilli. The surface of the primary lamellae is characterised by microridges. A particular type of surface sculpturing seems to be associated with given cell boundaries. Further evidence for the derivation of the air tube and fans which guard its entrance by modification of the basic gill structure has been obtained from both the gross surface architecture and microstructure of the individual cell surfaces. Secondary lamellae are represented by stubby projections which generally have a biserial arrangement. The outer surfaces of the epithelia overlying the capillaries of these respiratory islets are coated with microvilli as in the secondary lamellae. On the other hand, the relatively smooth-surfaced ‘lanes’ between groups of respiratory islets have a microridged surface similar to that of the primary gill lamellae. It is suggested that previous estimates of surface area, and consequently diffusing capacities of the air-breathing organ, have been low in view of the increased surface, due to both their gross and microstructure. Estimates for gill surface area may need very little correction as the spaces between the microvilli and microridges are probably filled with mucus under normal conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00233679
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 97
    Electronic Resource
    Electronic Resource
    Scanning electron microscopy of microcorrosion casts of the vascular bed in the skin of the spotted salamander, Salamandra salamandra L. (1979)
    Springer
    Cell & tissue research 196 (1979), S. 153-162 
    Details
    ISSN: 1432-0878
    Keywords: Salamander skin ; Skin capillaries ; Poison gland capillaries ; Microcorrosion casts ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Microcorrosion casts of blood vessels in the skin of the spotted salamander, Salamandra salamandra L., were studied using scanning electron microscopy. The investigated vessels include a subepidermal network of respiratory capillaries and the vessels of poison glands. A hypothesis is proposed, according to which both types of vascular beds possess a common origin. Probable factors involved in the differentiation of the primary netword of the subepidermal vessels in larvae are indicated and speculation concerning the supposed mosaic type of circulation in the capillaries of the subepidermal respiratory bed is presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00236356
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 98
    Electronic Resource
    Electronic Resource
    Observations on the marginal ruffles of an established fibroblast-like cell line (1977)
    Springer
    Cell & tissue research 179 (1977), S. 225-234 
    Details
    ISSN: 1432-0878
    Keywords: Marginal ruffles ; Fibroblast-like cells ; Scanning electron microscopy ; Transmission electron microscopy ; Light microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary LW13K2 cells, a clone of a spontaneously in vitro transformed derivative of embryonic Lewis rat fibroblastic cells, were studied by phase contrast cine-light microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The ruffles found at the advancing edge of cells grown on glass substrates in vitro form and recede in a period of less than one min if they do not make an attachment of the substrate. If they fail to make an attachment they may form pinocytotic channels near the leading edge as described by Price (1972) and/or collapse, generally backwards, towards the cell body. The ‘spines’ which appear to reinforce the membranous ruffles are the last structures to disappear, and accumulate in an irregular array behind the ruffling edge; this area is behind that in which pinocytosis occurs. In comparison with the sparse numbers of ribosomes found in the trailing edge, they are present in notable concentrations near the leading, ruffling edge of the cell. No membrane vesicles have been found in or near the ruffling edges at the ruffle-spine concentration zone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219798
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 99
    Electronic Resource
    Electronic Resource
    The outer segments of photoreceptive pinealocytes in the pineal organ of the funa, Carassius gibelio langsdorfi (1978)
    Springer
    Cell & tissue research 186 (1978), S. 259-268 
    Details
    ISSN: 1432-0878
    Keywords: Pineal organ ; Carassius gibelio langsdorfi (Teleostei) ; Photoreceptive cell ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The form and size of the outer segments of photoreceptive pinealocytes in the pineal organ of the funa, Carassius gibelio langsdorfi, were observed with the scanning electron microscope. The height of the outer segments measures between 1 and 3 μm and the diameter varies widely from 1.5 to 8 μm. Various forms of outer segments, i.e. a slender type, a dome-like type, a cap-like type and a helical type, were demonstrated. The parallel-oriented filamentous processes of the inner segments have the same length as the outer segments and a diameter of approximately 100 nm; they are projections from the apical border of the inner segment and surround the cone-like outer segments. The processes make a right angle with the lamellar disks. The distance between two processes averages 100 nm. The lamellar disks of the outer segments are oriented at right angles to the modified cilium in the basal part, but the angle often changes in the peripheral part, where the lamellar disks are raised and become parallel to the cilium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00225535
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 100
    Electronic Resource
    Electronic Resource
    Fenestration of the epithelium lining the roof of the fourth cerebral ventricle in amphibia (1979)
    Springer
    Cell & tissue research 198 (1979), S. 129-136 
    Details
    ISSN: 1432-0878
    Keywords: Cerebral ventricles ; Ependyma ; Pores ; Subarachnoid space ; Scanning electron microscopy ; Amphibia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Scanning electron microscopy of the caudal end of the roof of the fourth cerebral ventricle in four amphibian species shows that numerous pores occur between the ependymal cells. These pores have diameters ranging from 5–100 μm; they permit bulk flow of cerebrospinal fluid out of the ventricular system into the subarachnoid space.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234840
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...