GLORIA

GEOMAR Library Ocean Research Information Access

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
  • 2015-2019  (1)
  • 1995-1999  (3)
  • 1975-1979  (6)
  • 1965-1969  (7)
  • 1
    Electronic Resource
    Electronic Resource
    Patterns of spiral tip motion in cardiac tissues (1998)
    Woodbury, NY : American Institute of Physics (AIP)
    Chaos 8 (1998), S. 137-148 
    Details
    ISSN: 1089-7682
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In support of the spiral wave theory of reentry, simulation studies and animal models have been utilized to show various patterns of spiral wave tip motion such as meandering and drifting. However, the demonstration of these or any other patterns in cardiac tissues have been limited. Whether such patterns of spiral tip motion are commonly observed in fibrillating cardiac tissues is unknown, and whether such patterns form the basis of ventricular tachycardia or fibrillation remain debatable. Using a computerized dynamic activation display, 108 episodes of atrial and ventricular tachycardia and fibrillation in isolated and intact canine cardiac tissues, as well as in vitro swine and myopathic human cardiac tissues, were analyzed for patterns of nonstationary, spiral wave tip motion. Among them, 46 episodes were from normal animal myocardium without pharmacological perturbations, 50 samples were from normal animal myocardium, either treated with drugs or had chemical ablation of the subendocardium, and 12 samples were from diseased human hearts. Among the total episodes, 11 of them had obvious nonstationary spiral tip motion with a life span of 〉2 cycles and with consecutive reentrant paths distinct from each other. Four patterns were observed: (1) meandering with an inward petal flower in 2; (2) meandering with outward petals in 5; (3) irregularly concentric in 3 (core moving about a common center); and (4) drift in 1 (linear core movement). The life span of a single nonstationary spiral wave lasted no more than 7 complete cycles with a mean of 4.6±4.3, and a median of 4.5 cycles in our samples. Conclusion: (1) Patently evident nonstationary spiral waves with long life spans were uncommon in our sample of mostly normal cardiac tissues, thus making a single meandering spiral wave an unlikely major mechanism of fibrillation in normal ventricular myocardium. (2) A tendency toward four patterns of nonstationary spiral tip motion was observed. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.166294
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Symbiosis in the Larger Foraminiferan Sorites marginalis (with Notes on Archaias spp.) (1976)
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 23 (1976), S. 0 
    Details
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SYNOPSIS. It was demonstrated with the aid of light and electron microscope studies that Sorites marginalis (Lamarck) harbors zooxanthellae. The hosts were scraped from Thalassia testudinum Konig growing in Key Largo Sound (Florida, U.S.A.) and immediately preserved in appropriate fixatives. Zooxanthellae were distributed unevenly throughout all the chamberlets; only a few symbiotes were found in the embryonic chambers and the inner or outer chambers, but the intermediate chambers were packed with symbiotes. The outer chambers contained many food vacuoles in addition to symbiotes. Some zooxanthellae might have been in the process of degeneration or digestion. The symbiotes were found to have a typical dinoflagellate nucleus, a single large lobate cortical chloroplast with one stalked pyrenoid, an accumulation body, and many starch granules. The nonmotile stage of the zooxanthella was similar, but perhaps not identical, to Symbiodinium microadriaticum Freudenthal from various hosts.The foraminiferan host is heterokaryotic with hundreds of generative (small) nuclei and scores of vegetative (large) nuclei. Most of the generative nuclei were found in the embryonic apparatus and the inner chambers. Most of the vegetative nuclei were found in the inner and outer chambers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1550-7408.1976.tb03793.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Allogromia laticollaris: A Foraminiferan with an Unusual Apogamic Metagenic Life Cycle (1976)
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 23 (1976), S. 0 
    Details
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SYNOPSIS. The life cycles of 3 strains of Allogromia laticollaris, a monothalamous foraminiferan, have been studied. Each of the strains had a different, nonclassical, and basically apogamic, life cycle. The Cold Spring Harbor (CSH) strain regularly alternated between 2 agamontic forms: agamont I (uninucleate and diploid) and agamont II (multinucleate and diploid). The complete life cycle took 26 days. Sexual reproduction was rare (0.01%) and autogamous. Small numbers of organisms also underwent budding, binary fission, and cytotomy. The life cycles of the Towd Point (TPA) and Sippewissett (SIP) strains were comparatively abbreviated. Agamont II dominated their typical life cycles, which were completed in 16-18 days. The life cycle of SIP was basically a continuous cycling of the agamont II phase. Approximately 75% of the schizozoites of the TPA strain developed into agamont II. The other 25% alternated between agamont II and agamont I phase.In the CSH strain schizozoites with ∼ 8 (range 5-15) nuclei characterized newly formed agamonts II. More nuclei (∼ 25) were found in the other 2 strains. The nuclei in young agamonts II underwent rapid morphologic changes leading to a “mushroom-like” chromosome appearance and extensive RNA synthesis. Nucleolar material accumulated at the nuclear periphery and eventually was discharged to the cytoplasm. Karyokinesis took place without the breakdown of the nuclear membrane.The single nucleus of young agamont I forms was proportionally quite large. The S1 phase occurred quite early (2-5 days) in this part of the life cycle. RNA in the CSH strain formed a compact, subcortical, coarsely granular ring, while in the TPA it was cortical and differentiated into finely granular matrix with randomly distributed coarse granules. During the G2 phase the nucleus became further enlarged and eventually amoeba-form. Intermediate stages in nuclear breakdown were not found.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1550-7408.1976.tb05251.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Tracer Experiments in Feeding Littoral Foraminifera (1966)
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 13 (1966), S. 0 
    Details
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SYNOPSIS. Tracer technic has proved to be an excellent tool in the study of predator-prey relationships among the foraminifera. More than fifty axenic species of protists including diatoms, dinoflagellates, chlorophytes, chrysophytes, cyanophytes, bacteria and yeasts were tested as potential food for Allogromia sp (NF), A. laticollaris, Am. monia beccarii, Quinqueloculina spp, Rosalina floridana, Anomalina sp, Elphidium sp, Spiroloculina hyalina, Globigerina bulloides, and Globorotalia truncatulinoides. Although many types of potential food are present in the environment, foraminifera select only certain organisms. The yeasts, cyanophytes, dinoflagellates, chrysophytes and most bacteria tested were not eaten. Selected species of diatoms, chlorophytes and bacteria were eaten in large quantity. Three additional factors affect feeding: the “age” of the food organism, the “age” of the foraminifer or its position in the life cycle, and the concentration of the food. Feeding by foraminifera on most food is erratic below a concentration of 103 organisms and is approximately directly proportional to concentration within a range of 103-106 organisms per 10 ml experimental tube. A natural bloom of Protelphidium tisburyensis was analyzed. A high concentration of 6 species of diatoms characterized the community. A “bloom”-feeder hypothesis for foraminiferal nutrition is presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1550-7408.1966.tb01978.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    TULP1 mutation in two extended Dominican kindreds with autosomal recessive Retinitis pigmentosa (1998)
    [s.l.] : Nature Publishing Group
    Nature genetics 18 (1998), S. 177-179 
    Details
    ISSN: 1546-1718
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Medicine
    Notes: [Auszug] The RP14 autosomal recessive Retinitis pigmentosa (arRP) locus has been mapped to a 2cM region of chromosome 6p21.3 (refs 1–3). TULP1 (the gene encoding tubby-like protein 1) is a candidate target for the disease mutation because it maps to the RP14 minimum genetic region and because a ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/ng0298-177
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Prolonged Culture of the Voracious Flagellate Peranema in Antioxidant-Containing Media (1966)
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 13 (1966), S. 0 
    Details
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SYNOPSIS. Peranema trichophorum remained vigorous at least a year in milk-lecithin media and 3 months in a nearly defined autoclavable biphasic agar medium fortified with the fat-soluble antioxidant butylated hydroxytoluene. The only undefined substance in the present “defined” medium is crude soybean lecithin; 0.001% lecithin suffices in the presence of a mixture of long-chain saturated and unsaturated fatty acids. Linoleic acid may be indispensable. Histidine is an absolute requirement as well as a favored substrate. Cholesterol, not ergosterol, satisfied the sterol requirement. Voracity is retained in these media as shown by engorgement on plastic latex particles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1550-7408.1966.tb01877.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Hedley, R. H. & Adams, C. B., eds. Foraminifera, Vol. 2 (1977)
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 24 (1977), S. 0 
    Details
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1550-7408.1977.tb04780.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Apparent Indispensability of Bacteria in Foraminiferan Nutrition (1969)
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 16 (1969), S. 0 
    Details
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SYNOPSIS. Bacteria were required for the sustained reproduction of 4 species of foraminifera in gnotobiotic culture. None of the species of algae tested, singly or in combination, supported continuous reproduction of the foraminifera in bacteria-free gnotobiotic culture. It is inferred that bacteria have some nutritional factor required by the foraminifera that is either unavailable or unavailable in sufficient quantity in an exclusively algal diet.Gnotobiotic clones of Quinqueloculina lata, Spiroloculina hyalina, Rosalina leei, and Allogromia laticollaris were established on bacteria + algae (usually 1 or 2 species). In balanced gnotobiotic cultures neither light nor foraminiferan density (organisms/ml) were limiting. As cultures aged, pH shifted and limited growth. When waste products were removed by washing, reproductive rates were higher.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1550-7408.1969.tb02303.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Quantitative Studies on the Growth of Allogromia laticollaris (Foraminifera) (1969)
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 16 (1969), S. 0 
    Details
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SYNOPSIS. The growth and reproduction of Allogromia laticollaris was studied. More schizozoites were generally produced in mixtures of food organisms than on single algal foods. In the presence of moderate numbers of bacteria, cultures with Phaeodactylum tricornutum, Chlorococcum sp., Nannochloris sp., and an unidentified chlorophyte (BL-1), added singly, were also highly productive. Schizogony was the dominant asexual form of reproduction. Binary fission and cytotomy also occurred in bacterized otherwise unfed controls. 35S and 32P are convenient labels for measuring growth of A. laticollaris when introduced into the system in the range of 1 × 104 - 1 × 105 dpm/ml (32P specific activity ∼ 2.03 MCi/g; 35S specific activity ∼ 95 μCi/g). Small allogromiids grew faster than did larger ones. By means of the Taylor series modification of the classical least-squares method, a continuous life-cycle representation was calculated for A. laticollaris for the conditions of the experiment. Four points of cell volume growth were maxima for reproduction: 1.0 × 107μ per organism for curve I; 2.2 × 107μ3 and 1.2 × 107μ3 for curve II; and 6.7 × 107μ3 for curve III.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1550-7408.1969.tb02286.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Biological Interactions and the Realized Niche of Euplotes vannus from the Salt Marsh Aufwuchs (1977)
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 24 (1977), S. 0 
    Details
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SYNOPSIS. Euplotes vannus, a hypotrich ciliate. grows well over broad ranges of temperature and salinity. It requires higher densities of food (〉 1 × 104 cells/ml) for rapid reproduction than do the other herbivores, the foraminiferan Al-logromia laticollaris (〉 1 × 102 cells/ml), and the nematode Chromadorina germanica (∼ 1 × 103 cells/ml), to which it was compared. If food levels were initially very high (∼ 1 × 108 cells/ml) the ciliates reproduced rapidly and consumed the algae faster than it could reproduce. Some balance between the algae and the ciliates was achieved at initial algal concentrations of ∼ 1 × 105 cells/ml. In microcosm experiments at 25 C with equal numbers of C. germanica and A. laticollaris. E. vannus proved to be a very poor competitor; reaching only 20% of control levels when grow with C. germanica and only 13% when cultured with A. laticollaris. It was a better competitor in 2-species microcosms, at lower temperatures, and when its ratio to the other species was initially higher.The experimental evidence suggests that E. vannus is best adapted to being a migrating initial colonizer of fresh algal blooms.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1550-7408.1977.tb01005.x
    Location Call Number Limitation 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...