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
  • Cyanobacteria  (5)
  • Bone
  • Springer  (8)
  • 1980-1984  (8)
  • 1984  (8)
Collection
Keywords
Publisher
  • Springer  (8)
Years
  • 1980-1984  (8)
Year
  • 1
    Electronic Resource
    Electronic Resource
    What should bones be designed to do? (1984)
    Springer
    Calcified tissue international 36 (1984), S. S7 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; Mechanical function
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The variety of different mechanical functions required of whole bones is discussed. Often, the design optimizing the structure for one function is not optimal for another function.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02406127
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Failure to detect an amorphous calcium-phosphate solid phase in bone mineral: A radial distribution function study (1984)
    Springer
    Calcified tissue international 36 (1984), S. 291-301 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; Mineral ; Amorphous calcium phosphate ; X-ray diffraction ; Radial distribution function
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary X-ray diffraction radial distribution function analysis was used to determine if a significant amount of an amorphous solid phase of calcium phosphate exists in bone, and if so, whether the amount varies as a function of age and maturation. Unfractionated cortical bone from embryonic and posthatch chicks of various ages and a low-density fraction of embryonic bone were studied. No evidence was found for the presence of an amorphous solid phase of calcium phosphate in any of the samples studied, including the recently deposited bone mineral of the low density fraction of embryonic bone. As little as 12.5% of synthetic amorphous calcium phosphate (ACP) added to bone was readily detected by the radial distribution function technique used. The results clearly indicate that the concept that ACP is the initial solid mineral phase deposited in bone, and the major mineral constituent of young bone is no longer tenable. The concept does not provide an accurate description of the nature of the initial bone mineral deposited, or the changes that occur with maturation, nor can it acount for the compositional and X-ray diffraction changes that the mineral component undergoes during maturation and aging.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02405333
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Osmotic adjustment in cyanobacteria from hypersaline environments (1984)
    Springer
    Archives of microbiology 138 (1984), S. 333-337 
    Details
    ISSN: 1432-072X
    Keywords: Cyanobacteria ; Osmotic adjustment ; Osmoregulation ; Quaternary ammonium compounds ; Glycine betaine ; Halotolerance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The intracellular concentrations of the monovalent inorganic cations K+ and Na+, low molecular weight carbohydrates and quaternary ammonium compounds have been determined for 4 strains of cyanobacteria (Aphanothece halophytica, Coccochloris elabens, Dactylococcopsis salina and Synechocystis DUN52) originally isolated from hypersaline habitats (i.e. habitats with a salinity greater than that of seawater) over a range of external salt concentration (from 50% to 400% seawater). Intracellular cation levels (Na+ and K+) were determined to be within the range 80–320 mmol · dm-3 (cell volume), showing only minor changes in response to salinity. Intracellular carbohydrates were found to comprise a negligible component of the intracellular osmotic potential [at 2–19 mmol · dm-3 (cell volume)], throughout the salinity range. Quaternary ammonium compounds, however, were recorded in osmotically significant quantities [up to 1,640 mmol · dm-3 (cell volume)] in these strains, showing major variation in response to salinity. Thus Synechocystis DUN 52 showed an increase in quaternary ammonium compounds in the oder of 1,200 mmol · dm-3 between 50% and 400% seawater medium, accounting for a significant proportion of the change in external osmotic potential. Examination of intact cells and cell extracts using 13C and 1H nuclear magnetic resonance (NMR) spectroscopy confirmed the presence of the quaternary ammonium compound glycine betaine as the major osmoticum in the 4 strains; no other compounds were detected during NMR assays. These results suggest a common mechanism of osmotic adjustment, involving quaternary ammonium compounds, in cyanobacteria from hypersaline environments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00410900
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Surface charge on thylakoid membranes: regulation of photosynthetic electron transfer in cyanobacteria (1984)
    Springer
    Archives of microbiology 138 (1984), S. 54-57 
    Details
    ISSN: 1432-072X
    Keywords: O2 evolution ; Lag-phase ; Membrane surface charge ; Transmembrane H+ electrochemical potential difference ; 9-Aminoacridine fluorescence changes ; Ionophore antibiotics ; Cyanobacteria ; Anabaena variabilis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The establishment of the steady-state rate of photosynthetic O2 evolution by cells of Anabaena variabilis and other cyanobacteria was found to be preceded by a lag-phase the duration of which depended on the time of cell preincubation in the dark. Electron acceptors (benzoquinone, N,N,N′,N′-tetramethyl-p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine or 2,6-dichlorophenolindophenol) abolished the lag-phase as well as the inhibitory effect of cyanide on electron transfer. Mono-, di-and trivalent cations added to the cell suspension markedly reduced the lag-phase. As cation concentrations were increased, acceleration and subsequent deceleration of the O2 evolution rate were observed. The efficient concentrations of cations decreased as their valency increased. The lag-phase and the rate of photosynthetic O2 evolution by the blue-green algae are suggested to depend on the value of the membrane surface charge governing the electrostatic interaction between unidentified membrane-bound redox components. The combination of valinomycin and nigericin as well as gramicidin D enhanced the duration of the lagphase by deenergization of thylakoid membrane.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425407
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Morphology and ultrastructure of the cyanobacterium Mastigocladus laminosus growing under nitrogen-fixing conditions (1984)
    Springer
    Archives of microbiology 137 (1984), S. 97-103 
    Details
    ISSN: 1432-072X
    Keywords: Cyanobacteria ; Heterocysts ; Utrastructure ; Cytology ; Akinetes ; Mastigocladus laminosus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The morphological and ultrastructural characteristics of the cyanobacterium Mastigocladus laminosus growing under N2-fixing conditions were examined with light and electron microscopy. Vegetative cells in narrow filaments contained randomly arranged segments of thylakoid membrane, centrally located carboxysomes (polyhedral bodies), peripherally located lipid bodies, and large numbers of polysaccharide granules in addition to nuclear material and ribosomes. The ultrastructural characteristics of cells in wide filaments were similar, except for increased numbers of carboxysomes and lipid bodies. Heterocytes and proheterocysts developed at a variety of locations in narrow filaments, wide filaments, and the lateral branches off of wide filaments. Akinetes were not observed in any of the filaments. The morphological characteristics of heterocysts and proheterocysts were variable and depended on those of the vegative cells from which the heterocysts and proheterocysts developed. Mature M. laminosus heterocysts were somewhat similar to those formed in other cyanobacterial genera, but they possessed a number of distinct and unique ultrastructural characteristics, including (i) the absence of a fibrous and, possibly, a laminated wall layer, (ii) the presence many closely packed membranes throughout most of the cytoplasm, and (iii) the presence of unidentified, spherical inclusion bodies of variable electron density.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00414447
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Evidence for an ammonium transport system in free-living and symbiotic cyanobacteria (1984)
    Springer
    Archives of microbiology 137 (1984), S. 241-246 
    Details
    ISSN: 1432-072X
    Keywords: Ammonium transport ; Anabaena azollae ; Anabaena variabilis ; Cyanobacteria ; Methylammonium transport ; Symbiosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The free-living cyanobacterium Anabaena variabilis showed a biphasic pattern of 14CH3NH 3 + uptake. Initial accumulation (up to 60 s) was independent of CH3NH 3 + metabolism, but long-term uptake was dependent on its metabolism via glutamine synthetase (GS). The CH3NH 3 + was converted into methylglutamine which was not further metabolised. The addition of l-methionine-dl-sulphoximine (MSX), to inhibit GS, inhibited CH3NH 3 + metabolism, but did not affect the CH3NH 3 + transport system. NH 4 + , when added after the addition of 14CH3NH 3 + , caused the efflux of free CH3NH 3 + ; when added before 14CH3NH 3 + , NH 4 + inhibited its uptake indicating that both NH 4 + and CH3NH 3 + share a common transport system. Carbonylcyanide m-chlorophenylhydrazone and triphenyl-methylphosphonium both inhibited CH3NH 3 + accumulation indicating that the transport system was Δψ-dependent. At pH 7 and at an external CH3NH 3 + concentration of 30 μmol dm-3, A. variabilis showed a 40-fold intracellular accumulation of CH3NH 3 + (internal concentration 1.4 mmol dm-3). Packets of the symbiotic cyanobacterium Anabaena azollae, directly isolated from the water fern Azolla caroliniana, also showed a Δψ-dependent NH 4 + transport system suggesting that the reduced inhibitory effect of NH 4 + on nitrogenase cannot be attributed to the absence of an NH 4 + transport system but is probably related to the reduced GS activity of the cyanobiont.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00414551
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Can strains give adequate information for adaptive bone remodeling? (1984)
    Springer
    Calcified tissue international 36 (1984), S. S118 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; Strain ; Remodeling ; Adaptation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary For bone to remodel adaptively, the cells responsible should follow some algorithm. Nine different loading situations and structures are discussed. It seems that either algorithm must be extremely complex, or cells in different structures must follow different algorithms.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02406144
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Cell division in baeocyte producing cyanobacteria (1984)
    Springer
    Protoplasma 123 (1984), S. 104-115 
    Details
    ISSN: 1615-6102
    Keywords: Constrictive binary fission ; Cyanobacteria ; Development ; Multiple fission ; Septate binary fission ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary An ultrastructural examination of cell division in two baeocyte producing cyanobacteria,Pleurocapsa minor andDermocarpa violaceae, reveals two distinct patterns of binary (transverse) fission. Septate binary fission, inPleurocapsa minor, involves centripetal synthesis and deposition of the mucopolymer cell wall layer (L 2). The ingrowth of the cytoplasmic membrane and L 1 cell wall layer, along with the synthesis of the L 2 cell wall layer, results in the formation of a prominent septum. Partitioning of the cell occurs by the constriction of the outer cell wall layers (L 3 and L 4) through the septum. InDermocarpa violaceae, constrictive binary fission occurs by the simultaneous ingrowth or constriction of the cytoplasmic membrane and all cell wall layers (L1, L2, L3, L4). Septate and constrictive binary fission may proceed symmetrically (medially) or asymmetrically (nonmedially). Multiple fission occurs regularly inDermocarpa violaceae and provides for a rapid means of reproduction when compared to binary fission. Successive radial and tangential divisions of the protoplast result in formation of many small daughter cells (baeocytes). The process of multiple fission is similar to septate binary fission with reduced septa being formed. However, constriction of the outer cell wall layers, through the septa, proceeds concurrently with septum formation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01283581
    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...