Library

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
  • Electronic Resource  (5)
  • 1975-1979  (5)
Material
  • Electronic Resource  (5)
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 271 (1978), S. 98-98 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] FOR nearly 30 years from the early 1930s, Sir James Gray and his colleagues at Cambridge published a steady stream of papers analysing how animals move in locomotion. There were distinguished earlier and contemporary contributions by others, but Gray set the foundation for the modern development of ...
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 280 (1979), S. 679-682 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The femoral portion of the RU muscle consists of two bundles of long (1 cm) fibres, called 'red' and 'white', usually containing eight and nine fibres, respectively4'11. Each bundle of fibres is innervated by one of a pair of large ('fast') excitatory motor axons which run in a branch (B2) (rf. 4) ...
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-1017
    Keywords: Cephalopod ; Retina ; Photoreceptor ; Potentials ; Cations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Physics
    Notes: Abstract The ERG of the isolated, superfused half-eye of the cephalopod Sepiola atlantica, evoked by a brief (10 Μs) light flash, has been studied by recording intraretinal potentials with glass microelectrodes. The intensity-response characteristics of the potentials recorded at an electrode fixed at the surface (V s ) can be fitted by a simple equation derived from an equivalent circuit model based on a sodium conductance increase mechanism. Raising the external potassium level reduces the maximal response (δV m ), but does not alter the half-saturation intensity value (I 0). Reducing external sodium does not affect (δV m ), but increases I 0. Reducing external calcium also does not affect (δV m ), but decreases I 0. These effects are adequately described by the model if it is also assumed (a) that changing the external sodium does not significantly alter the transmembrane sodium gradient, and (b) that sodium and calcium ions compete for the sensitivity control mechanism. Differential-depth recording between the fixed electrode at the surface and another electrode that could be moved into the retina revealed that the two component appearance of the transretinal ERG arose from the superposition of two vitreal-negative waveforms. An initial “fast” component was mainly recorded in the photoreceptive distal segments while a “slow” component was prominent in the more proximal regions of the retina. Perfusion with high K+ salines resulted in a decrease in the amplitudes of both fast and slow components of the response whereas reducing external Na+ reduced the amplitude of the fast component at all light intensities but reduced the amplitude of the slow component only at low intensities. The amplitudes of both the fast and slow components increased on reducing external calcium, but the rate of rise and fall of the fast component was independent of external calcium. The rate of rise of the slow component was also independent of the external Ca2+ level but a minimum in the recovery time (t F ) was shifted to a lower intensity value at lower calcium concentrations. The shift of the minimum was to a higher intensity value with lowered sodium perfusing solutions. On the basis of the differential sensitivity of the two components to ion changes, as well as stimulus intensity and intraretinal distribution of the components, it is suggested that they reflect two distinct processes in the light-evoked potential of the photoreceptor cells.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 47 (1977), S. 653-662 
    ISSN: 1573-5036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Growth and P, K, Ca, Mg, Mn, Zn, Fe, and Cu concentrations and contents were determined in Al-tolerant and Al-intolerant corn (Zea mays L.) inbreds when grown at various levels of Al. B57 was more tolerant to Al than was Oh40B. Relatively low Al levels (up to 5 mg/l) enhanced B57 growth but inhibited Oh40B growth. With few exceptions, Oh40B root and leaf concentrations of the elements decreased with added Al. The decreases in element concentrations were not as large for B57 as they were for Oh40B. The Mg concentrations and contents decreased more than the other elements in all inbreds with added Al. Root Mg decreased more than leaf Mg. Total uptake of some elements were higher at low Al than with no Al. Inasmuch as Mg has a pronounced effect on root growth, low Mg may be an important response in plants sensitive to Al.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 48 (1977), S. 509-523 
    ISSN: 1573-5036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The role of Cu in promoting the reproductive phase of growth was examined using Thatcher spring wheat (Triticum aestivum L.). Plants were grown in limed Bladen soil (pH 5.3) in a controlled growth room. The plants were first harvested when five leaves had developed (day 23) and some top leaves of Cu-deficient (-Cu) plants had rolled (withertip) indicating a Cu deficiency. The leaves were shorter on Cu than Cu-sufficient (+Cu) plants, and fewer leaves developed. As they entered the reproductive growth phase, +Cu plants accumulated reducing sugars and reduced 2, 3, 5- triphenyltetrazolium chloride (TTC) in their stems, while Cu plants had lower concentration of the reducing sugars and very little TTC was reduced indicating a reduction in energy and in reducing capacity. Thin-layer-chromatography showed that top leaves of Cu plants contained higher concentrations of aspartic acid, alanine, and serine; and less aminobutyric acid than +Cu plants. Nitrate, P, and K concentrations were higher, and Ca and Cu were lower in Cu than in +Cu plants.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...