Library

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
  • 1990-1994  (8)
  • 1925-1929
  • 1991  (8)
Source
Material
Years
  • 1990-1994  (8)
  • 1925-1929
Year
Keywords
  • 1
    Electronic Resource
    Electronic Resource
    Lactate Utilization by Isolated Cells from Early Neonatal Rat Brain (1991)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 57 (1991), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: : The utilization of lactate, glucose, 3-hydroxybutyrate, and glutamine has been studied in isolated brain cells from early newborn rats. Isolated brain cells actively utilized these substrates, showing saturation at concentrations near physiological levels during the perinatal period. The rate of lactate utilization was 2.5-fold greater than that observed for glucose, 3-hydroxybutyrate, or glutamine, suggesting that lactate is the main metabolic substrate for the brain immediately after birth. The apparent Km for glucose utilization suggested that this process is limited by the activity of hexokinase. However, lactate, 3-hydroxybutyrate, and glutamine utilization seems to be limited by their transport through the plasma membrane. The presence of fatty acid-free bovine serum albumin (BSA) in the incubation medium significantly increased the rate of lipogenesis from lactate or 3-hydroxybutyrate, although this was balanced by the decrease in their rates of oxidation in the same circumstances. BSA did not affect the rate of glucose utilization. The effect of BSA was due not to the removal of free fatty acid, but possibly to the binding of long-chain acyl-CoA, resulting in the disinhibition of acetyl-CoA carboxylase and citrate carrier.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1991.tb06370.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Protection of Ischaemic Synaptosomes from Calcium Overload by Addition of Exogenous Lactate (1991)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 57 (1991), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract: In depolarised anoxic synaptosomes, in which lactate production was significantly raised compared with normoxic conditions, calcium uptake, net acetylcholine release, and the intrasynaptosomal calcium concentration were all significantly lowered. In contrast, lactate production in synaptosomes incubated under aglycaemic-and ischaemic-type conditions was significantly lower and basal calcium uptake, acetylcholine release, and intrasynaptosomal calcium concentration were elevated compared with normoxia. In addition, the increase in intrasynaptosomal calcium concentration under the ischaemic-type condition appeared to be greater than could be accounted for by the rise in calcium uptake alone. Intrasynaptosomal pH reflected the lactate production under each condition investigated. Addition of exogenous lactate to normoxic synaptosomes mimicked the effects observed in anoxia, suggesting that lactate itself may have blocked the calcium uptake, inhibiting the rise in intrasynaptosomal calcium and acetylcholine release occurring in depolarised anoxic synaptosomes. When lactate was added to ischaemic synaptosomes, the large rise in intrasynaptosomal calcium concentration, calcium uptake, and acetylcholine release were decreased, suggesting that lactate may have a protective role in preventing cell death by calcium overload under ischaemic-type conditions. Evidence is presented to suggest that the effect of l-lactate was due to the lactate moiety itself rather than the associated acidosis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1991.tb02103.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Development of categorical identification of native and non-native bilabial stops: infants, children and adults (1991)
    Cambridge : Cambridge University Press
    Journal of child language 18 (1991), S. 231-260 
    Details
    ISSN: 0305-0009
    Source: Cambridge Journals Digital Archives
    Topics: Linguistics and Literary Studies
    Notes: Using an infant speech identification (ISI) procedure, English language environment infants, two- and six-year-old children, and adults were tested for their identification of sounds on a native (voiced/voiceless bilabial stop) and a non-native (prevoiced/voiced bilabial stop) speech continuum. Categorical perception of the two contrasts diverged as a function of age, increasing for the native contrast and decreasing for the non-native between two and six years. In Experiment 2, subjects of the same four ages were tested for their identification of a continuum of harmonic tones varying in pitch. Comparison of the results of Experiment i with the essentially continuous perception of this pitch continuum supports the view that the perception of the native contrast becomes more categorical with age, while perception of the non-native contrast becomes less categorical, especially at six years. Experiment 3, in which adults were tested on the three continua with a multi-trial open set procedure, demonstrated that results with the ISI procedure in Experiments 1 and 2 are comparable to results with more traditional methods. The results of the three experiments are discussed in terms of the role of specific linguistic experience in the development of categorical speech perception.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1017/S0305000900011041
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    facet.materialart.
    Unknown
    Swift's VERSES WROTE IN A LADY'S IVORY TABLE-BOOK (1991)
    Washington, etc. : Periodicals Archive Online (PAO)
    Explicator. 49:3 (1991:Spring) 145 
    Details
    ISSN: 0014-4940
    Topics: Linguistics and Literary Studies
    URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pao:&rft_dat=xri:pao:article:1084-1991-049-03-000005
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    facet.materialart.
    Unknown
    Seneca and Ulysses (1991)
    St. Louis : Periodicals Archive Online (PAO)
    The Classical Bulletin. 67:1 (1991) 27 
    Details
    ISSN: 0009-8337
    Topics: Classical Studies
    URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pao:&rft_dat=xri:pao:article:3079-1991-067-01-000004
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    facet.materialart.
    Unknown
    Senecan Drama and Stoic Cosmology (Book Review) (1991)
    St. Louis : Periodicals Archive Online (PAO)
    The Classical Bulletin. 67:2 (1991) 49 
    Details
    ISSN: 0009-8337
    Topics: Classical Studies
    Notes: CLASSICAL BULLETIN BOOK REVIEWS
    URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pao:&rft_dat=xri:pao:article:3079-1991-067-02-000011
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Structure-property relationships in poly(n-vinyl pyrrolidone)-phenoxy-water gels (1991)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 29 (1991), S. 247-259 
    Details
    ISSN: 0887-6266
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Miscible 80/20 and 90/10 by weight blends of poly (n-vinyl pyrrolidone) [PNVP] and phenoxy polymer were swollen with 73-85% water to produce rubbery hydrogels with shear moduli as high as 103dyne/cm2. Small-angle x-ray scattering, rheological, and calorimetric measurements showed that the gel consisted of tie chains, most probably of PNVP embedded in glassy phenoxy particles with radius of gyration 50-200 Å. A ternary phase diagram was calculated assuming athermal mixing between PNVP-H2O and PNVP and the known endothermic interaction between H2O-phenoxy. Phase separation into a phenoxy phase containing minimal H2O and PNVP and a water-swollen PNVP phase was predicted in accordance with experimental results. Phase separation was suspected as forming first an interconnected phenoxy phase which was later dispersed by swelling forces transmitted through PNVP tie chains. The presence of localized internal stress in the swollen network was thought to be responsible for the irreversible decrease in the shear moduli observed at shear strain above 10%.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/polb.1991.090290210
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    A quantitative evaluation of Fourier components in transparent and opaque calf cornea (1991)
    New York, NY [u.a.] : Wiley-Blackwell
    American Journal of Anatomy 191 (1991), S. 408-418 
    Details
    ISSN: 0002-9106
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Fourier transform methods were applied to STEM (scanning transmission electron microscopy) images to detect and quantify the subtle differences between the structure of normal transparent calf cornea and opaque calf cornea. In order for a tissue to be transparent, it can scatter or absorb only a small amount of light. Light scattering is minimized when the principal Fourier components of the spatial fluctuations in the index of refraction have wavelengths which are small relative to the wavelength of light (Benedek, 1971). Corneal opacity was produced as a result of high intraocular pressure (100-150 mmHg) when liquid was injected into calf eyes (0-2 weeks old). Pressurization created large structural defects and slight disruptions in the organization of the collagen fibers. Although the fiber organization appeared similar in the micrographs of both opaque and transparent corneas, Fourier analysis of STEM images collected at 50K magnification identified statistically significant differences. Far fewer Fourier components with wavelengths in the light scattering range (200-1100 nm) were observed in the transparent corneas than in the pressurized corneas as predicted by Benedek's theory. It was of interest that corneas treated with 100% glycerol prior to pressurization remained transparent at high intraocular pressures, possibly because glycerol stabilized the structure of the corneas and maintained a uniform index of refraction across the corneal stroma. The results demonstrate the effectiveness of Fourier analysis in detection and quantification of slight changes in structure at the electron microscopic level.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aja.1001910408
    Library Location Call Number Volume/Issue/Year 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...