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
  • Core-fibrils  (2)
  • X-ray analysis  (2)
  • nucleation  (2)
  • Activation  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Expression of CD69 on T-cells from HIV-1-infected children and adolescents increases with increasing viral load (1999)
    Springer
    European journal of pediatrics 158 (1999), S. 638-644 
    Details
    ISSN: 1432-1076
    Keywords: Key words HIV-1 ; T-cells ; CD69 ; Activation ; Children
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We evaluated the use of a whole-blood assay that measures spontaneous and activation-induced CD69 expression on peripheral blood T-cells in vitro for assessment of T-cell function in HIV-1-infected paediatric patients. Heparinized venous blood from 28 HIV-1 positive children and adolescents and 23 healthy controls was incubated for 4 h with or without 5 μg/ml phytohaemagglutinin (PHA). Thereafter, analysis of CD69 expression on CD4+ and CD8+ T-cells was done by flow cytometry; simultaneously we determined CD4+ T-cell counts and plasma HIV-1 viral load. Neither spontaneous nor PHA-induced CD69 expression differed significantly between HIV-1 positive patients and healthy controls. However, T-cells from HIV-1 positive patients with plasma HIV-1 viral load levels above 70 × 103 copies/ml showed a higher spontaneous CD69 expression than T-cells from patients with lower plasma viral load levels in different stages of the disease. Antiretroviral treatment in four patients reduced spontaneous CD69 expression in CD4+ T-cells and PHA-induced CD69 expression in CD4+ and CD8+ T-cells significantly after 8 weeks of therapy. Conclusion Spontaneous and activation-induced expression of the early (activation) antigen CD69 on peripheral blood T-cells does not distinguish HIV-1 positive patients from HIV-1 negative healthy controls and is not correlated with peripheral blood CD4+ T-cell counts. This test may not be a reliable marker for functional T-cell deficiency during early stages of HIV disease. Increased spontaneous as well as PHA-induced CD69 expression on T-cells from HIV-1-infected children and adolescents in vitro may rather reflect HIV-induced pre-activation of T-cells in vivo.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004310051167
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Crystallization kinetics of isotactic polypropylene blended with atactic polystyrene (1990)
    Springer
    Colloid & polymer science 268 (1990), S. 528-535 
    Details
    ISSN: 1435-1536
    Keywords: Polypropylene/polystyreneblends ; nucleation ; isothermalcrystallization ; spheruliticgrowth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Crystallization kinetic parameters, such as spherulitic growth rates, nucleation densities, and Avrami-exponents, have been determined by optical microscopy for isotactic polypropylene blended with atactic polystyrene. It is found that the crystallization of iPP is strongly influenced by the presence of polystyrene. With increasing PS concentration in the blend, the nucleation densities decrease, while the spherulitic growth rates as well as the positions of thermal peaks, measured by DSC, remain independent of sample composition. Due to the formation of interfaces as a consequence of increasing dispersion of polystyrene the nucleation changes from preferentially thermal to athermal.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01410294
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    The microstructure of trans-polyoctenamer (1988)
    Springer
    Colloid & polymer science 266 (1988), S. 227-234 
    Details
    ISSN: 1435-1536
    Keywords: Polyoctenamer ; microstructure ; X-ray analysis ; electron microscopy ; interface distribution function
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The microstructure of trans-polyoctenamer has been investigated as a function of the trans double bond concentration and the type of regulator. The samples were characterized using GPC, DSC and X-ray wide and small angle scattering. The small angle scattering was analyzed by calculating interface distribution functions and by Guinier and Porod analysis. It was found that the microstructure is primarily determined by the trans content. The type of regulator has a minor influence.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01452584
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    X-ray investigations of the formation of core-fibrils crystallized out of the oriented melt (1988)
    Springer
    Colloid & polymer science 266 (1988), S. 411-418 
    Details
    ISSN: 1435-1536
    Keywords: Core-fibrils ; crystallization models ; fiber morphology ; X-ray analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Crystallization models for the formation of core-fibrils crystallized from the oriented melt are discussed by comparing results from X-ray experiments with theoretical predictions. Two sets of polymer blends, the systems iPP/PB-1 and iPP/aPP have been measured. From wide angle X-ray scattering, the thicknesses of the core-fibrils, lattice distortions, and unit-cell parameters have been determined. Interface distribution functions have been used to evaluate the axial morphology of the fibers from meridional small angle X-ray scattering curves. It appears that the morphological predictions made by the crystallization models of Pennings and of Hoffman cannot be confirmed by the experimental findings. The diffusion model proposed by Petermann partially describes the morphological properties of the core-fibrils.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01457257
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Investigation of axial density modulations of core fibrils by interface distribution functions (1986)
    Springer
    Colloid & polymer science 264 (1986), S. 1017-1023 
    Details
    ISSN: 1435-1536
    Keywords: Core-fibrils ; axial density — modulation ; interface distribution functions ; defect clustering
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The axial density modulation of core-fibrils in polypropylene and poly (1butene) crystallized from the oriented melt has been investigated by calculating interface distribution functions of the small angle x-ray scattering. The density modulation along the fiber axis originates from the migration of chain defects in the early stages of crystallization in the shear-field. The lengths of the needle crystals are approximately three times higher than those of the distorted zones. The values of the interface lengths between crystals and zones of lower electron density, are matching well with the lengths of the distorted zones. This result confirms the concept of defect clustering.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01410319
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Molecular fractionation in isotactic polypropylene during isothermal crystallization (1998)
    Springer
    Colloid & polymer science 276 (1998), S. 747-749 
    Details
    ISSN: 1435-1536
    Keywords: Key words Polypropylene ; nucleation ; isothermal crystallization ; molecular fractionation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The nucleation frequency of isotactic polypropylene shows for certain molecular weight distributions during isothermal crystallization a “stepwise” development of the nuclei as a function of time. The resulting curve can be fitted by a superposition of exponential functions assuming a separate nucleation density for each nucleation step. The multimodal nucleation is discussed as a consequence of molecular fractionation effects during crystallization.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003960050013
    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...