Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    ISSN: 1432-0959
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract This paper presents a formulation of continuum theory for nematic liquid crystals based upon the balance laws for linear and angular momentum, that derives directly expressions for stress and couple stress in these transversely isotropic liquids. This approach therefore avoids the introduction of generalised forces or torques associated with the director describing the axis of transverse isotropy.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-1106
    Keywords: Cholecystokinin ; Immunocytochemistry ; Neuropeptides ; Cerebral cortex ; Local circuit neurons
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Cholecystokinin (CCK)-like immunoreactive neurons have been reported to be widely distributed throughout both the neo- and allocortices. In the present study, we were interested in determining whether these cortical CCK neurons have long projections using the double-labeling technique of fluorescence retrograde tracing combined with immunofluorescence for CCK. The distribution of CCK immunoreactive perikarya and fibers was plotted throughout the rostro-caudal extent of the cerebral cortex in both untreated and colchicine-treated albino rats. In the double-labeling experiments, the animals received injections of fluorescent retrograde tracers into cortical, limbic, striatal or thalamic structures, followed one to two days later by colchicine treatment. Brains were subsequently processed for indirect immunofluorescence for CCK-octapeptide and fluorescent dye localization. It was found that 1) a small number of prefrontal cortical CCK neurons were double-labeled with both fluorescent dye and immunofluorescence for CCK after dye injection into midline thalamus, 2) only rarely were cortical CCK neurons double-labeled with injection of tracers into cortex, striatum, or other subcortical structures, 3) numerous midbrain CCK neurons were double-labeled after dye injection into prefrontal cortex and anterior cingulate cortex. and 4) colchicine or cannula injection damage to cortical forebrain tracts (corpus callosum, internal capsule, external capsule, anterior commissure) resulted in the appearance of numerous CCK immunoreactive fibers not normally seen in the undamaged tracts. Although the possibility remains that cortical CCK neurons may be refractory to transport of retrograde tracers, these results suggest that CCK-like immunoreactive neurons of the rat cerebral cortex are predominantly local circuit neurons and that only minor corticocortical and cortico-subcortical CCK-containing projections exist.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-0673
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Physics
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Presynaptic modulation of synaptic transmission is the primary function of central nicotinic acetylcholine receptors (nAChRs) in developing and adult brain. nAChR activation regulates release of various neurotransmitters, including norepinephrine (NA). Given evidence that NA may serve a critical functional role in cerebellar development, we have undertaken studies to determine whether nAChRs modulate NA release in developing cerebellum. In vitro experiments using cerebellar slices examined the effects of nAChR stimulation on release of radiolabeled NA ([3H]NA). Our data indicate the presence of functional nAChRs on NA terminals in immature cerebellum and subsequent developmental regulation of receptor properties. During postnatal week one, the maximally effective dose of nicotine released 35.0 ± 1.2% of cerebellar [3H]NA stores. There was a subsequent decline in maximal nicotine-stimulated NA release until postnatal day 30, when Emax values were statistically indistinguishable from adult. Although the efficacy of nicotine changed substantially throughout development, EC50 values did not differ significantly (EC50 = 4.4–12.0 µm). Pharmacological analysis indicated that this developmental shift in maximum nicotine effect reflects a change in the properties of the nAChRs. These data support recent findings of a possible functional role of nAChRs in regulating cerebellar ontogeny, and provides further support for the role of NA as a neurotrophic factor during development.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1432-0959
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract This article describes the relationships between the alternative formulations of the bulk non-chiral smectic C liquid crystal energies currently available in the literature; the relative equivalence of these energies is discussed and demonstrated.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    ISSN: 1432-0673
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Physics
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    ISSN: 1432-0673
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Physics
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1420-9039
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Physics
    Description / Table of Contents: Résumé Cet article utilise des arguments de l'invariance pour poser une équation mettant en rapport la densité de l'énergie cinétique et les densités de la vitesse linéaire et angulaire dans le continuum de Cosserat. Bien que ce rapport puisse être utile pour déterminer une densité, les autres étant données, un tel approche souffre généralement d'un manque de spécificité. En particulier il est clair que certaines des propositions précédentes concernant la densité de la vitesse angulaire ne résultant pas uniquement de l'équation posée, bien qu'elles satisfassent les exigences de l'invariance. Par conséquent la valeur de la relation repose sur son utilisation comme un test de consistance sur des formes donneés pour les différentes densités. Des exemples de cas particuliers d'interêt pratique sont donnés afin d'illustrer de telles applications.
    Notes: Abstract This paper employs invariance arguments to derive an equation relating the kinetic energy density to the densities of linear and angular momentum in a Cosserat continuum. While this relationship may serve to determine one density given the others, such an approach in general suffers from a lack of uniqueness. In particular, it is shown that certain previous proposals for the angular momentum density do not follow uniquely from the derived equation, although they do satisfy invariance requirements. Consequently, the value of the relationship lies in its use as a consistency test upon proposed forms for the different densities. Examples are given for special cases of practical interest which illustrate such applications.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 34 (1980), S. 0 
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1365-2826
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Early neonatal handling of rat pups produces dampened hypothalamic-pituitary-adrenal axis reactivity to stress in adult male offspring. However, less is known about whether there is a similar effect for females. Although, most studies of neonatal handling have examined subsequent effects during adulthood, adolescence is an important developmental stage for stress responsivity. To address these issues, the effect of neonatal handling on the endocrine stress response and brain activity of male and female rats was determined in response to acute restraint stress during adolescence. Consistent with previous findings in adult males, neonatal handling reduced restraint stress-induced hormone levels in adolescent males. However, in contrast, we found elevated plasma hormone concentrations in handled females. A gender-specific handling effect on brain activity was also evident, with significantly increased stress-induced activation of the posterior cingulate cortex of handled females, as measured by c-fos mRNA expression. The striking gender difference in the effect of early neonatal handling provides evidence that this must be considered as an important variable in subsequent stress responsivity induced by early manipulations.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...