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1.
DETECTION OF DNA-PSORALEN PHOTOADDUCTS in situ 总被引:1,自引:0,他引:1
ZOFIA ZAREBSKA† MARIA JARZABEK-CHORZELSKA ‡ GENOWEFA RZSA WIESLAW GLISKI MARIA PAWIKA TADEUSZ CHORZELSKI STEFANIA JABLOKA 《Photochemistry and photobiology》1984,39(3):307-312
Abstract— An immunological method, with the use of specific immune serum, has been developed for detection of 8-methoxypsoralen (8-MOP) photoadducts to DNA, formed in situ in cell nuclei, after combined treatment with 8MOP and UV-A irradiation (Zarçbska et al. , 1978). Lymphocytes fixed on slides or in suspension, and cryostat sections of different mammalian tissues, served as antigenic substrate, after treatment with 8-MOP and UV-A in vitro. Specific fluorescence in these substrates was detected in the nuclei after treatment with 30 ˜ 140 kJ/m2 UV-A in the presence of 0.1-0.3 μg/cm2 8-MOP. PHA-stimulated-lymphocytes appeared to be the most sensitive substrate.
However, hairless mice treated with high doses of UV-A in vivo , 70 ˜ 360 kJ/m2 did not reveal a specific fluorescence of epidermal nuclei, unless a high local concentration of 8-MOP was attained.
The apparent discrepancy in the level of photoadduct detection between the in vitro and in vivo treated specimens was explained by the low number of DNA-8-MOP-photoadducts formed in vivo under these experimental conditions. The relevance of these findings to the role of DNA-8-MOP-photoadducts formed during PUVA photochemotherapy is discussed. 相似文献
However, hairless mice treated with high doses of UV-A in vivo , 70 ˜ 360 kJ/m
The apparent discrepancy in the level of photoadduct detection between the in vitro and in vivo treated specimens was explained by the low number of DNA-8-MOP-photoadducts formed in vivo under these experimental conditions. The relevance of these findings to the role of DNA-8-MOP-photoadducts formed during PUVA photochemotherapy is discussed. 相似文献
2.
The governing equilibrium equations for strain gradient elastic thin shallow shells are derived, considering nonlinear strains and linear constitutive strain gradient elastic relations. Adopting Kirchhoff’s theory of thin shallow structures, the equilibrium equations, along with the boundary conditions, are formulated through a variational procedure. It turns out that new terms are introduced, indicating the importance of the cross-section area in bending of thin plates. Those terms are missing from the existing strain gradient shallow thin shell theories. Those terms highly increase the stiffness of the structures. When the curvature of the shallow shell becomes zero, the governing equilibrium for the plates is derived. 相似文献
3.
Equilibrium of a bar under uniaxial tension is considered as optimization problem of the total potential energy. Uniaxial
deformations are considered for a material with linear constitutive law of strain second gradient elasticity. Applying tension
on an elastic bar, necking is shown up in high strains. That means the axial strain forms two homogeneously deformed sections
in the ends of the bars and a section in the middle with high variable strain. The interactions of the intrinsic (material)
lengths with the non linear strain displacement relations develop critical states of bifurcation with continuous Fourier’s
spectrum. Critical conditions and post-critical deformations are defined with the help of multiple scales perturbation method.
An erratum to this article can be found at 相似文献
4.
The present work introduces fractional calculus into the continuum mechanics area describing non-local constitutive relations. Considering a one-dimensional body and assuming total stored energy depending not only upon the local strain but also upon a fractional derivative of the stain, an elastic model with non-local stress–strain behavior is introduced. Fractional calculus provides a natural framework for describing non-local constitutive relations and requires no assumptions for the interval of non-local influence. Furthermore, the proposed method works in finite intervals contrary to the existing theories requiring infinite domains. 相似文献
5.
P.D. Draggiotis R.H.P. Kleiss A. Lazopoulos C.G. Papadopoulos 《The European Physical Journal C - Particles and Fields》2006,46(3):741-750
We present a proof of the Britto–Cachazo–Feng–Witten tree-level recursion relation for gluon amplitudes in QCD, based on a
direct equivalence between BCFW decompositions and Feynman diagrams. We demonstrate that this equivalence can be made explicit
when working in a convenient gauge. We exhibit that gauge invariance and the particular structure of Yang–Mills vertices guarantee
the validity of the BCFW construction. 相似文献
6.
ABSTRACT. Let G be the group ?[t, t ?1] x ?. By studying the action of the braid group Bn on the set Gn , we obtain representations of Bn into a wreath product of the symmetric group and the general linear group over ?[t, t ?1]. This in particular recovers the Burau representation of the braid group. Furthermore, some quotients of the braid group are obtained by using the representations found. 相似文献
7.
The study of viscous flow in tubes with deformable walls is of specific interest in industry and biomedical technology and
in understanding various phenomena in medicine and biology (atherosclerosis, artery replacement by a graft, etc) as well.
The present work describes numerically the behavior of a viscous incompressible fluid through a tube with a non-linear elastic
membrane insertion. The membrane insertion in the solid tube is composed by non-linear elastic material, following Fung’s
(Biomechanics: mechanical properties of living tissue, 2nd edn. Springer, New York, 1993) type strain–energy density function.
The fluid is described through a Navier–Stokes code coupled with a system of non linear equations, governing the interaction
with the membrane deformation. The objective of this work is the study of the deformation of a non-linear elastic membrane
insertion interacting with the fluid flow. The case of the linear elastic material of the membrane is also considered. These
two cases are compared and the results are evaluated. The advantages of considering membrane nonlinear elastic material are
well established. Finally, the case of an axisymmetric elastic tube with variable stiffness along the tube and membrane sections
is studied, trying to substitute the solid tube with a membrane of high stiffness, exhibiting more realistic response. 相似文献
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10.
K. A. Lazopoulos 《Archive of Applied Mechanics (Ingenieur Archiv)》1991,61(4):215-221
Summary The buckling problem of a cantilever column is discussed when the axial loading device introduces friction forces. Adopting global stability criteria and applying the bifurcation theory to the present non-conservative eigenvalue problem, the critical load is defined and the post-critical behavior is investigated.
Stabknickung unter Reibungseinfluß
Übersicht Die Ausknickung einer eingespannten Säule wird diskutiert, wobei durch die axiale Belastungsvorrichtung Reibungskräfte aufgebracht werden. Unter der Annahme eines globalen Stabilitätskriteriums und der Verwendung der Verzweigungstheorie wird die kritische Last des Systems und sein nachkritisches Verhalten untersucht.相似文献