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991.
Lone B Madsen Bo Thomsen Knud Larsen Christian Bendixen Ida E Holm Merete Fredholm Arne L Jørgensen Anders L Nielsen 《BMC neuroscience》2007,8(1):72
Background
The transmembrane presenilin (PSEN) proteins, PSEN1 and PSEN2, have been proposed to be the catalytic components of the γ-secretase protein complex, which is an intramembranous multimeric protease involved in development, cell regulatory processes, and neurodegeneration in Alzheimer's disease. Here we describe the sequencing, chromosomal mapping, and polymorphism analysis of PSEN1 and PSEN2 in the domestic pig (Sus scrofa domesticus). 相似文献992.
Dendritic cells (DCs) are potent antigen-presenting cells and critical for the priming of CD8+ T cells. Therefore the use
of these cells as adjuvant cells has been tested in a large number of experimental and clinical vaccination studies, in particular
cancer vaccine studies. A number of protocols are emerging that combine vaccination with CTL expanding strategies, such as
e.g. blockade of CTLA-4 signalling. On the other hand, the lifespan and in vivo survival of therapeutic DCs have only been addressed in a few studies, although this is of importance for the kinetics of
CTL induction during vaccination. We have previously reported that DCs loaded with specific antigens are eliminated by antigen
specific CTLs in vivo and that this elimination affects the potential for in vivo CTL generation. We now show that CTLA-4 blockade increases the number of DC vaccine induced LCMV gp33 specific CTLs and the
lysis of relevant in vivo targets. However, the CTLA-4 blockage dependent expansion of CTLs also affect DC survival during booster DC injections and
our data suggest that during a booster DC vaccine, the largest increase in CTL levels is already obtained during the first
vaccination. 相似文献
993.
Anders Melin 《Arkiv f?r Matematik》1971,9(1-2):117-140
994.
A detailed comparison of the simplex method for linear programming with a recent interval linear programming algorithm reveals that the methods are identical in the sense that the same sequence of extreme points can be generated by either algorithm. 相似文献
995.
996.
A linear scaling method for calculation of the static ab initio response within self-consistent field theory is developed and applied to the calculation of the static electric polarizability. The method is based on the density matrix perturbation theory [Phys. Rev. Lett. 92, 193001 (2004)]], obtaining response functions directly via a perturbative approach to spectral projection. The accuracy and efficiency of the linear scaling method is demonstrated for a series of three-dimensional water clusters at the RHF/6-31G(**) level of theory. The locality of the response under a global electric field perturbation is numerically demonstrated by the approximate exponential decay of derivative density matrix elements. 相似文献
997.
Laminar optical tomography: demonstration of millimeter-scale depth-resolved imaging in turbid media
Laminar optical tomography (LOT) is a new technique that combines the advantages of diffuse optical tomography image reconstruction and a microscopy-based setup to allow noncontact imaging with 100-200-microm resolution effective over depths of 0-2.5 mm. LOT is being developed primarily for multispectral imaging of rat cortex, for which resolving functional dynamics in various layers of the brain's cortex (to depths of 1500 microm) is of increasing interest to neurophysiologists. System design and image reconstruction techniques are described, along with simulation and phantom results that demonstrate the characteristics and limitations of system accuracy and resolution. 相似文献
998.
Nielsen AB Hvelplund P Liu B Nielsen SB Tomita S 《Journal of the American Chemical Society》2003,125(32):9592-9593
Electron capture to monoanionic metal complexes in high-energy collisions with sodium vapor is shown to occur with the formation of dianions. In this way, we prepared the small dianions Cr(SCN)42-, Fe(CN)42-, Pt(NO2)22-, and Pt(C2O4)22- in the gas phase. The Cr(SCN)42- dianion Coulomb explodes into Cr(SCN)3- and SCN- with a release of kinetic energy (3.2 +/- 0.4 eV) into translational energy of the fragments. The scheme provides a way to study charge dissociation reactions of molecular dianions that are too short-lived to survive extraction from the ion source. 相似文献
999.
Thomas L Luning J Scholl A Nolting F Anders S Stohr J Parkin SS 《Physical review letters》2000,84(15):3462-3465
The demagnetization of a hard ferromagnetic layer via the fringing fields of domain walls created by reversing the moment of a neighboring soft ferromagnetic layer is explored experimentally. An unusual oscillatory decay of the magnetic moment of the hard layer is observed using structures in which the demagnetization occurs after a few hundred cycles. This surprising observation is confirmed on a microscopic scale by detailed imaging of the magnetization of the hard layer using high resolution photoemission electron microscopy and by micromagnetic simulations. 相似文献
1000.
In this paper we will consider scattering of elastic waves in a half space. The half space is an isotropic, linear and homogeneous medium except for a finite inhomogeneity. The T-matrix method (also called the “extended boundary condition method” or “null field approach”) is extended to derive expressions for the elastic field inside the half space and the surface field on the interface. The assumptions on the source that excites the half space are fairly weak. In the numerical applications found in this paper we assume a Rayleigh surface wave to be the incoming field, and we only compute the surface displacements. We make illustrations on some simple types of scatterers (spheres and spheroids; the latter ones can be arbitrarily oriented). 相似文献