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891.
892.
H. Mussauer V.L. Sukhorukov A. Haase U. Zimmermann 《The Journal of membrane biology》1999,170(2):121-133
The interaction of human red blood cells (RBCs) with diethylenetriamine-pentaacetic acid (DTPA) or its Gd-complex (Magnevist,
a widely used clinical magnetic resonance contrast agent containing free DTPA ligands) led to the following, obviously interrelated
phenomena. (i) Both compounds protected erythrocytes against electrohemolysis in isotonic solutions caused by a high-intensity
DC electric field pulse. (ii) The inhibition of electrohemolysis was observed only when cells were electropulsed in low-conductivity
solutions. (iii) The uptake of Gd-DTPA by electropulsed RBCs was relatively low. (iv) (Gd-) DTPA reduced markedly deformability
of erythrocytes, as revealed by the electrodeformation experiments using high-frequency electric fields. Taken together, the
results indicate that (Gd-) DTPA produce stiffer erythrocytes that are more resistant to electric field exposure. The observed
effects of the chelating agents on the mechanical properties and the electropermeabilization of RBCs must have an origin in
molecular changes of the bilayer or membrane-coupled cytoskeleton, which, in turn, appear to result from an alteration of
the ionic equilibrium (e.g., Ca2+ sequestration) in the vicinity of the cell membrane.
Received: 19 January 1999/Revised: 1 April 1999 相似文献
893.
Spontaneous non-antigen-dependent cytotoxicity is displayed in vitro by mononuclear cells from molluscs, annelids, and echinoderms. The cytotoxic potential of these cells appears to be independent of prior antigenic exposure, is easily demonstrated in vitro, and is temperature dependent. The specificity of these cells may be directed at cell-surface glycoproteins on the target cell surface since a variety of defined mono- and disaccharides can block killing. The ability of sugars to block is target cell and effector cell specific. This finding is exactly analogous to our previous finding that human spontaneous monocyte-mediated cytotoxicity is blocked in a target-specific fashion by different mono- and disaccharides. These data suggest that invertebrate as well as vertebrate mononuclear cells may “recognize” targets through a series of sugar-specific “lectin-like” molecules present on the effector cell surface. 相似文献
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896.
Summary Two siblings with a short-limb dwarfing condition which we call acromesomelic dysplasia, Hunter-Thompson type are reported. Abnormalities are limited to the limbs and limb joints in this severe form of dwarfism. The middle and distal
segments of the limbs are most affected. The lower limbs are more affected than the upper. We are aware of one previously
published case of this entity reported by A. G. W. Hunter and M. W. Thompson in 1976. Dislocations of the elbows and ankles
were present in all three patients and dislocations of the hips and knees in two. One of the siblings who did not have hip
and knee dislocations clinically resembled Grebe chondrodysplasia, another severe acromesomelic dwarfing condition. However,
radiological analysis suggests that while acromesomelic dysplasia, Hunter-Thompson type and Grebe chondrodysplasia are related,
they are not identical. Grebe chondrodysplasia has been established as an autosomal recessive trait. It appears probable that
the entity we describe has the same mode of genetic transmission. 相似文献
897.
Interaction of Legionella pneumophila with tissue culture cells 总被引:1,自引:0,他引:1
898.
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