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排序方式: 共有177条查询结果,搜索用时 15 毫秒
1.
V V Cherny M Paulitschke M V Simonova E Hessel V S Ermakov YuASokolov D Lerche V S Markin 《General physiology and biophysics》1989,8(1):23-37
The action of the antiviral drug rimantadine on the structure of bilayer lipid membranes (BLM) and RBC membranes was investigated. Structural changes in BLM were recorded by ionophore conductivity changes and by changes in the third harmonic of capacity current signal due to lateral compression of BLM in an electric field. It was shown that the adsorption of rimantadine on BLM results in an increase in ionophore mobility in bilayer membranes of dioleolyllecithin (DOL) and common lipids of bovine brain (CL) and in a decrease in those of azolectin (A). Relative changes in the third harmonic signal also depend on the membrane composition and have different signs. The results may be explained by the rimantadine action on the lipid bilayer structure: "rigidification" of A-membranes and "fluidization" of BLM from DOL and CL. Structural reorganization of RBC membranes as investigated by the ability of the cells to enter a micropipette (inner diameter greater than or equal to 3 microns) thereby undergoing deformation. It was shown that rimantadine influences RBC deformability due to drug induced inhomogenous mechanical membrane properties. Also, rimantadine accelerated the process of artificially induced aggregation of erythrocytes. The relation of the effects on artificial and biological membranes, and the structural changes in the lipid phase of membrane are discussed. 相似文献
2.
The separation process of blood and RBC suspensions in a hematocrit range between 0.3-0.7 was investigated with a centrifuge allowed to run at low accelerations (100 xg-1000 xg). The position of the interface between the supernatant of plasma and the RBC column was continuously recorded by a new optoelectronic measuring system. The separation process could be mathematically described by an exponential decrease of the cell column approaching a final packing. At a given centrifugal acceleration the time constant is influenced by hematocrit, aggregation, deformation and plasma viscosity. The final packing depends linearly on the starting hematocrit (0.3-0.7) and can be used as a measure of deformability. 相似文献
3.
Hardies SC; Martin SL; Voliva CF; Hutchison CA d; Edgell MH 《Molecular biology and evolution》1986,3(2):109-125
4.
A major difference between the divergence patterns within the lines-1 families in mice and voles 总被引:3,自引:0,他引:3
Vanlerberghe F; Bonhomme F; Hutchison CA d; Edgell MH 《Molecular biology and evolution》1993,10(4):719-731
L1 retroposons are represented in mice by subfamilies of interspersed
sequences of varied abundance. Previous analyses have indicated that
subfamilies are generated by duplicative transposition of a small number of
members of the L1 family, the progeny of which then become a major
component of the murine L1 population, and are not due to any active
processes generating homology within preexisting groups of elements in a
particular species. In mice, more than a third of the L1 elements belong to
a clade that became active approximately 5 Mya and whose elements are >
or = 95% identical. We have collected sequence information from 13 L1
elements isolated from two species of voles (Rodentia: Microtinae: Microtus
and Arvicola) and have found that divergence within the vole L1 population
is quite different from that in mice, in that there is no abundant
subfamily of homologous elements. Individual L1 elements from voles are
very divergent from one another and belong to a clade that began a period
of elevated duplicative transposition approximately 13 Mya. Sequence
analyses of portions of these divergent L1 elements (approximately 250 bp
each) gave no evidence for concerted evolution having acted on the vole L1
elements since the split of the two vole lineages approximately 3.5 Mya;
that is, the observed interspecific divergence (6.7%-24.7%) is not larger
than the intraspecific divergence (7.9%-27.2%), and phylogenetic analyses
showed no clustering into Arvicola and Microtus clades.
相似文献
5.
Human aminopeptidase N is encoded by 20 exons 总被引:1,自引:0,他引:1
6.
D Lerche 《Biorheology》1984,21(4):477-492
On the basis of a recently developed biophysical model of cell-cell interaction, including electrostatic, electrodynamic, steric and bonding/bridging interaction energies the influence of different fixed charge (dissociated groups of the glycocalyx) density distributions in red blood cell (RBC) glycocalyces on the total free interaction energy was investigated. An analytical equation of electrostatic free energy on the basis of the linear Poisson-Boltzmann approach taking into account arbitrary distributions of fixed glycocalyx charges was obtained and corresponding free electrostatic energies of three example distributions were calculated. The electrodynamic, steric and bonding/bridging energies were computed as usual. It was shown that the free energy as a function of interaction distances strongly depends on the charge distribution and, correspondingly, the "weight" of this energy term in the total free interaction energy balance equation. Generally, it can be stated that as more charges are assumed to be fixed in the outer layer of RBC glycocalyx as more important becomes the electrostatic energy in contrast to the remaining three terms. 相似文献
7.
By electron microscopic visualisation of totally denatured DNA, we have detected photochemically induced 8-methoxypsoralen crosslinks in vitro after irradiation at 360 nm. The amount of crosslinks was expressed as the percentage of DNA length which was kept in double-stranded appearance by closely situated crosslinks. This percentage correlated well with irradiation time, irradiation intensity, and the concentration of 8-methoxypsoralen. These parameters have also been correlated with the mean size and the size distribution of non-crosslinked regions of DNA, so called bubbles. For a comparison with another psoralen type, we have carried out a similar set of experiments using 4,5,8-trimethylpsoralen. 相似文献
8.
9.
Oylum Erkus Victor CL de Jager Maciej Spus Ingrid J van Alen-Boerrigter Irma MH van Rijswijck Lucie Hazelwood Patrick WM Janssen Sacha AFT van Hijum Michiel Kleerebezem Eddy J Smid 《The ISME journal》2013,7(11):2126-2136
Maintenance of a high degree of biodiversity in homogeneous environments is poorly understood. A complex cheese starter culture with a long history of use was characterized as a model system to study simple microbial communities. Eight distinct genetic lineages were identified, encompassing two species: Lactococcus lactis and Leuconostoc mesenteroides. The genetic lineages were found to be collections of strains with variable plasmid content and phage sensitivities. Kill-the-winner hypothesis explaining the suppression of the fittest strains by density-dependent phage predation was operational at the strain level. This prevents the eradication of entire genetic lineages from the community during propagation regimes (back-slopping), stabilizing the genetic heterogeneity in the starter culture against environmental uncertainty. 相似文献
10.
Irisin was first identified in muscle cells. We detected irisin immunoreactivity in various organs of the crested porcupine (Hystrix cristata). In the epidermis, irisin immunoreactivity was localized mainly in stratum basale, stratum spinosum and stratum granulosum layers; immunoreactivity was not observed in the stratum corneum. In the dermis, irisin was found in the external and internal root sheath, cortex and medulla of hair follicles, and in sebaceous glands. Irisin immunoreactivity was found in the neural retina and skeletal muscle fibers associated with the eye. The pineal and thyroid glands also exhibited irisin immunoreactivity. 相似文献