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1.
Haplotype analysis of the human apolipoprotein B mutation associated with familial defective apolipoprotein B100. 总被引:8,自引:2,他引:6 下载免费PDF全文
Haplotype analysis was conducted on the mutant allele of 14 unrelated subjects heterozygous for a mutation in the codon for amino acid 3500 of human apolipoprotein B100. This mutation is associated with defective binding of low-density lipoprotein to the low-density lipoprotein receptor and with moderate hypercholesterolemia. Ten markers were used for haplotyping: eight diallelic markers within the structural gene and two hypervariable loci flanking the gene. Seven of eight unequivocally deduced haplotypes were identical, and one revealed only a minor difference at one of the hypervariable loci. The genotypes of the six other affected subjects were consistent with this same assigned haplotype. These data are consistent with a common ancestral chromosome and provide no evidence for a recurrent mutation at this potentially hypermutable CG dinucleotide, despite the fact that this mutation is not rare. 相似文献
2.
Ludwig v. Farkas-Vukotinovic 《Plant Systematics and Evolution》1858,8(2):66-67
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3.
Ludwig Vágner 《Plant Systematics and Evolution》1857,7(3):22-23
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4.
H Kühn U Salzmann-Reinhardt P Ludwig K P?nicke T Schewe S Rapoport 《Biochimica et biophysica acta》1986,876(2):187-193
Simultaneous measurements of oxygen uptake and conjugated diene formation (increase in the absorbance at 234 nm) during the dioxygenation of linoleic acid by the pure reticulocyte lipoxygenase gave a nearly theoretical stoichiometry of 1.1 in a temperature range from 5 to 30 degrees C and a wide range of concentrations of both oxygen and linoleic acid. At low concentrations of either oxygen or linoleic acid or both, secondary processes occurred such as linoleic acid-supported lipohydroperoxidase reactions leading to the disappearance of conjugated dienes and to the formation of oxodienes, linoleic acid dimers and epoxyhydroxy derivatives. Under these conditions marked deviations of the stoichiometry between oxygen uptake and conjugated diene formation appeared. The formation of conjugated oxodienoic fatty acids absorbing at 285 nm occurred only under conditions of high concentrations of linoleic acid and limiting oxygen supply. The results indicate that lipohydroperoxidase reactions catalyzed by the pure reticulocyte lipoxygenase do not only take place under strictly anaerobic conditions but also under conditions of limiting concentrations of either linoleic acid or oxygen or both. 相似文献
5.
Bioprocess and Biosystems Engineering - Polymersomes are hollow, spherical vesicles that are surrounded by a polymer membrane. The applied polymer must be amphiphilic to promote self-assembly in... 相似文献
6.
7.
Dr. Ludwig Lämmermayr 《Plant Systematics and Evolution》1910,60(4):129-132
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9.
R Ladenstein B Meyer R Huber H Labischinski K Bartels H D Bartunik L Bachmann H C Ludwig A Bacher 《Journal of molecular biology》1986,187(1):87-100
Heavy riboflavin synthase from Bacillus subtilis is an enzyme complex consisting of approximately three alpha-subunits (Mr 23.5 X 10(3)) and 60 beta-subunits (Mr 16 X 10(3)). The enzyme has been crystallized from phosphate buffer in a hexagonal crystal modification that belongs to space group P6(3)22. The asymmetric unit of the crystal cell contains ten beta-subunits. The structure of this unusual 10(6) Mr protein has been studied by small-angle X-ray scattering, electron microscopy of three-dimensional crystals, and crystallographic methods. The scattering curves can be interpreted in terms of a hollow sphere model with a ratio of inner and outer radius of 0.3:1. A diameter of 168 A was estimated from the scattering curves, in close agreement with electron microscopic studies. An aggregate with the stoichiometry beta 60, which was obtained by ligand-driven reaggregation of isolated beta-subunits, showed similar shape and dimensions, but a larger value for the ratio Ri/Ra. Electron micrographs of freeze-etched enzyme crystals showed approximately spherical molecules, which were arranged in hexagonal layers. The lattice constants found from the micrographs are in good agreement with the values derived from X-ray diffraction data. Rotation function calculations in Patterson space showed a set of peaks for 2-fold, 3-fold and 5-fold local rotation axes, accurately consistent with icosahedral symmetry and with the particle orientation A shown in the Appendix. The crystal packing can be described as follows: enzyme particles with icosahedral symmetry (point group 532) are located at points 32 of the hexagonal cell, corresponding to positions (0, 0, 0) and (0, 0, 1/2) on the 6-fold screw axes. From the data reported, it may be concluded that the enzyme structure can be described as an icosahedral capsid of 60 beta-subunits with the triangulation number T = 1. The alpha-subunits are located in the central core space of the capsid, but their spatial orientation is incompletely understood. 相似文献
10.
R. Gottlieb G. A. Lienert O. Ludwig K. Rockenfeller 《Biometrical journal. Biometrische Zeitschrift》1984,26(4):351-381
Tables for Bonferroni-adjusted significance levels of Student's t are provided for r = 3(1)30(5)50 etc. and alphas of 0.05, 0.01 and 0.001. The tables are suggested for various applications, for example in replacing analysis of variance of k samples by r simultaneous t tests. Use of the tables is shown by numerical examples. The adjustment of alpha for improving the efficiency of testing is made by WILKINSON for orthogonal comparisons and by HOLM for nonorthogonal comparisons. 相似文献