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991.
Khakass families can be considered as a fundamental ethnic determinant. Based on the family subdivision the analysis of intensity and genetic effectiveness of marriage migrations has revealed the speed of formation of a new ethnic-territorial community--Khakass nationality--on the territory of the Minusinsk hollow. 相似文献
992.
Ralf J. Jäger Vincent R. Harley Rudolf A. Pfeiffer Peter N. Goodfellow Gerd Scherer 《Human genetics》1992,90(4):350-355
A familial mutation in SRY, the gene coding for the testis-determining factor TDF, was identified in an XY female with gonadal dysgenesis, her father, her two brothers and her uncle. The mutation consists of a T to C transition in the region of the SRY gene coding for a protein motif known as the high mobility group (HMG) box, a protein domain known to confer DNA-binding specificity on the SRY protein. This point mutation results in the substitution, at amino acid position 109, of a serine residue for phenylalanine, a conserved aromatic residue in almost all HMG box motifs known. This F109S mutation was not found in 176 male controls. When recombinant wildtype SRY and SRYF109S mutant protein were tested in vitro for binding to the target site AAC AAAG, no differences in DNA-binding activity were observed. These results imply that the F109S mutation either is a rare neutral sequence variant, or produces an SRY protein with slightly altered in vivo activity, the resulting sex phenotype depending on the genetic back-ground or environmental factors.This paper is dedicated by G. S. to Professor Ulrich Wolf on the occasion of his 60th birthday 相似文献
993.
V. G. Grigoryan A. R. Aghababyan A. N. Arakelyan A. Yu. Stepanyan 《Human physiology》2006,32(4):489-491
A comparative analysis of the time and amplitude characteristics of the negative N200 and positive P300 components of visual evoked potentials recorded at symmetric points of the frontal, parietal, temporal, and occipital areas of the right and left hemispheres of the cerebral cortex has been performed in subjects with or without the skill of operating a computer. Subjects inexperienced in an operator’s work exhibited an interhemispheric difference in the time and amplitude characteristics of the studied components. In subjects that had the skill of operating a computer, the interhemispheric difference was little, which suggests that the cortex plays only a small role in the cerebral control of this activity. 相似文献
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V. A. KRASSILOV E. V. BUGDAEVA 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1988,21(4):425-431
Meeusella gen. nov. is a strobilate pollen organ from the Lower Cretaceous of Transbaikalie (east of the Lake Baikal); the branched lateral branches (paracladia), if fully developed, bear a subterminal pair of stalked synangial heads. In some cases the latter are reduced to a pair of sessile heads or the paracladia are sterile. It is suggested that the synangial heads might be further reduced to a pair of bisporangiate thecae, while the paracladium apex between them might form a prominent connective of a typical stamen. ▭ Androecium, androclade, angiosperms, proangiesperms, stamen, evolutionary morphology. 相似文献
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Hydrogen bonding in globular proteins 总被引:41,自引:0,他引:41