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51.
A lightweight finger printing stand is described which can be adjusted to the proper printing height. Based upon experience printing over 1,100 subjects, 12 advantages of using the stand are suggested. 相似文献
52.
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
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Aquatic environmental impact associated with stream-crossing by a pipeline was monitored at Archibald Creek, B.C. for two years. Water chemistry and benthic macroinvertebrates were used as monitoring tools. Results indicated that impacts arising from stream-crossing were short-term and non-residual.Funded by a contract from Canadian Arctic Gas Study Limited, calgary, to Aquatic Environments Limited, Calgary.Aquatic Environments Limited, Calgary.Aquatic Environments Limited, Calgary. 相似文献
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The effects of phorbol ester on mouse blastomeres: a role for protein kinase C in compaction? 总被引:1,自引:0,他引:1
T L Bloom 《Development (Cambridge, England)》1989,106(1):159-171
The effects of phorbol myristate acetate (PMA) and other activators of protein kinase C on the cytoskeletal organization of mouse oocytes and early embryos have been examined. The effects observed depended on the developmental stage on exposure to PMA. PMA had little effect on the cytoskeletal or microvillous organization of unfertilized oocytes. Interphase cells from embryos prior to compaction showed limited disruption and loss of microvilli when exposed to PMA and foci of polymerized actin remained visible in the cytocortex of embryos up to the early 8-cell stage. When compacted late 8-cell embryos were exposed to PMA, most microvilli were lost and little polymerized actin remained in the cytocortex. PMA also caused loss of microtubules from compact 8-cell embryos under some experimental conditions. Intercellular flattening was both prevented and reversed. The relevance of these observations to the rearrangement of cell-cell contacts and cytoskeletal organization seen during compaction at the 8-cell stage is discussed and a possible role for protein kinase C in the generation of cell polarity proposed. 相似文献
60.
Janine F. Bridges Peter C. Millard John F. Woodley 《Biochimica et Biophysica Acta (BBA)/General Subjects》1978,544(2):448-451
The uptake of free and liposome-entrapped 125I-labelled poly(vinylpyrrolidone) was measured in an intestinal sac preparation from adult rats. An an equal concentration of 125I-labelled poly(vinylpyrrolidone), the rate of uptake of the liposome-entrapped material was four times that of the free macromolecule. 相似文献