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61.
H Quentmeier M Osborn J Reinhardt M Zaborski H G Drexler 《The journal of histochemistry and cytochemistry》2001,49(11):1369-1378
Antibodies recognizing tissue-specific antigens are widely used to identify the histological origin of tumors. Here we tested the fidelity of selected tissue markers on all 167 solid tumor-derived continuous cell lines in the DSMZ cell lines bank. Most lines had an intermediate filament content consistent with the tumor type from which they were derived. Thus, 93% of all carcinoma cell lines expressed keratin filaments. With certain antibodies, some subclassification was possible. For example, the CK7 keratin 7 antibody can differentiate between colon and pancreas-derived carcinoma cell lines. Cell lines derived from non-carcinomas, in general, did not express keratin but were vimentin-positive. Four of 10 glioma/astrocytoma cell lines expressed GFAP, five of six neuroblastoma cell lines expressed neurofilaments, and the TE-671 rhabdomyosarcoma cell line expressed desmin. When other tissue markers were tested, 12/16 melanoma-derived cell lines expressed HMB-45, while PSA, CA125, and thyroglobulin were less useful. These results demonstrate that cell lines retain some but not all markers typical of the original tumor type and identify certain markers useful in characterizing the histological origin of cell lines. Our data question the identity of some cell lines submitted to the bank in the past. The immunoprofiles of 167 solid tumor-derived and 131 hematopoetic cell lines can be found at www.dsmz.de. 相似文献
62.
Gerti Dücker Christa Schrameyer Margarete Stascheit 《Ethology : formerly Zeitschrift fur Tierpsychologie》1979,51(3):269-281
The significance of massed and distributed practice in discrimination learning to criterion by goldfish was studied. All animals were trained to discriminate between 6 horizontal black and white stripes (positive stimulus) and 2 vertical black and white stripes (negative stimulus). 5 groups of animals, 12 Ss each, got different training programs. Groups varied in number of trials per day (30, 10, 5 successive trials) and in distribution of trials over the day (30 trials given in blocks of 5 with ITI of 1 h or 5 trials, each spaced by an ITI of 1 h). In general animals with a small number of massed trials/day were superior in early acquisition period. When trials/day were spaced the method proved to be more efficient. The training method showed no effect concerning retention. 相似文献
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Margarete Bayer 《Zoomorphology》1924,1(2):373-428
Ohne Zusammenfassung 相似文献
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Michael D. Woodrow Stuart P. Ballantine Michael D. Barker Beth J. Clarke John Dawson Tony W. Dean Christopher J. Delves Brian Evans Sharon L. Gough Steven B. Guntrip Stuart Holman Duncan S. Holmes Michael Kranz Mika K. Lindvaal Fiona S. Lucas Margarete Neu Lisa E. Ranshaw Yemisi E. Solanke Don O. Somers Peter Ward Joanne O. Wiseman 《Bioorganic & medicinal chemistry letters》2009,19(17):5261-5265
Crystallography driven optimisation of a lead derived from similarity searching of the GSK compound collection resulted in the discovery of quinoline-3-carboxamides as highly potent and selective inhibitors of phosphodiesterase 4B. This series has been optimized to GSK256066, a potent PDE4B inhibitor which also inhibits LPS induced production of TNF-α from isolated human peripheral blood mononuclear cells with a pIC50 of 11.1. GSK256066 also has a suitable profile for inhaled dosing. 相似文献
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Linkage Analysis Reveals the Independent Origin of Poeciliid Sex Chromosomes and a Case of Atypical Sex Inheritance in the Guppy (Poecilia reticulata)
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Among different teleost fish species, diverse sex-determining mechanisms exist, including environmental and genetic sex determination, yet chromosomal sex determination with male heterogamety (XY) prevails. Different pairs of autosomes have evolved as sex chromosomes among species in the same genus without evidence for a master sex-determining locus being identical. Models for evolution of Y chromosomes predict that male-advantageous genes become linked to a sex-determining locus and suppressed recombination ensures their co-inheritance. In the guppy, Poecilia reticulata, a set of genes responsible for adult male ornaments are linked to the sex-determining locus on the incipient Y chromosome. We have identified >60 sex-linked molecular markers to generate a detailed map for the sex linkage group of the guppy and compared it with the syntenic autosome 12 of medaka. We mapped the sex-determining locus to the distal end of the sex chromosome. We report a sex-biased distribution of recombination events in female and male meiosis on sex chromosomes. In one mapping cross, we observed sex ratio and male phenotype deviations and propose an atypical mode of genetic sex inheritance as its basis. 相似文献
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How is movement of individuals coordinated as a group? This is a fundamental question of social behaviour, encompassing phenomena such as bird flocking, fish schooling, and the innumerable activities in human groups that require people to synchronise their actions. We have developed an experimental paradigm, the HoneyComb computer-based multi-client game, to empirically investigate human movement coordination and leadership. Using economic games as a model, we set monetary incentives to motivate players on a virtual playfield to reach goals via players'' movements. We asked whether (I) humans coordinate their movements when information is limited to an individual group member''s observation of adjacent group member motion, (II) whether an informed group minority can lead an uninformed group majority to the minority''s goal, and if so, (III) how this minority exerts its influence. We showed that in a human group – on the basis of movement alone – a minority can successfully lead a majority. Minorities lead successfully when (a) their members choose similar initial steps towards their goal field and (b) they are among the first in the whole group to make a move. Using our approach, we empirically demonstrate that the rules of swarming behaviour apply to humans. Even complex human behaviour, such as leadership and directed group movement, follow simple rules that are based on visual perception of local movement. 相似文献