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Highlights
  • •Sufficient tumor tissues are often unavailable large HLA peptidome discovery.
  • •Using patient derived xenograft (PDX) tumors can overcome this limitation.
  • •The large PDX HLA peptidomes expand significantly those of the original biopsies.
  • •The HLA peptidomes of the PDX tumors included many tumor antigens.
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This study questions the customary thesis according to which the dominant status of the ashkenazim (European Jews) over the mizrachim (Middle Eastern and North African Jews) in Israeli society is to be explained by the earlier arrival of the former in Palestine. It does so by demonstrating that an early wave of Yemenite Jews, who arrived in Palestine simultaneously with the founding fathers, remained in a subservient social position. Archival sources, memoirs, and contemporary newspapers are used to explain the low status of Yemenite Jews by reference to the broader context of the Jewish‐Arab conflict as it took shape in Palestine's labour and land markets.  相似文献   
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Experiments were done to test the hypothesis that the avian gut is colonized by cells derived from both vagal and sacral regions of the neural crest. A fluorescent dye, diI (1,1-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate), and a replication-deficient retrovirus (LZ10; Galileo et al. 1990) were employed as tracers. Since LZ10 was constructed with lacZ of E. coli as a reporter gene, infected cells were identified by demonstrating beta-galactosidase immunoreactivity. DiI and LZ10 were injected between the neural tube and surface ectoderm (before the migration of crest cells away from the injection sites) at vagal, truncal (diI only), or sacral axial levels. The bowel was examined 4 days later in order to allow crest-derived cells sufficient time to migrate to the gut. Following injections of either tracer into the vagal crest, labelled cells were found in the gizzard and duodenum. When diI or LZ10 was injected into the sacral crest, labelled cells were seen in the post-umbilical bowel and ganglion of Remak. In the hindgut, marked cells were concentrated in the mesenchyme, just internal to the serosa, and were never observed rostral to the umbilicus. No fluorescent cells were ever found in the bowel following truncal injections of diI, although such cells were observed in sympathetic ganglia. Labelled cells were always found in dorsal root ganglia, no matter which tracer or level of the crest was injected. In embryos injected with LZ10, infected cells in the gut and dorsal root ganglia displayed a neural crest marker (NC-1 immunoreactivity). These observations confirm that the gut is colonized by cells from the sacral as well as the vagal region of the neural crest and that the emigrés from the sacral crest are confined to the post-umbilical bowel.  相似文献   
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We have used quantitative DNase I footprinting to measure the relative affinities of four disubstituted and two monosubstituted amidoanthraquinone compounds for intermolecular DNA triplexes, and have examined how the position of the attached base-functionalized substituents affects their ability to stabilize DNA triplexes. All four isomeric disubstituted derivatives examined stabilize DNA triplexes at micromolar or lower concentrations. Of the compounds studied the 2,7-disubstituted amidoanthraquinone displayed the greatest triplex affinity. The order of triplex affinity for the other disubstituted ligands decreases in the order 2,7 > 1,8 = 1,5 > 2,6, with the equivalent monosubstituted compounds being at least an order of magnitude less efficient. The 1,5-disubstituted derivative also shows some interaction with duplex DNA. These results have been confirmed by molecular modelling studies, which provide a rational basis for the structure-activity relationships. These suggest that, although all of the compounds bind through an intercalative mode, the 2,6, 2,7 and 1,5 disubstituted isomers bind with their two side groups occupying adjacent triplex grooves, in contrast with the 1,8 isomer which is positioned with both side groups in the same triplex groove.  相似文献   
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