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First appearing in 2000, and with 20,000 copies sold as it entered its sixth printing in 2004, Richard Trudgen's Why Warriors Lie down and Die is a minor publishing phenomenon. Although scholarly forums have generally ignored the book, Christian media outlets, the popular press and neo‐conservative political activists have enthusiastically received and promoted it. An examination of the merits of Why Warriors Lie down and Die suggests that its popularity is only partly explained by original observations or insights on the part of the author. The most important explanation, and implication, of the book's remarkable take‐up lies in the opportune way in which it corresponds with now ascendant neo‐conservative political perspectives on indigenous policy. 相似文献
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Kate Jolly 《BMJ (Clinical research ed.)》1991,303(6804):716-717
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Jason L. Schamber James S. Sedinger David H. Ward Kate R. Hagmeier 《Journal of Field Ornithology》2007,78(1):74-82
ABSTRACT. Latitudinal variation in population structure during the winter has been reported in many migratory birds, but has been documented in few species of waterfowl. Variation in environmental and social conditions at wintering sites can potentially influence the population dynamics of differential migrants. We examined latitudinal variation in sex and age classes of wintering Pacific Black Brant ( Branta bernicla nigricans ). Brant are distributed along a wide latitudinal gradient from Alaska to Mexico during the winter. Accordingly, migration distances for brant using different wintering locations are highly variable and winter settlement patterns are likely associated with a spatially variable food resource. We used resightings of brant banded in southwestern Alaska to examine sex and age ratios of birds wintering at Boundary Bay in British Columbia, and at San Quintin Bay, Ojo de Liebre Lagoon, and San Ignacio Lagoon in Baja California from 1998 to 2000. Sex ratios were similar among wintering locations for adults and were consistent with the mating strategy of geese. The distribution of juveniles varied among wintering areas, with greater proportions of juveniles observed at northern (San Quintin Bay and Ojo de Liebre Lagoon) than at southern (San Ignacio Lagoon) locations in Baja California. We suggest that age-related variation in the winter distribution of Pacific Black Brant is mediated by variation in productivity among individuals at different wintering locations and by social interactions among wintering family groups. 相似文献
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Summary In a series of 450 products of conception received for cytogenetic analysis, tissue culture was attempted on 309, and karyotypes were established using banding techniques in 154 singleton specimens. Abnormalities of karyotype were identified in 19%; of these abnormalities, 48% were autosomal trisomies. Gestational age was decreased in the abnormal specimens, and their developmental age was retarded by comparison with their gestational age. Factors contributing to the relatively low incidence of abnormality are examined. The major factor appears to be the clinical interest of collaborating staff, leading to selection, either intentional or unintentional, of particular phenotypes and hence a non-random series. A negative relationship is suggested between frequency of monsomy X and autosomal trisomy, both being associated with maternal age. 相似文献
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New developments in magnetic labelling techniques for cells and microspheres have extended the useful range of magnetic separation, particularly high gradient magnetic separation, into biotechnical areas. The basic magnetic principles involved are reviewed and representative samples of labelling techniques and results drawn from the past three years are presented. Illustrative examples of large scale operation in other industries are also presented, demonstrating the potential of the biotechnological applications. 相似文献
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J E De Vries F H Kornips J Wiegant P M Moerkerk N Senden B Schutte J P Geraedts F T Bosman J Ten Kate 《The journal of histochemistry and cytochemistry》1992,40(7):1053-1058
We describe the combination of hot banding with fluorescence in situ hybridization as a rapid and efficient method to identify integration sites of transfected DNA sequences in chromosomes. As a test system we used SW480 EJ2, a clonal cell line obtained after transfection of SW480 with pSV2neoEJ, a plasmid containing a point-mutated, c-Ha-RAS oncogene. Nick-translated probes were compared with random primed-labeled probes to evaluate their relative efficiency in fluorescence in situ hybridization. The fluorescence signals were quantified in interphase nuclei by confocal scanning laser microscopy. Nick-translated probes were found to yield better results. Hot banding followed by fluorescence in situ hybridization localized the integration site of pSV2neoEJ in SW480 EJ2 at the site of a translocation on a marker chromosome Xp+. The combination of fluorescence in situ hybridization and hot banding can be used to (a) rapidly and efficiently analyze integration sites in large numbers of transfectants, (b) assess the clonality of transfected cell lines, and (c) localize the site of integration of transfected genes in the recipient genome. 相似文献