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971.
Ancient bones in a good preservation state, ascertained by microscopic techniques, conserve extracellular matrix proteins over thousands of years. With new techniques, intact extracellular matrix proteins from ancient bones and teeth are extracted and separated by one‐dimensional and two‐dimensional electrophoresis. Proteins were identified in Western blots by special antibodies against different human extracellular matrix (ECM) molecules of bone. We have confirmed different types of ECM human bone molecules such as osteonectin, osteopontin, and alkaline phosphatase with specific antibodies in human bone samples from different age groups. Additionally, we selected bone samples from different cultural time periods, such as the Middle Ages, the Bronze Age and the Late Pre‐Pottery Neolithic Phase (PPNB), and teeth from individuals from the Early Middle Ages and from the Late PPNB. The survival of intact extracellular matrix proteins in ancient bones and teeth dating from recent times to the Late PPNB, and reliable techniques to identify these proteins, present a great challenge to further research. A Match Set with PD‐Quest 7.2 shows that only 16% of protein spots in the teeth are also found in the bone of the same individual. In combination with the results of macro‐ and microscopic investigation, biochemical techniques will help us in obtaining a better understanding of bone and teeth in health and disease. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
972.
C. Torres‐Rouff 《International Journal of Osteoarchaeology》2003,13(4):247-251
This paper examines the osteological evidence for a case of long‐term labret use in pre‐Columbian north Chile and the pathological conditions associated with it. The burials from the site of Solcor 3 (AD 400–900) included a complete skeleton associated with two quartz labrets. Analysis of the skeleton of this adult male revealed wear and polish on the labial surface of both mandibular canines, indicating that the labrets were worn as a pair on either side of the midline of the lower lip. In addition to these abrasion facets, there were also areas of periosteal reaction in the alveolar bone of the canines. These patterns were analysed from the perspective of the clinical dentistry literature and compared to archaeological data. It is concluded that this individual's dental health was affected by wearing labrets, although not as seriously as might be expected based on contemporary medical reports. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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974.
Lin-Ti Tan 《Journal of regional science》2001,41(4):601-615
This paper reexamines the welfare implications of three pricing regimes (mill, uniform, and discriminatory) for a monopoly. Assuming linear demand and constant marginal costs, I show that with the introduction of endogenous location choice, uniform delivered pricing may provide the highest social welfare when demands in different markets are sufficiently heterogeneous; whereas discriminatory pricing always dominates uniform pricing when demands in different markets are similar. 相似文献
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Diane Austin‐Broos 《Oceania; a journal devoted to the study of the native peoples of Australia, New Guinea, and the Islands of the Pacific》2000,71(2):150-152
Rednecks, Eggheads and Blackfellas: a study of racial power and intimacy in Australia. By Gillian Cowlishaw Sydney: Allen and Unwin. 1999. Pp. xix + 352. Figures, Maps, Photos & Index $35 相似文献
978.
Margit Szllsi‐Janze 《Berichte zur Wissenschaftsgeschichte》2000,23(1):17-35
Biography as a genre of historiography had been dismissed for some years, criticized for being conservative, resistant to theoretical approaches, and hostile to methodological innovations. But the predominance of a historiography devoted to structures, functions, and statistics has, however, led to a renewed interest in the human factor in history. This paper argues that the pluralism of methods and theories which has emerged thereafter reopened the case for an innovative biography, thus facilitating the convergence of general history and the history of science. 相似文献
979.
Marie‐Luise Bott 《Berichte zur Wissenschaftsgeschichte》2000,23(4):455-457
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