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81.
Jathan Sadowski 《对极》2020,52(2):562-580
Digital platforms are a nearly ubiquitous form of intermediary and infrastructure in society. By positioning platforms in the geographical political economy/ecology literature, this paper provides a critical analysis of platforms as a dominant form of rentier in contemporary capitalism. In doing so, I extend this work on rent theory beyond applications to land and nature so that it also includes platforms and data. I argue that the rapid rise of the “X-as-a-service” business model across nearly all sectors of the economy is creating rentier relations by another name. This model is premised on the platform latching onto and inserting itself into the production, circulation, or consumption process, thus creating opportunities to capture value. To better understand the operations and implications of platforms, I outline three key mechanisms: data extraction, digital enclosure, and capital convergence.  相似文献   
82.
The discovery of polymeric DNA in charred wheat grains and other burnt plant remains prompted us to examine a set of cremated bones for the presence of ancient DNA. Extracts of cremated bones from an early Bronze Age cemetery cairn were analysed by hybridization probing and the polymerase chain reaction. Hybridization with two probes targeting human DNA resulted in strong positive signals. Polymerase chain reactions directed at a multicopy sequence in human nuclear DNA were successful, extracts of five burials giving amplification products of the expected size. Exploitation of ancient DNA in cremated bones could be of great value in archaeology as it may enable information pertaining to sex and kinship to be obtained from fragmented material.  相似文献   
83.
The origin and evolution of the infectious disease tuberculosis (TB) and its pathogens is still not fully understood. An important effort for a better understanding of the underlying mechanisms of TB evolution lies within the investigation of skeletal and mummified material dating back several thousand of years. In this work, molecular data from mummified and skeletal material from different time periods of the Old World are compared, and the current status of ancient mycobacterial DNA analysis in ancient human remains is discussed, with particular reference to the genetic evolution of human TB. The molecular analysis of material from southern Germany (1400–1800 AD), Hungary (600–1700 AD) and Egypt (3500–500 BC) revealed high frequencies of TB in all time periods. In several individuals from ancient Egypt the mycobacterial DNA could be further characterised by spoligotyping. Thereby, evidence for ancestral M. tuberculosis strains was found in the pre‐ to early dynastic material from Abydos (3500–2650 BC), while typical M. africanum signatures were detected in the Middle Kingdom tomb in Thebes‐West (2050–1650 BC). Samples from the New Kingdom to Late Period tombs (1500–500 BC) were characterised as modern M. tuberculosis strains. In concordance with other studies on ancient skeletal and mummified samples, no evidence for the presence of M. bovis was found. These results contradict the theory that M. tuberculosis evolved from M. bovis during domestication, but supports the new scenario that M. tuberculosis probably derived from an ancestral progenitor strain. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
84.
The polymerase chain reaction has been used to extract ancient DNA from a wide range of different types of material. We have considered the possibility of finding residual bacterial DNA in bone that may have been infected with Mycobacterium tuberculosis using this technique. We propose a method of collecting samples and testing for the presence of degraded genetic material in ancient bone. The steps of the polymerase chain reaction are detailed and discussed, as are those for the preparation of the bone sample. Results obtained would suggest that this technique could have wide application in osteoarchaeological research by giving us new information on diseases of antiquity. Future avenues for the investigation of bacterial DNA in ancient bone are suggested.  相似文献   
85.
X.‐Q. Chen  B. Zhang  Z. Zhang 《Archaeometry》2019,61(6):1417-1429
Because it is often difficult to preserve fragile relics in situ at underwater cultural heritage sites, it is sometimes necessary for relics to be extracted and moved to a controlled environment on land for protection and study. This paper discusses the feasibility of using the volatile organic compound veratraldehyde as a temporary consolidant for underwater fragile relics extraction. The results show that different materials (iron, tile, sand, wood) under water can be bonded together and extracted when using veratraldehyde. The fact that veratraldehyde is difficult to spread on the surface of underwater objects is a problem that can be solved by adding a layer of strong hydrophobic polypropylene (PP) fibres onto the object, serving as a ‘package' for the relics. Under laboratory conditions, we used veratraldehyde and PP fibres to extract broken tiles from underwater sand onto an exhibition stand. The broken tiles, in both condition and distribution, were safely and completely retained as the veratraldehyde was slowly removed by the soaking process. This work fills a gap in knowledge about temporary consolidant materials in underwater archaeology, and provides a new method for extracting underwater fragile cultural relics without damaging them.  相似文献   
86.
Discussion about local decision making tends to overlook rural and remote youth engagement. Resource extractive industries are, however, fixtures in many rural, remote, northern, and Indigenous communities in settler colonial British Columbia, Canada. These industries shape youths' perceived options for social and economic ventures when they are looking towards their futures. By engaging literature on climate change, settler colonialism, and critical Indigenous studies, and drawing on empirics from workshops conducted with youth from northern British Columbia, this paper explores how rural and remote northern and Indigenous youth engagement and perspectives can transform discussions on climate change and resource extraction. The paper documents how rural and northern youth have been engaged in environmental decision making, particularly in light of resource extraction. The paper also suggests that environmental decision making has at times been extractive itself. The paper concludes that when engaged meaningfully, youth desire to work collectively against social and environmental injustices.  相似文献   
87.
The recovery of ancient DNA from archaeological wheat samples under different preservation conditions was assessed using a number of genetic markers. It was possible to amplify nuclear DNA from desiccated grains but not from charred. The desiccated grain was from a pre-Hispanic grain silo in Gran Canaria and showed excellent DNA preservation, enabling the amplification of the ribosomal DNA markers IGS and ITS, the upstream region of the HMW-glutenin locus and single-locus nuclear microsatellites. Our results demonstrated the presence of both durum and bread wheat in an assemblage of naked grain. We were also able to identify different genotypes in durum wheat and compare these with extant landraces, providing insights into the agrarian practices of the ancient Canarians and the origin of their crops.  相似文献   
88.
Sex identification of skeletal remains based on morphology is a common practice in Zooarchaeology. Knowledge of the sex distribution of slaughtered or hunted animals may help in the interpretation of e.g. hunting or breeding strategies. Here we investigate and evaluate several osteometric criteria used to assess sex of cattle (Bos taurus) metapodia using molecular sex identification as a control of the metric data. The bone assemblage used to assess these new criteria derives from the Eketorp ringfort in the southern parts of Öland Island in Sweden. One hundred metapodia were selected for molecular analysis of sex and we were able to genetically identify the sex of 76 of these elements. The combined results of the molecular and osteometric analyses confirm a significant size difference between females and males for several measurements for both metacarpals (Mc) and metatarsals (Mt). Our results show that some measurements are applicable for metapodials. These measurements include the slenderness indices such as the Mennerich’s index 1 and 3, as well as the distal breadth (Bd), the breadth between the articular crests (Bcr), and the maximum breadth of the lateral trochlea (BFdl). We show that they can be used for sexing of both metacarpals and metatarsals. The latter measurements offer an opportunity to study fragmented elements and thus a higher number of elements may be utilized for morphological sexing of archaeological bones. Size comparisons of Mc and Mt may also aid in the separation of bulls and oxen.  相似文献   
89.
Here we demonstrate the successful extraction and amplification of target species DNA from artefacts made of whale baleen collected from excavations of past palaeo-Eskimo and Inuit cultures in Greenland. DNA was successfully extracted and amplified from a single baleen bristle of 1.5 cm length dated based on archaeological context to the period of the Saqqaq culture, more than 4000 years ago and following decades of storage at room temperature at the National Museum. The results reveal ancient baleen in archaeological material as a potential source of DNA that can be used for population genetic studies. We conclude that genetic investigation of historical baleen collections can contribute to our knowledge of the prehistoric population genetics of baleen whales, for example by quantifying the impact of modern whaling on the genetic diversity of bowhead whales.  相似文献   
90.
Our multidisciplinary study of historic Thoroughbred horses solves two long‐running mysteries in racing history. Eclipse, the greatest racehorse ever known, never lost a race. His skeleton is housed in the Royal Veterinary College, London; however, there is controversy over its authenticity. The 1880 Epsom Derby was won by Bend Or. In one of the great controversies of Thoroughbred racing, the owners of Bend Or were accused of swapping him with another horse, Tadcaster, whose maternal pedigree was more prestigious. Bend Or's skeleton resides at the Natural History Museum, in London. Eclipse and Tadcaster were both extremely popular at stud, and the vast majority of racehorses today are descendents. We compared mitochondrial DNA haplotypes of living and historic Thoroughbred skeletons, including those of Eclipse and Bend Or. Additionally, we compared skeletal morphometrics of Eclipse's skeleton with measurements taken at autopsy. Carbon and nitrogen stable isotopes of a range of skeletal elements were compared in order to establish that the Eclipse skeleton was that of a single horse. Our multidisciplinary data suggest that the putative skeleton is consistent with that of Eclipse. In contrast, mitochondrial DNA haplotype sharing indicated that the skeleton known as Bend Or is most probably that of Tadcaster.  相似文献   
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