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151.
Dental calculus extracted from the teeth of 28 prehistoric human skeletons from coastal and valley archaeological sites in northern Chile that date from the Archaic period (∼2300 BC) to the Late Intermediate period (AD 1476) was analyzed for stable isotope (δ15N, δ13C) compositions. δ15N compositions were extremely heavy (+17.8 to +33.1‰), but comparable to some studies using conventional human biomaterials (hair, nail, muscle) at other prehistoric sites in northern Chile. There was a negative correlation between δ15N and δ13C for coastal sites, but a positive correlation for valley sites. Results for the valley sites point to a diet that was influenced by marine resources throughout all time periods. The unusually heavy δ15N values for the coastal sites require a dietary component with a δ15N composition significantly heavier than that of marine resources. The hyper-aridity at the study area (mean annual rainfall of 0.5–0.6 mm/year) is a likely contributing factor to the production of heavy δ15N values, but is unlikely to account for the heaviest δ15N values (>+30‰). One possible explanation for the heaviest δ15N values is that dietary components were impacted by isotopically-heavy guano, which is abundant in the region. Guano may have been used as a fertilizer during crop cultivation at the onset of the Formative period, continuing through the Historic period after Spanish contact. The indirect impact of guano from abundant bird habitats in the region may have influenced wild foodstuffs harvested throughout the pre-agricultural period. Results provide support for the utility of dental calculus as a proxy for obtaining stable carbon and nitrogen isotope signatures for use in paleodietary studies.  相似文献   
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A technique for establishing source provenance for pegmatite quartz artifacts was developed using a quarry sample from the Churchill River basin of northern Manitoba and Saskatchewan. Secondary ion mass spectrometry (SIMS) was used to quantify Ti, Ge, Th, and U trace element concentrations and Pb isotope ratios, coupled with qualitative visual characteristics to distinguish between pegmatite quartz from different archaeologically exploited sources in the Churchill River basin region. The technique was also applied to a small sample of quartz artifacts recovered from sites in and around the study area in a preliminary attempt to assign or rule out raw material provenance to characterized sources.  相似文献   
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Zooarchaeological analysis typically involves implementing a suitable sampling strategy that provides meaningful information representative of a site under investigation. To test the efficacy of how various sampling procedures can influence interpretation of a faunal assemblage, we analyzed in full, a large assemblage of mollusks (minimum number of individuals [MNI] = 58,000+) from the late Ceramic Age (ca. AD 850–1440) site of Coconut Walk on the island of Nevis (northern Lesser Antilles, Caribbean). These remains were recovered from 25 discrete 1 × 1 m units within a larger 5 × 5 m trench that overlaid a dense midden deposit. Using statistical procedures, we compared the results of the number of identified specimens (NISP), MNI, and weight (g) of each mollusk taxon between both units and plana to determine how different sampling strategies would have affected the interpretation of mollusk composition across space and time had different sampling procedures been used. The results reveal that sampling less than 16% (4 out of 25 squares for this study) of a midden is likely to produce results outside of a 95% confidence interval for the population composition, with samples of connected squares having a higher likelihood to lie outside the interval. Discerning change between plana (or layers) may require a larger sample (i.e., 16%+). In addition, samples selected randomly or judgmentally will produce similar results, provided that proper spacing is given between units. The data in this case suggest that the midden was efficiently sampled for midden composition and key species at a rate of 16% of the surface area.  相似文献   
154.
Azurduya gen. nov. (Brachiopoda: Camarotoechiidae) is described from Early Carboniferous sequences in the Argentine Precordillera and northern Chile. Marine assemblages and the palynoflora associated with this genus suggest a Tournaisian age. The type species Azurduya chavelensis (Amos, 1958) is reviewed and redescribed from material from the type locality. Additional material from equivalent localities in the Rio Blanco Basin (La Rioja and San Juan provinces, Argentine Precordilera) has been used to understand ontogenetic changes as well intraspecific variation. Azurduya cingolanii sp. nov. is proposed.  相似文献   
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During the tumultuous time of financial and colonial expansion between 1825 and 1855, both Charles Dickens and John Galt published picaresque novels depicting transatlantic travel and land speculation. If emigration is the act of permanently leaving one's homeland and living in another, then neither novels' eponymous protagonist Martin Chuzzlewit nor Lawrie Todd is an emigrant. By reading Martin Chuzzlewit (1843–44) and John Galt's Lawrie Todd (1830) alongside nineteenth-century developments of the geo-political and financial spheres, this article shows how these works form a counter-narrative to traditional novels of emigration. Both protagonists leave Britain with the explicit intent to seek their fortune in America through engagement with land speculation companies. Though the characters' experiences of transatlantic financial speculation is dichotomous (with Todd becoming rich and Chuzzlewit losing all he has), both characters ultimately return to Britain. In these counter-narratives, we argue that America is deployed as Britain's financial periphery, rather than an alternative imperial centre, working to entrench British nationalism through transatlantic financial speculation. It is through the act of returning from America that Dickens and Galt counter typified emigration narratives that represent the choice to emigrate to America as synonymous with abandoning the Empire for the ‘Great Republic’. Instead, Dickens and Galt show how America can be exploited as a financial extension of Empire where Britons can maintain national loyalty while simultaneously responding to an unstable global financial market that was increasingly dependent upon speculation and foreign investment practices.  相似文献   
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