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91.
阿勒泰地区位于新疆的最北端,与欧亚草原之间存在丰富的文化交流,而冶金技术的发展与人类文明紧密相关,为探究新疆阿勒泰地区的冶金发展情况,选取9件草原游牧文化的代表性器物——铜鍑和马具,使用金相显微镜、扫描电子显微镜和X射线能谱仪及双通道电感耦合等离子体发射光谱仪,对16个样品进行金相组织分析和成分分析,并探讨其制作技术特征。研究发现阿勒泰地区的早期铁器时代铜器普遍采用范铸工艺,其成分主要为红铜、砷铜、铅砷青铜。该分析结果为研究新疆阿勒泰地区的冶金发展提供了重要参考。  相似文献   
92.
Examining recently excavated burnt burials, we explore the potential of spatial analysis to contribute to the understanding of changes that human body goes through during burning and relocation to the place of secondary deposition. Artificial heat decomposition of a body is a complex process that consists of several stages of intentional manipulation with the body. Each stage can be biased by several accidental factors which then significantly change the final archaeological record. We focussed on the post‐burning stage, especially the pathways of bone fragments to secondary deposition. We investigated spatial distribution and weight of bones in urns and pits and asked whether it is possible to observe their intentional arrangement. The trend of bone arrangement could be distinguished in most cases. Bones of peripheral parts of body were typically situated at the bottom; skull bones were usually concentrated in the upper part. However, the weight underrepresentation of all investigated burials was apparent. Deposition of selected burnt bones suggests their careful collection from the pyre and complex post‐mortem manipulation. Our detailed analysis aims to reconstruct particular steps executed during funeral rites of past populations. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
93.
Using modern samples of known kin, this paper evaluates two fundamental aspects of kinship analysis in archaeological contexts: (1) choice of data (dental metrics or morphology) and (2) analytical approach (multivariate, distance‐based approach or a ‘rare trait’ analysis). Stone dental casts were analysed from 155 female individuals from four sampling locations in Kenya. Of these 155 individuals, only three pairs were close kin: mother–daughter, sister–sister, and first‐cousin–first‐cousin dyads. After variable winnowing, inter‐individual distances or similarities were calculated using 11 odontometric variables and 25 dental morphological variables. Resulting distance matrices were ordinated in two dimensions using multidimensional scaling. Odontometric data performed relatively well at identifying known relative pairs, but the results were heavily affected by choice of similarity measure (e.g. Euclidean distances vs. Gower coefficients) and pre‐analysis data treatments (e.g. raw data vs. principal components). Dental morphological data performed comparably with odontometric data but were slightly less effective. Rare traits were identified and compared among relative pairs for concordance, with mixed results. Rare morphological features were randomly distributed throughout the population and were not exclusively found in close kin. In combination, results indicated the sister–sister dyad was most consistently identified; however, in no analysis were relatives more phenotypically similar than all random pairs of unrelated individuals. A multivariate, distance‐based approach was more effective than rare traits at identifying relative pairs, but even under ideal circumstances, there is not enough variation present in the dentition to faithfully identify close relatives in the absence of contextual archaeological data. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
94.
ABSTRACT This paper investigates the extent to which house–price uncertainty affects the transition of renter households into homeownership. Using a 14‐year household panel from the Panel Study of Income Dynamics during the years 1984–1997 and measures of the time‐varying risk and return to owner‐occupied housing, we estimate a Cox proportional hazard model of the effect of house–price volatility on the transition into homeownership. Results indicate that house–price uncertainty has a negative and dramatic impact on transitions into homeownership. In addition, we find that the low‐wealth renters are particularly sensitive to house–price risk.  相似文献   
95.
One of the main factors involved in entheseal changes (EC) aetiology may be related to the physiological limits of biomechanical loading fixed during bone development, such that higher load during childhood and the adolescent growth spurt leads to a lower frequency of EC during adulthood. In this sense, it is possible that ECs may be related to overloading beyond an individual's normal physiological limits as established during childhood and adolescence. This meta‐analysis tested this aetiological possibility by studying the influence of terrain on the entheses of the lower extremities. The hypothesis is that individuals who inhabited rugged terrain have lower EC than those living in flat terrain. This is because biomechanical loads associated with rugged terrain will lead to a higher normal capacity (defined during skeletal development) mitigating the probability of overloading compared to those living in flat terrain who will therefore have a higher frequency of ECs. To test this, papers reporting EC frequencies in the lower limbs were analysed alongside the local terrain. Terrain was defined into two categories: flat or rugged based on altimetry profile, i.e. the average elevation gains and losses along four specific paths (North‐South, East‐West, Northwest‐Southeast, Southwest‐Northeast). Odds ratios were calculated to compare rugged and flat terrain. The overall results are consistent with the hypothesis that overloading is a factor in EC aetiology. However, when the analysis is conducted by sex and side, this general trend does not always occur. Limitations such as the lack of standardized age ranges could be affecting the outcome, i.e. older individuals have a higher frequency of ECs. The findings of this analysis suggest that the theoretical assumptions associated with the cause of ECs require further testing and evaluation. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
96.
Archaeological research in the Atacama Desert has recovered evidence of considerable cultural variability. This variability seems to have increased during the Late Intermediate Period (AD 950–1400). The oasis of Quillagua, located at the margins of the Loa River in northern Chile, between the Andes and the coast (70 km from the Pacific Ocean), has shown important evidence regarding this cultural diversity. The variety in the archaeological evidence found at Quillagua has been interpreted as the result of two different cultural influences at the oasis: the Pica‐Tarapacá who occupied the coastal and inland regions to the north of Quillagua and the Atacama who occupied the oasis and fertile areas southeast of Quillagua. Here, we present the results of stable carbon, nitrogen and oxygen isotope analyses of 23 individuals recovered from the Cementerio Oriente in Quillagua, in order to test whether the observed cultural variability is also reflected in diet and mobility patterns. Results from carbon and nitrogen isotope measurements indicate the importance of marine protein, as well as a contribution of maize in the diet of some individuals. Four individuals show low δ18O values, suggesting a possible highland or non‐local origin, whereas values for the remaining individuals are consistent with lowland populations. Together, the results support the idea that the Quillagua oasis represented an important site of interaction between the Tarapacá and Atacama cultures, with close contacts with the coast but also with the presence of individuals from the highlands. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
97.
This study investigates temporal changes in dietary practices in the Caribbean archipelago during the Ceramic Age (400 BC–AD 1500), through analyses of dental wear and pathology. Some previous studies in the region have suggested that diet and subsistence practices changed over time due to increasing sociopolitical complexity, climate change, or adaptation to island environments rich in marine resources. Both horticultural/agricultural intensification and increased marine focus of the diet over time have been posited, based among other things on faunal and botanical remains, and early ethnohistorical accounts. Local and micro‐regional stable isotope studies of temporal dietary variation have found few indications for change over time, and large regional isotope studies are still lacking. Dentitions from sites throughout the region dating to the Early Ceramic Age (400 BC–AD 600/800) and the Late Ceramic Age (AD 600/800–1500) were analysed in order to assess temporal differences. Intra‐individual rates of wear were calculated using the difference in degree of wear between the adjacent molars and the two groups were compared with principal axis analysis. Caries, antemortem tooth loss, abscesses and dental calculus were recorded per individual and per tooth/socket, and population caries and antemortem tooth loss rates were assessed and compared by age group, tooth class and sex. Comparisons between the two occupation periods revealed significant differences in the rate of dental wear and pathology, indicating a shift in dietary practices over time, coinciding with known social changes. The increase in pathology rates suggests a rise in the consumption of cariogenic foods or preparation techniques that increase cariogenicity. The decrease in rate of wear over time indicates a reduction in abrasivity of the diet. Together these data suggest that there was a growing focus on refined, cariogenic foods, likely horticultural/agricultural produce. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
98.
Early Stone Age cut marks created during tool‐assisted carnivory potentially offer inferences into hominin butchery behaviour and access to complete or defleshed carcasses. Actualistic butchery trials of 16 goat and cow half‐carcasses were completed by an experienced butcher with replicated Oldowan tools to investigate how the geometric organisation of cut mark clusters reflects flake versus core tool use and bulk muscle versus scrap defleshing. A cluster of cut marks is defined as a series of adjacent cut mark striations that occur at an anatomical location and are bounded by unmarked cortical surface. Tool type and butchery action were predicted to differentially mark certain long bone portions and influence cluster attributes. Moulds of 613 cut mark clusters were photographed and measured using ImageJ software (National Institutes of Health, Bethesda, Maryland, USA) for cluster area, cut mark count, median cut mark length and standard deviation of cut mark length and angle. Analysis suggests the following results: (i) cluster attributes are correlated;(ii) changes in cluster geometry are related to increasing cut mark count and length but not tool type or defleshed muscle amount; (iii) large clusters occur on large animals; and (iv) long bone midshaft portions are cut‐marked during both bulk and scrap muscle defleshing. Analysis of 179 cut mark clusters on long bone shafts of sizes 1–4 mammals from three Okote member assemblages at Koobi Fora, Kenya, shows that archaeological clusters have a similar number of marks when compared with experimental clusters but are significantly smaller, have shorter median marks and include less deviation in mark length and angle. Archaeological clusters corroborate that increasing area is positively correlated with cut mark count, median mark length and standard deviation of mark length and angle. A quantitative inferential model that links cut mark cluster geometry to tool type or the amount of muscle defleshed is not supported by these data. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
99.
A range of archaeological and palaeoclimatic studies use isotopic analyses of ungulate hypsodont tooth enamel. Such studies commonly assume a constant growth rate, though this has not been fully tested. Here, we use stable isotope analyses of sequential enamel samples to study horse tooth growth. We fit the data using models corresponding to constant and exponentially decreasing rates of growth, and compare the results to metrical data showing the geometry and timing of apposition. The results indicate enamel apposition and maturation advances at an exponentially decreasing rate. An understanding of this variable growth rate is crucial for interpreting isotopic data from equid teeth.  相似文献   
100.
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