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981.
This project follows on from an initial study of Celtic gold coins from the Middle Rhine/Moselle region, which was based on material found at the Martberg, a Late Iron Age/Roman sanctuary and settlement (River Moselle, western Germany; Bendall 2003 ). The earlier work was expanded to encompass over 100 examples of various other regional Celtic gold coinages from the collection of the Römisch‐Germanisches Zentralmuseum, Mainz. The alloy (Au–Ag–Cu) and trace element compositions (in particular Ni, Sb and Pt) were determined by EPMA and LA–ICP–MS, respectively, and their Pb isotope signatures were measured by LA–MC–ICP–MS. Of the 28 trace elements measured, only Ni, Sb and Pt were found to show meaningful variations and so only they are presented here. In particular, differences in the Pt/Au ratios between various groups of earlier coinage (imitations of Philippus and Alexander/Nike staters, Sch. 23 and some early Boian coins) on the one hand, and the majority of the Boian and the southern rainbow cup coinages on the other, indicate a significant difference in the gold sources exploited for these regional coinages. The Pb isotope data confirm previous conclusions that the contribution of gold to the total lead in the Au–Ag–Cu coin alloys can be detected, especially for coins with over 70% gold, and show that possible gold sources include both eastern Mediterranean and Alpine sources. Combining the Pb isotope data with the Pt/Au ratios allows the potential gold sources to be further differentiated.  相似文献   
982.
983.
Osteoporosis is a condition of reduced total bone mass per unit volume for the normal ratio of bone mineral to bone matrix. The present work deals with the investigation and evaluation of osteoporosis in ancient Egyptians of two social classes from the Old Kingdom in Giza. The aims of this study are to provide information about the lifestyle and health status of ancient Egyptians, and to detect the causes of osteoporosis. The material consisted of 74 skeletons (43 males and 31 females) from two different social classes (high officials and workers). Skeletons were excavated from the Giza Necropolis and belonged to the Old Kingdom (2687–2191 BC). Dual energy X‐ray absorptiometry (DEXA) was used to measure bone mineral density (BMD) at different skeletal sites (radius, fourth lumbar vertebra and head of femur). Moreover, scanning electron microscopy (SEM) was used to show the microarchitectural structure of the bone. Results showed a significant decrease of BMD values in old age groups compared with younger ones in both sexes. In addition, SEM of trabecular bone in osteoporotic cases demonstrated that the horizontal trabeculae were more affected than the vertical trabeculae. Comparison between high officials and workers revealed that osteoporosis was more frequent in male workers than in male high officials, and in female high officials than in female workers. An elevated prevalence of osteoporosis among male workers may be related to the effects of nutritional stress and excessive workload, while a sedentary lifestyle may have played a role in the occurrence of osteoporosis among female high officials. Moreover, osteoporosis occurs earlier and more frequently in females than males, which may be related to the hormonal changes that accompany the menopause in females. This study emphasises the importance of gender and lifestyle factors in influencing the severity of osteoporosis. Age‐related bone loss at most skeletal sites is noted in both sexes of ancient Egyptians. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
984.
Two concentrations of animal bones, almost exclusively from small mammals and wild birds, were found within the destruction debris of a Roman bath complex in Sagalassos (SW Turkey). The overall species spectrum, skeletal element representation, fragmentation and preservation condition of the bones indicate that they represent the prey remains of a large nocturnal avian predator, more precisely the eagle owl (Bubo bubo). Differences in skeletal element representation and in prey species' spectrum show that the two bone clusters derive from pellets deposited near a nest site and a roost site, respectively. Radiocarbon dates obtained from the bones indicate that eagle owls lived in the collapsing bath complex during the second half of the 6th to the beginning of the 7th century AD, before the final abandonment of the town. The MNI of the prey animals found at the nest site, confronted with the daily dietary needs of a female eagle owl and its young, indicates repetitive use of the same place during several years. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
985.
Skeletal weight and/or weight of the different bones of the human skeleton are currently used in a wide range of applications such as archaeological cremations and forensics. Still, few reference values are available that compare the mean weights for the different skeletal parts. In this paper we present new reference values for total skeletal weight, including the weight of the different skeletal bones based on a modern Portuguese Identified Skeletal Collection (CEI) curated in the Museum of Anthropology of the University of Coimbra (Portugal). The mean weight of the entire skeleton for the CEI pooled sample is 3323.8 ± 779.6 g. Sex and age differences were investigated. As expected, males display heavier bones, at a statistically significant level. The mean weight of the male skeletons is 3850 g, and 2797.6 g for the female sample. Age differences were found, especially for the female samples in the 29–39 versus 50–59 and/or >60 age groups, probably as a consequence of age‐related bone loss in post‐menopausal women. For the male sample, no clear age‐related trend was observed but for the unexpected result that the second highest bone weight recorded is in the oldest age group (>60 years). This could result from high mechanical loadings and thus greater bone robusticy and amount of cortical bone. The percentage of weight of the different parts of the skeleton was also calculated. These new values can be quite useful in the study of very fragmentary and/or commingled human remains, recovered from historic or forensic contexts, since the complete identification, by side, of the remains is not necessary. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
986.
Novel technologies linked to women and men through identity-demarcated tasks and knowledge sets can potentially have differential and even long-term effects on each group. This study follows the trajectory of two significant imports into the coastal western Alaskan system, the firearm and the metal cook pot. These imports had different implications for coastal Yup’ik women and men, young and old. Over time the gun became an integral piece of a man’s tool kit and one that had the potential to boost production and thus a man’s access to status-building. However, these same tools had the potential to undermine the apprenticeship system of male authority. Likewise, the metal cook pot replaced the productive oversight and skill set of elder women’s ceramic production but created paths of independence for younger Yup’ik women. These changes in technology destabilized relative balances of gender and age based status, security, and authority and fashioned new gender and age based social and economic opportunities and limitations.  相似文献   
987.
988.
The fluorite deposits of Asturias (northern Iberian Peninsula) are hosted by rocks of Permo‐Triassic and Palaeozoic age. Fluid inclusions in ore and gangue minerals show homogenization temperatures from 80 to 170°C and the presence of two types of fluids: an H2O–NaCl low‐salinity fluid (<8 eq. wt% NaCl) and an H2O–NaCl–CaCl2 fluid (7–13 wt% NaCl and 11–14 wt% CaCl2). The low salinity and the Cl/Br and Na/Br ratios (Cl/Brmolar 100–700 and Na/Brmolar 20–700) are consistent with an evaporated sea water origin of this fluid. The other end‐member of the mixture was highly saline brine with high Cl/Br and Na/Br ratios (Cl/Brmolar 700–13 000 and Na/Brmolar 700–11 000) generated after dissolution of Triassic age evaporites. LA‐ICP‐MS analyses of fluid inclusions in fluorite reveal higher Zn, Pb and Ba contents in the high‐salinity fluids (160–500, 90–170, 320–480 p.p.m. respectively) than in the low‐salinity fluid (75–230, 25–150 and 100–300 p.p.m. respectively). The metal content of the fluids appears to decrease from E to W, from Berbes to La Collada and to Villabona. The source of F is probably related to leaching of volcanic rocks of Permian age. Brines circulated along faults into the Palaeozoic basement. Evaporated sea water was present in permeable rocks and faults along or above the unconformity between the Permo‐Triassic sediments and the Palaeozoic basement. Mineralization formed when the deep brines mixed with the surficial fluids in carbonates, breccias and fractures resulting in the formation of veins and stratabound bodies of fluorite, barite, calcite, dolomite and quartz and minor amounts of sulphides. Fluid movement and mineralization occurred between Late Triassic and Late Jurassic times, probably associated with rifting events related to the opening of the Atlantic Ocean. This model is also consistent with the geodynamic setting of other fluorite‐rich districts in Europe.  相似文献   
989.
Petroleum-bearing fluid inclusions emit fluorescent light when excited with UV or visible light. The fluorescence decay time of the emission is dependent upon the wavelengths of the excitation and emission light, and the chemical composition of the petroleum oil. In general heavy oils have short lifetimes, whereas the emission from light oils is much longer lived. One can thus use plots of the fluorescence lifetime versus emission wavelength ( τ – λ plots), to show even subtle changes in the chemical composition of the entrapped oil. As a consequence, these τ – λ plots can be used for fluid inclusion research to discriminate different oil populations in situ . In particular, it is demonstrated that τ – λ plots discriminate two sets of inclusion oils in each of four North Atlantic basins [Jeanne d'Arc Basin (Newfoundland), Porcupine Basin (Ireland), Clair field West of Shetland (UK) and Kangerlussuaq Basin (East Greenland)] where multistage oil charge is inferred from other geological evidence.  相似文献   
990.
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