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11.
The use of height data to measure living standards is now a well-established method in the economic history literature. Moreover, a number of core findings are widely agreed upon. There are still some populations, places, and times, however, for which anthropometric evidence remains limited. One such example is 19th century African-Americans in the Northern US. Here, we use new data from the Ohio state prison to track heights of Black and White men incarcerated between 1829 and 1913. We corroborate the well-known mid-century height decline among White men. We find that Black men were shorter than White men, throughout the century controlling for a number of characteristics. We also find a pattern of height decline among Black men in mid-century similar to that found for White men.  相似文献   
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All the sources of records of the serin (Serinus serinus) in 16th century Europe are (re-)examined, both those already known and some that have been newly discovered. Interpretation of this more detailed information confirms the results which were published by Ernst Mayr in 1926 in his doctoral thesis: north of 48°N there were no free-living populations of Serinus serinus in the 16th century. All 11 localities identified refer to captive birds or to specimens in the bird trade, the origins of which can be convincingly traced. However, free-living populations are recorded from Carinthia (Austria), Trentino (Italy), Ticino (Switzerland), Provence and Gascony (France). An occurrence in the Swiss Jura (Bötzberg), and indications that it was present throughout the whole Tyrol and the Rhône Valley, suggest that the serin had already begun to expand its range, but was halted by colder periods of the Little Ice Age after 1585, only resuming a rapid expansion at the beginning of the 19th century. The zoogeographic situation suggests that the western and eastern parts of the Central European population have a separate history of immigration. Their possible heterogeneity and subsequent fusion urgently require a genetic investigation.Communicated by F. Bairlein  相似文献   
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The circumstances surrounding the first study of human growth, published in 1754, are described. Jampert, who made this study, died young and his work was not recognised, indeed remained completely unknown between 1778 and 1981. The content of the work is briefly described.  相似文献   
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The purpose of our study was to summarize the knowledge on exfoliative cytology during the 19th century and to track down Papanicolaou's predecessors. A thorough study of texts, medical books and reports, together with a review of the available literature in PubMed, was undertaken. The study of cytological preparations as a diagnostic procedure can be traced back to the work of the famous French microscopist Alfred François Donné. However, the systematic study and the criteria for the diagnosis of malignant cells should be attributed to Johannes Müller. The increasing interest in the cytological examination of various fluids of the human body can be confirmed by a plethora of studies published during this period. By the end of the 19th century, the invention of new techniques in pathology, such as the introduction of cell block techniques, tissue sections and new staining methods which provided the opportunity to study surgical specimens in three dimensions, led to a decrease in the interest in exfoliative cytology, which was re‐discovered by George Papanicolaou almost three decades later.  相似文献   
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Soil texture plays a key role in belowground C storage in forest ecosystems and strongly influences nutrient availability and retention, particularly in highly weathered soils. We used field data and the Century ecosystem model to explore the role of soil texture in belowground C storage, nutrient pool sizes, and N fluxes in highly weathered soils in an Amazonian forest ecosystem. Our field results showed that sandy soils stored approximately 113 Mg C ha-1 to a 1-m depth versus 101 Mg C ha-1 in clay soils. Coarse root C represented a large and significant ecosystem C pool, amounting to 62% and 48% of the surface soil C pool on sands and clays, respectively, and 34% and 22% of the soil C pool on sands and clays to 1-m depth. The quantity of labile soil P, the soil C:N ratio, and live and dead fine root biomass in the 0–10-cm soil depth decreased along a gradient from sands to clays, whereas the opposite trend was observed for total P, mineral N, potential N mineralization, and denitrification enzyme activity. The Century model was able to predict the observed trends in surface soil C and N in loams and sands but underestimated C and N pools in the sands by approximately 45%. The model predicted that total belowground C (0–20 cm depth) in sands would be approximately half that of the clays, in contrast to the 89% we measured. This discrepancy is likely to be due to an underestimation of the role of belowground C allocation with low litter quality in sands, as well as an overestimation of the role of physical C protection by clays in this ecosystem. Changes in P and water availability had little effect on model outputs, whereas adding N greatly increased soil organic matter pools and productivity, illustrating the need for further integration of model structure and tropical forest biogeochemical cycling. Received 3 March 1999; accepted 27 August 1999.  相似文献   
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展望21世纪的生命科学   总被引:17,自引:0,他引:17  
李宝健 《生命科学》2000,12(1):37-40,43
对本世纪以来发展迅猛异常的生物科学的概况,特别是近对二三十年来,在分子生物学的带动下,生命科学在结构分子生物学;中心法则及其后的生物学细节研究;基因表达、调控和发育生物学;基因组计划和应用生物学及生物技术的发展;宏观生物学等方面讨论了生命科学的发展和特点,并从四个主要方面对21世纪生命科学(包括生物技术)的发展趋势进行了预测,以达到综览生命科学全局,明确今后发展方向的目的。  相似文献   
18.
Ethnic affiliations and divisions have come to pose serious challenges to the strengthening of civil society and the quest for nationhood in Africa. While ethnicity was employed by the colonial state to divide the colony and weaken the nationalist movements, post‐colonial regimes and governments have manipulated ethnic differences to consolidate their control over society and promote exploitative relations of power, production and exchange. The limited hegemony of the post‐colonial state, its inability to meet the basic needs of the vast majority, and its heavy reliance on violence and coercion to maintain control, make it very ‘irrelevant’ to the existential conditions of the vast majority. While ethnic identities continue to pose challenges to efforts at growth, development and political stability, largely because the masses have increasingly identified with primordial institutions in the absence of a democratic and strong state, current conditions of debt, drought, poverty, inflation and other pains imposed by the structural adjustment programmes will continue to weaken the state and strengthen the relevance of ethnic associations and identities. The opening up of the political processes, emphasis on the politics of consensus and accommodation, the democratization of society and empowerment of mass‐based organizations remain the only ways to contain the divisive influences of ethnic politics and identities in Africa.  相似文献   
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“Alpha behavior” affected human politics and social organization during the sixteenth-century conquest of Mexico by Spanish imperialists. The behavior of Spanish conquistadores is compared to that of other primates in the well-known studies of Jane Goodall and Frans de Waal. Parallels between Spanish and Aztec behavior are also noted so as to identify the shared patterns of behavior that cross human cultures and may be called primate universals. One of these universals is the alpha factor. It administers the social order through the ability to balance benevolence and brutality in order to maintain coalitions and the loyalty of subordinates. The alpha factor is expressed through display behaviors that vary with culture, but all cultures, including those of chimpanzees and bonobos, build around it. It may be tempered by the presence of female coalitions or of a bonobo alpha female, but it is a visible focal point of a society, thereby making display a necessary part of leadership.  相似文献   
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