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181.
Zusammenfassung Äthylenglykol-dimethansulfonat (EDS) wird von der Ratte zu N-Acetyl-S-(-hydroxyäthyl)-cystein (V), N-Acetyl-S-(-hydroxyäthyl)-cystein-S-oxyd (VI), und Methansulfonsäure abgebaut. Äthylendibromid (EDB) gibt ausser V und VI, S-(-Hydroxyäthyl)-cystein (III) und wird weiter zu Kohlendioxyd und anorganischem Sulphat via S-(-Hydroxyäthyl)-cystein-S-oxyd (IV) abgebaut. Keine der erwähnten Stoffwechselprodukte sind gegen Tumoren oder gegen Spermatogenese wirksam.
This work was supported by grants from the Ford Foundation and the Wellcome Trust (A. R. J.) and the British Empire Cancer Campaign for Research (K. E.). 相似文献
This work was supported by grants from the Ford Foundation and the Wellcome Trust (A. R. J.) and the British Empire Cancer Campaign for Research (K. E.). 相似文献
182.
183.
Ohne Zusammenfassung
Vorgelegt von
M. Kline
The work of H. Edwards was supported by part by the U. S. National Science Foundation Grant SOC-7905162 and by the Vaughn Foundation. 相似文献
184.
Long-term trend and abrupt events of the Holocene Asian monsoon inferred from a stalagmite δ18O record from Shennongjia in Central China 总被引:13,自引:0,他引:13
SHAO Xiaohua WANG Yongjin CHENG Hai KONG Xinggong WU Jiangying EDWARDS R. Lawrence 《科学通报(英文版)》2006,51(2):221-228
The middle-Holocene was a period of profound cul- ture transitions: the Neolithic culture around Central China[1], Mesopotamia[2] and India[3] all mysteriously collapsed around 4 ka . It is plausible that this civiliza-tion collapse can be contributed to … 相似文献
185.
Walter RC Buffler RT Bruggemann JH Guillaume MM Berhe SM Negassi B Libsekal Y Cheng H Edwards RL von Cosel R Néraudeau D Gagnon M 《Nature》2000,405(6782):65-69
The geographical origin of modern humans is the subject of ongoing scientific debate. The 'multiregional evolution' hypothesis argues that modern humans evolved semi-independently in Europe, Asia and Africa between 100,000 and 40,000 years ago, whereas the 'out of Africa' hypothesis contends that modern humans evolved in Africa between 200 and 100 kyr ago, migrating to Eurasia at some later time. Direct palaeontological, archaeological and biological evidence is necessary to resolve this debate. Here we report the discovery of early Middle Stone Age artefacts in an emerged reef terrace on the Red Sea coast of Eritrea, which we date to the last interglacial (about 125 kyr ago) using U-Th mass spectrometry techniques on fossil corals. The geological setting of these artefacts shows that early humans occupied coastal areas and exploited near-shore marine food resources in East Africa by this time. Together with similar, tentatively dated discoveries from South Africa this is the earliest well-dated evidence for human adaptation to a coastal marine environment, heralding an expansion in the range and complexity of human behaviour from one end of Africa to the other. This new, wide-spread adaptive strategy may, in part, signal the onset of modern human behaviour, which supports an African origin for modern humans by 125 kyr ago. 相似文献
186.
Keane TM Goodstadt L Danecek P White MA Wong K Yalcin B Heger A Agam A Slater G Goodson M Furlotte NA Eskin E Nellåker C Whitley H Cleak J Janowitz D Hernandez-Pliego P Edwards A Belgard TG Oliver PL McIntyre RE Bhomra A Nicod J Gan X Yuan W van der Weyden L Steward CA Bala S Stalker J Mott R Durbin R Jackson IJ Czechanski A Guerra-Assunção JA Donahue LR Reinholdt LG Payseur BA Ponting CP Birney E Flint J Adams DJ 《Nature》2011,477(7364):289-294
187.
Dinsdale EA Edwards RA Hall D Angly F Breitbart M Brulc JM Furlan M Desnues C Haynes M Li L McDaniel L Moran MA Nelson KE Nilsson C Olson R Paul J Brito BR Ruan Y Swan BK Stevens R Valentine DL Thurber RV Wegley L White BA Rohwer F 《Nature》2008,452(7187):629-632
Microbial activities shape the biogeochemistry of the planet and macroorganism health. Determining the metabolic processes performed by microbes is important both for understanding and for manipulating ecosystems (for example, disruption of key processes that lead to disease, conservation of environmental services, and so on). Describing microbial function is hampered by the inability to culture most microbes and by high levels of genomic plasticity. Metagenomic approaches analyse microbial communities to determine the metabolic processes that are important for growth and survival in any given environment. Here we conduct a metagenomic comparison of almost 15 million sequences from 45 distinct microbiomes and, for the first time, 42 distinct viromes and show that there are strongly discriminatory metabolic profiles across environments. Most of the functional diversity was maintained in all of the communities, but the relative occurrence of metabolisms varied, and the differences between metagenomes predicted the biogeochemical conditions of each environment. The magnitude of the microbial metabolic capabilities encoded by the viromes was extensive, suggesting that they serve as a repository for storing and sharing genes among their microbial hosts and influence global evolutionary and metabolic processes. 相似文献
188.
Microfluidic diagnostic technologies for global public health 总被引:2,自引:0,他引:2
The developing world does not have access to many of the best medical diagnostic technologies; they were designed for air-conditioned laboratories, refrigerated storage of chemicals, a constant supply of calibrators and reagents, stable electrical power, highly trained personnel and rapid transportation of samples. Microfluidic systems allow miniaturization and integration of complex functions, which could move sophisticated diagnostic tools out of the developed-world laboratory. These systems must be inexpensive, but also accurate, reliable, rugged and well suited to the medical and social contexts of the developing world. 相似文献