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Zusammenfassung Unsere Alltagssprache ist nur zur Beschreibung von Phänomenen, welche im menschlichen Wahrnehmungsbereich der Gleichzeitigkeit liegen, geeignet. Die Diskussion von Begriffen, wie z. B. Kausalität und Zufall, erfordert eine sprachlichea-priori-Begrenzung der Signalfortbewegung (Wilkinson). Eine solche neue Sprache muss auch informationstheoretische Konzepte enthalten. 相似文献
124.
E. Fischer H. Spatz B. Heller H. Reggiani 《Cellular and molecular life sciences : CMLS》1972,28(3):307-308
Zusammenfassung Nachweis, dass die Phenethylamin-ausscheidung bei endogener, nicht aber bei sekundär atypischer Depression signifikativ vermindert, bei Manie und Schizophrenie aber entsprechend erhöht ist. Die Behandlung der endogenen, nicht aber der sekundären Depression mit trizyklischen antidepressiven Mitteln erhöht die Phenethylaminausscheidung. Der Phenethylamingehalt im Rattengehirn wird durch Reserpin signifikant vermindert, durch Iproniazid, Imipramin und Chlorimipramin jedoch signifikant erhöht. 相似文献
125.
Zusammenfassung Der genetisch kontrollierte, hohe Geschmacksschwellenwert — Geschmacksblindheit — gegenüber Phenylthioharnstoff (PTC) und anderen bitteren, strukturell ähnlichen Anti-Schilddrüsensubstanzen, scheint durch die Qualität und Quantität des löslichen Speichel-Enzym-Systems Tyrosiniodinase bedingt zu sein.PTC-Geschmacksblinde sind «Alles-Esser», PTC-Schmecker hingegen weisen eine erhöhte kulinarische Selektivität auf. Diese Tatsache ist um so interessanter, als der Schwellenwert der beiden Gruppen gegenüber den klassischen Geschmacksqualitäten — süss, salzig, sauer und bitter — derselbe ist. 相似文献
126.
R. Fischer 《Cellular and molecular life sciences : CMLS》1955,11(4):162-163
Zusammenfassung Die Hypothese einer Biosynthese vond-Lysergsäure-diäthylamidähnlichen Substanzen aus Meskalin in der Leber und im Gehirn wird postuliert. 相似文献
127.
Brunet M Guy F Pilbeam D Mackaye HT Likius A Ahounta D Beauvilain A Blondel C Bocherens H Boisserie JR De Bonis L Coppens Y Dejax J Denys C Duringer P Eisenmann V Fanone G Fronty P Geraads D Lehmann T Lihoreau F Louchart A Mahamat A Merceron G Mouchelin G Otero O Pelaez Campomanes P Ponce De Leon M Rage JC Sapanet M Schuster M Sudre J Tassy P Valentin X Vignaud P Viriot L Zazzo A Zollikofer C 《Nature》2002,418(6894):145-151
The search for the earliest fossil evidence of the human lineage has been concentrated in East Africa. Here we report the discovery of six hominid specimens from Chad, central Africa, 2,500 km from the East African Rift Valley. The fossils include a nearly complete cranium and fragmentary lower jaws. The associated fauna suggest the fossils are between 6 and 7 million years old. The fossils display a unique mosaic of primitive and derived characters, and constitute a new genus and species of hominid. The distance from the Rift Valley, and the great antiquity of the fossils, suggest that the earliest members of the hominid clade were more widely distributed than has been thought, and that the divergence between the human and chimpanzee lineages was earlier than indicated by most molecular studies. 相似文献
128.
Holzenberger M Dupont J Ducos B Leneuve P Géloën A Even PC Cervera P Le Bouc Y 《Nature》2003,421(6919):182-187
Studies in invertebrates have led to the identification of a number of genes that regulate lifespan, some of which encode components of the insulin or insulin-like signalling pathways. Examples include the related tyrosine kinase receptors InR (Drosophila melanogaster) and DAF-2 (Caenorhabditis elegans) that are homologues of the mammalian insulin-like growth factor type 1 receptor (IGF-1R). To investigate whether IGF-1R also controls longevity in mammals, we inactivated the IGF-1R gene in mice (Igf1r). Here, using heterozygous knockout mice because null mutants are not viable, we report that Igf1r(+/-) mice live on average 26% longer than their wild-type littermates (P < 0.02). Female Igf1r(+/-) mice live 33% longer than wild-type females (P < 0.001), whereas the equivalent male mice show an increase in lifespan of 16%, which is not statistically significant. Long-lived Igf1r(+/-) mice do not develop dwarfism, their energy metabolism is normal, and their nutrient uptake, physical activity, fertility and reproduction are unaffected. The Igf1r(+/-) mice display greater resistance to oxidative stress, a known determinant of ageing. These results indicate that the IGF-1 receptor may be a central regulator of mammalian lifespan. 相似文献
129.
To understand the physical processes that occur in nature we need to obtain a solid concept about the 'fundamental' forces acting between pairs of elementary particles. It is also necessary to describe the temporal and spatial evolution of many mutually interacting particles under the influence of these forces. This latter step, known as the few-body problem, remains an important unsolved problem in physics. Experiments involving atomic collisions represent a useful testing ground for studying the few-body problem. For the single ionization of a helium atom by charged particle impact, kinematically complete experiments have been performed since 1969 (ref. 7). The theoretical analysis of such experiments was thought to yield a complete picture of the basic features of the collision process, at least for large collision energies. These conclusions are, however, almost exclusively based on studies of restricted electron-emission geometries. Here, we report three-dimensional images of the complete electron emission pattern for the single ionization of helium by the impact of C6+ ions of energy 100 MeV per a.m.u. (a four-body system) and observe features that have not been predicted by any published theoretical model. We propose a higher-order ionization mechanism, involving the interaction between the projectile and the target nucleus, to explain these features. 相似文献
130.
The tumour suppressor CYLD negatively regulates NF-kappaB signalling by deubiquitination 总被引:1,自引:0,他引:1
Kovalenko A Chable-Bessia C Cantarella G Israël A Wallach D Courtois G 《Nature》2003,424(6950):801-805