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61.
Chr Rosenthal 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1965,34(8):316-324
Ohne ZusammenfassungMit 4 Abbildungen 相似文献
62.
Chr Deichler und O. Kleinschmidt 《Journal of Ornithology》1896,44(4):416-483
Ohne Zusammenfassung 相似文献
63.
Katharina M. Katsaros Walter S Speidl Svitlana Demyanets Stefan P. Kastl Konstantin A. Krychtiuk Anna Wonnerth Gerlinde Zorn Ioannis Tentzeris Serdar Farhan Gerald Maurer Johann Wojta Kurt Huber 《PloS one》2015,10(11)
Granulocyte-colony-stimulating-factor (G-CSF) induces mobilization of progenitor cells but may also exert pro-inflammatory and pro-thrombotic effects. Treatment with recombinant G-CSF after acute myocardial infarction is currently under examination and has been associated with in-stent restenosis. However, it is not known whether plasma levels of endogenous G-CSF are also associated with an increased cardiovascular risk. Therefore we included 280 patients with angiographically proven stable coronary artery disease. G-CSF was measured by specific ELISA and patients were followed for a median of 30 months for the occurrence of major adverse cardiovascular events (MACE: death, myocardial infarction, re-hospitalization). Those with cardiac events during follow-up showed significant higher G-CSF levels (32.3 pg/mL IQR 21.4–40.5 pg/mL vs. 24.6 pg/mL IQR 16.4–34.9 pg/mL; p<0.05) at baseline. Patients with G-CSF plasma levels above the median had a 2-fold increased risk for MACE (p<0.05). This was independent from established cardiovascular risk factors. In addition, G-CSF above the median was a predictor of clinical in-stent restenosis after implantation of bare-metal stents (6.6% vs. 19.4%; p<0.05) but not of drug-eluting stents (7.7% vs. 7.6%; p = 0.98). This data suggests that endogenous plasma levels of G-CSF predict cardiovascular events independently from established cardiac risk factors and are associated with increased in-stent restenosis rates after implantation of bare metal stents. 相似文献
64.
Chr Jordan R. V. Sengbusch 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1957,27(4):186-187
Ohne ZusammenfassungMit 2 TextabbildungenDiese Arbeit wurde mit Unterstützung der Deutschen Forschungsgemeinschaft durchgeführt. 相似文献
65.
Nils Chr. Stenseth 《Theoretical population biology》1986,29(3):365-384
Mathematical models are developed in order to analyze whether or not social factors, such as, for example, the “social fence” (J. B. Hestbeck, 1982, Oikos 39, 157–163) will stabilize population density: the dynamic interaction between social factors and (dynamic) trophic factors is analyzed. It is concluded that social factors such as the “social fence” tend to stabilize population density; hence, if density cycles (as, e.g., seen in many microtine rodents) are observed in nature, it seems reasonable to conclude that density cycles are driven by, for example, trophic interactions and not by social factors. It is suggested that the “social fence” may explain why so many populations including several microtine populations have fairly stable densities despite the ever-existing destabilizing trophic interactions. Contrary to what is implied by J. B. Hestbeck (1983, “A Mathematical Model of Population Regulation in Cyclic Mammals,” Lecture notes in biomathematics, Vol. 52, Springer-Verlag, Berlin/New York), the analysis presented in this paper demonstrates that seasonal environmental changes are not essential for the generation of regular density cycles. Seasonal changes may, however, be necessary for generating a microtine-like density cycle. Empirical information on microtine rodents relating to the “social fence hypothesis” is discussed. 相似文献
66.
Mougin, J.-L., Granadeiro, J. P., Jouanin, C. & Roux, F. 1999. Philopatry and faithfulness to nest site in Cory's Shearwaters Calonectris diomedea at Selvagem Grande. Ostrich 70 (3&4): 229–232. Nearly fledged Cory's Shearwater Calonectris diomedea chicks at Selvagem Grande occasionally desert their nest sites during the night, but generally return before dawn. The temporary use of other nest sites is rare and lasts less than two days. Almost all chicks from Selvagem Grande return to the island for their first breeding attempt; very few breed at islands outside the archipelago. On Selvagem Grande, almost half the males return to their native colony whereas more than 90% of females recruit to other colonies. Inter-colony movements sometimes exceed 1 km, but, if they return to their native colony, both sexes settle within 20 m of their natal site. From the second breeding attempt onwards, most birds of both sexes are faithful to the nest site. On average, less than 20% of birds desert their former nest site each year, with a shift of about 4 m only. Most nest shifts follow a breeding failure or a temporary respite from breeding, and are accompanied by a switch in partners. Mougin, J.-L., Granadeiro, J. P. Jouanin, C. & Roux, F. 1999. Philopatrie et fidélité au nid chez le Puffin cendré Calonectris diomedea de Selvagem Grande. Ostrich 70 (3&4): 229–232. Le poussin en fin de croissance du Puffin cendré Calonectris diomedea de Selvagem Grande déserte parfois son nid pendant la nuit, mais y revient généralement avant le jour. L'utilisation temporaire d'un autre site de nid est rare et dure moins de deux jours. Les jeunes adultes nés à Selvagem Grande reviennent presque toujours nicher sur l'île et extrêmement rarement en dehors de l'archipel. A Selvagem Grande, près de la moitié des mâles reviennent à leur colonie de naissance, mais moins de 10% des femelles. Le déplacement est parfois supérieur à 1 km mais, s'ils reviennent à leur colonie natale, les deux sexes s'établissent à moins de 20 m du nid où ils sont nés. A partir de leur deuxième reproduction, les deux sexes sont fidèles à leur nid. Moins de 20% des oiseaux changent de nid d'une année à l'autre, avec un déplacement de 4 m seulement, le plus souvent à la suite d'un échec ou d'une interruption temporaire de la reproduction, ce déplacement étant le plus souvent accompagne d'un changement de partenaire. 相似文献
67.
Activation of Ca2+-dependent processes during heat shock: role in cell thermoresistance 总被引:5,自引:0,他引:5
In this brief review, it is proposed that some Ca2+-dependent processes are induced upon subjecting cells to hyperthermic temperature, and play an essential role in the final cell responses. The triggering signal does not involve external Ca2+. Instead, it is most likely to be generated by a redistribution of Ca2+ between the internal pools. A role for heat-induced Ca2+-dependent processes is supported by findings that Ca2+-active agents such as chelators, ionophores, or anticalmodulin drugs modify the cytotoxic action of hyperthermia and that some heat shock proteins are calmodulin-binding proteins. Furthermore, within minutes at hyperthermic temperature, changes are observed in the pattern of phosphoproteins suggesting that heat shock activates kinase or phosphatase activities, processes which are often mediated by Ca2+. Suggestive evidence that these phosphorylation events are determinants of cell thermoresistance is provided by the fact that one of these proteins whose phosphorylation changes rapidly upon hyperthermia is a heat shock protein (HSP28) and that the content of HSP28 is elevated not only in thermotolerant cells but also in a family of thermoresistant variants isolated after mutagenesis of Chinese hamster cells. 相似文献
68.
Gerodontology 2011; doi: 10.1111/j.1741‐2358.2010.00382.x Partial edentulism and removable partial denture design in a dental school population: a survey in Greece Objectives: To investigate the pattern of partial edentulism and the most frequent designs of cobalt‐chromium removable partial dentures (RPDs), constructed at the Dental School of Athens, Greece. Methods and materials: Five hundred and fifty‐three patients, between 42 and 81 years old, mostly males, treated by undergraduate dental students, were included. The survey was based on visual evaluation of master casts and work authorisation to dental technicians. Aspects examined were: Kennedy Classification, modification areas, major connectors, clasping, placement of rest seats and indirect retention. Results: Kennedy Class I was the most common encountered in the maxilla (50.5%) and in the mandible (70%). The most frequent major connectors were the lingual bar (92.6%) and the U‐shaped palatal strap (54%). The most common clasp was the Roach (69.2%) in Class I and Class II. In Class III and IV, the most common was the occlusally approaching clasp (55% and 70%). The most frequent location of the rest was mesial of abutment teeth. On the average, 39.5% of Class I RPDs and 58.6% of Class II RPDs had indirect retainers. Conclusion: A combination of the two major philosophies of RPD design (biomechanical and hygienic) was evident in the RPDs examined in our study. 相似文献
69.
Fragmentation of bovine chromogranin A by plasma kallikrein 总被引:1,自引:0,他引:1
Chromogranin A has been reported to be processed in vivo by an as yet undefined proteinase(s) suggesting that it is a precursor of biologically active peptides such as pancreastatin. In this study, plasma kallikrein was used as a model proteinase to identify the cleavage sites exposed in bovine parathyroid chromogranin A. Purified bovine parathyroid chromogranin A was digested with human plasma kallikrein. The proteolytic fragments produced were isolated by HPLC and chemically characterized by amino acid composition and sequence analysis. The combined results indicate that the enzyme has preference for specific single Arg residues, cutting C-terminal to this amino acid, although certain pairs of basic sites were also cleaved. The characterized fragments were released in a selective manner from the whole molecule with rapid production of the fragments covering positions 1-247 and 352-358. 相似文献
70.
The structure of alpha-melanocyte-stimulating hormone (alpha-MSH) has been determined in the pars intermedia of the frog Rana ridibunda. Pulse-chase labeling of frog neurointermediate lobes with selective amino acids revealed that the composition of frog alpha-MSH is similar to that of alpha-MSH from all mammalian species yet studied. Tryptic mapping of nexly synthetized alpha-MSH generated two fragments with the following amino acid composition: (T1) Trp, Pro, Lys, Gly, Val and (T2) Tyr, Arg, Phe, His, Ser, Glu. Concurrently, alpha-MSH was purified from 100 neurointermediate lobes to apparent homogeneity by reverse-phase HPLC. The sequence of the peptide determined by automated Edman degradation was Ser-Tyr-Ser-Met-Glu-His-Phe-Arg-Trp-Gly-Lys-Pro-Val. The structure of frog alpha-MSH is thus identical to mammalian des-N alpha-acetyl alpha-MSH and differs from the sequence of toad (Xenopus laevis) alpha-MSH only by the first residue (Ser instead of Ala). These results confirm that the sequence of alpha-MSH has been highly preserved during evolution. 相似文献