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211.
Johannes Salamon Tatjana Hoffmann Eva Elies Kersten Peldschus Julia S. Johansen Georg Lüers Udo Schumacher Daniel Wicklein 《PloS one》2014,9(4)
Induced overexpression of the secretory protein YKL-40 promotes tumor growth in xenograft experiments. We investigated if targeting YKL-40 with a monoclonal antibody could inhibit tumor growth. YKL-40 expressing human melanoma cells (LOX) were injected subcutenously in Balb/c scid mice. Animals were treated with intraperitoneal injections of anti-YKL-40, isoptype control or PBS. Non-YKL-40 expressing human pancreatic carcinoma cell line PaCa 5061 served as additional control. MR imaging was used for evaluation of tumor growth. Two days after the first injections of anti-YKL-40, tumor volume had increased significantly compared with controls, whereas no effects were observed for control tumors from PaCa 5061 cells lacking YKL-40 expression. After 18 days, mean tumor size of the mice receiving repeated anti-YKL-40 injections was 1.82 g, >4 times higher than mean tumor size of the controls (0.42 g). The effect of anti-YKL-40 on the increase of tumor volume started within hours after injection and was dose dependent. Intratumoral hemorrhage was observed in the treated animals. The strong effect on tumor size indicates important roles for YKL-40 in melanoma growth and argues for a careful evaluation of antibody therapy directed against YKL-40. 相似文献
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Insects and spiders were sampled on branches of spruce in a 5.5 km2 area before and after each of six winters. Psocoptera, Aphidoidea and Lepidoptera larvae were the most common insects in autumn. In Feb–Mar only 1% remained, most of the decline occurring already early in the winter. Spiders were almost as common as Psocoptera in autumn but survived winter to 28–45%. Spiders therefore are potentially more important food for wintering birds than are insects. Through the first five winters there was a steady increase in density of small (but not large) spiders both in autumn (290%) and spring (390%). Spring densities of small but not large spiders were significantly correlated to autumn densities. Usually there was no added variability of spider abundance between trees and most of the variability was found within trees. In autumn spiders occurred at significantly higher densities in the lower half of the spruce trees than in the upper half. Much of the reduction of large spiders over winter is known to be caused by predation by birds. Over winter, this predation probably makes the distribution of spiders within trees more uniform. The autumn density of three tit species, the goldcrest and the treecreeper was significantly correlated with the density of large spiders at the same time, but not with small spiders (which they presumably do not eat). This might be caused by territorial behaviour being related to food density in autumn. 相似文献
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Johan Svenson 《Phytochemistry Reviews》2013,12(3):567-578
The deep waters surrounding the coastline of the northern parts of Norway represent an exciting biotope for marine exploration. Dark and cold Arctic water generates a hostile environment where the ability to adapt is crucial to survival. These waters are nonetheless bountiful and a diverse plethora of marine organisms thrive in these extreme conditions, many with the help of specialised chemical compounds. In comparison to warmer, perhaps more inviting shallower tropical waters, the Arctic region has not been as thoroughly investigated. MabCent is a Norwegian initiative based in Tromsø that aims to change this. Since 2007, scientists within MabCent have focussed their efforts on the study of marine organisms inhabiting the Arctic waters with the long term goal of novel drug discovery and development. The activities of MabCent are diverse and range from sampling the Arctic ice shelf to the chemical synthesis of promising secondary metabolites discovered during the screening process. The current review will present the MabCent pipeline from isolation to identification of new bioactive marine compounds via an extensive screening process. An overview of the main activities will be given with particular focus on isolation strategies, bioactivity screening and structure determination. Pitfalls, hard earned lessons and the results so far are also discussed. 相似文献
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H. Lüers 《Molecular & general genetics : MGG》1938,74(1):70-90
Ohne ZusammenfassungMit 1 Figur und 5 Tabellen 相似文献
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Mats Forsman Anna Nyrén ers Sjöstedt Lilian Sjökvist Gunnar Sandström 《FEMS microbiology ecology》1995,16(1):83-92
Abstract Francisella tularensis , the causative agent of the epizootic disease tularemia in mammals, can be isolated from mud and water. To study the spread and persistence of Francisella tularensis in water, different strategies for pre-treatment of natural water samples prior to identification of the bacterium by polymerase chain reaction (PCR) were evaluated. A method for handling of samples taken from natural waters was developed. Applied on natural water samples amended with F. tularensis , the method rendered identification by PCR reproducible and it resulted in an amplified Francisella -specific product in all samples from natural waters tested. In addition, by employing primers targeting conserved regions of the 16S rDNA the presence of bacteria was demonstrated in all samples investigated. The results presented will, in combination with other techniques that allow identification, improve studies on the epizootiology and epidemiology of the genus Francisella . 相似文献