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991.
Linda C. McCarthy Marie-Therese Bihoreau Susanna L. Kiguwa Julie Browne Takeshi K. Watanabe Haretsugu Hishigaki Atsushi Tsuji Susanne Kiel Caleb Webber Maria E. Davis Catherine Knights Angela Smith Ricky Critcher Patrick Huxtall James R. Hudson Jr. Toshihide Ono Hiroumi Hayashi Toshihisa Takagi Yusuke Nakamura Akira Tanigami Peter N. Goodfellow G. Mark Lathrop Michael R. James 《Mammalian genome》2000,11(9):791-795
992.
Diversity of Bacterial Endosymbionts of Environmental Acanthamoeba Isolates 总被引:1,自引:0,他引:1 下载免费PDF全文
Stephan Schmitz-Esser Elena R. Toenshoff Susanne Haider Eva Heinz Verena M. Hoenninger Michael Wagner Matthias Horn 《Applied microbiology》2008,74(18):5822-5831
Free-living amoebae are frequent hosts for bacterial endosymbionts. In this study, the symbionts of eight novel environmental Acanthamoeba strains isolated from different locations worldwide were characterized. Phylogenetic analysis revealed that they were related to one of four evolutionary lineages of amoeba symbionts recognized previously. This study provides evidence for the existence of only a small number of phylogenetically well-separated groups of obligate intracellular endosymbionts of acanthamoebae with global distribution. 相似文献
993.
Repeated applications of Cydia pomonella granulovirus (CpGV) can effectively control the codling moth (CM) in apple orchards. However, it is still unknown whether horizontal transmission of the virus from infected to uninfected larvae contributes to the efficacy of the virus insecticide. Horizontal transmission of CpGV was assayed using detached apples. In experiments using artificially applied virus dots on the apple’s surface or infected CM larvae as virus inoculum, it was found that the likelihood of infection of healthy CM larvae relied mainly on the larval behavior. The amount of virus inoculum, either applied artificially or produced by the infected larvae, impacted the infection rate only to a small degree. In the experiments, CM larvae exhibited a strong preference in entry sites, increasing the chance for horizontal transmission. Depending on the experimental design, horizontal transmission rates of about 40% were observed in laboratory assays. 相似文献
994.
995.
The flagellate Euglena gracilis Klebs strain Z shows phototaxis and changes cell shape between oblong and round. Both cell events show daily rhythmicity. Phototaxis was highest about 2 h after light onset with a second peak of activity 9 h later. At the same times, the cells were in their most oblong shape. During the night phase the cells were phototactically inactive and round. These rhythms were altered by environmental stress, e.g. UV-B radiation (280–320 nm) and nitrogen deficiency. Artificial UV-B radiation of 0.5 W m−2 caused a loss in phototaxis hut the peak of activity occurred at the same time as for control cells. The transition from round to oblong cell shape was slower after UV-B radiation, but the difference between the roundest and the most oblong cell shape was unchanged. Nitrogen deficiency caused a total loss of phototaxis and the cells remained round all the time. The cells lost all their chlorophyll and were, therefore, photosynthetically inactive. 相似文献
996.
997.
Harald Carlsen Fred Haugen Susanne Zadelaar Robert Kleemann Teake Kooistra Christian A. Drevon Rune Blomhoff 《Genes & nutrition》2009,4(3):215-222
The nuclear factor (NF)-κB is a primary regulator of inflammatory responses and may be linked to pathology associated with obesity. We investigated the progression of NF-κB activity during a 12-week feeding period on a high-fat diet (HFD) or a low-fat diet (LFD) using NF-κB luciferase reporter mice. In vivo imaging of luciferase activity showed that NF-κB activity was higher in the HFD mice compared with LFD-fed mice. Thorax region of HFD females displayed fourfold higher activity compared with LFD females, while no such increase was evident in males. In male HFD mice, abdominal NF-κB activity was increased twofold compared with the LFD males, while females had unchanged NF-κB activity in the abdomen by HFD. HFD males, but not females, exhibited evident glucose intolerance during the study. In conclusion, HFD increased NF-κB activity in both female and male mice. However, HFD differentially increased activity in males and females. The moderate increase in abdomen of male mice may be linked to glucose intolerance. 相似文献
998.
Roland Dürr Reiner Hegerl Susanne Volker Ute Santarius Wolfgang Baumeister 《Journal of structural biology》1991,106(3)
The three-dimensional structure of the surface layer protein of the hyperthermophilic archaebacterium Pyrodictium brockii was determined by electron crystallographic techniques to a resolution of approximately 1.6 nm. Two image processing strategies—correlation averaging and lattice unbending—were explored with regard to their potential to compensate for lattice distortions. Reconstructions performed via these two routes did not show any significant difference although the unbending approach might be expected to give superior results since, in principle, it incorporates a correction for unit cell displacement, rotation, and deformation while conventional correlation averaging compensates for displacements only. The discussion furthermore addresses some hitherto ignored problems associated with the correction of lattice disorder at higher tilts. 相似文献
999.
Zusammenfassung Eine Pilotstudie zur Auswilderung des Waldrapps wurde unter Berücksichtigung der Sozialstruktur durchgeführt. Da Waldrappe ihre Jungen bis zur nächsten Brutsaison führen, mußten zwei menschliche Pflegeeltern die Aufzucht- und Führungsrolle übernehmen. Sechs Jungvögel wurden zunächst von Hand aufgezogen und lange vor dem Flüggewerden an den Auflassungsort gebracht. Sie erhielten weitgehend natürliche Nahrung und wurden auch nach dem Ausfliegen von den beiden Pflegepersonen betreut. Somit wurde eine Familienstruktur geschaffen, die den Jungvögeln einerseits ein gefahrloses Erkunden ihrer Umwelt ermöglichte, andererseits eine zu große Zahmheit gegenüber Fremdpersonen verhinderte. In Feindmeidung, Nahrungssuch-Strategien und Nahrungwahl verhielten sie sich wie gleichaltrige Vögel aus Freilandpopulationen. Der positive Ausgang war Vorausbedingung für eine Auswilderung in Südspanien, die nach gleicher Methode ablaufen wird.
Successful introduction of Waldrapp Ibis (Geronticus eremita) on the basis of family bonding — a pilot study in Austria
Summary In 1991, the Alpenzoo Innsbruck/Tirol initiated a pilot study to test a new method for releasing the highly endangered Waldrapp Ibis into its natural habitat based on the complex social system and tight family bonds of this highly social species. Young Waldrapp Ibises have a very close contact with their parents, usually up to the next breeding season. Especially in the first fledgling days the guidance of the parents is indispensable. Six chicks of the colony in the Alpenzoo were handreared to produce parent imprinting. In order to achieve food imprinting the birds were fed to a large extend on insects wich constitute their natural food. Handrearing took place at the releasing station, an adapted farmhouse near Innsbruck. Two human foster parents stayed continuously with the fledglings for six month. The simulated family structure enabled the young birds to get familiar with the habitat and to learn foraging whilst enjoying permanent protection. Being guided by only two persons the birds did not become too tame; they ignored other people and learned to avoid dangerous man made situations (e.g. cars, roads, dogs). The ability of our birds to orientate, their feeding behaviour, choice of food and use of habitat were identical to what is known of Waldrapp Ibises of the same age living in the wild, for example in the colonies in Morocco. The successful pilot study is considered to be the basis for a releasing program intended in a protected area of southern Spain.相似文献
1000.