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991.
Helmut Kruckenberg Thomas M��ller Conrad Freuling Ralph-Udo M��hle Anja Globig Horst Schirrmeier Melanie Buss Timm Harder Matthias Kramer Kathrin Teske Kees Polderdijk Dieter Wallschl?ger Andreas Hlinak 《European Journal of Wildlife Research》2011,57(5):1025-1032
In order to investigate the potential role of arctic geese in the epidemiology, the spatial and temporal spread of selected avian diseases, in autumn 2002, a virological and serological survey designed as capture-mark-resighting study was conducted in one of the most important coastal resting sites for migratory waterfowl in Germany. Oropharyngeal, cloacal swabs and blood samples were collected from a total of 147 birds comprising of three different arctic geese species including White-fronted Goose (Anser albifrons), Tundra Bean Goose (Anser fabalis rossicus), Pink-footed Goose (Anser brachyrhynchus) as well as from 29 non-migratory Canada Geese (Branta canadensis). Altogether, six adeno-like viruses (ALV; 95% CI, 1.74?C9.92%) and two avian paramyxoviruses (APMV-4; 95% CI, 0.19?C5.53%) were isolated mainly from juvenile White-fronted Geese. In addition, four Canada Geese were infected with lentogenic APMV-1 (95% CI, 3.89?C31.66%) at the date of sampling. No avian influenza viruses, reo-like viruses could be isolated despite serological evidence. Likewise, no evidence of current or previous infection by West Nile virus was found. Of the 147 birds tagged in the following years, 137 birds were re-sighted between 2002 and 2008 accumulating to 1925 sightings. About 90% of all sightings were reported from the main wintering and resting sites in Germany and The Netherlands. Eight of the resighted geese were virus positive (ALV and APMV-4) at the time point of sampling in 2002. 相似文献
992.
Reno PL McCollum MA Cohn MJ Meindl RS Hamrick M Lovejoy CO 《Journal of experimental zoology. Part B. Molecular and developmental evolution》2008,310(3):240-258
Anthropoids in general and hominoids in particular exhibit differential adaptations in forearm and digital skeletal proportions to a diverse array of locomotor modes. Hox genes act as selector genes with spatially regulated expression patterns during development. Their expression in the forelimb appears to define modules that specify differential skeletal growth. Here we explore forelimb skeletal proportions in a large sample of anthropoids from a background provided by Hoxd expression patterns in late-stage murine embryonic forelimbs. Interspecific correlation and principal components analyses of primate forelimb data indicate that morphological variation in anthropoids reflects well-defined developmental modules downstream of Hoxd expression. The phalanges of digit one appear to represent a single growth module, whereas the metacarpals and manual phalanges of the posterior digits correspond to a second, independent, expression territory that extends proximally into the distal zeugopod. In particular, hominoids show very high correlations among the posterior digits and the independence of digit one. In addition, the distal radius is generally highly correlated with the posterior digits and not digit one. Relying on established functional differences among Hox paralogs, we present a model that parsimoniously explains hominoid forearm and digital proportions as a consequence of downstream effects of Hox. We, therefore, suggest that Hox-defined developmental modules have served as evolutionary modules during manual evolution in anthropoids. 相似文献
993.
Fischer C Zultanski SL Zhou H Methot JL Brown WC Mampreian DM Schell AJ Shah S Nuthall H Hughes BL Smotrov N Kenific CM Cruz JC Walker D Bouthillette M Nikov GN Savage DF Jeliazkova-Mecheva VV Diaz D Szewczak AA Bays N Middleton RE Munoz B Shearman MS 《Bioorganic & medicinal chemistry letters》2011,21(13):4083-4087
Synthesis, SAR, and evaluation of aryl triazoles as novel gamma secretase modulators (GSMs) are presented in this communication. Starting from the literature and in-house leads, we evaluated a range of five-membered heterocycles as replacements for olefins commonly found in non-acid GSMs. 1,2,3-C-aryl-triazoles were identified as suitable replacements which exhibited good modulation of γ-secretase activity, excellent pharmacokinetics and good central lowering of Aβ42 in Sprague-Dawley rats. 相似文献
994.
Laederich MB Degnin CR Lunstrum GP Holden P Horton WA 《The Journal of biological chemistry》2011,286(22):19597-19604
Fibroblast growth factor receptor 3 (FGFR3) is a key regulator of growth and differentiation, whose aberrant activation causes a number of genetic diseases including achondroplasia and cancer. Hsp90 is a specialized molecular chaperone involved in stabilizing a select set of proteins termed clients. Here, we delineate the relationship of Hsp90 and co-chaperone Cdc37 with FGFR3 and the FGFR family. FGFR3 strongly associates with these chaperone complexes and depends on them for stability and function. Inhibition of Hsp90 function using the geldanamycin analog 17-AAG induces the ubiquitination and degradation of FGFR3 and reduces the signaling capacity of FGFR3. Other FGFRs weakly interact with these chaperones and are differentially influenced by Hsp90 inhibition. The Hsp90-related ubiquitin ligase CHIP is able to interact and destabilize FGFR3. Our results establish FGFR3 as a strong Hsp90 client and suggest that modulating Hsp90 chaperone complexes may beneficially influence the stability and function of FGFR3 in disease. 相似文献
995.
Forest fragmentation and selective logging have inconsistent effects on multiple animal-mediated ecosystem processes in a tropical forest 总被引:1,自引:0,他引:1
Schleuning M Farwig N Peters MK Bergsdorf T Bleher B Brandl R Dalitz H Fischer G Freund W Gikungu MW Hagen M Garcia FH Kagezi GH Kaib M Kraemer M Lung T Naumann CM Schaab G Templin M Uster D Wägele JW Böhning-Gaese K 《PloS one》2011,6(11):e27785
Forest fragmentation and selective logging are two main drivers of global environmental change and modify biodiversity and environmental conditions in many tropical forests. The consequences of these changes for the functioning of tropical forest ecosystems have rarely been explored in a comprehensive approach. In a Kenyan rainforest, we studied six animal-mediated ecosystem processes and recorded species richness and community composition of all animal taxa involved in these processes. We used linear models and a formal meta-analysis to test whether forest fragmentation and selective logging affected ecosystem processes and biodiversity and used structural equation models to disentangle direct from biodiversity-related indirect effects of human disturbance on multiple ecosystem processes. Fragmentation increased decomposition and reduced antbird predation, while selective logging consistently increased pollination, seed dispersal and army-ant raiding. Fragmentation modified species richness or community composition of five taxa, whereas selective logging did not affect any component of biodiversity. Changes in the abundance of functionally important species were related to lower predation by antbirds and higher decomposition rates in small forest fragments. The positive effects of selective logging on bee pollination, bird seed dispersal and army-ant raiding were direct, i.e. not related to changes in biodiversity, and were probably due to behavioural changes of these highly mobile animal taxa. We conclude that animal-mediated ecosystem processes respond in distinct ways to different types of human disturbance in Kakamega Forest. Our findings suggest that forest fragmentation affects ecosystem processes indirectly by changes in biodiversity, whereas selective logging influences processes directly by modifying local environmental conditions and resource distributions. The positive to neutral effects of selective logging on ecosystem processes show that the functionality of tropical forests can be maintained in moderately disturbed forest fragments. Conservation concepts for tropical forests should thus include not only remaining pristine forests but also functionally viable forest remnants. 相似文献
996.
Sbiera S Dexneit T Reichardt SD Michel KD van den Brandt J Schmull S Kraus L Beyer M Mlynski R Wortmann S Allolio B Reichardt HM Fassnacht M 《PloS one》2011,6(9):e24345
Background
Pre- and early clinical studies on patients with autoimmune diseases suggested that induction of regulatory T(Treg) cells may contribute to the immunosuppressive effects of glucocorticoids(GCs).Objective
We readdressed the influence of GC therapy on Treg cells in immunocompetent human subjects and naïve mice.Methods
Mice were treated with increasing doses of intravenous dexamethasone followed by oral taper, and Treg cells in spleen and blood were analyzed by FACS. Sixteen patients with sudden hearing loss but without an inflammatory disease received high-dose intravenous prednisolone followed by stepwise dose reduction to low oral prednisolone. Peripheral blood Treg cells were analyzed prior and after a 14 day GC therapy based on different markers.Results
Repeated GC administration to mice for three days dose-dependently decreased the absolute numbers of Treg cells in blood (100 mg dexamethasone/kg body weight: 2.8±1.8×104 cells/ml vs. 33±11×104 in control mice) and spleen (dexamethasone: 2.8±1.9×105/spleen vs. 95±22×105/spleen in control mice), which slowly recovered after 14 days taper in spleen but not in blood. The relative frequency of FOXP3+ Treg cells amongst the CD4+ T cells also decreased in a dose dependent manner with the effect being more pronounced in blood than in spleen. The suppressive capacity of Treg cells was unaltered by GC treatment in vitro. In immunocompetent humans, GCs induced mild T cell lymphocytosis. However, it did not change the relative frequency of circulating Treg cells in a relevant manner, although there was some variation depending on the definition of the Treg cells (FOXP3+: 4.0±1.5% vs 3.4±1.5%*; AITR+: 0.6±0.4 vs 0.5±0.3%, CD127low: 4.0±1.3 vs 5.0±3.0%* and CTLA4+: 13.8±11.5 vs 15.6±12.5%; * p<0.05).Conclusion
Short-term GC therapy does not induce the hitherto supposed increase in circulating Treg cell frequency, neither in immunocompetent humans nor in mice. Thus, it is questionable that the clinical efficacy of GCs is achieved by modulating Treg cell numbers. 相似文献997.
Carola Marzi Lesca M Holdt Giovanni Fiorito Pei-Chien Tsai Anja Kretschmer Simone Wahl Simonetta Guarrera Daniel Teupser Tim D. Spector Licia Iacoviello Carlotta Sacerdote Konstantin Strauch Serene Lee Wolfgang E. Thasler Annette Peters Barbara Thorand Petra Wolf Holger Prokisch Rosario Tumino Christian Gieger Vittorio Krogh Salvatore Panico Jordana T. Bell Giuseppe Matullo Melanie Waldenberger Harald Grallert Wolfgang Koenig 《PloS one》2016,11(11)
BackgroundElevated levels of C-reactive protein (CRP, determined by a high-sensitivity assay) indicate low-grade inflammation which is implicated in many age-related disorders. Epigenetic studies on CRP might discover molecular mechanisms underlying CRP regulation. We aimed to identify DNA methylation sites related to CRP concentrations in cells and tissues regulating low-grade inflammation.ResultsGenome-wide DNA methylation was measured in peripheral blood in 1,741 participants of the KORA F4 study using Illumina HumanMethylation450 BeadChip arrays. Four CpG sites (located at BCL3, AQP3, SOCS3, and cg19821297 intergenic at chromosome 19p13.2, P ≤ 1.01E-07) were significantly hypomethylated at high CRP concentrations independent of various confounders including age, sex, BMI, smoking, and white blood cell composition. Findings were not sex-specific. CRP-related top genes were enriched in JAK/STAT pathways (Benjamini-Hochberg corrected P < 0.05). Results were followed-up in three studies using DNA from peripheral blood (EPICOR, n = 503) and adipose tissue (TwinsUK, n = 368) measured as described above and from liver tissue (LMU liver cohort, n = 286) measured by MALDI-TOF mass spectrometry using EpiTYPER. CpG sites at the AQP3 locus (significant p-values in peripheral blood = 1.72E-03 and liver tissue = 1.51E-03) and the SOCS3 locus (p-values in liver < 2.82E-05) were associated with CRP in the validation panels.ConclusionsEpigenetic modifications seem to engage in low-grade inflammation, possibly via JAK/STAT mediated pathways. Results suggest a shared relevance across different tissues at the AQP3 locus and highlight a role of DNA methylation for CRP regulation at the SOCS3 locus. 相似文献
998.
In midsummer 2002–2003, intense wildfires raged through the Brindabella Range of south‐eastern Australia, including sites where we have studied the ecology of scincid lizards (especially Bassiana duperreyi) for decades. Data‐loggers measured the thermal regimes experienced by eggs during these fires (revealing lethally high temperatures in nests under logs in the forest but minimal effect in nests under rocks in clearings). Eggs from forest‐clearing nests hatched successfully. Reproductive output of lizards in one area was reduced in the years post‐fire (perhaps because of inadequate food [insect] abundance to fuel female reproduction) but soon recovered. The fires reduced vegetation density and thus increased the availability of sun‐exposed rocks that serve as potential nest sites. However, the magnitude and duration of these effects differed among sites. Five years after these intense fires, canopy openness (and thus, sunlight penetration to create thermally suitable nest sites) was indistinguishable from pre‐fire conditions. Our data reveal strong spatial heterogeneity both in the immediate effects of fire on lizard reproduction and in longer‐term post‐fire changes in habitat quality. Surprisingly, these intense wildfires had only transitory and local effects on nest‐site availability for the heliothermic lizards that we study, but impacts likely were more severe on sympatric taxa that depend upon moist cool microhabitats. 相似文献
999.
Seok Heo Jae‐Won Yang Marie L. Huber Melanie Planyavsky Keiryn L. Bennett Gert Lubec 《Proteomics》2012,12(22):3338-3342
The 5‐hydroxytryptamine 1A receptor (serotonin 1A receptor; 5‐HT1AR) is involved in a large series of brain functions, and roles in anxiety, depression, and cognition have been reported. So far, published information on mass spectrometrical characterization of 5‐HT1AR is limited to the presence of two 5‐HT1AR peptides in rat's whole brain as observed by in‐solution digestion followed by LC‐MS/MS. Knowledge about the protein sequence and PTMs, however, would have implications for generation of specific antibodies and designing studies on the 5‐HT1AR at the protein level. A rat recombinant 5‐HT1AR was extracted from the tsA201 cell line, run using several gel‐based principles with subsequent in‐gel digestion with several proteases, chymotrypsin, trypsin, AspN, proteinase K, and pepsin followed by nano‐LC‐ESI‐MS/MS analysis on a high capacity ion trap and an LTQ Orbitrap Velos. Using two search engines, Mascot and Modiro?, the recombinant 5‐HT1AR was identified showing 94.55% sequence coverage. A single phosphorylation at S301 was identified and verified by phosphatase treatment and a series of amino acid substitutions were detected. Characterization of 5‐HT1AR, a key player of brain functions and neurotransmission, was shown and may enable generation of specific antibodies, design of future, and interpretation of previous studies in the rat at the protein level. 相似文献
1000.
Corynebacterium glutamicum, an established industrial amino acid producer, has been genetically modified for efficient succinate production from the renewable carbon source glucose under fully aerobic conditions in minimal medium. The initial deletion of the succinate dehydrogenase genes (sdhCAB) led to an accumulation of 4.7 g l?1 (40 mM) succinate as well as high amounts of acetate (125 mM) as by‐product. By deleting genes for all known acetate‐producing pathways (pta‐ackA, pqo and cat) acetate production could be strongly reduced by 83% and succinate production increased up to 7.8 g l?1 (66 mM). Whereas overexpression of the glyoxylate shunt genes (aceA and aceB) or overproduction of the anaplerotic enzyme pyruvate carboxylase (PCx) had only minor effects on succinate production, simultaneous overproduction of pyruvate carboxylase and PEP carboxylase resulted in a strain that produced 9.7 g l?1 (82 mM) succinate with a specific productivity of 1.60 mmol g (cdw)?1 h?1. This value represents the highest productivity among currently described aerobic bacterial succinate producers. Optimization of the production conditions by decoupling succinate production from cell growth using the most advanced producer strain (C. glutamicumΔpqoΔpta‐ackAΔsdhCABΔcat/pAN6‐pycP458Sppc) led to an additional increase of the product yield to 0.45 mol succinate mol?1 glucose and a titre of 10.6 g l?1 (90 mM) succinate. 相似文献