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991.
992.
Christian T. Hellwig M. Eugenia Delgado Josip Skoko Lydia Dyck Carol Hanna Alexa Wentges Claudia Langlais Cathrin Hagenlocher Alexandra Mack David Dinsdale Kelvin Cain Marion MacFarlane Markus Rehm 《Cell death and differentiation》2022,29(1):147
Cancer cells that are resistant to Bax/Bak-dependent intrinsic apoptosis can be eliminated by proteasome inhibition. Here, we show that proteasome inhibition induces the formation of high molecular weight platforms in the cytosol that serve to activate caspase-8. The activation complexes contain Fas-associated death domain (FADD) and receptor-interacting serine/threonine-protein kinase 1 (RIPK1). Furthermore, the complexes contain TRAIL-receptor 2 (TRAIL-R2) but not TRAIL-receptor 1 (TRAIL-R1). While RIPK1 inhibition or depletion did not affect proteasome inhibitor-induced cell death, TRAIL-R2 was found essential for efficient caspase-8 activation, since the loss of TRAIL-R2 expression abrogated caspase processing, significantly reduced cell death, and promoted cell re-growth after drug washout. Overall, our study provides novel insight into the mechanisms by which proteasome inhibition eliminates otherwise apoptosis-resistant cells, and highlights the crucial role of a ligand-independent but TRAIL-R2-dependent activation mechanism for caspase-8 in this scenario.Subject terms: Cell biology, Molecular biology, Experimental models of disease 相似文献
993.
Leticia Labriola Maria G Peters Karin Krogh Iván Stigliano Letícia F Terra Cecilia Buchanan Marcel CC Machado Elisa Bal de Kier Joffé Lydia Puricelli Mari C Sogayar 《BMC cell biology》2009,10(1):49-16
Background
The in vitro culture of insulinomas provides an attractive tool to study cell proliferation and insulin synthesis and secretion. However, only a few human beta cell lines have been described, with long-term passage resulting in loss of insulin secretion. Therefore, we set out to establish and characterize human insulin-releasing cell lines. 相似文献994.
Camouflage is a means to defeat visual detection by predators, whereas visual communication involves a signal that is conspicuous to a receiver (usually a conspecific). However, most intraspecific visual signals are also conspicuous to predators, so that signalling can lead to the serious consequence of predation. Could an animal achieve visual camouflage and simultaneously send a hidden visual message to a conspecific? Here, we present evidence that the polarized aspect of iridescent colour in squid skin is maintained after it passes through the overlying pigmented chromatophores, which produce the highly evolved--and dynamically changeable--camouflaged patterns in cephalopods. Since cephalopods are polarization sensitive, and can regulate polarization via skin iridescence, it is conceivable that they could send polarized signals to conspecifics while staying camouflaged to fish or mammalian predators, most of which are not polarization sensitive. 相似文献
995.
Robert W. Georgantas III Katie Streicher Xiaobing Luo Lydia Greenlees Wei Zhu Zheng Liu Philip Brohawn Christopher Morehouse Brandon W. Higgs Laura Richman Bahija Jallal Yihong Yao Koustubh Ranade 《Pigment cell & melanoma research》2014,27(2):275-286
Expression profiling of microRNAs in melanoma lesional skin biopsies compared with normal donor skin biopsies, as well as melanoma cell lines compared with normal melanocytes, revealed that hsa‐miR‐206 was down‐regulated in melanoma (?75.4‐fold, P = 1.7 × 10?4). MiR‐206 has been implicated in a large number of cancers, including breast, lung, colorectal, ovarian, and prostate cancers; however, its role in tumor development remains largely unknown, its biologic function is poorly characterized, and its targets affecting cancer cells are largely unknown. MiR‐206 reduced growth and migration/invasion of multiple melanoma cell lines. Bioinformatics identified cell cycle genes CDK2, CDK4, Cyclin C, and Cyclin D1 as strong candidate targets. Western blots and 3′UTR reporter gene assays revealed that miR‐206 inhibited translation of CDK4, Cyclin D1, and Cyclin C. Additionally, hsa‐miR‐206 transfection induced G1 arrest in multiple melanoma cell lines. These observations support hsa‐miR‐206 as a tumor suppressor in melanoma and identify Cyclin C, Cyclin D1, and CDK4 as miR‐206 targets. 相似文献
996.
To realize the therapeutic potential of RNA drugs, efficient, tissue-specific and nonimmunogenic delivery technologies must be developed. Here we show that exosomes-endogenous nano-vesicles that transport RNAs and proteins-can deliver short interfering (si)RNA to the brain in mice. To reduce immunogenicity, we used self-derived dendritic cells for exosome production. Targeting was achieved by engineering the dendritic cells to express Lamp2b, an exosomal membrane protein, fused to the neuron-specific RVG peptide. Purified exosomes were loaded with exogenous siRNA by electroporation. Intravenously injected RVG-targeted exosomes delivered GAPDH siRNA specifically to neurons, microglia, oligodendrocytes in the brain, resulting in a specific gene knockdown. Pre-exposure to RVG exosomes did not attenuate knockdown, and non-specific uptake in other tissues was not observed. The therapeutic potential of exosome-mediated siRNA delivery was demonstrated by the strong mRNA (60%) and protein (62%) knockdown of BACE1, a therapeutic target in Alzheimer's disease, in wild-type mice. 相似文献
997.
Renner L von Soosten D Sipka A Döll S Beineke A Schuberth HJ Dänicke S 《Archives of animal nutrition》2012,66(2):73-85
Twenty-five primiparous Holstein cows were divided into five experimental groups (five animals per group) by different feeding (control fat preparation [CON] or conjugated linoleic acid [CLA] supplement) and slaughtering times. The daily consumption of CLA was 6.0 g of the trans-10, cis-12 CLA-isomer and 5.7 g cis-9, trans-11 CLA isomer. An initial group (IG) was slaughtered one day post partum (pp) and the remaining 20 animals after 42 and 105 days pp, respectively. Blood for peripheral blood mononuclear cells (PBMC) separation was taken seven days ante partum and immediately before slaughter. The spleen was removed during dissection for isolation of splenocytes and samples for histopathological examination. Cell viability and Concanavalin A-stimulated proliferation was analysed by MTT and Alamar Blue assay. Basal expression of cytokines (interleukin [IL]-4, IL-10, IL-12, tumour necrosis factor alpha [TNF-alpha] and interferon gamma [IFN-gamma]) was measured by quantitative real time polymerase chain reaction (qRT-PCR) in unstimulated PMBC and splenocytes. With PBMC, stimulation indices increased from 1 day pp to 105 days pp with no differences between CLA and CON groups. With splenocytes, the stimulation index of the CLA group was lower compared to CON group 105 days pp. Baseline expression of cytokines was not effected by CLA feeding comparing similar time points. Also, no differences occurred in the expression of IL-4 in PBMC and IL-10 as well as TNF-alpha in both cell populations, when comparing the feeding groups separately with IG. IL-4 was more frequently expressed in CLA group 42 days pp in splenocytes. IFN-gamma expression was increased 105 days pp in CLA group in splenocytes and PBMC. IL-12 was higher expressed 105 days (PBMC) or 42 days pp (splenocytes) when compared to IG. There was no effect of CLA feeding or slaughter time on histopathology of the spleen. In conclusion, the present results demonstrate an inhibiting effect of CLA on the mitogen-induced activation of splenocytes. 相似文献
998.
Else Eising Sjoerd M. H. Huisman Ahmed Mahfouz Lisanne S. Vijfhuizen Verneri Anttila Bendik S. Winsvold Tobias Kurth M. Arfan Ikram Tobias Freilinger Jaakko Kaprio Dorret I. Boomsma Cornelia M. van Duijn Marjo-Riitta R. Järvelin John-Anker Zwart Lydia Quaye David P. Strachan Christian Kubisch Martin Dichgans George Davey Smith Kari Stefansson Aarno Palotie Daniel I. Chasman Michel D. Ferrari Gisela M. Terwindt Boukje de Vries Dale R. Nyholt Boudewijn P. F. Lelieveldt Arn M. J. M. van den Maagdenberg Marcel J. T. Reinders 《Human genetics》2016,135(4):425-439
999.
Lydia V. Luncz Magdalena S. Svensson Michael Haslam Suchinda Malaivijitnond Tomos Proffitt Michael Gumert 《International journal of primatology》2017,38(5):872-880
Anthropogenic disturbances have a detrimental impact on the natural world; the vast expansion of palm oil monocultures is one of the most significant agricultural influences. Primates worldwide consequently have been affected by the loss of their natural ecosystems. Long-tailed macaques (Macaca fascilularis) in Southern Thailand have, however, learned to exploit oil palm nuts using stone tools. Using camera traps, we captured the stone tool behavior of one macaque group in Ao Phang-Nga National Park. Line transects placed throughout an abandoned oil palm plantation confirmed a high abundance of nut cracking sites. Long-tailed macaques previously have been observed using stone tools to harvest shellfish along the coasts of Thailand and Myanmar. The novel nut processing behavior indicates the successful transfer of existing lithic technology to a new food source. Such behavioral plasticity has been suggested to underlie cultural behavior in animals, suggesting that long-tailed macaques have potential to exhibit cultural tendencies. The use of tools to process oil palm nuts across multiple primate species allows direct comparisons between stone tool using nonhuman primates living in anthropogenic environments. 相似文献
1000.
Erik Bannert Tanja Tesch Jeannette Kluess Hana Valenta Jana Frahm Susanne Kersten Stefan Kahlert Lydia Renner Hermann-Josef Rothkötter Sven Dänicke 《Mycotoxin Research》2017,33(3):183-195
This study aimed to investigate a potential modulatory effect of E. coli lipopolysaccharide (LPS) on the kinetics of deoxynivalenol (DON) and zearalenone (ZEN) after pre- or post-hepatic LPS administration to unravel the putative role of the liver. Fifteen barrows were fed a diet containing mycotoxin-contaminated maize (4.59 mg DON/kg feed, 0.22 mg ZEN/kg feed) for 29 days and equipped with pre-hepatic catheters (portal vein, “po”) and post-hepatic catheters (jugular vein, “ju”), facilitating simultaneous infusion of LPS (“LPS group”, 7.5 μg/kg body weight) or 0.9% sterile NaCl solution (control, “CON group”, equivolumar to LPS group) and blood sampling. This resulted in three infusion groups, depending on infusion site: CONju-CONpo, CONju-LPSpo, and LPSju-CONpo. On day 29, pigs were fed their morning ration (700 g/pig) (?15 min), and blood samples were collected at regular intervals relative to infusion start. At 195 min, pigs were sacrificed and bile, urine, liquor, and liver samples collected. DON concentrations in jugular and portal blood decreased in both LPS-infused groups, whereas the ZEN concentrations increased, regardless of the treatment site. In liver tissue, a decrease of both toxin concentrations was observed in endotoxaemic pigs as well as a drop in hepatic conjugation, regardless of LPS entry site. In contrast to our hypothesis, DON and ZEN were not differently altered depending on the LPS-entry site. Neither the absorption nor the accumulation of DON and ZEN in different tissues differed significantly between animals which were infused with LPS via either the jugular or portal vein. 相似文献