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141.
142.
Mustapha Ouali Jean-Marie Ruysschaert Caroline Lonez Michel Vandenbranden 《Molecular membrane biology》2013,30(3):225-232
Cationic lipids are efficient tools to introduce nucleic acids and proteins into cells. Elucidation of the mechanism and cellular pathways associated with such transport has been relatively tedious, even though significant progress has been made in the characterization of the intracellular trafficking of lipid/DNA complexes. Surprisingly little is known about the effects of these delivery vectors on cell functioning. In this report, we show that both cationic lipids and cationic lipid/DNA complexes mobilize the intracellular calcium. Removal of extracellular calcium did not significantly abolish this effect and preincubating cells with thapsigargin led to a decrease in [Ca2+]i, indicating that calcium was released mainly from internal calcium stores sensitive to thapsigargin. Pretreatment of the cells with the phospholipase C inhibitor U73122, blocked the [Ca2+]i rise, suggesting an inositol dependent mechanism. 相似文献
143.
Salvatore Campanella Philippe Peigneux Géraldine Petit Frédéric Lallemand Mélanie Saeremans Xavier No?l Thierry Metens Mustapha Nouali Xavier De Tiège Philippe De Witte Roberta Ward Paul Verbanck 《PloS one》2013,8(4)
Background
Cerebral dysfunction is a common feature of both chronic alcohol abusers and binge drinkers. Here, we aimed to study whether, at equated behavioral performance levels, binge drinkers exhibited increased neural activity while performing simple cognitive tasks.Methods
Thirty-two participants (16 binge drinkers and 16 matched controls) were scanned using functional magnetic resonance imaging (fMRI) while performing an n-back working memory task. In the control zero-back (N0) condition, subjects were required to press a button with the right hand when the number “2″ was displayed. In the two-back (N2) condition, subjects had to press a button when the displayed number was identical to the number shown two trials before.Results
fMRI analyses revealed higher bilateral activity in the pre-supplementary motor area in binge drinkers than matched controls, even though behavioral performances were similar. Moreover, binge drinkers showed specific positive correlations between the number of alcohol doses consumed per occasion and higher activity in the dorsomedial prefrontal cortex, as well as between the number of drinking occasions per week and higher activity in cerebellum, thalamus and insula while performing the N2 memory task.Conclusions
Binge alcohol consumption leads to possible compensatory cerebral changes in binge drinkers that facilitate normal behavioral performance. These changes in cerebral responses may be considered as vulnerability factors for developing adult substance use disorders. 相似文献144.
This study has shown that the treatment of activated sludge by gamma irradiation resulted in a deterioration in the filterability, a decrease in the size of the floc particles and an increase in the organic matter present in the sludge supernatant. A significant difference was found between the results obtained for filamentous and non-filamentous sludges in relation to the amount of soluble polysaccharide produced. 相似文献
145.
Samir Ben Romdhane Fatma Tajini Mustapha Trabelsi Mohamed Elarbi Aouani Ridha Mhamdi 《World journal of microbiology & biotechnology》2007,23(9):1195-1201
Chickpea is the most cultivated grain legume in the world and it shares the first rank with faba bean in Tunisia. However,
the yield remains low, mainly due to the limited availability of N and P, and to the severe bioclimatic conditions. No inoculation
trials had been conducted on chickpea in the Tunisian soils. This paper reports the yield response to inoculation by two different
strains of Mesorhizobium ciceri, an exogenous type strain (UPMCa7T) and a selected local strain (CMG6). Field experiments were conducted in different sites in the north of Tunisia using three
chickpea cultivars (cvs. Amdoun I, Chetoui and Kasseb). Rhizobia occupying field nodules were isolated and identified using
16S rDNA typing for both inoculated and non-inoculated plots. In contrast to the exogenous strain, the local strain gave a
significant increase in nodule number and shoot dry yield in all the experimental fields for the three cultivars used. Monitoring
of the nodule occupancy showed that the local strain competed well the native populations of rhizobia. The usefulness and
the persistence of this strain in the different soils where it was introduced will be assessed further during the next years. 相似文献
146.
Habib M Noval Rivas M Chamekh M Wieckowski S Sun W Bianco A Trouche N Chaloin O Dumortier H Goldman M Guichard G Fournel S Vray B 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(11):6700-6704
Host resistance to Trypanosoma cruzi infection depends on a type 1 response characterized by a strong production of IL-12 and IFN-gamma. Amplifying this response through CD40 triggering results in control of parasitemia. Two newly synthesized molecules (<3 kDa) mimicking trimeric CD40L (mini CD40Ls(-1) and (-2)) bind to CD40, activate murine dendritic cells, and elicit IL-12 production. Wild-type but not CD40 knockout mice exhibited a sharp decrease of parasitemia and mortality when inoculated with T. cruzi mixed with miniCD40Ls. Moreover, the immunosuppression induced by T. cruzi infection was impaired in mice treated with miniCD40Ls, as shown by proliferation of splenic lymphocytes, percentage of CD8(+) T cells, and IFN-gamma production. Mice surviving T. cruzi infection in the presence of miniCD40L(-1) were immunized against a challenge infection. Our results indicate that CD40L mimetics are effective in vivo and promote the control of T. cruzi infection by overcoming the immunosuppression usually induced by the parasites. 相似文献
147.
Agonist selective modulation of tyrosine hydroxylase expression by cannabinoid ligands in a murine neuroblastoma cell line 总被引:1,自引:0,他引:1
Functional interactions between catecholamines and cannabinoid transmission systems could explain the influence of Delta(9)-tetrahydrocannabinol on several central activities. Hence, the presence of cannabinoid CB(1) receptors in tyrosine hydroxylase (TH) containing cells has been suggested, providing clue for a direct control of catecholamines synthesis. In the present study, we evidenced the constitutive expression of functional cannabinoid CB(1) receptors in N1E-115 neuroblastoma and reported on the use of this model to examine the influence of diverse cannabinoid ligands on TH expression. Exposure of the cells to the high-affinity agonist HU 210 (5 h) resulted in a significant decrease in TH content (pEC(50): 6.40). In contrast, no change was observed after a similar treatment with the structurally unrelated agonist CP 55,940. Besides, the use of a luciferase reporter assay revealed that these two agonists showed opposite influences on TH gene promoter activity. Thus, in cells expressing pTH-luc constructs, inhibition and induction of luciferase activity were respectively observed with HU 210 (pEC(50): 8.95) and CP 55,940 (pEC(50): 9.09). Pharmacological characterisation revealed that these reciprocal responses were both related to the specific activation of cannabinoid CB(1) receptor, suggesting an agonist-dependent modulation of distinct signalling pathways. While these data points out the possible pharmacological manipulation of TH expression by cannabinoid ligands, such approach should take into account the existence of agonist selective trafficking of cannabinoid CB(1) receptor signalling. 相似文献
148.
The nuclear factor kappaB-activator gene PLEKHG5 is mutated in a form of autosomal recessive lower motor neuron disease with childhood onset 下载免费PDF全文
Maystadt I Rezsöhazy R Barkats M Duque S Vannuffel P Remacle S Lambert B Najimi M Sokal E Munnich A Viollet L Verellen-Dumoulin C 《American journal of human genetics》2007,81(1):67-76
Lower motor neuron diseases (LMNDs) include a large spectrum of clinically and genetically heterogeneous disorders. Studying a large inbred African family, we recently described a novel autosomal recessive LMND variant characterized by childhood onset, generalized muscle involvement, and severe outcome, and we mapped the disease gene to a 3.9-cM interval on chromosome 1p36. We identified a homozygous missense mutation (c.1940 T-->C [p.647 Phe-->Ser]) of the Pleckstrin homology domain-containing, family G member 5 gene, PLEKHG5. In transiently transfected HEK293 and MCF10A cell lines, we found that wild-type PLEKHG5 activated the nuclear factor kappa B (NF kappa B) signaling pathway and that both the stability and the intracellular location of mutant PLEKHG5 protein were altered, severely impairing the NF kappa B transduction pathway. Moreover, aggregates were observed in transiently transfected NSC34 murine motor neurons overexpressing the mutant PLEKHG5 protein. Both loss of PLEKHG5 function and aggregate formation may contribute to neurotoxicity in this novel form of LMND. 相似文献
149.
150.
Guirat-Dhouib N Baccar Y Mustapha IB Ouederni M Chouaibi S El Fekih N Barbouche MR Fezaa B Kouki R Hmida S Mellouli F Bejaoui M 《Clinical and molecular allergy : CMA》2012,10(1):6-4