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901.
Kim DW Lee JH Park SK Yang WM Jeon GS Lee YH Chung CK Cho SS 《Neurochemical research》2007,32(9):1460-1468
Glycogen synthase kinase 3β (GSK3β) is believed to play important roles in the regulation of synaptic plasticity, cell survival
and circadian rhythms in the mature CNS. However, although several studies have been focused on the GSK3β, little is known
about GSK3β changes in glial cells under neuropathological conditions. In this study, we evaluated the expressions of molecules
associated with the GSK3β signaling pathway, following the induction of an excitotoxic lesion in mouse brain by kainic acid
(KA) injection, which caused pyramidal cell degeneration in the hippocampal CA3 region. In injured hippocampi, Ser47-Akt (protein
kinase B, PKB) phosphorylation increased from 4 h until 1 day post-injection (PI). Ser9-GSK3β and Ser133-cAMP responsive element-binding
protein (CREB) phosphorylations showed similar spatiotemporal patterns in hippocampi at 1 day until 3 days PI. Double immunohistochemistry
also showed that these phosphorylated forms of Akt, GSK3β and CREB were expressed in astrocytes. For the first time, our data
demonstrate the injury-induced astrocytic changes in the levels of phosphorylation of Akt, -GSK3β and -CREB in vivo, which
may reflect mechanisms of glial cells protection or adaptive response to damage.
DW Kim and JH Lee contributed equally to this work. 相似文献
902.
Many studies of contingency judgments have used a task in which, on each trial, the participant is free either to respond or not to respond, and an outcome may, or may not, be presented. Typically, the experimenter specifies a nominal value for the contingency between responding and outcome, but the actual values of a variety of variables experienced by a particular participant depend on that participant's frequency of responding. The results of computer simulations of various strategies for implementing the contingency manipulation, and the results of an experiment, indicate that the same nominal contingency value will lead to considerable variability in the actual contingency experienced by participants. Moreover, nominal contingency manipulations are confounded with the probability that the subject experiences an outcome. While researchers might be aware of these issues, not enough attention has been paid to their potential impact. 相似文献
903.
904.
A coupled achiral-chiral high performance liquid chromatographic method was developed and fully validated for the determination of bevantolol enantiomers, (-)-(S)-bevantolol and (+)-(R)-bevantolol, in human plasma. Plasma samples were prepared by solid phase extraction with Sep-Pak Plus C18 cartridges followed by HPLC. Bevantolol enantiomers and (+)-(R)-Propranolol as internal standard (IS) were preseparated from interfering components in plasma on a Phenomenex silica column and bevantolol enantiomers and IS were resolved and determined on a Chiralcel OJ-H chiral stationary phase. The two columns were connected by a switching valve equipped with silica precolumn. The Precolumn was used to concentrate bevantolol in the eluent from the achiral column before back flushing onto chiral phase. A detailed validation of the method was performed accordingly to FDA guidelines. For each enantiomer the assay was linear between 20 and 1600 ng/ml. The quantification limits of both bevantolol enantiomers were 20 ng/ml. The intraday variation was between 1.07 and 12.64% in relation to the measured concentration and the interday variation was 0.91 and 11.79%. The method has been applied to the determination of (-)-(S)- and (+)-(R)-bevantolol in plasma from healthy volunteers dosed with racemic bevantolol hydrochloride. 相似文献
905.
Antiadhesive property of microalgal polysaccharide extract on the binding of Helicobacter pylori to gastric mucin 总被引:1,自引:0,他引:1
The emergence of antibiotic-resistant Helicobacter pylori is of concern in the treatment of H. pylori-associated gastroduodenal diseases. As the organism was reported to bind gastric mucin, we used porcine gastric mucin as substrate to assess the antiadhesive property of polysaccharides derived from Spirulina (PS), a commercially available microalga, against the binding of H. pylori to gastric mucin. Results show that polysaccharides prevented H. pylori from binding to gastric mucin optimally at pH 2.0, without affecting the viability of either bacteria or gastric epithelial cells, thus favouring its antiadhesive action in a gastric environment. Using ligand overlay analysis, polysaccharide was demonstrated to bind H. pylori alkyl hydroperoxide reductase (AhpC) and urease, which have shown here to possess mucin-binding activity. An in vivo study demonstrated that bacteria load was reduced by >90% in BALB/c mice treated with either Spirulina or polysaccharides. It is thus suggested that polysaccharides may function as a potential antiadhesive agent against H. pylori colonization of gastric mucin. 相似文献
906.
907.
Background
Gene clustering has been widely used to group genes with similar expression pattern in microarray data analysis. Subsequent enrichment analysis using predefined gene sets can provide clues on which functional themes or regulatory sequence motifs are associated with individual gene clusters. In spite of the potential utility, gene clustering and enrichment analysis have been used in separate platforms, thus, the development of integrative algorithm linking both methods is highly challenging. 相似文献908.
Sang Hyun Lee Thanh Thi Ngoc Doan Sung Ho Ha Woo-Jin Chang Yoon-Mo Koo 《Journal of Molecular Catalysis .B, Enzymatic》2007,47(3-4):129-134
The immobilization of lipase from Candida rugosa, using ionic liquids as additives to protect the inactivation of lipase by released alcohol and shrinking of gel during sol–gel process, was investigated. The influence of various factors, such as structure of ionic liquids, content of ionic liquids and types of precursor in the sol–gel process on the activity and stability of immobilized lipase was also studied. The highest hydrolytic activity of immobilized lipase was obtained when the hydrophilic ionic liquid, [C2mim][BF4], was used as an additive, while the highest stability of immobilized lipase was obtained by using hydrophobic ionic liquid, [C16mim][Tf2N]. Therefore, the binary mixtures of these ionic liquids as additives were used to obtain the optimal immobilized lipase, which shows both high activity and stability. The hydrolysis and esterification activities of lipase co-immobilized with the mixture of 1:1 at molar ratio of [C2mim][BF4] and [C16mim][Tf2N] were 10-fold and 14-fold greater than in silica gel without ionic liquids (ILs), respectively. After 5 days incubation of this immobilized lipase in n-hexane at 50 °C, 84% of initial activity was remained, while the residual activity of the lipase immobilized without ILs was 28%. 相似文献
909.
Background
Brucella species include economically important zoonotic pathogens that can infect a wide range of animals. There are currently six classically recognised species of Brucella although, as yet unnamed, isolates from various marine mammal species have been reported. In order to investigate genetic relationships within the group and identify potential diagnostic markers we have sequenced multiple genetic loci from a large sample of Brucella isolates representing the known diversity of the genus. 相似文献910.
The promotion of polycyclic aromatic hydrocarbon (PAH) degradation was demonstrated in the rhizosphere of Festuca arundinacea with Pseudomonas fluorescens. P. fluorescens 5RL more significantly interacted with salicylate and dextrose in the agar containing tall fescue than agar without plant roots. Although the presence of tall fescue did not promote catabolic enzyme induction in the absence of salicylate, an increase in dioxygenase activity relative to no plant controls implies that this plant may enhance the degradation of PAHs or facilitate the genotypes that are capable of transforming PAH in the rhizosphere. 相似文献