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991.
Stress and negative moods, which are thought to be partly mediated by reduced brain serotonin function, often increase emotional eating in dieting women (restrainers). Because the short (S) allele polymorphism in the serotonin transporter gene (5-HTTLPR) is associated with serotonin dysfunction, S allele compared to long (L) allele 5-HTTLPR genotypes may be more susceptible to stress-induced emotional eating. Consequently, serotonin challenge via tryptophan (TRP)-rich protein hydrolysate (TPH) may alleviate stress-induced emotional eating particularly in S/S allele carriers. We tested whether acute stress affects emotional eating in women with high or low dietary restraints depending on their 5-HTTLPR genotype and TPH intake. Nineteen female subjects who were homozygous for the short-allele 5-HTTLPR genotype (S'/S'=S/L(G), L(G)/L(G): restrainers vs. nonrestrainers) and 23 female subjects who were homozygous for the long-allele 5-HTTLPR genotype (L'/L'=L(A)/L(A): restrainers vs. nonrestrainers) were tested in a double-blind, placebo-controlled crossover study of stress-induced emotional eating following intake of TPH or a placebo. TPH intake significantly increased the plasma TRP/large neutral amino acid ratio (P<.0001) in the L'/L' group (70%) compared to the S'/S' group (30%). TPH reduced food intake in both groups, but in the L'/L' group, it also reduced stress-induced negative mood (P=.037) and the desire for sweet, high-fat foods (P=.011) regardless of dietary restraint. Conclusions: Since TPH caused a greater increase in the plasma TRP/large neutral amino acid ratio in the L'/L' group compared to S'/S' group, the exclusive beneficial effects of L'/L' genotype may be due to enhanced brain 5-HT function.  相似文献   
992.
We describe the design, synthesis, and evaluation of benzimidazoles as benzamide replacements within a series of trisubstituted cyclohexane CCR2 antagonists. 7-Trifluoromethylbenzimidazoles displayed potent binding and functional antagonism of CCR2 while being selective over CCR3. These benzimidazoles were also incorporated into lactam-containing antagonists, thus completely eliminating the customary bis-amide.  相似文献   
993.
Here we describe the synthesis and characterization of a number of 3-amino-1H-indazol-6-yl-benzamides that were designed to target the 'DFG-out' conformation of the kinase activation loop. Several compounds such as 4 and 11 exhibit single-digit nanomolar EC(50)s against FLT3, c-Kit and the gatekeeper T674M mutant of PDGFRα.  相似文献   
994.
Understanding how polygenic traits evolve under selection is an unsolved problem, because challenges exist for identifying genes underlying a complex trait and understanding how multilocus selection operates in the genome. Here we study polygenic response to selection using artificial selection experiments. Inbred strains from seven independent long-term selection experiments for extreme mouse body weight ("high" lines weigh 42-77 g versus 16-40 g in "control" lines) were genotyped at 527,572 SNPs to identify loci controlling body weight. We identified 67 parallel selected regions (PSRs) where high lines share variants rarely found among the controls. By comparing allele frequencies in one selection experiment against its unselected control, we found classical selective sweeps centered on the PSRs. We present evidence supporting two G protein-coupled receptors GPR133 and Prlhr as positional candidates controlling body weight. Artificial selection may mimic natural selection in the wild: compared to control loci, we detected reduced heterozygosity in PSRs in unusually large wild mice on islands. Many PSRs overlap loci associated with human height variation, possibly through evolutionary conserved functional pathways. Our data suggest that parallel selection on complex traits may evoke parallel responses at many genes involved in diverse but relevant pathways.  相似文献   
995.
Leaf lesions of Mandevilla sanderi were shown to be caused by Pseudomonas savastanoi. While BOX fingerprints were similar for P. savastanoi isolates from different host plants, plasmid restriction patterns and sequencing of plasmid-located pathogenicity determinants revealed that Mandevilla isolates contained similar plasmids distinct from those of other isolates. A repA-based detection method was established.  相似文献   
996.
The problem of plant individuality is something which has vexed botanists throughout the ages, with fashion swinging back and forth from treating plants as communities of individuals (Darwin 1800; Braun and Stone 1853; Münch 1938) to treating them as organisms in their own right, and although the latter view has dominated mainstream thought most recently (Harper 1977; Cook 1985; Ariew and Lewontin 2004), a lively debate conducted mostly in Scandinavian journals proves that the issues are far from being resolved (Tuomi and Vuorisalo 1989b; Fagerström 1992; Pan and Price 2001). In this paper I settle the matter once and for all, by showing which elements of each side are correct.  相似文献   
997.
998.
α-Melanocyte-stimulating hormone (α-MSH)-induced activation of the melanocortin-4 receptor in hypothalamic neurons increases energy expenditure and inhibits food intake. Active hypothalamic AMP-activated protein kinase (AMPK) has recently been reported to enhance food intake, and in vivo experiments suggested that intrahypothalamic injection of melanocortins decreased food intake due to the inhibition of AMPK activity. However, it is not clear whether α-MSH affects AMPK via direct intracellular signaling cascades or if the release of paracrine factors is involved. Here, we used a murine, hypothalamic cell line (GT1-7 cells) and monitored AMPK phosphorylation at Thr(172), which has been suggested to increase AMPK activity. We found that α-MSH dephosphorylated AMPK at Thr(172) and consequently decreased phosphorylation of the established AMPK substrate acetyl-coenzyme A-carboxylase at Ser(79). Inhibitory effects of α-MSH on AMPK were blocked by specific inhibitors of protein kinase A (PKA) or ERK-1/2, pointing to an important role of both kinases in this process. Because α-MSH-induced activation of ERK-1/2 was blunted by PKA inhibitors, we propose that ERK-1/2 serves as a link between PKA and AMPK in GT1-7 cells. Furthermore, down-regulation of liver kinase B-1, but not inhibition of calcium-calmodulin-dependent kinase kinase-β or TGFβ-activated kinase-1 decreased basal phosphorylation of AMPK and its dephosphorylation induced by α-MSH. Thus, we propose that α-MSH inhibits AMPK activity via a linear pathway, including PKA, ERK-1/2, and liver kinase B-1 in GT1-7 cells. Given the importance of the melanocortin system in the formation of adipositas, detailed knowledge about this pathway might help to develop drugs targeting obesity.  相似文献   
999.
Alcohol use disorders (AUDs), including alcohol abuse and dependence, have been linked to the development of acute lung injury (ALI). Prior clinical investigations suggested an association between AUDs and abnormal alveolar epithelial permeability mediated through pulmonary oxidative stress that may partially explain this relationship. We sought to determine if correcting pulmonary oxidative stress in the setting of AUDs would normalize alveolar epithelial permeability in a double-blinded, randomized, placebo-controlled trial of Protandim, a nutraceutical reported to enhance antioxidant activity. We randomized 30 otherwise healthy AUD subjects to receive directly observed inpatient oral therapy with either Protandim (1,350 mg/day) or placebo. Subjects underwent bronchoalveolar lavage (BAL) and blood sampling before study drug administration and after 7 days of therapy; all AUD subjects completed the study protocol without adverse events. BAL total protein was measured at each timepoint as an indicator of alveolar epithelial permeability. In subjects with AUDs, before study drug initiation, BAL total protein values were not significantly higher than in 11 concurrently enrolled controls (P = 0.07). Over the 7-day study period, AUD subjects did not exhibit a significant change in BAL total protein, regardless of their randomization to Protandim {n = 14, -2% [intraquartile range (IQR), -56-146%]} or to placebo [n = 16, 77% (IQR -20-290%); P = 0.19]. Additionally, among those with AUDs, no significant changes in BAL oxidative stress indexes, epithelial growth factor, fibroblast growth factor, interleukin-1β, or interleukin-10 were observed regardless of drug type received. Plasma thiobarbituric acid reactive substances, a marker of lipid peroxidation, decreased significantly over time among AUD subjects randomized to placebo (P < 0.01). These results suggest that Protandim for 7 days in individuals with AUDs who are newly abstinent does not alter alveolar epithelial permeability. However, our work demonstrates the feasibility of safely conducting clinical trials that include serial bronchoscopies in a vulnerable population at risk for acute lung injury.  相似文献   
1000.
The transition from rolling to firm adhesion is a key element of neutrophil activation and essential to the inflammatory response. Although the molecular mediators of rolling and firm adhesion are known to be selectins and beta2 -integrins, respectively, the precise dynamic mechanism by which these ligands facilitate neutrophil arrest remains unknown. Recently, it has been shown that ligation of E-selectin can stimulate the firm adhesion of neutrophils via a MAP-kinase cascade. To study the possible mechanism by which neutrophil arrest could occur, we created an integrated model by combining two methodologies from computational biology: a mechanics-based modeling of leukocyte adhesion (adhesive dynamics) and signal transduction pathway modeling. Within adhesive dynamics, a computational method our group has shown to accurately recreate rolling dynamics, we include a generic, tunable integrin activation module that links selectin engagement to integrin and activity. This model allows us to relate properties of the activation function to the dynamics of rolling and the time and distance rolled before arrest. This integrated model allows us to understand how intracellular signaling activity can set the timescale of neutrophil activation, adhesion, and diapedesis.  相似文献   
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