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Gender affects performance on a variety of cognitive tasks, and this impact may stem from socio-cultural factors such as gender stereotyping. Here we systematically manipulated gender stereotype messages on a social cognition task on which no initial gender gap has been documented. The outcome reveals: (i) Stereotyping affects both females and males, with a more pronounced impact on females. Yet an explicit negative message for males elicits a striking paradoxical deterioration in performance of females. (ii) Irrespective of gender and directness of message, valence of stereotype message affects performance: negative messages have stronger influence than positive ones. (iii) Directness of stereotype message differentially impacts performance of females and males: females tend to be stronger affected by implicit than explicit negative messages, whereas in males this relationship is opposite. The data are discussed in the light of neural networks underlying gender stereotyping. The findings provide novel insights into the sources of gender related fluctuations in cognition and behavior.  相似文献   
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Arms race co-evolution drives rapid adaptive changes in pathogens and in the immune systems of their hosts. Plant intracellular NLR immune receptors detect effectors delivered by pathogens to promote susceptibility, activating an immune response that halts colonization. As a consequence, pathogen effectors evolve to escape immune recognition and are highly variable. In turn, NLR receptors are one of the most diverse protein families in plants, and this variability underpins differential recognition of effector variants. The molecular mechanisms underlying natural variation in effector recognition by NLRs are starting to be elucidated. The rice NLR pair Pik-1/Pik-2 recognizes AVR-Pik effectors from the blast fungus Magnaporthe oryzae, triggering immune responses that limit rice blast infection. Allelic variation in a heavy metal associated (HMA) domain integrated in the receptor Pik-1 confers differential binding to AVR-Pik variants, determining resistance specificity. Previous mechanistic studies uncovered how a Pik allele, Pikm, has extended recognition to effector variants through a specialized HMA/AVR-Pik binding interface. Here, we reveal the mechanistic basis of extended recognition specificity conferred by another Pik allele, Pikh. A single residue in Pikh-HMA increases binding to AVR-Pik variants, leading to an extended effector response in planta. The crystal structure of Pikh-HMA in complex with an AVR-Pik variant confirmed that Pikh and Pikm use a similar molecular mechanism to extend their pathogen recognition profile. This study shows how different NLR receptor alleles functionally converge to extend recognition specificity to pathogen effectors.  相似文献   
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Two experiments examined the nature of visuo-spatial mental imagery generation and maintenance in 4-, 6-, 8-, 10-year old children and adults (N = 211). The key questions were how image generation and maintenance develop (Experiment 1) and how accurately children and adults coordinate mental and visually perceived images (Experiment 2). Experiment 1 indicated that basic image generation and maintenance abilities are present at 4 years of age but the precision with which images are generated and maintained improves particularly between 4 and 8 years. In addition to increased precision, Experiment 2 demonstrated that generated and maintained mental images become increasingly similar to visually perceived objects. Altogether, findings suggest that for simple tasks demanding image generation and maintenance, children attain adult-like precision younger than previously reported. This research also sheds new light on the ability to coordinate mental images with visual images in children and adults.  相似文献   
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In continuation of our efforts to develop new compounds with antimicrobial properties we describe design, synthesis, molecular docking study and evaluation of antimicrobial activity of seventeen novel 2-{[5-(adamantan-1-yl)-1,3,4-thiadiazol-2-yl]-imino}-5-arylidene-1,3-thiazolidin-4-ones. All compounds showed antibacterial activity against eight Gram positive and Gram negative bacterial species. Twelve out of seventeen compounds were more potent than streptomycin and all compounds exhibited higher potency than ampicillin. Compounds were also tested against three resistant bacterial strains: MRSA, P. aeruginosa and E. coli. The best antibacterial potential against ATCC and resistant strains was observed for compound 8 (2-{[5-(adamantan-1-yl)-1,3,4-thiadiazol-2-yl]-imino}-5-(4-nitrobenzylidene)-1,3thiazolidin-4-one). The most sensitive bacterium appeared to be S. typhimirium, followed by B. cereus while L. monocitogenes and M. flavus were the most resistant. Compounds were also tested for their antifungal activity against eight fungal species. All compounds exhibited antifungal activity better than the reference drugs bifonazole and ketokonazole (3-115 times). It was found that compound 8 appeared again to be the most potent. Molecular docking studies on E. coli MurB, MurA as well as C. albicans CYP 51 and dihydrofolate reductase were used for the prediction of mechanism of antibacterial and antifungal activities confirming the experimental results.  相似文献   
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Toxoplasmosis, a most common zoonosis, is caused by the protozoan parasite Toxoplasma gondii. However, there is little epidemiological information on T. gondii infections in humans and livestock animals in Russia. Therefore, in this study, the seroprevalence of T. gondii in goats in Russia was investigated. A total of 216 goats from 32 farms were investigated and 95 of them were seropositive for T. gondii. The difference in seroprevalence between the examined regions was not statistically significant. We next collected serum samples from 99 cats and 181 humans in Kazan city, the state capital of the Republic of Tatarstan, Russia, and examined their T. gondii seroprevalences. Thirty-nine of the 99 cat samples and 56 of the 181 human samples showed seropositivity. Logistical regression analysis revealed that the cat breeding history of the human subjects, but not their sex or age is a significant risk factor for T. gondii seropositivity. These findings suggest that the natural environment in Russia may be widely polluted with T. gondii oocysts shed by cats, and ingestion of these oocysts provides a major route for human infection with this parasite.  相似文献   
1000.
β‐arrestins seem to have a role in endocytosis and desensitization of somatostatin receptor subtype 2 (sst2) and could be associated with the responsiveness to somatostatin receptor ligands (SRL) in patients with acromegaly. To investigate the in vivo correlation between β‐arrestins 1 and 2 with sst2, sst5 and dopamine receptor subtype 2 (D2) expressions, and the association of β‐arrestins with response to first‐generation SRL and invasiveness in somatotropinomas. β‐arrestins 1 and 2, sst2, sst5 and D2 mRNA expressions were evaluated by quantitative real‐time RT‐PCR on tumoral tissue of 96 patients. Moreover, sst2 and sst5 protein expressions were also evaluated in 40 somatotropinomas by immunohistochemistry. Response to SRL, defined as GH <1 μg/l and normal IGF‐I levels, was assessed in 40 patients. The Knosp‐Steiner criteria were used to define invasiveness. Median β‐arrestin 1, β‐arrestin 2, sst2, sst5 and D2 mRNA copy numbers were 478; 9375; 731; 156 ; and 3989, respectively. There was a positive correlation between β‐arrestins 1 and 2 (= 0.444, < 0.001). However, no correlation between β‐arrestins and sst2, sst5 (mRNA and protein levels) or D2 was found. No association was found between β‐arrestins expression and SRL responsiveness or tumour invasiveness. Although previous data suggest a putative correlation between β‐arrestins and sst2, our data clearly indicated that no association existed between β‐arrestins and sst2, sst5 or D2 expression, nor with response to SRL or tumour invasiveness. Therefore, further studies are required to clarify whether β‐arrestins have a role in the response to treatment with SRL in acromegaly.  相似文献   
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