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Crop improvement is a multifaceted micro-evolutionary process, involving changes in breeding approaches, planting configurations and consumption preferences of human beings. Recent research has started to identify the specific genes or genomic regions correlate to improved agronomic traits, however, an apparent blank between the genetic structure of crop elite varieties and their improving histories in diverse modern breeding programs is still in existence. Foxtail millet (Setaria italica) was one of the earliest cereal crops to be domesticated and served as a staple crop for early civilizations in China, where it is still widely grown today. In the present trial, a panel of foxtail millet elite varieties, which were released in the last sixty years in different geographical regions of China, was characterized using microsatellite markers (SSRs). A clear separation of two subpopulations corresponding to the two eco-geographical regions of foxtail millet production in China was identified by the dataset, which also indicated that in more recently released elite varieties, large quantities of accessions have been transferred from spring-sowing to summer-sowing ecotypes, likely as a result of breeding response to planting configurations. An association mapping study was conducted to identify loci controlling traits of major agronomic interest. Furthermore, selective sweeps involved in improvement of foxtail millet were identified as multi-diverse minor effect loci controlling different agronomic traits during the long-term improvement of elite varieties. Our results highlight the effect of transition of planting configuration and breeding preference on genetic evolvement of crop species.  相似文献   
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Neonatal hypoxic-ischemic brain damage (HIBD) is one of the leading causes of neonatal mortality and permanent neurological disability worldwide and the effective treatment strategies are not yet available. It has been demonstrated that Chitosan oligosaccharide (COS) exerts protective effect in vitro ischemic brain injury. However, no information is available on possible effects of COS on neonatal HIBD. To investigate the hypothesis of the potential neuroprotective effect of COS on the brain injury due to HIBD, 7-day-old Sprague–Dawley rats were treated with left carotid artery ligation followed by exposure to 8% oxygen (balanced with nitrogen) for 2.5 h at 37?°C. After COS treatment, the cerebral damage was measured by behavior tasks, 2,3,5-triphenyltetrazolium chloride(TTC), Hematoxyline-Eosin(HE), Nissl and Fluoro-Jade B(FJB)staining. In addition, the oxidative stress were assayed with ipsilateral hemisphere homogenates. Immunofluorescence staining were used to examine the activation of the astrocyte and microglia. Expression of inflammatory-related proteins were analyzed by western-blot analysis. In this study we found that administration of COS ameliorated early neurological reflex behavior, significantly reduce brain infarct volume and attenuated neuronal cell injury and degeneration. Furthermore, COS markedly decreased the level of MDA, lactic acid and increased SOD, GSH-Px and T-AOC. COS attenuated hypoxic-ischemic induced up-regulation of expressions of interleukin-1β (IL-1β), tumor necrosis factor alpha (TNF-α), meanwhile it dramatically increased the interleukin-10 (IL-10). These results suggest that COS exerts neuroprotection on hypoxic-ischemic brain damage in neonatal rats, it implies COS might be a potential therapeutic for the treatment of HIBD.  相似文献   
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Diesel engine exhaust (DEE) was found to induce lipid peroxidation (LPO) in animal exposure studies. LPO is a class of oxidative stress and can be reflected by detecting the levels of its production, such as malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), and etheno-DNA adducts including 1,N6-etheno-2′-deoxyadenosine (?dA) and 3,N4-etheno-2′-deoxycytidine (?dC). However, the impact of DEE exposure on LPO has not been explored in humans. In this study, we evaluated urinary MDA, 4-HNE, ?dA, and ?dC levels as biomarkers of LPO among 108 workers with exclusive exposure to DEE and 109 non-DEE-exposed workers. Results showed that increased levels of urinary MDA and ?dA were observed in subjects occupationally exposed to DEE before and after age, body mass index (BMI), smoking status, and alcohol use were adjusted (all p?p?p?相似文献   
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Previous studies found that the activity of Sortase A, a bacterial surface protein from Staphylococcus aureus, was inhibited by curcumin and its analogues. To explore this inhibitory mechanism, Sortase A and its inhibitors in complex systems were studied by molecular docking, molecular modelling, binding energy decomposition calculation and steered molecular dynamics simulations. Energy decomposition analysis indicated that PRO-163, LEU-169, GLN-172, ILE-182 and ILE-199 are key residues in Sortase A-inhibitor complexes. Furthermore, interactions between the methoxyl group on the benzene ring in the conjugated molecule (curcumin, demethoxycurcumin, bisdemethoxycurcumin) and VAL-168, LEU-169 and GLN-172 induce the inhibitory activity based on the energy decomposition and distance analyses between the whole residues and inhibitors. However, because of its coiled structure, the non-conjugated molecule, tetrahydrocurcumin, with key residues in the binding sites of Sortase A, interacted weakly with SrtA, leading to the loss of inhibitory activity. Based on these results, the methoxyl group on the benzene ring in the conjugated molecule largely influenced the inhibitory activity of the Sortase A inhibitors.  相似文献   
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Increasing reports suggest that deregulated microRNAs (miRNAs) might provide novel therapeutic targets for cancers. However, the expression and function of miR-300 in osteosarcoma is still unknown. In our study, we found that the expression of miR-300 was up-regulated in osteosarcoma tissues and cells compared with paired adjacent non-tumor bone tissues and osteoblastic cells using RT-qPCR. The enforced expression of miR-300 could promote cell proliferation, invasion and epithelial-mesenchymal transition (EMT). Moreover, we identified that bromodomain-containing protein 7 (BRD7), a new tumor suppressor gene, was a direct target of miR-300. Ectopic expression of BRD7 could significantly inhibit miR-300-promoted proliferation, invasion and EMT. Therefore, our results identify an important role for miR-300 in osteosarcoma through regulating BRD7 expression.  相似文献   
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