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61.
The breakthrough in derivation of human‐induced pluripotent stem cells (hiPSCs) provides an approach that may help overcome ethical and allergenic challenges posed in numerous medical applications involving human cells, including neural stem/progenitor cells (NSCs). Considering the great potential of NSCs in targeted cancer gene therapy, we investigated in this study the tumor tropism of hiPSC‐derived NSCs and attempted to enhance the tropism by manipulation of biological activities of proteins that are involved in regulating the migration of NSCs toward cancer cells. We first demonstrated that hiPSC‐NSCs displayed tropism for both glioblastoma cells and breast cancer cells in vitro and in vivo. We then compared gene expression profiles between migratory and non‐migratory hiPSC‐NSCs toward these cancer cells and observed that the gene encoding neuronal nitric oxide synthase (nNOS) was down‐regulated in migratory hiPSC‐NSCs. Using nNOS inhibitors and nNOS siRNAs, we demonstrated that this protein is a relevant regulator in controlling migration of hiPSC‐NSCs toward cancer cells, and that inhibition of its activity or down‐regulation of its expression can sensitize poorly migratory NSCs and be used to improve their tumor tropism. These findings suggest a novel application of nNOS inhibitors in neural stem cell‐mediated cancer therapy.  相似文献   
62.
The potential for using agricultural and industrial by-products as substrate for the production of the edible mushroom, Auricularia polytricha, was evaluated using several formulations of selected palm oil wastes mixed with sawdust and further supplemented with selected nitrogen sources. The best substrate formulations were sawdust (SD) mixed with oil palm frond (OPF; 90:10) added with 15 % spent grain (SG) and sawdust mixed with empty fruit bunch (EFB; 50:50) added with 10 % spent grain (SG) with mycelia growth rate of 8 mm/day and 7 mm/day respectively. These two substrate formulations were then subjected to different moisture content levels (65 %, 75 % and 85 %). Highest total fresh sporophore yield at 0.43 % was obtained on SD?+?OPF (90:10)?+?15 % SG at 85 % moisture content, followed closely by SD?+?EFB (50:50)?+?10 % SG with 0.40 % total yield, also at 85 % moisture content. Each of the substrate formulations at 85 % moisture content gave the highest biological efficiency (BE) at 288.9 % and 260.7 %, respectively. Both yield and biological efficiency of A. polytricha on these two formulations were almost three times higher when compared to sawdust substrate alone, thus proving the potential of these formulations to improve yield of this mushroom.  相似文献   
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A series of 1,3,4-oxadiazole derivatives containing 1,4-benzodioxan moiety (7a7q) have been designed, synthesized and evaluated for their antitumor activity. Most of the synthesized compounds were proved to have potent antitumor activity and low toxicity. Among them, compound 7a showed the most potent biological activity against Human Umbilical Vein Endothelial cells, which was comparable to the positive control. The results of apoptosis and flow cytometry (FCM) demonstrated that compound 7a induce cell apoptosis by the inhibition of MetAP2 pathway. Molecular docking was performed to position compound 7a into MetAP2 binding site in order to explore the potential target.  相似文献   
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Objectives : A twin‐based comparative study on the genetic influences in metabolic endophenotypes in two populations of substantial ethnic, environmental, and cultural differences was performed. Design and Methods : Data on 11 metabolic phenotypes including anthropometric measures, blood glucose, and lipids levels as well as blood pressure were available from 756 pairs of Danish twins (309 monozygotic and 447 dizygotic twin pairs) with a mean age of 38 years (range: 18‐67) and from 325 pairs of Chinese twins (183 monozygotic and 142 dizygotic twin pairs) with a mean age of 40.5 years (range: 18‐69). Twin modeling was performed on full and nested models with the best fitting models selected. Results : Heritability estimates were compared between Danish and Chinese samples to identify differential genetic influences on each of the phenotypes. Except for hip circumference, all other body measures exhibited similar heritability patterns in the two samples with body weight showing only a slight difference. Higher genetic influences were estimated for fasting blood glucose level in Chinese twins, whereas the Danish twins showed more genetic regulation over most lipids phenotypes. Systolic blood pressure was more genetically controlled in Danish than in Chinese twins. Conclusions : Metabolic endophenotypes show disparity in their genetic determinants in populations under distinct environmental conditions.  相似文献   
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The functional region of interest (fROI) approach has increasingly become a favored methodology in functional magnetic resonance imaging (fMRI) because it can circumvent inter-subject anatomical and functional variability, and thus increase the sensitivity and functional resolution of fMRI analyses. The standard fROI method requires human experts to meticulously examine and identify subject-specific fROIs within activation clusters. This process is time-consuming and heavily dependent on experts’ knowledge. Several algorithmic approaches have been proposed for identifying subject-specific fROIs; however, these approaches cannot easily incorporate prior knowledge of inter-subject variability. In the present study, we improved the multi-atlas labeling approach for defining subject-specific fROIs. In particular, we used a classifier-based atlas-encoding scheme and an atlas selection procedure to account for the large spatial variability across subjects. Using a functional atlas database for face recognition, we showed that with these two features, our approach efficiently circumvented inter-subject anatomical and functional variability and thus improved labeling accuracy. Moreover, in comparison with a single-atlas approach, our multi-atlas labeling approach showed better performance in identifying subject-specific fROIs.  相似文献   
69.
Returning straw to deep soil layers by using a deep-ditching-ridge-ploughing method is an innovative management practice that improves soil quality by increasing the soil organic carbon (SOC) content. However, the optimum quantity of straw return has not been determined. To solve this practical production problem, the following treatments with different amounts of corn straw were investigated: no straw return, CK; 400 kg ha-1 straw, S400; 800 kg ha-1 straw, S800; 1200 kg ha-1 straw, S1200; and 1600 kg ha-1 straw, S1600. After straw was returned to the soil for two years, the microbial biomass C (MBC), easily oxidized organic C (EOC), dissolved organic C (DOC) and light fraction organic C (LFOC) content were measured at three soil depths (0–10, 10–20, and 20–40 cm). The results showed that the combined application of 800 kg ha-1 straw significantly increased the EOC, MBC, and LFOC contents and was a suitable agricultural practice for this region. Moreover, our results demonstrated that returning straw to deep soil layers was effective for increasing the SOC content.  相似文献   
70.
3-Hydroxy-4(4H)-pyridone (3,4-DHP), a degraded product of mimosine [β-[N-(3-hydroxy-4-oxypyridyl)]-α-aminopropionic acid], is known to cause goiters, loss of hair, and infertility in animals, but limits of 3,4-DHP on separation and purification have prevented efforts on investigating other toxicity and biological properties of 3,4-DHP. By this study, a novel and simple isolation of 3,4-DHP was developed either from Leucaena leaves using an ion-exchanged resin or mimosine degraded in high temperature (110°C, 6?h). The inhibition of mimosine on the growth of barnyardgrass was approximately fourfold higher (IC50?=?0.04?mg?g?1) than that of 3,4-DHP (IC50?=?0.15?mg?g?1). In general, the antifungal activity of mimosine is much stronger than that of 3,4-DHP, but it differs depending on the kind of fungi. The 1,1-diphyenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of 3,4-DHP, in contrast with the growth inhibitory activity, is about fourfold stronger [EC50?=?2.4?mg?g?1 gallic acid equivalent (GAE)] than that of mimosine [EC50?=?10.3?mg?g?1 GAE]. This study is the first to report on the herbicidal, antifungal, and antioxidant activities of 3,4-DHP.  相似文献   
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