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Holocarboxylase synthetase (HCS) plays an essential role in catalyzing the biotinylation of carboxylases and histones. Biotinylated carboxylases are important for the metabolism of glucose, lipids and leucine; biotinylation of histones plays important roles in gene regulation and genome stability. Recently, we reported that HCS activity is partly regulated by subcellular translocation events and by miR-539. Here we tested the hypothesis that the HCS 3′-untranslated region (3′-UTR) contains binding sites for miR other than miR-539. A binding site for miR-153 was predicted to reside in the HCS 3′-UTR by using in silico analyses. When miR-153 site was overexpressed in transgenic HEK-293 human embryonic kidney cells, the abundance of HCS mRNA decreased by 77% compared with controls. In silico analyses also predicted three putative cytosine methylation sites in two miR-153 genes; the existence of these sites was confirmed by methylation-sensitive polymerase chain reaction. When cytosines were demethylated by treatment with 5-aza-2′-deoxycytidine, the abundance of miR-153 increased by more than 25 times compared with untreated controls, and this increase coincided with low levels of HCS and histone biotinylation. Together, this study provides novel insights into the mechanisms of novel epigenetic synergies among folate-dependent methylation events, miR and histone biotinylation.  相似文献   
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Verticillium wilt caused by soilborne fungus Verticillium dahliae could significantly reduce cotton yield. Here, we cloned a tomato Ve homologous gene, Gbve1, from an island cotton cultivar that is resistant to Verticillium wilt. We found that the Gbve1 gene was induced by V. dahliae and by phytohormones salicylic acid, jasmonic acid, and ethylene, but not by abscisic acid. The induction of Gbve1 in resistant cotton was quicker and stronger than in Verticillium-susceptible upland cotton following V. dahliae inoculation. Gbve1 promoter-driving GUS activity was found exclusively in the vascular bundles of roots and stems of transgenic Arabidopsis. Virus-induced silencing of endogenous genes in resistant cotton via targeting a fragment of the Gbve1 gene compromised cotton resistance to V. dahliae. Furthermore, we transformed the Gbve1 gene into Arabidopsis and upland cotton through Agrobacterium-mediated transformation. Overexpression of the Gbve1 gene endowed transgenic Arabidopsis and upland cotton with resistance to high aggressive defoliating and non-defoliating isolates of V. dahliae. And HR-mimic cell death was observed in the transgenic Arabidopsis. Our results demonstrate that the Gbve1 gene is responsible for resistance to V. dahliae in island cotton and can be used for breeding cotton varieties that are resistant to Verticillium wilt.  相似文献   
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Doubled haploid (DH) populations are useful to scientists and breeders in both crop improvement and basic research. Current methods of producing DHs usually need in vitro culture for extracting haploids and chemical treatment for chromosome doubling. This report describes a simple method for synthesizing DHs (SynDH) especially for allopolyploid species by utilizing meiotic restitution genes. The method involves three steps: hybridization to induce recombination, interspecific hybridization to extract haploids, and spontaneous chromosome doubling by selfing the interspecific F1s. DHs produced in this way contain recombinant chromosomes in the genome(s) of interest in a homogeneous background. No special equipment or treatments are involved in the DH production and it can be easily applied in any breeding and/or genetic program. Triticum turgidum L. and Aegilops tauschii Coss, the two ancestral species of common wheat (Triticum aestivum L.) and molecular markers were used to demonstrate the SynDH method.  相似文献   
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采用常规压片法,对风毛菊属(Saussurea)5种植物的染色体数目和核型类型进行分析。结果表明:大耳叶风毛菊(S.macrota)核型公式为2n=2x=26=10m+12sm+4st,属2A型;长梗风毛菊(S.dolichopoda)核型公式为2n=2x=26=14m+8sm+4st,属2A型;川陕风毛菊(S.licentiana)核型公式为2n=2x=28=12m+16sm,属2B型;杨叶风毛菊(S.populifolia)核型公式为2n=2x=28=6m+18sm+4st,属2B型;尾叶风毛菊(S.caudata)核型公式为2n=2x=30=14m+14sm+2st,属2A型。这5种风毛菊属植物中,除大耳叶风毛菊染色体数目和核型类型与前人报道的一致外,其余4种植物的染色体数目和核型类型均为首次报道,并在川陕风毛菊中发现1对B染色体。  相似文献   
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ObjectiveTo compare the effectiveness and safety of regional anesthesia (RA) and general anesthesia (GA) for percutaneous nephrolithotomy (PNL).ResultsEight randomized controlled trials (RCTs) and six non-randomized controlled trials (nRCTs) involving 2270 patients were included. Patients receiving RA were associated with shorter operative time (−6.22 min; 95%CI, −9.70 to −2.75; p = 0.0005), lower visual analgesic score on the first and third postoperative day (WMD, −2.62; 95%CI, −3.04 to −2.19; p < 0.00001 WMD, −0.38; 95%CI, −0.58 to −0.18; p = 0.0002), less analgesic requirements (WMD, −59.40 mg; 95%CI, −78.39 to −40.40; p<0.00001), shorter hospitalization (WMD, −0.36d; 95%CI, −0.66 to −0.05; p = 0.02), less blood transfusion (RR, 0.61; 95%CI, 0.41 to 0.93; p = 0.02), fewer modified Clavion-Dindo Grade II (RR, 0.56; 95%CI, 0.37 to 0.83; p = 0.005), Grade III or above postoperative complications (RR, 0.51; 95%CI, 0.33 to 0.77; p = 0.001), and potential benefits of less fever (RR, 0.79; 95%CI, 0.61 to 1.02; p = 0.07), nausea or vomiting (RR, 0.54; 95%CI, 0.20 to 1.46; p = 0.23), whereas more intraoperative hypotension (RR, 3.13; 95%CI, 1.76 to 5.59; p = 0.0001) when compared with patients receiving GA. When nRCTs were excluded, most of the results were stable but the significant differences were no longer detectable in blood transfusion, Grade II and more severe complications. No significant difference in the total postoperative complications and stone-free rate were found.ConclusionsCurrent evidence suggests that both RA and GA can provide safe and effective anesthesia for PNL in carefully evaluated and selected patients. Each anesthesia technique has its own advantages but some aspects still remain unclear and need to be explored in future studies.  相似文献   
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