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91.
92.
The La antigen (SS-B) associates with a wide variety of cellular and viral RNAs to affect gene expression in multiple systems. We show that La is the major cellular protein found to be associated with the abundant 44-nucleotide viral leader RNA (leRNA) early after infection with respiratory syncytial virus (RSV), a nonsegmented negative-strand RNA virus. Consistent with this, La redistributes from the nucleus to the cytoplasm in RSV-infected cells. Upon RNA interference knockdown of La, leRNA is redirected to associate with the RNA-binding protein RIG-I, a known activator of interferon (IFN) gene expression, and this is accompanied by the early induction of IFN mRNA. These results suggest that La shields leRNA from RIG-I, abrogating the early viral activation of type I IFN. We mapped the leRNA binding function to RNA recognition motif 1 of La and showed that while wild-type La greatly enhanced RSV growth, a La mutant defective in RSV leRNA binding also did not support RSV growth. Comparative studies of RSV and Sendai virus and the use of IFN-negative Vero cells indicated that La supports the growth of nonsegmented negative-strand RNA viruses by both IFN suppression and a potentially novel IFN-independent mechanism.  相似文献   
93.
Seth  J. K.  Barik  T. K.  Mishra  S. S. 《Journal of Ichthyology》2019,59(2):266-270
Journal of Ichthyology - The paper reports Gazza dentex (Valenciennes) collected from Gopalpur-on-Sea, Odisha as the first report of this species from Odisha coast, India. This is confirmed by...  相似文献   
94.
The aim of the present study was investigation of the effects of fly ash and mining soil on growth and antioxidant protection of two cultivars of Indian wild rice (Oryza nivara and Oryza rufipogon) for possible phytoremediation and restoration of metal-contaminated site. In this study, Indian wild rice showed significant changes in germination, growth, and biochemical parameters after exposure to different ratio of fly ash and mining soil with garden soil. There was significant reduction of germination, fresh weight, dry weight, leaf chlorophyll content, leaf area, Special Analysis Device Chlorophyll (SPAD) Index, proteins, and activities of antioxidant enzymes in both cultivars of the wild rice grown in 100% fly ash and mining soil compared to the plants grown in 100% garden soil. Results from this study showed that in both cultivars of wild rice, all growth and antioxidant parameters increased when grown in 50% fly ash and mining soil. Taken together, Indian wild rice has the capacity to tolerate 50% of fly ash and mining soil, and can be considered as a good candidate for possible phytoremediation of contaminated soils.  相似文献   
95.
Textile effluent is generally complicated to manage because of its extremely noxious and recalcitrant coloured compositions. Mycoremediation is an extensively used strategy for the competent degradation of hazardous pollutants present in textile effluent. Fungus could be immobilized in synthetic or natural matrices. The current study shows the decolourization of the textile effluent by 85·5 and 98·5% within 6 h using suspended and immobilized fungus, Geotrichum candidum with optimized parameters like inoculum size (5%), pH (4·5), and temperature (30°C). To maintain a high biomass of fungal population and enhance the retention of fungal strain in the contaminated sites, the fungi need to be immobilized. Hence, the fungus was immobilized naturally onto the selected inert support that is, coconut fibres by the means of adsorption, where they grew as active films on the fibres after being grown in the culture broth. The optimized process parameters of inoculum size, fibre quantity and agitation speed for immobilized G. candidum were 5%, 2·2 g l−1 of effluent and 100 rev min−1 respectively. High level of laccase (22 and 25 U l−1 in suspended and immobilized fungal cells treatment respectively) was observed during the process of decolourization and it was found that decolourization was directly proportional to the laccase activity. The UV–vis, FTIR, 1H NMR and GC-MS analyses of treated textile industrial wastewater revealed the degradation of toxic pollutants in the textile effluent and formation of lower molecular weight intermediates. The study revealed a higher efficacy of immobilized G. candidum in comparison to suspended fungal culture, employing ligninolytic enzyme laccase, which catalyzes the degradation/transformation of aromatic dyes in the textile effluent thus decolourizing it.  相似文献   
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BackgroundThe objective of this study is to determine the impact of intensity modulated proton therapty (IMPT) optimization techniques on the proton dose comparison of commercially available magnetic resonance for calculating attenuation (MRCA T) images, a synthetic computed tomography CT (sCT) based on magnetic resonance imaging (MRI) scan against the CT images and find out the optimization technique which creates plans with the least dose differences against the regular CT image sets.Material and methodsRegular CT data sets and sCT image sets were obtained for 10 prostate patients for the study. Six plans were created using six distinct IMPT optimization techniques including multi-field optimization (MFO), single field uniform dose (SFUD) optimization, and robust optimization (RO) in CT image sets. These plans were copied to MRCA T, sCT datasets and doses were computed. Doses from CT and MRCA T data sets were compared for each patient using 2D dose distribution display, dose volume histograms (DVH), homogeneity index (HI), conformation number (CN) and 3D gamma analysis. A two tailed t-test was conducted on HI and CN with 5% significance level with a null hypothesis for CT and sCT image sets.ResultsAnalysis of ten CT and sCT image sets with different IMPT optimization techniques shows that a few of the techniques show significant differences between plans for a few evaluation parameters. Isodose lines, DVH, HI, CN and t-test analysis shows that robust optimizations with 2% range error incorporated results in plans, when re-computed in sCT image sets results in the least dose differences against CT plans compared to other optimization techniques. The second best optimization technique with the least dose differences was robust optimization with 5% range error.ConclusionThis study affirmatively demonstrates the impact of IMPT optimization techniques on synthetic CT image sets dose comparison against CT images and determines the robust optimization with 2% range error as the optimization technique which gives the least dose difference when compared to CT plans.  相似文献   
98.
目的减少Finn CA于1984年首次报道的小鼠月经模型的观察时间点,以期为月经生理学研究提供一种较廉价且易操作的月经模型。方法应用成年雌性去势C57BL/6小鼠,给予续贯性激素处理,最末次激素处理后4~6h,实验组小鼠宫腔内注射花生油以诱导子宫内膜蜕膜化反应,对照组小鼠给予同样激素处理但无宫腔油剂注射。分别于油剂处理后31~35h(T3组)、56~70h(T4组)处死小鼠,称量子宫湿重,制作H&E组织切片,运用图像分析软件CAST2,计算全子宫横截面积(TUA)与子宫内膜横截面积(EA)。结果H&E染色子宫组织切片示在单纯雌激素作用下宫内膜呈单层立方上皮,核浆比较高,内膜基质疏松;雌孕激素联合处理后,分泌细胞易见,腺腔内可见分泌物。激素撤退后实验组T3观察到子宫内膜剥离,T4组示子宫内膜修复。对照组子宫内膜始终完整。子宫湿重在激素撤退后,实验组下降较慢。激素撤退后实验组T3的TUA继续上升而EA则维持原水平,T4组TUA与EA均明显下降。结论此模型在子宫内膜剥落期和早期修复期组织学特征与人类子宫内膜有一定的相似性。  相似文献   
99.
Apoptosis is characterized by DNA strand breaks with a 3'-OH terminus, which are analyzed by terminal deoxy(d)-UTP nick end labeling (TUNEL). Proteinase K digestion is thought to be an essential step in the TUNEL procedure. The effects of decalcifying reagents on general staining and the TUNEL assay for cartilage sections are largely unknown. The effects of these reagents on retention and integrity of DNA in chondrocytes have not been described until now. We evaluated the effects of various decalcifying solutions, including 10% EDTA, 10% citric acid, 5% trichloroacetic acid, 5% acetic acid and a commercial hydrochloric acid-based reagent, on general cartilage staining and the TUNEL assay for cartilage. The effects of proteinase K on nucleus preservation were also examined. Decalcification with 10% EDTA gave the best result for general cartilage staining. Chondrocyte DNA was retained and intact after using this reagent. Decalcification with 10% EDTA is also the safest method of decalcification if the TUNEL assay is applied to cartilage. Proteinase K digestion may have adverse effects on nucleus preservation in cartilage. Awareness of these effects is important whenever the TUNEL assay is applied.  相似文献   
100.
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