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Embryos of most fish develop externally and are exposed to an aquatic environment full of potential pathogens, whereas they have little or only limited ability to mount an efficient and protective response. How fish embryos survive pathogenic attacks remains poorly defined. Here we demonstrate that the maternal immunization of female zebrafish with formalin-killed Aeromonas hydrophila causes a significant increase in C3 and Bf contents in the mother, a corresponding rise in the offspring, and induces a remarkable increase in the hemolytic activities in both the mother and offspring. In addition, the embryos derived from the immunized mother are significantly more tolerant to A. hydrophila challenge than those from the unimmunized fish, and blocking C3 and Bf activities by injection of the antibodies against C3 and Bf into the embryos render them more susceptible to A. hydrophila. These results clearly show that the protection of zebrafish embryos against A. hydrophila can be achieved by the maternally-transferred immunity of the complement system operating via the alternative pathway. This appears to be the first report providing in vivo evidences for the protective role of the alternative complement components in the early embryos of zebrafish, paving the way for insights into the in vivo function of other maternally-transferred factors in fish.  相似文献   
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In human pathological conditions, the acidification of local environment is a frequent feature, such as tumor and inflammation. As the pH of microenvironment alters, the functions of immune cells are about to change. It makes the extracellular acidification a key modulator of innate immunity. Here we detected the impact of extracellular acidification on neutrophil apoptosis and functions, including cell death, respiratory burst, migration and phagocytosis. As a result, we found that under the acid environment, neutrophil apoptosis delayed, respiratory burst inhibited, polarization augmented, chemotaxis differed, endocytosis enhanced and bacteria killing suppressed. These findings suggested that extracellular acidification acts as a key regulator of neutrophil apoptosis and functions.  相似文献   
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Human plasma is dominated by high‐abundance proteins which severely impede the detection of low‐abundance proteins. Unfortunately, now there is no efficient method for large‐scale depletion of high‐abundance proteins in human plasma. In this study, we developed a new strategy, strong anion exchange (SAX)/RP 2D LC system, which has potential for large‐scale depletion of high‐abundance proteins in human plasma. Separation gradients of the system were optimized to ensure an extensive separation of plasma proteins. Plasma was fractionated into 67 fractions by SAX. All these fractions were subjected a thorough separation by the 2D RPLC and 66 peaks with high UV absorption (>20 mAU) at 215 nm were collected. Proteins in these peaks were identified by LC‐MS/MS analysis. Results showed that 83 proteins could be identified in these peaks, 68 among them were reported to be high‐ or middle‐abundance proteins in plasma. All these proteins had definite retention times and were mapped in the 2D SAX‐RP system, which resulted in accurate depletion of high‐abundance proteins with ease. Our studies provide a convenient and effective method for large‐scale depletion of high‐abundance proteins and in‐depth research in human plasma proteomics.  相似文献   
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Coupling of biodegradable corncob and plastic carrier was optimized in continuous-flow solid-phase denitrification systems for enhancing simultaneously removal of nitrogen and organics in agricultural runoff. In compared with preposition of plastic carriers and mixed distribution method, it was demonstrated that the preposition of corncobs simultaneously enhanced nitrate (6.64 ± 1.35 mg L?1 day ?1) and organics removal (6.33 ± 1.44 mg L?1 day?1) at a hydraulic retention time (HRT) of 6 h. The operation performance could be further enhanced with extension of HRT to 12 h. The dominant genera found in corncob were denitrifiers for nitrate reduction (Bosea, Simplicispira, Desulfovibrio, Klebsiella, etc.) and fermentative bacteria (Pleomorphomonas, Actinotalea, Opitutus, Cellulomonas, Bacteroides, etc.) responsible for corncob degrading to simple organics for other denitrifiers. However, much lower and different denitrifiers abundances (Bradyrhizobium, Acinetobacter, Bacillus, etc.) exhibited on plastic filler than those of corncob. It well explained that the biofilm on plastic carrier was mainly related with organics removal while the biofilm on corncobs inclined to effectively remove nitrate, and simultaneous removal of nitrogen and organics could be achieved in coupling carriers system with preposition of biodegradable corncob.  相似文献   
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An emigrant worker returning from Southeast Asia triggered the outbreak of a DF epidemic in Zhejiang province, China, in October, 2004. Eighty‐three cases, mainly young and middle‐aged people between 20 and 50 (78.3%), were reported in the area of Cixi. There were no obvious occupational patterns. The majority of cases were female, with a sex ratio of 1:1.86 (m:f). The dengue virus (DENV) strains from the epidemic area were isolated and identified as DENV‐1, which belongs to Asian strain 1. According to the epidemiological investigation, the incidence of DF had no relationship to temperature, humidity, or precipitation, and the Breteau index of larvae showed a clear relationship only with the House Index and Container Index. Recent dengue problems in the town have been associated with the complex social factors and hygienic conditions for endemic villagers and immigrant workers. Some hygienic measures should be taken by the local government to reduce the risk of mosquito‐borne disease. These measures should aim to eliminate the breeding sites of the vector Aedes albopictus in indoor and outdoor containers filled with rainwater and thus reducing the risk of DF transmission.  相似文献   
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水稻粒长QTL定位与主效基因的遗传分析   总被引:1,自引:0,他引:1  
该研究利用短粒普通野生稻矮杆突变体和长粒栽培稻品种KJ01组配杂交组合F_1,构建分离群体F_2;并对该群体粒长进行性状遗传分析,利用平均分布于水稻的12条染色体上的132对多态分子标记对该群体进行QTL定位及主效QTLs遗传分析,为进一步克隆新的主效粒长基因奠定基础,并为水稻粒形育种提供理论依据。结果表明:(1)所构建的水稻杂交组合分离群体F_2的粒长性状为多基因控制的数量性状。(2)对543株F_2分离群体进行QTL连锁分析,构建了控制水稻粒长的连锁遗传图谱,总长为1 713.94 cM,共检测出24个QTLs,只有3个表现为加性遗传效应,其余位点均表现为遗传负效应。(3)检测到的3个主效QTLs分别位于3号染色体的分子标记PSM379~RID24455、RID24455~RM15689和RM571~RM16238之间,且三者对表型的贡献率分别为54.85%、31.02%和7.62%。(4)在标记PSM379~RID24455之间已克隆到的粒长基因为该研究新发现的主效QTL位点。  相似文献   
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