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31.
HSV-1 infection-mediated regulation of mRNA translation in host cells is a systematic and complicated process. Investigation of the details of this mechanism will facilitate understanding of biological variations in the viral replication process and host cells. In this study, a comparative proteomics technology platform was applied by two-dimension electrophoresis of HSV-1 infected normal human L-02 cell and control cell lysates. The observed protein spots were analyzed qualitatively and quantitatively by the PDQuest software package. A number of the different observed protein spots closely associated with cellular protein synthesis were identified by matrix-assisted laser-desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS). The expression levels of the RPLP1 protein, which is required for mRNA translation, and KHSRP protein, which is involved in rapid decay of mRNA, were up-regulated, whereas the expression level of RNP H2, which is involved in positive regulation on the mRNA splicing process, was down-regulated. All of these results suggest that HSV-1 infection can influence cellular protein synthesis via modulation of cellular regulatory proteins involved in RNA splicing, translation and decay, resulting in optimisation of viral protein synthesis when cellular protein synthesis is shut off Although there is need for further investigations regarding the detailed mechanisms of cellular protein control, our studies provide new insight into the targeting of varied virus signaling pathways involved in host cellular protein synthesis.  相似文献   
32.
Synthetic pyrethroids are considered as possible sub-stitutesfor some organophosphate carbamates or organochlo-rine insecticides,and have been used extensivelyfor morethantwo decades[1].Pyrethroids are preferred over otherinsecticides because of their easy degradation into non-toxic or less toxic metabolites under natural conditions.Consequently,there has recently beena dramatic increaseinthe use of pyrethroid pesticides to control insect pests.However,synthetic pyrethroids were also reported …  相似文献   
33.
This paper reports the first population ecology study of the endangered Magnolia sargentiana Rehder & Wilson (Magnoliaceae). Magnolia sargentiana is a protected species in China, but little is known about its present status in the field. In 2007 and 2008, we surveyed the population and conservation status ofM. sargentiana in the Provincial Mamize Nature Reserve and the National Meigu Dafengding Nature Reserve, Sichuan Province, southwestern China. Natural regeneration is poor because of unfavorable environmental conditions and anthropogenic disturbances. Flower buds and bark ofM. sargentiana are used in traditional Chinese medicine and their collection by local people over the period 1983-1994 has led to marked population declines. The collection of flower buds and bark is now banned, but hewing branches for firewood and grazing continues to have a negative impact on the recovery of M. sargentiana populations. To protect the species, we require a ban on hewing branches, closure of primary forests to reduce the impact of humans and ungulates, better education of local people, and increased awareness of wildlife conservation.  相似文献   
34.
Although previous studies showed that the principal oncoprotein encoded by Epstein-Barr virus, latentmembrane protein 1 (LMP1) 5 could induce the nasopharyngeal carcinoma cells in G_2/M phase increased, littleis known about the target molecules and mechanisms. The present study demonstrated that LMP1 couldinduce the accumulation of p53 protein and upregulate its transactivity in a dose dependent manner, whichresulted in the decrease of the kinase activity of cdc2/cyclin B complex and inducing arrest at G2/M phasethrough the activation of NF-κB and AP-1 signaling pathways, and the effect of NF-κB was more obviousthan that of AP-1. This study provided some significant evidence for further elucidating the molecularmechanisms that LMP1 had effects on the surveillance mechanism of cell cycle and promoting the survivalof transformed cells and tumorigenesis.  相似文献   
35.
大鼠心脏细胞条件培养基对小鼠ES细胞特性的维持   总被引:5,自引:1,他引:4  
孟国良  滕路  邹冀中  薛友纺  尚克刚 《遗传学报》2001,28(10):T001-T002
以C19-2和MESPU-13为供试细胞,用克隆测试、传代培养等方法对17种细胞的条件培养基进行了筛选,结果表明,大鼠心脏细胞的条件培养基(RH-CM)具有显著抑制小鼠ES细胞分化、维持其二倍体核型、促进ES细胞贴壁生长的作用。经RH-CM培养10代和20代的小鼠ES细胞在体内外分化能力上仍保留了原ES细胞的多方向分化潜能和特征;RH-CM也可作为小鼠ES细胞培养基的添加物,用含70%RH-CM的ES细胞培养基和小鼠胚胎原代成纤维细胞饲养层(PMEF)培养ES细胞,可长期有效地维持其未分化状态和二倍体核型。RT-PCR检测到大鼠心脏细胞有LIF mRNA表达。  相似文献   
36.
对灵芝(赤芝)进行了原生质体的形成和再生实验,研究了渗透压稳定剂、菌龄、酶解条件对原生质体分离的影响,以及渗透压稳定剂、培养基对原生质体再生的影响;另外还尝试用电穿孔法在灵芝原生质体中进行报告基因(reportgene)β-gal的转化,结果β-gal在菌丝体中有表达。 Abstract:The experiments of protoplasts preparation from Lingzhi (Ganoderma lucidum) and their regeneration were done and the effects of osmotic stabilizer,age of mycelium and lystic conditon on formation and regeneration of protoplasts were studied.The β-geo gene has been transformed into the protoplast by electroporation and the reporter gene β-gal has been expressed in the regenerated hypha.  相似文献   
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38.
高效建立129/ter、C57BL/6J小鼠胚胎干细胞系的方法学探讨   总被引:11,自引:0,他引:11  
小鼠胚胎干细胞 (ES细胞 )是从小鼠囊胚内细胞团(ICM)分离出来的、在体外培养过程中可维持未分化状态、正常二倍体核型及无限增殖能力 ,具有多能性或全能性的细胞系[1~ 3 ] 。ES细胞广泛应用于克隆动物制作、转基因动物生产、动物医学模型建立、真核细胞基因表达与调控的研究、细胞分化机制的探索、人及哺乳动物基因功能的研究以及细胞、组织、和器官的修复与移植研究。胚胎干细胞的研究和应用已成为生命科学研究的热点和前沿领域之一[4~ 8] 。自第一株 12 9小鼠ES细胞系建立以来 ,人们在生物学和医学等多个领域进行了广泛深入的…  相似文献   
39.
以往研究表明,许多成年雄性大熊猫在圈养状态下不能表达正常的社群性行为。我们设计了一个实验来研究大熊猫正常社群性行为与性情特征、展示、以及饲养管理的关系。通过调查获得大熊猫展示和饲养管理的数据,询问饲养员得知2001年繁殖季节中大熊猫的社群性行为发生频次,然后评估社群性行为能力。研究对象是分布在中国4个繁育中心的37头(12头雄性和25头雌性)成体大熊猫。通过提供新物品和气味来评估大熊猫情绪反应状况。情绪反应分为3类:畏惧、访问和访问玩耍。在有饲养员陪同玩耍的一组里,雌、雄大熊猫的"访问玩耍"的分值都较高。"畏惧"类的雌性大熊猫气味标记行为少,表达的性行为也少,并且更多地攻击接近它们的雄性,或者不理睬雄性。在繁殖季节前就接近雄性大熊猫围栏的雌性,表现出更多的气味标记行为和性行为。这些雌性的"访问玩耍"分值也高。"访问"分值高的雄性大熊猫,接近雌性的行为更多。那些与饲养员接触时间少的雄性大熊猫倾向于攻击雌性,与那些攻击性小的雄性相比,这些雄性倾向于能够接受丰富性低的环境。这些结果表明,应该采取措施减少大熊猫的畏惧,在大熊猫和饲养员之间建立积极的关系,在繁殖季节之前,增加雌性和雄性之间的熟悉程度。  相似文献   
40.
INTRODUCTIONRecombinant DNA technology is a powerful toolfor the introduction of foreign genes into longlivedperennials and fOr fundamelltal studies of gene expression. Using such techniques, we can overcomethe difficulties associated with the breeding of a long-lived perennial. At present, although considerablereseaxch effort has been devoted to the genetic en-gineering of fOrest trees, it has lagged behind ad-vances made in herbaceous crops due both to eco-nomics and the recalcitrant n…  相似文献   
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