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标准号: NF V08-204-2011

摘要： La présente Norme internationale définit les termes relatifs à la détection de micro-organismes pathogènes présents dans les aliments et les extraits obtenus à partir de ces aliments, en faisant appel à la réaction de polymérisation en chaîne (PCR). La présente Norme internationale spécifie également les exigences relatives à l'amplification et à la détection des séquences d'acide nucléique (ADN ou ARN après transcription inverse) par une PCR en temps ré*** exigences minimales spécifiées dans la présente Norme internationale servent de base pour l'obtention de résultats comparables et reproductibles au sein d'un laboratoire et dans des laboratoires diffé*** présente Norme internationale peut également être utilisée, par exemple, pour la détection de microorganismes pathogènes d'origine alimentaire dans des prélèvements environnementaux ainsi que dans les aliments pour animaux.

关键词： 东江干流   底栖动物   水质   生物评价  

摘要： 2009年7月14-30日对东江设43个点位进行调查,共采到底栖动物28种,密度为26～2 167个/m2;其中,昆虫纲16种,软体动物门6种,寡毛纲动物5种,蛭纲1种。调查发现,所有底栖动物中,出现频率最高的是管水蚓属(Aulodrilus sp.),为53.5%。根据已有水质生物学评价标准并结合水体理化指标,对比5种生物指数后,选取生物学污染指数(BPI)作为评价东江干流水质的地方性生物指数。水质生物学评价结果显示,东江干流水质总体良好,但与20世纪80年代相比,底栖生物的种类、优势种和数量均有较大差异,从水质生物学的角度考虑,水体质量有所下降。

关键词： devolution of telomeres   immortalization   telomerase   replicative aging   senescence  

摘要： Progressive telomere shortening from cell division (replicative aging) provides a barrier for human tumor progression. This program is not conserved in laboratory mice, which have longer telomeres and constitutive telomerase. Wild species that do/do not use replicative aging have been reported, but the evolution of different phenotypes and a conceptual framework for understanding their uses of telomeres is lacking. We examined telomeres/telomerase in cultured cells from > 60 mammalian species to place different uses of telomeres in a broad mammalian context. Phylogeny-based statistical analysis reconstructed ancestral states. Our analysis suggested that the ancestral mammalian phenotype included short telomeres (< 20 kb, as we now see in humans) and repressed telomerase. We argue that the repressed telomerase was a response to a higher mutation load brought on by the evolution of homeothermy. With telomerase repressed, we then see the evolution of replicative aging. Telomere length inversely correlated with lifespan, while telomerase expression co-evolved with body size. Multiple independent times smaller, shorter-lived species changed to having longer telomeres and expressing telomerase. Trade-offs involving reducing the energetic/cellular costs of specific oxidative protection mechanisms (needed to protect < 20 kb telomeres in the absence of telomerase) could explain this abandonment of replicative aging. These observations provide a conceptual framework for understanding different uses of telomeres in mammals, support a role for human-like telomeres in allowing longer lifespans to evolve, demonstrate the need to include telomere length in the analysis of comparative studies of oxidative protection in the biology of aging, and identify which mammals can be used as appropriate model organisms for the study of the role of telomeres in human cancer and aging.

关键词： Animal   pancreas   tumor   adenocarcinoma   metastasis   lymph node   cytologic diagnosis   endoscopic ultrasound  

摘要： The abstract is available at the Clinical pancreatic disorder I: Acute pancreatitis.

关键词： Zinc   Copper   Mammalian metallothioneins   Metal-thiolate clusters   Neurodegenerative diseases  

摘要： Metallothioneins (MTs) are a class of ubiquitously occurring low molecular mass, cysteine- and metal-rich proteins containing sulfur-based metal clusters formed with Zn(II), Cd(II), and Cu(I) ions. In mammals, four distinct MT isoforms designated MT-1 through MT-4 exist. The first discovered MT-1/MT-2 are widely expressed isoforms, whose biosynthesis is inducible by a wide range of stimuli, including metals, drugs, and inflammatory mediators. In contrast, MT-3 and MT-4 are noninducible proteins, with their expression primarily confined to the central nervous system and certain squamous epithelia, respectively. MT-1 through MT-3 have been reported to be secreted, suggesting that they may play different biological roles in the intracellular and extracellular space. Recent reports established that these isoforms play an important protective role in brain injury and metal-linked neurodegenerative diseases. In the postgenomic era, it is becoming increasingly clear that MTs fulfill multiple functions, including the involvement in zinc and copper homeostasis, protection against heavy metal toxicity, and oxidative damage. All mammalian MTs are monomeric proteins, containing two metal-thiolate clusters. In this review, after a brief summary of the historical milestones of the MT-1/MT-2 research, the recent advances in the structure, chemistry, and biological function of MT-3 and MT-4 are discussed.

关键词： VEGF165   转染   筛选   表达   鉴定   活性  

摘要： 目的构建真核表达载体pcDNA3.1(+)-血管内皮生长因子(VEGF)165并在哺乳动物细胞中实现目的基因的表达,对目的蛋白进行鉴定和生物学活性分析。方法分子生物学方法将扩增的VEGF165基因克隆入真核表达载体pcDNA3.1(+),在脂质体介导下将重组质粒转染至哺乳动物细胞NIH 3T3并进行抗生素压力筛选,采用双抗夹心ELISA、SDS-PAGE和免疫印迹方法对目的蛋白在转染细胞中的特异表达进行鉴定,在血管内皮细胞ECV304上对表达产物的细胞结合活性和促增殖活性进行分析。结果构建的真核表达载体pcDNA3.1(+)-VEGF165成功转染NIH3T3,获得加压筛选的重组细胞,目的基因得到稳定表达,目的蛋白能与血管内皮细胞ECV304特异结合,并具有促内皮细胞增殖活性。结论应用pcDNA3.1(+)-VEGF165载体转染的NIH 3T3细胞可稳定表达具生物学活性的VEGF165重组蛋白。

关键词： 动物   温度   基因   蛋白质   细胞膜  

摘要： 动物对环境温度的适应,会使自身的细胞内转录和表达模式发成变化,以适合环境的变化,此时它会出现新的基因开放和新蛋白因子的合成,这总的来说是动物对自身的一种保护方式。本文从基因水平、蛋白质水平、细胞膜水平等三个方面综述了动物对环境温度适应的研究概况,并讨论了动物对环境温度适应的分子生物学机制以及在进化中的意义。

关键词： Life span   life   Biological Science Disciplines   biological change   Marathons   physical performance   Exposure tolerance   malleability   East African  

摘要： The malleability of mammalian biology during early life, which carries considerable weight throughout the course of the lifespan, may contribute to the creation of a human phenotype ideal for prime physical performance. In this article, the authors consider the East African cohort of exceptional athletes that dominate marathon performance. Since entering international marathon competition in 1960, East Africans have competed at the front of the pack and now hold the top 10 men's marathon times. The authors present lines of evidence supporting that exposure to factors such as altitude and early metabolic adjustments that are inherent in East African early life exert a strong influence in later life physical performance and may collide with a genetic advantage to induce biological changes that allow for a more robust biological response to training in later life.

标准号: BS EN ISO 22118-2011

摘要： This International Standard specifies minimum requirements of performance characteristics for the detectionof nucleic acid sequences (DNA or RNA) by molecular methods. This International Standard applies to thedetection of food-borne pathogens in foodstuffs and isolates obtained from them using molecular detectionmethods based on the polymerase chain reaction (PCR).This International Standard is also applicable, for example, to the detection of food-borne pathogens inenvironmental samples and in animal feeding *** Because of the rapid progress in this field, the examples given are those most frequently in use at the time ofdevelopment of this International Standard.