教学课程资源库 更多>>

关键词： 动物性食品   抗生素残留   微生物学日允许摄入量   安全性评价   肠道菌群  

摘要： 国内外对市售食品的很多调研结果显示其抗生素残留情况不容忽视。由于通过食品可能造成长期低剂量接触抗生素,其对人体肠道菌群的潜在威胁已受到广泛关注。本文讨论了动物性食品中抗生素残留的主要原因,对人体肠道菌群的不良影响以及部分国际权威组织在对其进行安全性评价时采取的微生物学ADI的概念和步骤。

标准号: NF V08-105-2010

摘要： Le présent document décrit les principes de base de l'impédancemétrie utilisée pour la recherche et le dénombrement des micro-organismes dans les produits alimentaires par mesurage direct ou indirect de l'impédance.

关键词： 实验动物科学   比较医学   上海   动物实验技术   实验动物医学   动物生物学   学术刊物   科技领域  

摘要： 本刊系实验动物科技领域的专业性学术刊物，兼顾普及与提高，刊登实验动物和比较医学领域的研究论文，内容主要包括人类疾病动物模型、动物实验技术、动物生物学、实验动物医学、实验动物技术与管理和其他文章（文献综述、经验交流、检测报告、病例报告、简报、动态与书评等），

标准号: NF V08-010-5-2010

关键词： Taurine牛   基因组   基因序列   重复序列   动物进化  

摘要： 为了理解反刍动物的生物学和进化论,牛的基因组图被测定出有大约7倍区域(Genome sevenfold coverage)。整个序列含有最低限度22000个基因,有一套核心基因14345个,是7个哺乳动物种共享拥有的源祖同源基因或直系同源基因(Ortholog),其中有1217个基因在非真哺乳动物亚纲(有袋目动物或单孔目动物)基因组图中不存在或没被检测到。牛染色体特有的进化演变区的片断复制的密度较高,重复元素丰富,并且这种种类特有的基因变异与产乳和免疫反应有关。表达代谢的基因一般是高度保守的,但是人类跟它们同源的5个参与代谢的源祖同源基因已丢失或广泛地发生了漂移。牛的基因组图谱就这样为理解哺乳动物进化和加速家畜泌乳和产肉的遗传改进提供了一种资源。

关键词： RABBITS   NONFICTION  

摘要： The article reviews the book "Harkness and Wagner's Biology and Medicine of Rabbits and Rodents," 5th edition, by John E. Harkness, Patricia V. Turner, Susan Vande Woude and Colette L. Wheler.

关键词： Baculovirus   High throughput   Transient expression   HEK293 cells  

摘要： The production of proteins in sufficient quantity and of appropriate quality is an essential pre-requisite for structural studies. Escherichia coli remains the dominant expression system in structural biology with nearly 90% of the structures in the Protein Data Bank (PDB) derived from proteins produced in this bacterial host. However, many mammalian and eukaryotic viral proteins require post-translation modification for proper folding and/or are part of large multimeric complexes. Therefore expression in higher eukaryotic cell lines from both invertebrate and vertebrate is required to produce these proteins. Although these systems are generally more time-consuming and expensive to use than bacteria, there have been improvements in technology that have streamlined the processes involved. For example, the use of multi-host vectors, i.e., containing promoters for not only E. coli but also mammalian and baculovirus expression in insect cells, enables target genes to be evaluated in both bacterial and higher eukaryotic hosts from a single vector. Culturing cells in micro-plate format allows screening of large numbers of vectors in parallel and is amenable to automation. The development of large-scale transient expression in mammalian cells offers a way of rapidly producing proteins with relatively high throughput. Strategies for selenomethionine-labelling (important for obtaining phase information in crystallography) and controlling glycosylation (important for reducing the chemical heterogeneity of glycoproteins) have also been reported for higher eukaryotic cell expression systems. (C) 2010 Elsevier Inc. All rights reserved.

关键词： phenotype   fertilization   marine ecosystem   parental care   reproductive biology   life-history trait   family conflict   offspring evolution   Phenotype   Marine organisms   Family Conflict   life history   Parental behavior   descendant   Marine ecosystems   Conflict of Interest   Invertebrates, Marine   Life History Traits   Eggs  

摘要： All organisms face two fundamental trade-offs in the allocation of energetic resources: one between many small versus a few large offspring, and the second between present and future reproduction. Nowhere are these trade-offs more apparent than in the vast range of variation in the sizes of eggs and offspring exhibited among species of marine invertebrates. It has become increasingly clear that, in many taxa of marine organisms, there is also substantial intraspecific variation in the size of eggs and hatchings. This variation has largely been attributed to adaptive maternal effects. In theory, however, the inevitable conflicts of interest that arise in families of sexually reproducing organisms over the optimal distribution of parental resources among siblings could also account for much of this variation in egg and offspring size. Here, we explore the potential impacts of family conflict on offspring traits by comparing the life histories of two exemplar species of marine organisms, the polychaete Boccardia proboscidea and the gastropod Solenosteira macrospira, emphasizing how differences in modes of fertilization and parental care might influence the phenotype and, consequently, the fitness of offspring.

关键词： WILD BIRD POPULATION   FEMALE SOAY SHEEP   LIFE-HISTORY CONTINUUM   SEX-BIASED DISPERSAL   TWINS REDUCE FITNESS   TIT PARUS-MAJOR   PHENOTYPIC   PLASTICITY   NATURAL-POPULATIONS   CLIMATE-CHANGE   GREAT TIT   natural population   field focus   ecology   life history   Parus major  

摘要： Many important questions in ecology and evolutionary biology can only be answered with data that extend over several decades and answering a substantial proportion of questions requires records of the life histories of recognisable individuals. We identify six advantages that long-term, individual based studies afford in ecology and evolution: (i) analysis of age structure;(ii) linkage between life history stages;(iii) quantification of social structure;(iv) derivation of lifetime fitness measures;(v) replication of estimates of selection;(vi) linkage between generations, and we review their impact on studies in six key areas of evolution and ecology. Our review emphasises the unusual opportunities and productivity of long-term, individual-based studies and documents the important role that they play in research on ecology and evolutionary biology as well as the difficulties they face.