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关键词： 农产品   乳制品分析   乳制品   稀释   稀释法   食品检验   食品   微生物分析   微生物学   牛奶   奶制品   试样制备   悬浮液   测试  

标准号: BS EN ISO 6887-5-2010

摘要： WARNING — The use of this International Standard may involve hazardous materials, operations, andequipment. It is the responsibility of the user to establish appropriate health and safety practices andto determine the applicability of regulatory limitations prior to *** part of ISO 6887 specifies rules for the preparation of samples of milk and milk products and theirsuspension for microbiological examination when the samples require a different preparation from the generalmethods specified in ISO 6887-1. ISO 6887-1 defines the general rules for the preparation of the initialsuspension and decimal dilutions for microbiological *** part of ISO 6887 excludes preparation of samples for both enumeration and detection test methodswhere preparation details are specified in the relevant International *** part of ISO 6887 is applicable to:a) milk and liquid milk products;b) dried milk products;c) cheese;d) casein and caseinates;e) butter;f) ice-cream;g) custard, desserts and sweet cream;h) fermented milk and sour cream;i) milk-based infant foods.

摘要： The mammalian middle ear represents one of the most fundamental morphological features that define this class of vertebrates. Its skeletal pattern differs conspicuously from those of other amniotes and has attracted the attention of comparative zoologists for about 200 years. To reconcile this morphological inconsistency, early comparative morphologists suggested that the mammalian middle ear was derived from elements of the jaw joint of nonmammalian amniotes. Fossils of mammalian ancestors also implied a transition in skeletal morphology that resulted in the mammalian state. During the latter half of the 20th century, developmental mechanisms controlling the formation of the jaw skeleton became the subject of studies in developmental biology and molecular genetics. Mammalian middle ear evolution can now be interpreted as a series of changes in the developmental program of the pharyngeal arches. In this review, we summarize the history of middle ear research, highlight some of the remaining problems, and suggest possible future directions. We propose that to understand mammalian middle ear evolution, it is essential to identify the critical developmental events underlying the particular mammalian anatomy and to describe the evolutionary sequence of changes in developmental and molecular terms. We also discuss the degree of consistency between the developmental explanation of the mammalian middle ear based on molecular biology and morphological changes in the fossil record. J. Exp. Zool. (Mol. Dev. Evol.) 3148:417-433, 2010. (C) 2010 Wiley-Liss, Inc.

关键词： Telomere   Telomerase   Senescence   Metazoa   Vertebrate   Invertebrate  

摘要： In this review we present critical overview of some of the available literature on the fundamental biology of telomeres and telomerase in Metazoan. With the exception of Nematodes and Arthropods, the (TTAGGG)(n) sequence is conserved in most Metazoa. Available data show that telomerase-based end maintenance is a very ancient mechanism in unicellular and multicellular organisms. In invertebrates, fish, amphibian, and reptiles persistent telomerase activity in somatic tissues might allow the maintenance of the extensive regenerative potentials of these species. Telomerase repression among birds and many mammals suggests that, as humans, they may use replicative aging as a tumor protection mechanism. (C) 2010 Federation of European Biochemical Societies. Published by Elsevier B. V. All rights reserved.

关键词： Wildlife DNA   Laboratory   Forensic identification   Validation   Illegal trade  

摘要： Wildlife DNA forensics is receiving increasing coverage in the popular press and has begun to appear in the scientific literature in relation to several different fields. Recognized as an applied subject, it rests on top of very diverse scientific pillars ranging from biochemistry through to evolutionary genetics, all embedded within the context of modern forensic science. This breadth of scope, combined with typically limited resources, has often left wildlife DNA forensics hanging precariously between human DNA forensics and academics keen to seek novel applications for biological research. How best to bridge this gap is a matter for regular debate among the relatively few full-time practitioners in the field. The da wiecisions involved in establishing forensic genetic services to investigate wildlife crime can be complex, particularly where crimes involve de range of species and evidential questions. This paper examines some of the issues relevant to setting up a wildlife DNA forensics laboratory based on experiences of working in this area over the past 7 years. It includes a discussion of various models for operating individual laboratories as well as options for organizing forensic testing at higher national and international levels.

关键词： integument   hair follicle   keratins   growth factors   melanocytes  

摘要： Hair 'fine' fibre is an important commercial product of farmed and certain wild animal species. The fibre is produced in follicles embedded in skin. These have properties in common with other tissues of the integument and have importance in determining yield and quality of fibre. Means of understanding and improving these characteristics are informed by knowledge of integumental and follicle biology This paper reviews contemporary information that identifies the major fibre-producing species and their production characteristic. It surveys knowledge describing fundamental biology of the integument and considers information derived for the hair follicle from studies on a number of species including genetically modified mice. It identifies the composition of the follicle and describes components and interrelationships between epidermal hair-fibre producing epidermis and fibroblast and connective tissue-containing dermis. The structure of different primary and secondary follicle types, and associated structures, are described. Focus is given to the alterations in anatomy and in behaviour from active to inactive state, which occurs during the hair follicle cycle. Information is provided on the anatomical substructures (hair medulla, cortex, cuticles and supporting sheaths and dermal papilla), cellular and extracellular composition, and adhesion and chemical signalling systems, which regulate development from the early embryo to post-natal state and subsequent cycling. Such signalling involves the dermis and its specialist fibroblasts, which secrete signalling molecules, which along with those from local epidermis and systemic sources, largely determine structure and function of epidermal cells. Such chemical signalling typically includes endocrine-, paracrine-, autocrine- and juxtacrine-acting molecules and interactions with their receptors located on cell membranes or intracellularly with transduction of message mediated by transcription factors at gene level. Important

关键词： ecotypes   Animals   Biological   ideal model   ANIMAL GROUPS   Annelida   Model Studies   Freshwater environments  

摘要： Annelids are among the most ecologically diverse animal groups, colonizing every habitat type around the world, especially marine and freshwater environments. This high diversity, coupled with a simple body plan, makes them an ideal model for studying fundamental biological problems. These organisms have been extensively treated in the past in many basic studies, and the literature on polychaete development remains among the most detailed and accurate descriptive work. However, in certain biological fields they are a relatively unexplored animal group.

关键词： ANOXEMIA   BIOCOMPATIBILITY   ADJUSTMENT (Psychology)   ADAPTATION (Biology)   DROSOPHILA   TRANSCRIPTION factors   ANIMAL psychology  

摘要： Many invertebrates and ectothermic vertebrates successfully cope with a fluctuating supply of ambient oxygen- and consequently, a highly variable tissue oxygenation-through increasing their antioxidant barriers. During chronic deprivation of oxygen, however, the hypometabolic defense mode of the fruit fly Drosophila, the hypoxia-induced behavioral hypothermia of the crayfish Pacifastacus leniusculus, and the production of ethanol during anoxia by the crucian carp Carassius carassius all indicate that these animals are also capable of utilizing a suite of genetic and physiological defenses to survive otherwise lethal reductions in tissue oxygenation. Normally, much of an organism's gene response to hypoxia is orchestrated via the hypoxia-inducible transcription factor HIF. Recent developments expand our view of HIF function even further by highlighting regulatory roles for HIF in the hypometabolism of insects, in the molting and the normoxic immune response of crustaceans, and in the control-via the downstream effector gene erythropoietin-of the hypoxic ventilatory response and pulmonary hypertension in mammals. These and related topics were collectively presented by the authors in a symposium of the 2008 ICA-CBP conference at Mara National Reserve, Kenya, Africa. This synthesis article communicates the essence of the symposium presentations to the wider community.

关键词： 首都医科大学   实验动物科学   实验动物学   基础医学院   医学生物学   主任   生命科学   科学研究  

摘要： 实验动物科学是现代生命乖斗学中新崛起的一门综合性、交叉性学科，是生命科学研究的支撑条件和重要组成部分，也是现代生命科学前沿领域中最为活跃的学科门类之一。近日，本刊记者就实验动物科学研究国内外最新进展以及对生命科学发展、进步的推动作用，采访了首都医科大学基础医学部实验动物系副主任陈振文教授。

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），

关键词： Giardia duodenalis   Novel assemblage   Population biology   Phoca vitulina vitulina   Phoca vitulina richardsi   Halichoerus grypus   Marine vertebrates  

摘要： Giardia duodenalis is an intestinal parasite of many vertebrates. The presence of G. duodenalis in the marine environment due to anthropogenic and wildlife activity is well documented, including the contributions from untreated sewage and storm water, agricultural run-off and droppings from terrestrial animals. Recently, studies have detected this protistan parasite in the faeces of marine vertebrates such as whales, dolphins, seals and shore birds. To explore the population biology of G. duodenalis in marine life, we determined the prevalence of G. duodenalis in two species of seal (Halichoerus grypus, Phoca vitulina vitulina and Phoca vitulina richardsi) from the east and west coasts of the USA, sequenced two loci from G. duodenalis-positive samples to assess molecular diversity and examined G. duodenalis distribution amongst these seals and other marine vertebrates along the east coast. We found a significant difference in the presence of G. duodenalis between east and west coast seal species. Only the zoonotic lineages of G. duodenalis, Assemblages A and B and a novel lineage, which we designated as Assemblage H, were identified in marine vertebrates. Assemblages A and B are broadly distributed geographically and show a lack of host specificity. Only grey seal (Halichoerus grypus) samples and one gull sample (Larus argentatus) from a northern location of Cape Cod, Massachusetts, USA, showed the presence of Assemblage H haplotypes;only one other study of harbour seals from the Puget Sound region of Washington, USA previously recorded the presence of an Assemblage H haplotype. Assemblage H sequences form a monophyletic clade that appears as divergent from the other seven Assemblages of G. duodenalis as these assemblages are from each other. The discovery of a previously uncharacterised lineage of G. duodenalis suggests that this parasite has more genetic diversity and perhaps a larger host range than previously believed. (C) 2010 Australian Society for Parasitolog