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关键词： 海水   鱼类   甲壳动物   生物学   鱼虱  

摘要： 对海水鱼类寄生甲壳动物生活史、环境因子对鱼虱发育的影响、鱼虱的种间进货关系、形态结构与功能、生殖器官与繁殖等生物学问题研究现状进行描述，并对存在问题及今后的研究方向进行探讨。

摘要： In situ egg production of the egg-carrying calanoid copepod Pseudodiaptomus marinus was investigated in Fukuyama Harbor, a eutrophic inlet of the Inland Sea of Japan, at 3- to 5-d intervals for a year. This species reproduced throughout the year, and the adults showed a large abundance peak in June/July and a small peak in September/October. Females usually outnumbered males, comprising 61.4% of the annual mean. The composition of ovigerous females varied from 7.9 to 100%, with an annual mean of 55.7%. Adult prosome length was consistently large throughout winter and spring, and decreased with increasing temperature in summer and fall. Egg diameter varied from 98 to 121 mu m, and was negatively correlated to temperature. The seasonal variation in clutch size (range: 15.1 to 38.2 eggs) was bicyclical, with peaks in May and December. The egg production rate of breeding females was low in January to March (mean: 2.3 eggs female(-1) d(-1)), while it was constantly high from mid-May to early October (mean: 12.1 eggs female(-1) d(-1)). The specific egg production rate for the breeding females was highly correlated to temperature;it increased linearly from 0.03 d(-1) at 9 degrees C to 0.27 d(-1) at 26 degrees C. Compared to other co-occurring copepods, the reproductive rate of P. marinus was lowest, which is one of the reasons why this species never dominates in this inlet.

关键词： 农产品   分析   饲料   细菌纲   数据分析   定义(术语)   检测   食品检验   食品   溶血   水平的   研究方法   单核细胞增生李斯特氏菌   介质   方法   分析法   微生物分析   微生物学   微生物   精密度   抽样方法   试验媒体   验证  

标准号: BS EN ISO 11290-1-1996+A1-2004

摘要： This part of ISO 11290 specifies a horizontal method for the detection of Listeria *** to the limitations discussed in the introduction, this part of ISO 11290 is applicable to products intended for human consumption or animal feeding.

关键词： 农产品   分析   饲料   细菌   数据分析   定义   检测   食品检验   食品   溶血作业   水平的   研究方法   单核细胞增生性利斯特氏菌   介质   方法   分析方法   微生物分析   微生物学   微生物   精密度   抽样方法   试验培养基   验证  

标准号: BS EN ISO 11290-1-1996

摘要： This part of ISO 11290 specifies a horizontal method for the detection of Listeria monocytogenes. Subject to the limitations discussed in the introduction, this part of ISO 11290 is applicable to products in-tended for human consumption or animal feeding.

标准号: NF V08-052-1997

摘要： Le présent document spécifie une méthode de routine pour la recherche des Salmonella dans les produits destinés à l'alimentation humaine ou à l'alimentation animale. Le présent document simplifie la méthode de référence NF EN ISO 6579 (voir article 13), essentiellement par l'isolement sur une seule gélose, laissée au choix de l'utilisateur.

关键词： computers   mathematical models   prediction   pastures   feed intake   productivity   nutritive value   grazing systems   computer software   models Australia sheep   cattle  

摘要： This paper specifies the animal biology module of a model for simulating grazing systems for ruminants on pasture. The program predicts the intake of energy and protein, allowing for selective grazing and substitution by supplementary feeds, and estimates the use of the diet for maintenance and production, according to current feeding standards. Conception and death rates are predicted from the maturity and condition of the animals. The model is designed to be of general application to any type of sheep or cattle on any pasture. GrazFeed is a discrete package that uses the same procedures for predicting feed intake and productivity within a tactical decision support system. This is designed to help graziers to assess the feeding value of specified pastures and the need for the supplementary feeding of different classes of grazing animals. (C) 1997 Published by Elsevier Science Ltd.

关键词： homology   segmentation   tagmosis   Crustacea   Hexapoda   Myriapoda  

摘要： Phylogenetic, morphological, and developmental data concerning the Arthropoda are reviewed and discussed with the aim of reconstructing the ancestral body plan of the mandibulate arthropods (Myriapoda, Hexapoda, Crustacea). Comparative morphology as well as embryology of malacostracans and hexapods (cell-lineages, patterns of mitotic domains, patterns of en-stripe formation, expression zones of pair-rule, homeotic, and gap-like genes) suggest that (a) the basic boundary subdividing the mandibulate body into the primary embryonic regions, anterior protocephalon and posterior protocorm, runs anteriorly to parasegment PS1 (=within the mandibular segment);(b) protocephalon (pregnathal region) probably is not a unitary body region;(c) maxillary segments are closely related to the postgnathal trunk segments;(d) the ''typical'' mandibulate head (pregnathal-mandibular-maxillaly) is not developed in all Mandibulata and has evolved several times in parallel;and (e) postcephalic tagmosis is much less conserved, and probably more recent, than tagmosis of more anterior areas. The arachnomorphan anterior tagma, the prosoma, is compared with the hypothesized ancestral mandibulate head.

关键词： 正常值   出血   统计学方法   血清蛋白   实验动物   解剖   聚丙烯酰胺凝胶电泳   红鲫   生物学特性   性状  

摘要： 本研究测量了40尾红鲫共23项解剖性状，并用统计学方法进行了统计分析，得出能代表正常值的平均数。此外，用聚丙烯酸胺凝胶电泳方法分离出血清蛋白7条带。

关键词： accessory olfactory bulb   olfaction   olfactory receptor   pheromone   vomeronasal  

摘要： In mammals, olfactory sensory perception is mediated by two anatomically and functionally distinct sensory organs: the main olfactory epithelium (MOE) and the vomeronasal organ (VNO). Pheromones activate the VNO and elicit a characteristic array of innate reproductive and social behaviors, along with dramatic neuroendocrine responses. Recent approaches have provided new insights into the molecular biology of sensory transduction in the vomeronasal organ. Differential screening of cDNA libraries constructed from single sensory neurons from the rat VNO has led to the isolation of a family of genes which are likely to encode mammalian pheromone receptors. The isolation of these receptors from the vomeronasal might permit the analysis of the molecular events which translate the bindings of pheromones into innate stereotypic behaviors and help to elucidate the logic of pheromone perception in mammals.

关键词： 斑马鱼   发育生物学   脊椎动物模型  

摘要： 从八十年代初开始的、通过突变体分离早期胚胎发育基因的研究，揭示了无脊椎动物果蝇形态发生的分子机制，成为1995年诺贝尔生理或医学奖的主要内容，同时也标着发育生物学已经成为生物学的带头学科。该成果的取得得益于果蝇具备发育生物学研究模型的特点，即可同时进行胚胎学和发育遗传学研究。在脊动物发育生物学研究方面，由于缺少适当的研究模型，有关早期胚胎发育基因表达调鬼斧神工的研究始终未获突破性进展。包括小鼠、鸡、爪蟾等在一些脊椎动物都只适用于胚胎学或者遗传学某一学科的研究，均不是理想的发育生物学研究模型。一种小型的鲤科鱼－斑马鱼，逐渐成为发育生物学研究的最佳脊椎运动模型。它光周期产卵、卵大，胚胎在体外发育，胚胎发育速度快，早期胚胎完全透明，这些特点使它成为很好的脊椎动物胚胎学研究模型；同时，它个体小，产卵量大，产卵周期短，单倍体、雌核发育二倍体的制作和突变体的获得均较容易，精子可以冷冻保存，所有这些特点又使斑马鱼非常适合于发育遗传学研究。本文将详细论述斑马鱼作为脊椎动物发育生物学研究模型的特点，以及作为模型动物正在进行的有关工作。