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关键词： 福州内河   浮游动物   群落生态   水质评价  

摘要： 对福州内河进行为期一周年的浮游动物群落生态研究，以期利用浮游动物群落结构变化，结合理化指标对福州内河进行水质综合评价，为福州内河合理、有效的治理提供基础资料。2000年9月至2001年8月，在内河的主要河道设置12个采样点，对浮游动物进行定性和定量的采集，同步进行温度、pH值和电导率三项物理指标以及氨氮、总磷、总氮、高锰酸盐指数和溶解氧五项化学指标的测定。 对浮游动物进行种类鉴定，确定了常见种和优势种，研究了浮游动物群落数量和生物量的周年变动以及温度、pH值对浮游动物群落的影响。通过理化指标的测定、计算环境质量综合指数(PI)及化学评价指数(Pb／n)对内河水质进行评价。同时利用指示生物法、三种多样性指数：Simpson多样性指数、Shannon-Weaner多样性指数、Margalef多样性指数及种类污染值(SpeciesPollution Value，SPV)和群落污染值(Community Pollution Value，CPV)，分别对内河进行水质生物学评价。最后，结合三项多样性指数和五项化学指标，运用主成分分析和聚类分析评价内河的水质，并对内河进行营养型和黑臭率评价。 综合各种评价方法，测定内河的水质大多处于甲型中污和乙型中污之间，部分为多污，主要为富营养型。实验结果与十年前内河水质调查的结果进行比较，得出福州内河水质没有明显的转变，但黑臭率有所改善，最后分析了内河污染的成因，并提出治理的意见和建议。

标准号: NF V08-002/A1-2001

关键词： 苔藓动物   后生动物   起源   系统发生   形态学   分子生物学   化石  

摘要： 苔藓动物是后生动物中的一个重要类群。然而 ,和其它主要后生动物类群相比 ,长期以来对它的系统学研究却相对滞后。其起源、系统发生地位以及与其它后生动物门类之间、其内部各高级分类群间的谱系发生关系一直存在争议。一般认为它是介于原口动物和后口动物之间的过渡类群。但是 ,近年来的分子系统学研究已经证实了它的原口动物归属。古生物学资料表明 ,虽然苔藓动物的大多数类群在奥陶纪已经分化出来 ,但它在寒武纪却缺乏任何化石记录。另外 ,苔藓动物起源的时间和方式、其内部各类群间的系统发生关系特别是现生类群和化石类群之间的关系等诸多问题的解决 ,还有待于大量的形态学和不同的分子数据的进一步积累 。

关键词： 人工角膜   组织相容性   胶原蛋白   葡萄糖氨基聚糖   氩等离子体  

摘要： 目的　探讨 3种人工角膜支架材料经氩等离子体 (Argonplasma)处理后植入兔角膜对角膜组织的生物学反应的影响。方法　选用 3种支架材料 :由 80 %的聚丙烯和 2 0 %聚丁烯化合而成的多孔材料 ;Polyester多孔材料 ;Ex pendedpolytetrafluoroethylene。处理组材料经Argonplasma处理。将盘状支架材料植入兔角膜囊袋内。 结果　材料经处理后角膜水肿较未处理明显减轻 ,8周后 3种材料中角膜水肿均消失。材料 1,2植入时新生血管出现延迟 ,范围小 ,炎细胞浸润明显减少。术后 6周纤维细胞迁徙入材料内。当材料植入角膜后角化蛋白 (KS)含量降低 ,Dermatan(DS)含量增高 ,并有大分子葡萄糖聚糖 (GAG)出现。结论　Argon plasma处理可明显减轻兔角膜炎症反应 ,增加材料的组织相容性。

关键词： Animals   Behavior, Animal   Biology/education   Dinosaurs   Fantasy   Gait   Great Britain   Great Britain   Mammals/physiology   Natural History/education   Paleontology/education   Research   Television   United States  

摘要： Norwich, U.K.--After dinosaurs, mammals took center stage: in real life andon television. The same production team that made giant reptiles stomp and roar across our screensin Walking with Dinosaurs is continuing where the series left off, 65 million years ago. Like itspredecessor, Walking with Beasts--a six-part series that began in the U.K. this month and will airon a single night (9 December) in the United States--blends expert knowledge, computer animation,and mechanized models to present extinct mammals feeding, fighting, and fleeing in a "wildlifedocumentary" format. This time around, the BBC programmakers faced new challenges, including asubject less familiar to the public and dominated by twitchy, hairy creatures that are harder toanimate than dinosaurs. And the makers have taken the bold step of conjuring our own distantancestors, inferring behavior from modem apes. "It was a very daring decision," says paleontologistMichael Benton of the University of Bristol, U.K. Benton is a vocal supporter of a production thatinevitably attracts criticism from experts, just as Dinosaurs did 2 years ago for its blending offact and inspired guesswork into appealing scenarios (Science, 7 April 2000, p. 29). Because of thesuccess of Dinosaurs, the team stuck to the same recipe for Beasts, but this time around theprogrammakers provided even more background material using Web sites and interactive TV. "It's alllaid out bare for anyone to look at" says series producer Jasper James. "We hide nothing."

关键词： molecular biology   nematodes   trematodes   vaccines   recombinant proteins   genomics  

摘要： Rapid developments in molecular biology have had an enormous impact on the prospects for the development of vaccines to control the major nematode and trematode infestations of livestock. Vaccine candidates are purified using conventional protein chemistry techniques but the limitations imposed by the scarcity of parasite material provide an insurmountable barrier for commercial vaccine production by this means. The ability to purify mRNA from different parasite life-cycle stages and to prepare cDNA expression libraries from it has proven central to the identification of immunogenic parasite proteins, Potentially, protective parasite antigens can now be produced in recombinant form in a variety of vectors and this represents a key breakthrough on the road to commercial vaccine production. The contribution of molecular biology to this process is discussed using several examples, particularly in vaccine development against the pathogenic abomasal nematode of sheep and goats, Haemonchus contortus, and the liver fluke of sheep and cattle, Fasciola hepatica. The difficulties of producing recombinant proteins in the correct form, with appropriate post-translational modification and conformation, are discussed as well as emerging means of antigen delivery including DNA vaccination. The opportunities offered by genome and expressed sequence tag analyses programmes for antigen targeting are discussed in association with developing microarray and proteomics technologies which offer the prospect of large scale, rapid antigen screening and identification. Crown Copyright (C) 2001 Published by Elsevier Science B.V. All rights reserved.

关键词： Animals   Animals, Zoo/anatomy & histology   Animals, Zoo/physiology   Conservation of Natural Resources   Cryopreservation   Cryopreservation   Elephants/anatomy & histology   Elephants/physiology   Female   Genitalia, Female/ultrasonography   Insemination, Artificial/veterinary   Male   Pregnancy   Semen Preservation   Semen Preservation   Ultrasonography/veterinary  

摘要： Berlin--Few people in the world are as intimately familiar with the elephantcervix as Thomas Hildebrandt. That particular knowledge may not make the 37-year-old veterinarian ahit at a cocktail party, but it has won him admirers in zoos around the world. Hildebrandt and hiscolleagues at the Institute for Zoo Biology and Wildlife Research (IZW) in Berlin have pioneered aninnovative approach--artificial insemination (Al) technology aided by ultrasound--to impregnate halfa dozen elephants, raising hope that zoos will be able to maintain their populations of thesehard-to-breed creatures. Hildebrandt's ultrasound techniques "have revolutionized our ability toassess elephant reproductive health," says Janine Brown of the Smithsonian National Zoological Parkin Washington, D.C., where an elephant named Shanthi is expected to give birth next month--thanks tothe "Berlin Boys" as the IZW team is known. These days, the team's prowess at making babies is inhigh demand. Scores of zoo elephants are nearing the end of their life-spans, while recent laws havemade it nearly impossible to import endangered species from the wild. Without Al, say severalexperts, zoo elephants could all but disappear within 2 decades. Other rare animals are also fallingfor the charms of these high-tech love doctors. Hildebrandt and colleagues Frank G6ritz and RobertHermes have used their ultrasound instruments to probe the internal organs of more than 200 species,including giant pandas, Komodo dragons, endangered European brown hares, and even invertebrates:Hildebrandt has used his technique to sex an octopus at Washington's Na- tional Zoo. "He'llultrasound just about anything that lives or crawls," says Richard Montali, head of the NationalZoo's pathology department.

标准号: NF V08-033-2001

摘要： La présente Norme internationale spécifie une méthode de dénombrement des micro-organismes psychrotrophes par le biais d'une technique de comptage des colonies à 6,5 oC. Cette méthode est applicable aux produits destinés à la consommation humaine ou aux aliments destinés aux animaux.

关键词： cephalopods   chromatophores   pigments   body patterning   motor system   camouflage   signalling   vision  

摘要： The chromatophores of cephalopods differ Fundamentally from those of other animals: they are neuromuscular organs rather than cells and are not controlled hormonally. They constitute a unique motor system that operates upon the environment without applying any force to it. Each chromatophore organ comprises an elastic sacculus containing pigment, to which is attached a set of obliquely striated radial muscles, each with its nerves and glia. When excited the muscles contract, expanding the chromatophore;when they relax, energy stored in the elastic sacculus retracts it. The physiology and pharmacology of the chromatophore nerves and muscles of loliginid squids are discussed in detail. Attention is drawn to the multiple innervation of dorsal mantle chromatophores, of crucial importance in pattern generation. The size and density of the chromatophores varies according to habit and lifestyle. Differently coloured chromatophores are distributed precisely with respect to each other, and to reflecting structures beneath them. Some of the rules for establishing this exact arrangement ha-ve been elucidated by ontogenetic studies. The chromatophores are not innervated uniformly: specific nerve fibres innervate groups of chromatophores within the fixed, morphological array, producing 'physiological units' expressed as visible 'chromatomotor fields'. The chromatophores are controlled by a set of lobes in the brain organized hierarchic ally. At the highest level, the optic lobes, acting largely on visual information, select specific motor programmes (i.e. body patterns);at the lowest level, motoneurons in the chromatophore lobes execute the programmes, their activity or inactivity producing the patterning seen in the skin. In Octopus vulgaris there are over half a million neurons in the chromatophore lobes, and receptors for all the classical neurotransmitters are present, different transmitters being used to activate (or inhibit) the different colour classes of chromatophore mo