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Both monoclonal and polyclonal antisera were produced against Ceratomyxa shasta. Ascites containing trophozoites of the parasite was collected from infected fish and used as antigen for immunization of mice. The resulting monoclonal antibodies reacted specifically with trophozoite and sporoblast stages but did not react with C. shasta spores by either indirect fluorescent antibody techniques or in Western blots. This indicates that some C. shasta antigens are specific to certain life stages of the parasite. Polyclonal antiserum was produced in a rabbit by injecting a spore protein electro-eluted from an SDS-polyacrylamide gel. This antiserum reacted with both trophozoites and spores by indirect fluorescent antibody techniques and in Western blots. All antisera were tested for cross-reactivity to trout white blood cells, a contaminant of the ascites, and to other myxosporea. Two monoclonal antibodies reacted with white blood cells and myxosporea of the genera Sphaerospora and Myxobilatus. One hybridoma produced antibodies of high specificity for C. shasta pre-spore stages. This is the first report of a monoclonal antibody produced against a myxosporean parasite.  相似文献   
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Aerial photographic sample censuses of the flamingoes and pelicans on Lakes Nakuru and Hannington were carried out on four occasions between October 1968 and March 1969. On Lake Nakuru the estimated numbers of flamingoes varied between 172 000 and 401 000, and the pelicans between 6800 and 27 900. There were no pelicans on Lake Hannington, but the number of flamingoes varied between 507 000 and 634 000. It was not possible to distinguish between greater and lesser flamingoes, or between white and pink-backed pelicans on the aerial photographs. On 28–30 March 1969 a census was carried out on twenty-four lakes, between Lake Hannington in the north and the Singida lakes in the south. The total number of flamingoes seen was just over one million, with 22 000 pelicans. About 100 000 lesser flamingo nests were counted from aerial photographs taken over Lake Natron in November 1969.  相似文献   
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高黎贡山兰花的多样性   总被引:4,自引:0,他引:4  
对高黎贡山兰科植物的生物地理学和多样性进行了研究。1.兰科是高黎贡山种子植物中最大的科,包括75属265种。2.高黎贡山兰花起源于新、旧世界的热带和温带, 热带属占60%(45属),温带属占38.67%(29属),包括2个云南特有属。但是,高黎贡山兰科植物与地中海地区和中亚地区的联系十分微弱。3.高黎贡山的兰花以地生兰为主。这里,57.33%(43属)为地生兰,而附生兰和腐生兰仅分别为31属和3属。4.兰花物种的分布区式样表明高黎贡山兰花以温带兰为主 温带兰占总种数的69.43%(184种),包括东亚成分即滇西高黎贡山-东喜马拉雅分布的种和中国西南部特有种,它们是高黎贡山兰花区系的核心。5.高黎贡山兰科的特有现象在于1)具有云南二个特有属蜂腰兰Bulleyia和反唇兰Smithorchis;2)有高黎贡山特有种21个,如泸水兜兰Paphiopedilum markianum,贡山风兰Cymbidium gongshanense,贡山贝母兰Coelogyne gongshanense,热带附生兰——万带兰亚科在高黎贡山没有形成特有种;3)高黎贡山北段的特有种比南段丰富贡山有14种,腾冲仅有4种; 海拔1800~2100 m的梯度带特有种最多(13种);4)高黎贡山有云南特有种10种,其中小花槽舌兰Holcoglossum junceum是一个热带种,因为板块位移而来到了亚热带地域;5)高黎贡山的兰科植物中有19.25%(51种)是中国特有种,它们出现在高黎贡山,分布在云南其他地区和西南的一些省区。高黎贡山特有种,分布到高黎贡山的云南特有种和分布到高黎贡山的中国特有种一共为82种,占高黎贡山兰科总种数的30.91%, 兰科在高黎贡山是一个特有化程度很高的类群。  相似文献   
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