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51.
Ramos Silva JC Marvulo MF Dias RA Ferreira F Amaku M Adania CH Ferreira Neto JS 《Preventive veterinary medicine》2007,78(3-4):286-295
From September 1995 to February 2001, blood samples were collected from 865 neotropical felids belonging to 8 different species. These animals were housed in 86 institutions located in 78 cities of 20 Brazilian states. Our goal was to identify the risk factors associated with sero-positivity to Toxoplasma gondii in captive neotropical felids from Brazil. All serum samples were tested by the modified agglutination test (MAT), using formalin-fixed whole tachyzoites and mercaptoethanol. For each animal an individual questionnaire was filled with questions about tattoo number, felid species, age, sex, origin, number of animals in the group, introduction of new animals in the group, time in the institution, eating meat previously frozen for a period <7 days in the last 6 months, eating meat of run-over or euthanized animals in the last 6 months, predation of rodents or birds in the last 6 months and presence of domestic cats near the enclosures in the last 6 months. The total sero-prevalence was 55% (95% CI: 52%, 57%). We estimated a prevalence of 46% (95% CI: 40%, 54%) for jaguarundi (Puma yagouaroundi); 58% (95% CI: 53%, 63%) for ocelot (Leopardus pardalis); 50% (95% CI: 45%, 56%) for oncilla (L. tigrinus); 54% (95% CI: 46%, 62%) for margay (L. wiedii); 12% (95% CI: 4%, 31%) for Pampas-cat (L. colocolo); 83% (95% CI: 65%, 93%) for Geoffroy's-cat (L. geoffroyi); 64% (95% CI: 50%, 68%) for jaguar (Panthera onca) and 48% (95% CI: 42%, 54%) for puma (Puma concolor). Multiple logistic regression was used to evaluate the association between the variables in the questionnaire and sero-positivity to T. gondii. We concluded that the independent risk factors for toxoplasmosis were: age >3 years (OR = 4.75 [2.75; 8.2]), eating meat previously frozen for a period <7 days (OR = 2.23 [1.24; 4.01]), and consumption of animals that were run-over or euthanized (OR = 1.64; [1.14; 2.37]). 相似文献
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本文运用酶解去壁低渗法,对贵州省桑属植物种质资源材料27份进行了染色体倍数性研究。结果如下:1.二倍体(2n=2x=28)5个。2.三倍体(2n=3x=42)1个。3.六倍体(2n=6x=84)21个。丰富了桑属植物染色体研究内容,为桑树遗传育种提供了理论和实践依据。 相似文献
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Liu Chongde Wang Xiaoming Gu Lan 《保鲜与加工》1992,(6):10-17
A optimal design with whole structure parameters and its program are carried out. A reasonable model is established. Using the method a optimal design with whole structure parameters by original parameters of American P&H2300xp excavator was calculated. The size,carried out by the method,approximates to the size of P&H2300xp excavator very well. 相似文献
57.
Gu Qiankun Tang Yike Yu Youju Xie Zhijiang Liang Xichang 《保鲜与加工》1997,(6):96-102
The dynamic characteristic of active isolation atuator on flexible foundations was studied under the installation of parallel structure and foundation cancellation.The influencing relationships between active isolation force of the different installation ways and passive isolation system and flexible foundation were analyzed and compared.Scientific basis for selecting installation ways of active isolator is provided in this paper. 相似文献
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ln this paper,we firstly in vestigated the un icity properties of meromorphic functions with three common values,extended the results of H. Ueda,Yi Hongxun.Moreover,wealso improved the results of K,Shibazaki,Yi Hongxun and C,C,Yang,Hua xinhou and some others 相似文献
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In this paper,the electrical field distribution along the polluted cylindrical insu-lator before a nd after the local a re appea rs is calculated with the optim lzed pa rtially cha rge simula-tinn method and measured with the pockels device. Based on the calculating and measuring results,the in fluen ce of the electric field distri bu tion on the propagation of local a re in the flashover ofcyIlndrical insufator under various conditions is analyzed systematieally. 相似文献