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11.
首先将非结构成分加以分类,对两个分支转向语句的交错重叠的四种情况建立了识别分析模型,并给出非结构化模式的识别和判别算法.然后利用分离、复制等方法,对四种非结构化模式加以结构化,得到相应的结构化模式 相似文献
12.
通过对移民安置区产业劳动力容量及安置容量研究,提出了移民安置区产业劳动力容量及安置容量的定义,计算方法及步骤,并对典型区进行实例分析,该研究成果对编制我国水利水电工程的移民安置规划,合理确定移民安置区各产业的安置容量,有一定的理论和实践意义。 相似文献
13.
海洋噬菌蛭弧菌对对虾病原菌及其他细菌的寄生作用 总被引:20,自引:0,他引:20
用宿主双层琼脂平板法,测定海洋噬菌蛭弧菌对25株对虾病原菌和大肠杆菌、枯草杆菌、绿脓杆菌及金黄色葡萄球菌的寄生作用,结果表明噬菌蛭弧菌菌株不同寄生的范围不同,但所有供试寄主细菌都能被某些蛭弧菌寄生,形成清晰的噬斑.用相差显微镜和电镜观察蛭弧菌的形态及噬菌过程 相似文献
14.
叶螨类害虫已成为我国蔬菜、果树和花卉的主要害虫。本文概述了叶螨对寄主植物的选择,叶螨危害寄主植物的机制研究和寄主植物对叶螨的生理抗性等方面的研究进展,进一步了解叶螨和植物的相互关系。 相似文献
15.
在调查厦门集美附近海域棱Lizacarinatus(CuvieretValenciennes)复殖类吸虫时,从其消化道检获2种复殖吸虫,即:易脆贫黄吸虫(PaucivitellosusfragilisCoil,ReidetKuntz,1965)和分节萨特吸虫(SaturniussegmentatusManter,1969).其中棱为易脆贫黄吸虫的宿主新记录;棱和台湾海峡为分节萨特吸虫的宿主和地理分布新记录.对分节萨特吸虫的观察结果表明:排泄囊为"Y"型,其主干延伸至第4个假分节的中部.有子宫受精部. 相似文献
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17.
《Journal of Natural History》2012,46(5):953-959
The order Misophrioida is recorded for the first time in Brazilian waters and the new species Archimisophria squamosa, with some important plesiomorphic features, is described. 相似文献
18.
《Journal of Natural History》2012,46(5):683-699
Two new species representing new genera of tantulocaridans are described from western Japan. Paradoryphallophora inusitata n.g., n.sp. is parasitic on deep-sea asellote isopods and belongs in the family Doryphallophoridae. It differs from the type genus Doryphallophora in the form of the abdomen and thoracopods of the adult male, and in the stylet and the pore pattern on the dorsal cephalic shield of the tantulus larvae. Hypertantulus siphonicola n.g., n.sp. infests shallow-water siphonostomatoid copepods and is assigned to the family Basipodellidae on the basis of the pattern of thoracic tergite separation of the male trunk sac. A developing sexual female is described, only the second known from the Tantulocarida. This is the first record of tantulocaridans on a representative of the copepod order Siphonostomatoida and the first case of presumed hyperparasitism recorded in the group. 相似文献
19.
Hiroshi Shima 《Journal of Natural History》2016,50(25-26):1649-1668
The Oriental genus Hygiella Mesnil is revised: three species are described as new, Hygiella angustifrons sp. nov., Hygiella luteipes sp. nov. and Hygiella proclinata sp. nov., and two known species are re-described, Hygiella nigripes Mesnil and Hygiella pygidialis Mesnil. A key to these five species is provided. The host of H. proclinata, Phyllium siccifolium (Linnaeus) (Phasmatodea: Phylliidae), is recorded for the first time as a host of the Tachinidae. The systematic position of Hygiella is discussed and the genus is placed in the tribe Acemyini (Exoristinae) based on the structure of the male terminalia. 相似文献
20.
《Journal of Natural History》2012,46(3):599-607
The sites of attachment of four larval watermite species were recorded from four corixid species in Lough Corrib, Ireland. Parasitic watermites exhibited preferences in respect of attachment sites on the corixid hosts and these patterns were consistent for all host species examined. Hydrachna cruenta utilized areas of the host which were in direct contact with the water, the distribution of larvae reflecting the general behaviour and microdistribution of the hosts. Hydrachna conjecta infected the ventral hemielytra with a significant asymmetrical distribution on the right hemielytron, resulting from the folding pattern of the hemielytra and the larval route of entry to the subhemielytral air space. Eylais species attached to the abdominal terga of the host, E. infundibulifera infecting the anterior two terga and E. discreta terga three and four. Cymatia bonsdorffi was not parasitized by E. infundibulifera and on this host the majority of E. discreta attached to the second abdominal tergite. Eylais species infecting small corixid hosts may avoid interference competition with H. conjecta by attaching to the left side of the abdomen. Attachment site selection may contribute towards alleviation of intraspecific and interspecific interference competition for larval growing space. 相似文献