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1.
用ELISA从感染16h后的菜青虫血淋巴中检出颗粒体病毒,检出率为48%,检出率随感染时间延长而递增,感染后24h高达80%以上,远早于感染病症出现的时间,用血淋巴检测优于组织提取液,阳性滴度高,以1头虫检测较多头虫好,试验证明ELISA比对流免疫电泳灵敏。  相似文献   

2.
本文从大体观察、显微观察和超微结构等方面对感染苏云金芽孢杆菌后的菜青虫幼虫进行了组织病理学研究。菜青虫在摄入苏云金芽孢杆菌后立即停食,30分钟后就在中肠上皮细胞中发现线粒体的脊内空间扩大、粗面内质网局部膨胀,微绒毛开始膨大并部分溶解。感染后1—2小时可见中肠上皮细胞靠近微绒毛一方出现较大的空泡,线粒体的空间进一步扩大,内质网的网膜慢慢分离。到第4小时,中肠上皮细胞的病变加剧,显微镜下看到细胞开始解体,电镜观察到线粒体开始破裂,内质网膜糊断裂。以后细胞迅速解体,到第8小时仅存基底膜,但其它组织基本完整。第10小时以后,观察到基底膜开始破裂,细菌进人血腔.脂肪体肌肉等组织均遭破坏,此时幼虫中部渐渐变黑,下痢并开始死亡。  相似文献   

3.
用双相法提纯青虫菌(Bacillus thuringiensis var.galleriae)的晶体,碱解后免疫家兔获晶体蛋白抗体,然后用纯化的晶体感染莱青虫,半小时至1小时取中肠上皮细胞作酶标电镜观察,结果表明仅在细胞膜上看到抗原的存在。  相似文献   

4.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

5.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

6.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

7.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

8.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

9.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

10.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

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