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111.
The applicability of the recombinant LipL32 for serodiagnosis of leptospiral infection in field rodents was assessed in this study. An immunodominant region of LipL32 was determined by monoclonal antibodies, and then, truncated LipL32 (tLipL32) was designed to contain the region (87–188th amino acid). The tLipL32 was compared between two recombinant expression hosts Escherichia coli and Pichia pastoris in ELISA. With field rat sera, tLipL32 expressed by P. pastoris (tLipL32p) had high antigenicity without background reactions, while tLipL32 expressed by E. coli (tLipL32e) showed high background reactions, which were reduced by pre-adsorption of sera with E. coli. To evaluate tLipL32-ELISA, field rat sera were tentatively divided into a Leptospira infection positive (12 sera) and a negative group (12 sera) based on the results from flaB gene PCR of kidney samples and WB with whole Leptospira cell. Consequently, the sensitivity of tLipL32p-ELISA for field rat sera was 83% . A similar result was obtained from tLipL32e-ELISA with adsorbed sera, (92%). However, sensitivity of tLipL32e-ELISA using sera without an adsorption treatment was 50%. Regardless of the expression host, tLipL32-ELISA had 100% specificity and sensitivity in experimentally infected laboratory rats. These results suggest that recombinant LipL32 expressed by P. pastoris is more applicable for serodiagnosis in field rats due to a lack of background reaction.  相似文献   
112.
OBJECTIVE: The aim of this study was to characterize the clinical and morphologic features of neuronal ceroid lipofuscinosis (NCL) in the Polish Owczarek Nizinny (PON) breed of dog. ANIMALS: Nine Swedish PON dogs of both sexes were included in the study. PROCEDURE: All dogs underwent a detailed clinical evaluation, with emphasis on ophthalmic exams. Histopathology and electron microscopy were performed on the eyes, brain and various internal organs. Immunohistochemical staining for detection of sphingolipid activator proteins (SAPs) and mitochondrial ATP synthase (SCMAS) was performed on the eyes and brain. RESULTS: The dogs showed behavioral abnormalities, motor disturbances and visual impairment or blindness. Pupillary responses were abnormal while fundus changes varied from normal to severe retinal atrophy. Electroretinography (ERG) showed variable changes, from slight alterations in the process of dark adaptation to severely reduced or nonrecordable ERG a- and b-wave amplitudes. Histopathology revealed intracytoplasmic storage bodies within neurons of the brain and in retinal cells, especially the retinal pigment epithelium (RPE). Round to oval granular type of inclusion bodies, known as granular osmiophilic dense deposits (GRODS), were found in neuronal cells in the brain and in the retina. Immunohistochemistry identified the storage material in the brain and retina as consisting of SAPs. CONCLUSION: The presently described NCL disease in PON dogs shows similarities to previously recorded cases in the Miniature Schnauzer. The closest human equivalent to this disease is infantile NCL (CLN1), in which the major stored proteins are SAPs and the ultrastructure of the inclusion bodies of neuronal cells is granular.  相似文献   
113.
抗微生物药物在保障动物健康和食品安全方面发挥了重要作用,为了应对日益严峻的微生物耐药性问题,动物源微生物耐药性监测是应对微生物耐药性风险的重要防控策略。在“同一健康体系”工作框架下,中国和美国积极进行动物源微生物耐药性监测。本文通过对比研究中美动物源微生物耐药性系统的监测设计、监测对象和监测数据应用情况,结合我国畜牧兽医行业现状,立足我国动物源微生物耐药性监测客观需求,旨在为我国动物源微生物耐药性监测工作提供参考。  相似文献   
114.
经济绿肥覆盖对西双版纳胶园土壤性状的综合影响   总被引:1,自引:0,他引:1  
论述了经济绿肥覆盖对提高土壤肥力、改善土壤物理性状、水土保持、提高抗病性、增加收入等方面的作用和重要意义。阐明了经济绿肥覆盖在西双版纳胶园的应用前景,它将实现经济效益和生态效益并重的胶园可持续发展。同时提出了在胶林行间特别是保护带陡坡地种植绿肥覆盖物的发展思路及相应措施,即完成胶园经济绿肥良种的筛选、经济效益和生态效益评价、及配套栽培技术试验示范。  相似文献   
115.
116.
To research the problem of plastic art design and emulation of products with the virtual reality technology can short the product development cycle and reduce the cost. This paper discusses the information based on the product feature ,solid model with parameters, the structure and function of this system. Combined the product properties with its solid model. Proposed a method with CAD to create the model of the product based on features in the product design. Expressed its feature parameter and shape of model fully .In the case for a deceleration box the feature model has solved the problem of physical information ,geometry information and the informative process in its production management system efficiently.  相似文献   
117.
This paper presents the end-effect factor of Synchronous motor with cylindricalsolid rotor offered by analysing the 3-D electromagnetic field and using the Poynting vector.To ap-ply it in an actual calculation,the end-effect factor is proved correct and applicable.  相似文献   
118.
To embed or heap industry solid wastes somewhere will occupy the earth and pollute the environment seriously. So utilizing the industry solid wastes as regeneration resource is important for sustainable development of city. Based on application and research for years in utilizing industry wastes and widely investigation, the produce status of industry solid wastes in Chongqing such as fly ash, desulfuration gypsum, blastfurnace slag and chromium slag are introduced. At the same time,this paper introduces application and research on these wastes in field of building material in Chongqing. Analyze problems and countermeasures during utilizing industry solid wastes as regeneration resource in Chongqing. As a further the prospect of utilizing industry solid wastes as regeneration resource of building material is discussed.  相似文献   
119.
In this paper, according to the study on a great number of experiments and data analyses, the sedimentation rule of solid particles in debris flow is set up. Three main factors that influence the particle sedimentation in debris flow were studied; the basic reasons to influence the particle sedimentation were analyzed. The particle sedimentation in debris flow could be divided into three stages,i, e. the starting stage, the quick sedimentation stage and the accumulation stage,and detailed analysis on the sedimentation process each stage was made. The liquid viscosity, particle quality and additional water pressure have an important role on the sedimentation rule of the particle in debris flow.  相似文献   
120.
农田土壤含水率与坚实度快速信息采集系统   总被引:1,自引:0,他引:1  
介绍了一种农田土壤含水率与坚实度快速信息采集系统.本系统包括土壤介电传感器、圆锥指数传感器及深度传感器,可以快速、同步、实时地获得0~500mm范围内土壤剖面含水率与圆锥指数信息.同时,本系统还结合了GPS和GIS技术,实现了土壤参数的空间分析,可以更方便地把系统应用于农田信息管理.本系统为实现土壤水分和坚实度的同步测量搭建了一个智能化的试验平台,并且在与德国波恩大学农业工程研究所的合作中成功地应用于田间测量.  相似文献   
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