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Previously, we have reported that the injection of an expression vector containing Herpes simplex virus (HSV) Glycoprotein D-1 (gD-1) generated a significant antibody response in mice and protected them against HSV lethal challenge. We tested its potential to induce antibody and cell mediated immune responses in latently infected mice. Positive control group (KOS) and HSV gD-1 vaccinated mice demonstrated protection against a lethal ocularly challenge of 10(5.5) plaque-forming units (pfu)/eye of wild HSV-1 versus negative control groups. For neutralizing antibody titers, delayed-type hypersensitivity (DTH), lymphocyte proliferation responses, clinical evaluation and survival following lethal challenge, no considerable difference was observed between mice vaccinated with DNA plasmid and those vaccinated with KOS. KOS-vaccinated mice demonstrated the ability to completely prevent latency whereas DNA vaccinated group showed some degree of protection and displayed less latency than negative control groups and had considerably high levels of IFN-gamma and strong CTL responses versus negative control groups. It can be concluded that although immunization with the DNA vaccine is more effective in both protecting mice and induction of immune response, however it could not completely block the latent infection in sensory nerves.  相似文献   
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The prevalence of Theileria equi infection as well as the environmental and demographic risk factors for infection was studied in 590 healthy horses from 46 farms in Israel. The prevalence of T. equi DNA was assessed using a polymerase chain reaction for a segment of the Theileria 18S rRNA gene. The overall prevalence was 26.4% (156/590). There was a significant geographical variation in the prevalence of T. equi infection, ranging from 9.3% (25/270) in the central lowlands to 81.7% (49/60) in the Golan Heights. The prevalence of T. equi infection was found to be significantly associated with management types with more horses with access to pasture being positive. Breed was identified as a risk factor for T. equi infection in a univariate analysis with relatively high infection rates in the Quarter horse and local breeds (41.1% and 36.3% respectively), while ponies and Arabian horses had a relatively low prevalence (10% and 9.1%, respectively). However, since a correlation between geographic location and breed was found, it is difficult to draw definite conclusions regarding this risk factor. Age and gender were not found as risk factors for T. equi infection in this study. The environmental variables that were significantly associated with positivity were relative humidity and minimum land surface temperature at day which both showed negative correlation with T. equi prevalence. In conclusion, Israel was found to be enzootic for T. equi infection, as indicated by the high sub-clinical infection rate, which differed between geographical areas.  相似文献   
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Thrombelastograph analyzers are point-of-care hemostatic analyzers that provide global assessment of the hemostatic process. Thrombelastography (TEG) detects and provides a continuous recording of the changes in the viscoelastic properties of whole blood from initial clot formation through fibinolysis. TEG has been validated for use in dogs, horses, and cats. Hemostasis research using TEG has focused on test validation, alterations of TEG tracings in animals with naturally occurring diseases, and the use of TEG for monitoring various therapeutic modalities. This article reviews TEG methodology and terminology, including potential sources of preanalytical and analytical errors, the correlation between TEG and other routine hemostatic assays, and current clinical applications of TEG, with emphasis on veterinary medical practice. Data suggest that TEG may be a sensitive and useful adjunctive tool for evaluating an animal with an underlying coagulopathy, including hypercoagulability and hypocoagulability. Additional prospective studies are needed to (1) correlate TEG tracing patterns with a clinical predisposition for bleeding or thrombosis in various disease states and (2) determine whether monitoring and treating hemostatic disorders based on TEG tracings improve clinical outcome.  相似文献   
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Pollen and trichome morphology of the genus Betula were evaluated from three main habitats in Iran using light and electron microscopy.Pollen types were identical and tri-porate;however,in terms of quantitative data,some differences were observed in exine(outside)wall thickness,length of polar axis and length of equatorial axis,possibly due to the environment.Pollen alone is insufficient to separate species of Iranian birch.Investigation of the trichome trait(small hairs or other outgrowths)revealed that birch species in Iran belong to:(1)Betula litwinowii Doluch.according to the low density of trichomes on the adaxial surface of the leaves and the lack of trichomes on the abaxial surface and many trichomes on the petioles;(2)Betula pendula Roth.due to the absence of trichomes on the adaxial surface and the low density of trichomes on the abaxial surface;and,(3)in the adaxial and abaxial surfaces of leaves and petioles,the trichomes had different types of pilose(long,soft hairs),and this strengthens the possibility of a different species or more likely a hybrid of B.pendula.  相似文献   
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One myrsinol-type diterpene ester (1) isolated from Euphorbia decipiens was evaluated for analgesic activity in the acetic acid induced writhing test in mice. Different dose (5-20 mg/kg i.p.) of the compound showed significant antinociceptive activity, which was comparable to standard analgesic drugs, aspirin and ibuprofen (100 mg/kg i.p.).  相似文献   
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The effects of high temperature stress and supplemental irrigation on seed yield and water use efficiency (WUE) of canola (Brassica napus L.) were studied in a field experiment conducted for 2 years. The experiment was a randomized complete block design arranged in split plot, conducted at Agricultural Research Station of Gonbad, Iran. It was arranged in two conditions, i.e. supplemental irrigation and rainfed. Two cultivars of canola (Hyola401 and RGS003) as subplots were grown at five sowing dates as main plots. The sowing dates were 9 November, 6 December, 5 January, 4 February and 6 March in 2005-2006 and 6 November, 6 December, 5 January, 4 February and 6 March in 2006-2007, to have a wide range of environmental conditions around flowering and seed filling periods, and to coincide reproductive stages of the crop with high temperature stress. Seed yield was improved due to field management practices, such as supplemental irrigation and optimum sowing date. Supplemental irrigation was an efficient practice to mitigate water stress, and to increase aboveground dry matter and seed yield. There was a strongly negative relationship between seed yield and air temperature during reproductive stages. Delay in sowing led to more rapid developmental of canola, decreased aboveground dry matter, leaf area index (LAI), harvest index (HI), WUE, and seed yield. Achieving a high aboveground dry matter was an essential prerequisite for high reproductive growth and a high seed yield. Greater seed yield and WUE at first sowing date were associated with greater LAI and aboveground dry matter, and lower temperatures during reproductive stages. The results support the view that WUE can be used as an indirect selection criterion for seed yield in genotypic selection.  相似文献   
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为了提高车辆操纵稳定性,提出一种后轮主动脉冲转向控制策略,并对此做了理论分析和试验研究。基于试验Lexus车辆分析脉冲转向系统对车辆稳定性能的影响并确定最优的主动转向脉冲参数。设计了控制策略结构与算法,基于Car Sim和Simulink联合仿真分析,验证所提控制方法的有效性。基于试验Lexus车辆,安装液压脉冲转向系统并进行整车试验研究,验证后轮脉冲转向的实用性。仿真和试验结果表明:质心侧偏角和侧向加速度在峰值处分别减小了46.8%、23.5%,提高了汽车的横向稳定性;侧倾因子能控制在设定的阈值范围[-0.8,0.8],车辆侧倾角减小了25.4%,能有效改善车辆防侧翻能力,且展现出比后轮主动转向更好的控制效果。  相似文献   
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