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991.
Renal impairment is concurrent with adverse outcomes such as heart disease in humans and dogs. Intrarenal Doppler ultrasonography (IRD) is used to assess intrarenal hemodynamics, and resistance index (RI) and venous impedance index (VII) are used to evaluate intrarenal hemodynamics in humans with heart failure. However, only a few studies have assessed the efficacy of IRD, especially VII, in dogs, and the methods differ between studies. Additionally, repeatability, reproducibility, and factors influencing IRD values have not been validated in dogs. This prospective, analytical study aimed to assess repeatability and reproducibility of IRD, and to clarify influencing factors of IRD in dogs without heart disease. We enrolled 78 dogs without heart disease. The RI and VII were highly reproducible, and the reference intervals for VII were 0.13–0.37. Differences in transducer (sector and convex) and posture (right lateral and supine decubitus position) had no effect on the IRD values. In contrast, RI and VII were higher in the renal vessels than in interlobar vessels. Age affected RI values (r = 0.39, P < 0.001), but there was no correlation between age, body weight, and VII. In conclusion, IRD is a repeatable and reproducible method to assess intrarenal hemodynamics in dogs. The findings also suggest that age should be considered while interpreting RI.  相似文献   
992.
利用染料法荧光定量PCR技术开展功能基因的表达量检测时,表达稳定内参基因的选择和引物的高特异性是确保检测结果准确可靠的前提。本文针对昆虫通用的内参基因NADH (nicotinamide adenine dinucleotide dehydrogenase)和DIMT(dimethyladenosine transferase)在荻草谷网蚜中进行了基因克隆、序列分析、不同龄期的时间表达谱分析和基因表达稳定性评估。两个基因的GenBank登录号分别为OL770461和OL770462。NADHDIMT基因克隆序列与基于高通量测序技术预测结果高度一致,但仍有不同。以β-actin为内参分析两个表达谱,结果显示各自表达稳定、龄期间无显著差异;稳定值由高到低为β-actin,NADH,DIMT,稳定值彼此接近、远小于阈值1.5。以上研究结果说明,通常作为内参基因的持家基因虽然保守,在物种间仍可能存在较大变异,直接引用其他物种的内参引物不可行;不但如此,一代测序技术虽然通量低但准确度极高,与之相比,二代高通量测序则错误率较高,因此引物设计使用的基因应首做克隆测序验证;最后,NADHDIMT在荻草谷网蚜各发育阶段表达稳定,适用于蚜虫基因、特别是不同发育阶段的基因表达差异分析。  相似文献   
993.
标准物质在兽医生物制品质量控制中的应用状况分析   总被引:1,自引:0,他引:1  
探讨了兽医生物制品标准物质的概念及其在生物制品质量控制中的应用状况,分析了我国现阶段兽医生物制品标准物质供应和使用中存在的问题。建议进一步明确有关概念,形成共识,建立科学的兽医生物制品标准体系,分清各有关单位在标准物质供应工作中的责任,努力形成合力共同推进我国兽医生物制品标准物质工作进步。  相似文献   
994.
Mycobacterium avium subsp. paratuberculosis (MAP) causes lesions in naturally and experimentally infected ruminants which greatly differ in severity, cellular composition and number of mycobacteria. Morphologically distinct lesions are already found during the clinically inapparent phase of infection. The complex local host response and number of MAP were characterized at the initial sites of lesions, organized gut-associated lymphoid tissue, in experimentally infected goats. Tissues were collected at 3, 6, 9 and 12 month post-inoculation (mpi) from goat kids that had orally received 10 times 10 mg of bacterial wet mass of MAP (JII-1961). The cellular composition of lesions in Peyer's patches in the jejunum and next to the ileocecal valve was evaluated in 21 MAP-inoculated goats, where lesions were compared with unaltered tissue of six control goats. CD68+, CD4+, CD8+, γδ T lymphocytes, B lymphocytes and plasma cells, MHC class II+ and CD25+ cells were demonstrated by immunohistochemistry in serial cryostat sections.At 3 mpi, extensive granulomatous infiltrates predominated, consisting of numerous epitheloid cells admixed with many CD4 and γδ T lymphocytes. Only single MAP were detected. This indicates a strong cellular immune reaction able to control MAP infection. γδ T lymphocytes were markedly increased in this type of lesion which may reflect their important role early in the pathogenesis of paratuberculosis. At 9 and 12 mpi, divergent lesions were observed which may reflect different outcomes of host–pathogen interactions. In five goats, minimal granulomatous lesions were surrounded by extensive lymphoplasmacytic infiltrates and no MAP were detected by immunohistochemistry. This was interpreted as effective host response that was able to eliminate MAP locally. In three goats, decreased numbers of lymphocytes, but extensive granulomatous infiltrates with numerous epitheloid cells containing increased numbers of mycobacteria were seen. This shift of the immune response resulted in uncontrolled mycobacterial multiplication. Focal and multifocal circumscribed granulomatous infiltrates of mainly epitheloid cells may represent sites of new infection, since they were observed in goats at all times after inoculation. Their presence in goats with minimal granulomatous lesions surrounded by extensive lymphoplasmacytic infiltrates may indicate that despite the local clearance, the infection may be perpetuated.The complex cellular immune reactions postulated for the pathogenesis of paratuberculosis were demonstrated at the local sites of infection. These early host–pathogen interactions are most likely essential for the eventual outcome of the MAP infection.  相似文献   
995.
996.
从国外的经验看,大多数发达国家都是通过制定相应的扶持政策,促进农业机械化发展,在实现农业机械化的基础上实现农业现代化的。目前我国农机化水平总体上仍处于初级阶段,也是政府财政扶持农机化发展的关键时期。因此,应借鉴国际经验,探索农机化财政扶持的新思路、新方法,统筹规划,创新管理体制,优化运行机制,加快我国农机化进程。  相似文献   
997.
风沙区参考作物需水量的计算   总被引:4,自引:0,他引:4  
根据国内外相关的研究成果 ,分析选择并确定了适宜于风沙区参考作物需水量 (ET0 )的计算模式。利用典型风沙区的气象资料 ,对多年逐旬参考作物需水量及 2 0 0 1年春小麦与春玉米生育时段内逐日参考作物需水量进行了分析计算。结果表明 ,FAO最新修正的 Penman-Moteith公式可较好地用于风沙区参考作物需水量的估算 ,一般 ET0 值在年内与年际间变化较大 ,最高值发生在 6月上旬左右 ,多年平均为 5 .82 mm/ d,最低值发生在 1月上旬 ,多年平均 0 .43 mm/ d左右 ,年内各日 ET0 值受气象因素的影响变幅很大 ,因此 ,精确灌溉应设法提高短期天气预报和灌溉预报的精度  相似文献   
998.
普通高等学校本科教学工作水平评估,给二级学院资料室的发展带来了一线生机。阐述了评估前二级学院资料室的现状及存在的问题;评估中,抓住机遇积极开展文献资源的组织建设工作;提出了资料室评估后的发展方向。  相似文献   
999.
我馆参考咨询服务的思考   总被引:5,自引:0,他引:5  
本文集中探讨了图书馆参考咨询服务的各种模式,并结合湖南农业大学图书馆实际情况,对其开展参考咨询服务提出了一些具体的措施。  相似文献   
1000.
本文就“3版”和“4班”分类法在开架阅览室咨询和导读工作中的应用异同进行了探讨,以供广大咨询馆员参考。  相似文献   
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