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51.
Functional imaging using positron emission tomography (PET) plays an important role in the diagnosis, staging, image‐guided treatment planning and monitoring of malignant diseases. PET imaging complements conventional anatomical imaging such as computed tomography (CT) and magnetic resonance imaging (MRI). The strength of CT scanning lies in its high spatial resolution, allowing for anatomical characterization of disease. PET imaging, however, moves beyond anatomy and characterizes tissue based on functions such as metabolic rate. Combined PET/CT scanners were introduced commercially in 2001 and a number of technological advancements have since occurred. Radiolabelled tracers such as 18F‐fluorodeoxyglucose (FDG) and 18F‐fluorothymidine (FLT) allow visualization of various metabolic processes within cancer cells. Many studies in human oncology evaluating the utility of PET/CT have demonstrated clinical benefits. Few veterinary studies have been performed, but initial studies show promise for improved detection of malignancy, more thorough staging of canine cancer and determination of early response and disease recrudescence.  相似文献   
52.
The detection of 4-hydroxycoumarin rodenticides in poisoned domestic animals requires a highly sensitive method as tissue and serum levels of anticoagulants may be very low owing to rapid elimination, metabolism or post-mortem degradation. Thin-layer chromatography (TLC) and reversed-phase high-performance liquid chromatography (RP-HPLC) with fluorescence detection were used to identify the anticoagulants in spiked tissues and in suspicious samples. The analysis of ten suspicious samples highlighted the limitations of both methods. Only the three samples of baits were found positive by TLC whereas one of the five anticoagulants was detected in eight samples by RP-HPLC with fluorescence detection. Therefore, RP-HPLC with fluorescence detection proved to be the more sensitive method for detecting low levels of 4-hydroxycoumarins in blood serum, liver and ingesta, whereas TLC is usually sufficient for analysing baits.Abbreviations RP-HPLC reversed-phase high-performance liquid chromatography - TLC thin-layer chromatography  相似文献   
53.
The reproductive physiology of the impala was studied in the Kruger National Park. The data concerning the hypophysial hormones, the androgenic hormones and ovarian histology are discussed in relation to the behaviour of the animal.

It was found that the male animal shows the most profound behavioural changes which occur during the mating season. These changes are induced by an increase of interstitial cell-stimulating hormone which leads to an increase in androgenic hormone. The female shows relatively few behavioural changes during the mating season, the only change being at the time of oestrus.

On the basis of the data presented and information reported for domestic animals, it is postulated that the behaviour of the male impala plays an important role in determining the breeding season.  相似文献   
54.
Eight strains of Taylorella equigenitalis were identified by a polymerase chain reaction using a primer pair specific to the 16S rDNA of T equigenitalis. These eight strains were chosen because they had previously been shown to represent eight distinct genotypes by pulsed-field gel electrophoresis analysis after separate digestion of the genomic DNA with ApaI or NotI. The eight strains could be classified into six or seven types by random amplified polymorphic DNA analysis using different kinds of primers. Amplified rDNA restriction analysis after separate digestion with five restriction enzymes, including AluI and MboI, of the 1,500 bp fragments of rDNA amplified by polymerase chain reaction did not discriminate the genomic variations among the eight strains of T equigenitalis. Thus, pulsed-field gel electrophoresis was shown to discriminate these eight organisms better than random amplified polymorphic DNA analysis, while amplified rDNA restriction analysis was found to be unsuitable for subtyping T equigenitalis.  相似文献   
55.
为了提高葡萄园资源利用率和综合效益,构建了牧草-鹅-鲜食葡萄循环生态种养体系。实践表明,在设施葡萄园推广套种牧草养鹅、鹅粪生产有机肥料、有机肥料种植葡萄和牧草等高效配套技术,取得了良好的经济效益、生态效益和社会效益。实施牧草-鹅-鲜食葡萄循环生态种养是江苏沿海地区发展现代农业的一种有效生产模式。  相似文献   
56.
票据无因性是指票据基础关系与票据法律关系的分离。它能保证持票人(尤其是正当持票人)的利益,促进票据流通的效率。文章从票据无因性最基本的概念出发,针对有关票据无因性的争论中出现的几种不同观点进行阐述和分析,并对我国票据立法中所体现的票据无因性原则进行分析和思考。  相似文献   
57.
山黧豆低毒品种的筛选及栽培利用技术研究   总被引:1,自引:1,他引:1  
对国内外引进的65个山黧豆品种,经3年观察和农艺性状的测定以及β-草酰氨基丙酸(BOAA)、营养成分的分析,筛选出产量,蛋白质含量高,毒素含量低,经毒理学实验为安全饲用的黑龙江山黧豆-1,黑龙江山黧豆-2,西德山黧豆3个品种供生产中应用,还针对山黧豆作为饲草(料)推广应用中的播种量,磷肥施用量,压青及根茬肥效等栽培利用措施进行了探讨。  相似文献   
58.
对我省流行的疑似猪病毒性腹泻进行了病原诊断,通过细菌培养、RNA电泳和电镜形态观察等辅助诊断和免疫萤光特异性诊断,确诊该病病原为猪传染性胃肠炎病毒(TGEV)与猪流行性腹泻病毒(PEDV)的混合感染,混合毒代号为TPV3。  相似文献   
59.
试验以新鲜猪粪为发酵原料,研究湿法和干法两种不同厌氧发酵过程的碳、氮排放量。湿发酵和干发酵组发酵料液的总固体(TS)含量分别为8%和20%,发酵液pH为6.8~7.4,发酵温度为35℃,体积为1.2 L,周期为21 d。试验期间每天测产气量,每4天取发酵样,测其全氮含量和TS降解率。结果表明,湿法和干法发酵组的CH4总产气量分别为9114 mL和12537 mL;CO2的总产气量分别为251.90 mmol和343.67 mmol;TS降解率分别为52.5%和29%。湿发酵的碳流失率和全氮流失率极显著高于干发酵(P<0.05)。  相似文献   
60.
用含2mol/L尿素的磷酸盐缓冲液以热处理方法提取的K99和F41菌毛作为抗原,对琼脂扩散试验方法进行研究。结果表明本试验方法简便,特异性强,敏感性高,可用于血清抗体检测;所制备的抗原稳定、重复性好。  相似文献   
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