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1.
基于高通量的转录组测序,为大量并快速的开发分子标记提供契机。本研究对紫草科植物疏花软紫草进行转录组测序,共得到92042086条reads,从疏花软紫草158446个Unigene中搜索到332个低拷贝核基因。为进行多态性验证,从中随机挑选30个设计引物,并对3个疏花软紫草种群共9个个体进行PCR扩增,结果发现其中16对引物能够扩增出单一稳定的目的条带,从中随机挑选7个片段进行群体测序并计算DNA多态性。结果表明,7对引物的多态性位点平均值为657,单倍型平均值为514,单倍型多态性 (HD) 在0389~0944之间,核苷酸多态性 (Pi) 为000148~001723。通过转录组测序技术开发的低拷贝核基因有较高的多态性,且可以有效地运用于群体遗传学和谱系地理学研究中。另外,这些低拷贝核基因能够被运用于软紫草属植物系统发育重建以及物种形成等研究工作中。 相似文献
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MARCY J. SOUZA JONATHAN S. WALL ALAN STUCKEY GREGORY B. DANIEL 《Veterinary radiology & ultrasound》2011,52(3):340-344
Positron emission tomography (PET) is often used to stage and monitor human cancer and has recently been used in a similar fashion in veterinary medicine. The most commonly used radiopharmaceutical is 2‐Deoxy‐2‐[18F]‐Fluoro‐d ‐glucose (18F‐FDG), which is concentrated and trapped within cells that use glucose as their energy substrate. We characterized the normal distribution of 18F‐FDG in 10 healthy Hispaniolan Amazon parrots (Amazona ventralis) by performing whole body PET scans at steady state, 60 min after injection. Significant variability was found in the intestinal activity. Avian species are known to reflux fluid and electrolytes from their cloaca into their colon. To evaluate reflux as the cause of variability in intestinal distribution of 18F‐FDG, dynamic PET scans were performed on the coelomic cavity of six Hispaniolan Amazon parrots from time 0 to 60 min postinjection of radiotracer. Reflux of radioactive material from the cloaca into the colon occurred in all birds to varying degrees and occurred before 60 min. To evaluate the intestinal tract of clinical avian patients, dynamic scans must be performed starting immediately after injection so that increased radioactivity due to metabolism or hypermetabolic lesions such as cancer can be differentiated from increased radioactivity due to reflux of fluid from the cloaca. 相似文献
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L. Marconato V. Marchetti D. Francione C. Masserdotti M. Gregori R. Leotta F. Abramo 《Veterinary and comparative oncology》2008,6(3):162-170
Canine cutaneous mast cell tumours (MCTs) have a variable biologic behaviour, and accurate staging is necessary to dictate therapy and predict outcome. Regional lymph node (RLN) involvement is a relevant prognostic factor. While obvious lymph node (LN) metastases are relatively easy to be diagnosed, micrometastatic disease recognition is challenging. The main aim of the study was to evaluate the number of mast cells (MCs) in the LNs of clinically healthy dogs ( n = 4, group 1), dogs with inflammatory diseases ( n = 31, group 2) and dogs with cutaneous MCT ( n = 27, group 3), including animals with no RLN metastases (subgroup 3.1), those with occasional MCs in RLNs (3.2) and those with obvious RLN metastasis (3.3). MCs also were morphometrically evaluated for the following nuclear parameters: mean nuclear area (MNA), mean nuclear perimeter (MNP), largest to smallest diameter length (LS ratio), mean nuclear form factor and coefficient of variation of nuclear area. The average percentages of MCs were 0.0 and 0.01 in groups 1 and 2, respectively, and 0.07, 2.4 and 47.1 in subgroup 3.1, 3.2 and 3.3. MNA and MNP were significantly higher in subgroup 3.3 than in group 2 ( P < 0.05). MNA and MNP in subgroup 3.2 suggested the presence of neoplastic MCs; this prediction of micrometastatic load correlated with outcome. Analysis of preliminary results shows that nuclear morphometry is useful to detect micrometastatic disease in RLN of dogs bearing cutaneous MCTs. 相似文献
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采用自体器官移植的思路,探索用自体部分带蒂空肠代替尿道的手术方法,以解决实际中动物因尿道结石、尿道损伤等所致的自身尿道无法正常排泄尿液的情况。经过术后观察,犬的各项生理指标均趋于正常。结果表明,此段带蒂空肠可存活,并可代替尿道,保证机体正常的尿液排泄,为犬的尿道再造术提供了一种新的方法。 相似文献
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Navicular disease is unlikely to be a single disease. The close anatomical and functional relationships between the navicular bone, collateral sesamoidean ligament, distal sesamoidean impar ligament, deep digital flexor tendon, navicular bursa and distal interphalangeal joint result in the frequent occurrence of combinations of injuries. There are a number of different pathological processes that affect the navicular bone, which probably have different aetiopathogeneses. While there is strong evidence that biomechanical forces may result in failure of functional adaptation and excessive modelling, it is likely that each disease or injury type has a multifactorial cause. 相似文献
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供体年龄对德国肉用美利奴羊超数排卵及胚胎移植效果的影响 总被引:2,自引:0,他引:2
提高绵羊体内胚胎生产的效率对促进优良品种扩繁及良种推广具有重要意义。为充分利用不同年龄段良种德国肉用美利奴羊,试验选用青年(18月龄,配种未受胎)、老龄(60~72月龄,经产)以及幼龄母羊(7月龄,性成熟前)做供体,用改进的程序进行超数排卵,研究供体年龄与超数排卵和胚胎移植效果的关系。结果表明:①青年、老龄组母羊超排后只均可用胚数分别为10.9枚、10.3枚,显著高于幼龄母羊的6.0枚。青年、老龄组母羊的胚胎经移植后受胎率分别为71.6%、58.3%,显著高于幼龄组的41.7%。②幼龄、青年组回收的胚胎中囊胚所占比例显著高于老龄组,说明幼龄、青年组供体的胚胎发育速度显著快于老龄供体。③青年、老龄组母羊超排前预注小剂量FSH,卵巢黄体数目明显增多,说明能提高超排效果。本试验优化了德国美利奴羊的超排程序,证明年龄显著影响德国美利奴羊的超排效果及胚胎质量,为进一步提高绵羊胚胎移植效率提供了参考依据。 相似文献
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为了探讨桦褐孔菌多糖对急性感染弓形虫小鼠核转录因子c-Jun、IL-1β和IL-12的影响,本试验在建立急性感染弓形虫小鼠模型后,随机将其分成3组:阴性组、急性感染弓形虫小鼠模型组和桦褐孔菌多糖试验组。采用RT-PCR法检测肝组织中c-Jun及脾组织中IL-1β和IL-12的mRNA表达;Western blot法检测c-Jun蛋白的表达。结果显示:c-Jun、IL-1β和IL-12的mRNA分别在360、736和978 bp处扩增出单一电泳条带,且c-Jun蛋白在39 ku处表达,均呈现出弓形虫感染组表达量最高,桦褐孔菌多糖试验组次之,对照组最弱。说明桦褐孔菌多糖可能通过下调c-Jun过度表达,抑制IL-1β、IL-12的过度表达,部分阻抑了AP-1信号通路转导,从而减轻炎症反应,达到抗弓形虫感染的目的。 相似文献