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51.
简述了猪肾脏局灶性病变的病变形态及分布情况,对病变部位进行综合性检查,指出病理学诊断的主要依据;同时对该病进行涂片镜检、分离培养、肉汤培养等实验室诊断,结果表明:该病灶多发生在六、七月份,并多发在当日进库次日屠宰的猪中,系由巴氏杆菌引起的猪肾脏局灶性病变。 相似文献
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Celina Y. Morimoto Monique N. Mayer Narinder Sidhu Rachel Bloomfield Cheryl L. Waldner 《Veterinary and comparative oncology》2020,18(2):199-205
Sources of residual setup error after image guidance include image localization accuracy, errors associated with image registration, and inability of some treatment couches to correct submillimeter translational errors and/or pitch and roll errors. The purpose of this experimental study was to measure setup error after image‐guided correction of the canine intracranial region, using a four degrees‐of‐freedom couch capable of 1 mm translational moves. Six cadaver dogs were positioned 45 times as for clinical treatment using a vacuum deformable body cushion, a customizable head cushion, a thermoplastic mask and an indexed maxillary plate with a dental mould. The location of five fiducial markers in the skull bones was compared between the reference position and after megavoltage (MV), kilovoltage (kV) and cone‐beam computed tomography (CBCT)‐guided correction using orthogonal kV images. The mean three‐dimensional distance vectors (3DDV) after MV, kV and CBCT‐guided correction were 1.7, 1.5 and 2.2 mm, respectively. All values were significantly different (P < .01). The 95th percentiles of the 3DDV after online MV, kV and CBCT‐guided correction were 2.8, 2.6 and 3.6 mm, respectively. Residual setup error in the clinical scenario examined was on the order of millimetres and should be considered when choosing PTV margins for image‐guided radiation therapy of the canine intracranial region. 相似文献
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水稻类病变突变体lrd40的抗病性与细胞学分析 总被引:2,自引:0,他引:2
由中花11经γ射线诱变获得的水稻类病变突变体lrd40,是一个对环境不敏感的全生育期表达的突变体。遗传分析表明,lrd40的类病变性状为1个隐性位点控制,与已报道的类病变突变体lrd38、lrd39、lrd42是非等位的。经多点接种试验,lrd40对水稻白叶枯病2个菌系PXO99A和DY89031都表现抗病。lrd40与野生型杂交F2接种结果证实,lrd40的抗白叶枯病与类病变的表现是一致的。锥虫蓝(trypan blue)染色观察到lrd40的类病变发生可能是一个程序性细胞死亡过程,经二氨基联苯胺(diamino benzidine,DAB)染色检测到lrd40的类病变表达时,叶片上产生H2O2沉淀。细胞学观察结果说明,lrd40的类病变发生类似于植物防卫反应的早期特征,如细胞死亡和过敏反应导致的氧迸发(oxidative burst)。 相似文献
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Spot blotch, caused by Bipolaris sorokiniana, has become an increasingly important disease on barley in Sweden. In order to enhance our knowledge of this disease, eight Swedish B. sorokiniana isolates were assessed for their virulence pathotype on 30 barley genotypes including eight lines of mutant origin, designated B. sorokiniana tolerant (bst). A leaf screen assay revealed the presence of virulence groups 1 and 7 in Sweden. Several mutant genotypes demonstrated enhanced resistance responses (P = 0.0001), of which bst1:3 had the lowest leaf scoring value to the most virulent isolate, Swe2 (virulence group 7). To evaluate the host root responses, two contrasting isolates Swe2 and Swe4 (virulence group 7 and 1) were used to inoculate a set of eight differential lines, including four promising mutant lines from the leaf screen. Mutant bst1:6 was significantly less susceptible (P = 0.001) compared with the other barley genotypes tested, independent of the two isolates used. Mutants bst1, bst1:3 and bst1:4, which displayed less or no spots, are also considered promising genotypes for further breeding attempts. 相似文献
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目的:探讨CT引导下经皮肺穿刺活检的临床应用。方法:对42例肺周围性结节或肿块病人行CT引导下经皮肺穿刺活检,采用COOK公司18G自动弹射活检枪,CT定位下选择最佳层面进针行至少两点取材,活检后行组织学及细胞学检查。结果:穿刺成功率为100%,总阳性率为76.2%,假阴性率9.52%,穿刺后气胸发生率为7.14%,咯血发生率为9.52%,胸痛发生率为16.67%。结论:CT引导下经皮肺穿刺活检成功率高、准确性高、并发症少,是一种简单、安全、有效的诊断方法,值得临床推广应用。 相似文献
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Sakae ARASE Chang-Min ZHAO Kazuya AKIMITSU Mikihiro YAMAMOTO Masahiko ICHII 《Journal of General Plant Pathology》2000,66(2):109-116
A gamma-ray-induced rice mutant, M1009, which spontaneously forms brown specks on leaves was isolated. In appearance, these
lesions very much resemble those that are produced during the hypersensitive resistance response of rice to pathogens. A similar
phenotype has been associated with a number of mutants in maize or Arabidopsis, which have been briefly categorized as disease lesion mimics. Brown speck formation was suppressed at temperatures of 25°C
and above, and was severe at 20°C. Light irradiation is also required to initiate brown specks. In addition, the mutant exhibits
heightened resistance to two major fungal pathogens of rice, Magnaporthe grisea and Cochliobolus miyabeanus. Genetic characterization of the mutant has indicated that its les-bs (lesion-brown speck) phenotype segregates as a monogenic
recessive mutation.
Received 13 September 1999/ Accepted in revised form 15 December 1999 相似文献
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重组表达猪传染性胸膜肺炎放线杆菌6种主要毒力因子基因:apxⅠ、apxⅡ、apxⅢ、apxⅣ、apfa和omp,以重组蛋白rApxⅠ、rApxⅡ、rApxⅢ和rOMP组合免疫小鼠作为试验I组,重组蛋白rApxⅠ、rApxⅡ、rApxⅢr、OMPr、ApxⅣ和rApfa组合免疫小鼠作为试验Ⅱ组,PBS为对照组,分3次免疫小鼠,采用背部皮下多点注射,每次间隔2周,免疫剂量为0.2 mL/只,3免后1周分别以APP1型菌Shope 4074株(5×109cfu)和APP2型菌S1536株(5×1010cfu)进行攻毒试验。通过小鼠保护率与抗体效价的相关性研究、肺部病理变化及肺脏细菌的分布情况等指标进行综合评价。结果显示,试验Ⅰ组4种重组蛋白特异性抗体水平显著高于其他两组(P<0.05),对APP1型菌攻毒的保护率(9/10)明显高于试验Ⅱ组(5/10)和对照组(0/8),小鼠的免疫保护率与抗体效价之间存在显著正相关;且该组对APP2型菌攻毒的保护作用(无肺脏损伤)也明显优于其它两组(典型肺部损伤)。间接免疫荧光试验表明试验Ⅰ组对肺脏细菌的清除效果也明显优于其他两组。本试验揭示试验Ⅰ组对不同血清型APP攻击能够提供很好的交叉保护作用,从而为猪传染性胸膜肺炎新型疫苗的研制提供参考。 相似文献