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41.
Utility of two‐view vs. three‐view abdominal radiography in canines presenting with acute abdominal signs
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![点击此处可从《Veterinary radiology & ultrasound》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Marina V. Mavromatis Mauricio Solano Michael Y. Thelen 《Veterinary radiology & ultrasound》2018,59(4):381-386
There are clear differences in the normal radiographic appearance of the abdominal organs between a left lateral vs. a right lateral view. While a few veterinary academic institutions have transitioned to a three‐view abdominal radiographic study protocol, obtaining only two views of the canine abdomen remains the current standard in veterinary medicine. In this combined retrospective and prospective, case‐controlled study, 48 canine patients presenting with signs of acute abdomen were recruited. Four board‐certified veterinary radiologists and four general practice veterinarians with greater than 3 years of experience in small animal practice were asked to determine if 10 predetermined findings were present within the set of images and if surgery was recommended based on those findings. Image readers were unaware of the clinical history. Three‐view studies did not yield statistically significantly greater accuracy than two‐view studies when evaluating all readers together. No statistically significant associations between the availability of the third view and increased accuracy or confidence were found in evaluations of general practitioners specifically. Evaluation of three‐view radiographic examination, as compared to two‐view examination, did not have perceived or statistically significantly increased diagnostic utility. Based on our findings, there is no statistically increased utility to justify a standard three‐view abdominal radiographic examination over a two‐view study for canines presenting with signs of acute abdomen. 相似文献
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紫外线(UV)照射禾顶囊壳生物学效应的研究 总被引:3,自引:0,他引:3
紫外线照射禾谷顶囊壳(Gaeumannomycesgraminisvar.Tritici)的子囊孢子,孢子存活率随照射剂量的增加而呈指数下降,剂量效应关系式符合S=e^-λD(S为存活率;D为照射剂量)。受UV照射后,孢子萌发率也随照射时间增加呈指数下降,处理孢子可产生各种畸形芽管,形态正常的芽管也较对照生长缓慢,研究结果还表明,紫外照射后,病菌出现细胞壁破裂和细胞质外渗现象,这种现象随着照射剂量 相似文献
45.
Surface Breaking Behaviour in a Population of Captive Rays Raja: The Expression of a Need to Forage?
Observations were made of the surface breaking behaviour of a population of captive rays Raja. The behaviour was found to
have a temporal link with a scheduled feeding event, and to be most common in animals assumed to be hungry. It is suggested
that the behaviour is appetitive and is a method of foraging appropriate to the captive situation.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
46.
对伊犁河雅玛渡河段2010年1~4月采集的39尾伊犁裂腹鱼[Schizothorax (Racoma) pseudaksaiensis (Herzenstein)]样本进行了体表鳞片、臀鳞、脊椎骨、耳石和背鳍条共5种年龄鉴定材料的年轮特征研究。结果表明,体表鳞片没有明显的年轮特征,不能作为年龄鉴定材料,其他4种材料可作为伊犁裂腹鱼的年龄鉴定材料。样本为2+龄时,4种年龄材料鉴定结果的吻合率为100%;3+和4+龄鉴定结果吻合率较高,分别是87.3%和85.4%;5+~8+龄个体吻合率较低,为63.9%。伊犁裂腹鱼3+龄以上个体进行年龄鉴定时不能仅用1种鉴定材料,而应以耳石为主,其他年龄材料为辅。 相似文献
47.
用电镜X射线显微分析法,研究铜在鲤(Cyprinus carpio)肝细胞和肾细胞中的分布和相对含量,从细胞水平探讨鲤的铜中毒机理。结果表明,铜进入鲤体内后,在肝细胞、肾细胞的溶酶体中分布最多,溶酶体旁、细胞核次之,细胞质内最少,中毒组与正常组差异显著。鲤中毒后肝细胞核膜扩张、线粒体呈空泡状,溶酶体数量增多、体积增大;肾小管上皮细胞核膜扩张,线粒体肿胀,嵴断裂。 相似文献
48.
Many forest ecosystems in Germany are strongly influenced by emissions of pollutants like SO2 and alkaline dusts. To quantify and evaluate the consequences of long‐term fly ash deposition on forest soils, a study was conducted in pine stands (Pinus sylvestris) in the Dübener Heide in Northeastern Germany. This forest area has been influenced mainly by emissions from coal‐fired power plants and the chemical industry of the industrial region Bitterfeld‐Wolfen‐Zschornewitz since the early 1900. The study sites are located along a fly ash deposition gradient of 8, 16, 14, 18, and 25 km away from the main emission source in Bitterfeld (sites 1, 2, 3, 4, and 5, respectively). Samples of the organic horizons (Oi, Oe, and Oa) and mineral topsoil (0—10 cm) were taken in fall 1998 and analyzed for their ferromagnetic susceptibility and total ash content. Scanning electron microscopy (SEM) and energy dispersive X‐ray microanalysis (EDX) were performed on selected samples to differentiate between the pedogenic and atmospheric origin of the mineral components in the organic horizons. As a result of the long‐term deposition, ferromagnetic fly ash components are mainly accumulated in the Oe and Oa horizons of the forest soils studied. Ferromagnetic susceptibility was significantly higher (p ≤ 0.05) in the Oe horizon of sites 1 and 2 compared to sites 3, 4, and 5. Unusually high total ash contents for organic horizons of > 74 % were determined in the Oa at all sites. SEM revealed 3 distinct features of persistent fly ash deposits from coal‐fired power plants within the organic horizons that can be defined as ”︁stable glasses” with magnetic properties, aluminum‐silicate‐minerals, and slag fragments. SEM and EDX indicated that a great portion of the mineral particles found in the organic horizons of forests soils influenced by fly ash are from atmospheric sources. For detection of atmospheric lignite‐derived deposition into forest soils, the Oe and Oa horizons have to be considered as specific diagnostic horizons because they show indicative properties for such soils. 相似文献
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Epizootics of Streptococcus agalactiae infection in captive rays from Queensland,Australia
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![点击此处可从《Journal of fish diseases》网站下载免费的PDF全文](/ch/ext_images/free.gif)
R O Bowater M M Dennis D Blyde B Stone A C Barnes J Delamare‐Deboutteville M A Horton M White K Condon R Jones 《Journal of fish diseases》2018,41(2):223-232
The aim of this study was to describe two epizootics of high mortalities from infection with Streptococcus agalactiae, occurring in captive rays held in a marine display aquarium in south‐east Queensland, Australia, in 2009 and 2010. Five different species of rays were affected, including mangrove whiprays (Himantura granulata), estuary rays (Dasyatis fluviorum), eastern shovelnose rays (Aptychotrema rostrata), white‐spotted eagle rays (Aetobatus narinari) and blue‐spotted mask rays (Neotrygon kuhlii). This report describes the history of both epizootics including collection, quarantine and husbandry of rays, the disease epizootics, clinico‐pathological features of the disease, antimicrobial therapy, autogenous vaccine production, and laboratory studies including clinical and histopathology, bacteriology, PCR, molecular serotyping and sequencing of the bacterium S. agalactiae. 相似文献