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11.
Four cases of ulceration and stricture of the right dorsal colon were encountered. Ulceration of the right dorsal colon is generally associated with nonsteroidal anti-inflammatory drug (NSAID) toxicosis but there are few reports of stricture following ulceration. All four horses had recent phenylbutazone use: three had been given doses well in excess of the recommended dose and in one the dose was marginally above those recommended but was combined with administration of other NSAIDs. All four horses presented with intermittent low-grade colic, weight loss and ventral oedema. Diarrhoea was also seen in three of them. All had hypoproteinaemia due to severe hypoalbuminaemia, and hyperfibrinogenaemia. Hypoalbuminaemia was less severe in one horse and this horse was successfully managed medically. Two cases were definitively diagnosed at exploratory celiotomy and two at necropsy. Exploratory celiotomy was performed in two horses: one was euthanased at surgery and one was managed successfully with medical treatment and remained normal 1 year after surgery. Medical management included feeding of a low-roughage pelleted ration, corn oil, psyllium mucilloid, and discontinuation of NSAID administration.  相似文献   
12.
The purpose of this study was to establish the normal percutaneous ultrasonographic appearance of anatomic structures within the equine sacroiliac region. Percutaneous ultrasonography was performed in a cranial-to-caudal direction in 10 normal adult live horses. The following structures were examined in detail: supraspinous ligament, lumbar and sacral spinous processes, thoracolumbar fascia and its caudal extension, tubera sacralia, ilial wings, dorsal and lateral portions of the dorsal sacroiliac ligaments, lateral part of the sacrum, and the lateral sacral crest. After ultrasonography, all animals were euthanized and detailed dissection of the lumbosacropelvic region was performed in six horses. Four lumbosacropelvic specimens were frozen and sectioned transversely for evaluation of cross-sectional anatomy. Gross anatomic findings were correlated with ante-mortem ultrasonographic images. On percutaneous ultrasonography, all horses had tubera sacralia with a mild-to-moderate roughened surface with occasional irregular hyperechoic mineralizations located within the apophyseal cartilage of younger horses. At the level of the tuber sacrale the caudal extension of the thoracolumbar fascia joined the dorsal portion of the dorsal sacroiliac ligament and assumed two different configurations relative to the dorsal portion of the dorsal sacroiliac ligament, with the predominant configuration of the thoracolumbar fascia located medial to the dorsal portion of the dorsal sacroiliac ligament. The less frequently encountered configuration had the thoracolumbar fascia positioned dorsal to the dorsal portion of the dorsal sacroiliac ligament. Caudal to the tuber sacrale the dorsal portion of the dorsal sacroiliac ligament and thoracolumbar fascia consolidated to form a single, fused structure with a common insertion on the sacral spinous processes. A large variability in linear fiber pattern, echogenicity (small focal hypoechoic areas), ligament height, and cross-sectional measurements was identified in the fused dorsal portion of the dorsal sacroiliac ligament and thoracolumbar fascia of normal horses. Diagnosing mild-to-moderate desmitis of the fused dorsal portion of the dorsal sacroiliac ligament and thoracolumbar fascia based solely on ultrasonography may therefore be difficult. To correlate ultrasonography with histology, samples of a fused dorsal portion of the dorsal sacroiliac ligament and thoracolumbar fascia with bilateral hypoechoic lesions were submitted for histology and revealed diffuse mild-to-moderate loss of fiber density, multifocal fibrocyte degeneration, and cartilagenous metaplasia with multifocal, mild myofiber mineralization, which was compatible with age-related changes. As controls, sections of ultrasonographically normal fused dorsal portion of the dorsal sacroiliac ligament and thoracolumbar fascia from three horses demonstrated similar but milder histologic findings, which were considered normal.  相似文献   
13.
为探讨胚胎晚期暴露细菌脂多糖(LPS)的中年CD-1小鼠背侧海马的类泛素化蛋白(SUMO-3)含量有无年龄相关性改变。采用免疫组织化学技术检测LPS暴露组和对照组CD-1小鼠背侧海马DG区、CA1区和CA3区各亚层的SUMO-3表达。结果表明,两组间各区各亚层的SUMO-3含量无明显差异。  相似文献   
14.
为研究鲤疱疹病毒Ⅱ型(Cy HV-2)体外感染复制特征以及异育银鲫抗病毒免疫应答反应。本实验采用组织块培养法建立了异育银鲫背鳍细胞的原代培养体系。结果显示,在10 d左右可观察到组织块迁移分离出新的单层细胞,3周左右细胞可覆盖底部面积为25cm2培养瓶的底部;经Cy HV-2悬液感染离体培养的原代细胞,3 d后病毒滴度增殖至106拷贝/m L;在病毒感染6 d后出现典型的细胞病变效应;Cy HV-2感染原代细胞后,分析前期通过鱼体水平实验鉴定出的与该病毒感染相关的免疫基因:PNP5a、MPO、MHCⅠ、LYZ-C、IL-11、ITLN、PNP5a和DUSP,Real-time Rt-PCR结果显示大部分基因在细胞水平均有显著性的上调,与鱼体水平实验结果一致。本研究建立了原代培养的异育银鲫背鳍细胞,用于构建体外感染Cy HV-2病毒的细胞模型,为深入研究Cy HV-2的感染复制规律及其与宿主的相互作用关系,以及细胞水平筛选抗病毒药物实验奠定了基础。  相似文献   
15.
  1. Mediterranean fin whales aggregating in the Pelagos Sanctuary in summer to feed are exposed to vessel collision risk, particularly from high-speed ferries.
  2. This study developed models to predict summer fin whale distribution using a generalized additive model (GAM) and MaxEnt, with the aim of providing a tool to identify potential high whale–ferry collision risk areas along ferry routes within the Pelagos Sanctuary during summertime.
  3. Models were trained using sightings data collected in the summer months of 2009–2018 on board ferries crossing the central area of the Pelagos Sanctuary. Environmental predictors were bathymetry and mean sea surface chlorophyll concentration of the annual spring bloom period.
  4. The predictive ability of GAM and MaxEnt was assessed using existing knowledge of summer fin whale distribution in the region. GAM (deviance explained = 20.2%) predictions matched documented distributions more closely than that of MaxEnt, with highest predicted fin whale occurrence in deep offshore waters (>2000 m) encompassing the central north-western and western regions, and in the south-eastern region, consistent with known fin whale habitats within the Pelagos Sanctuary. Inter-annual variability was evident, influencing collision risk areas.
  5. Collision risk was estimated as a function of the overlap between the predicted probability of fin whale occurrence and ferry density estimated from Automated Identification System data. Ferry routes that cross the northern and eastern regions of the Pelagos Sanctuary presented relatively higher collision risk.
  6. Areas with changes in risk intensity between the years were temporally and spatially dynamic: some appeared intermittently throughout the study period while others persisted over consecutive years or recurred in different years.
  7. Due to the vastness of the Pelagos Sanctuary, vessel speed reduction maybe a more practical measure to manage collision risk than re-routing shipping lanes. A combination of Seasonal Management Areas and Dynamic Management Areas approaches could be adopted for high-risk areas.
  相似文献   
16.
本文从草鱼尾鳍组织建立了一个二倍体细胞系GCCF-2。该细胞系用TC-199培养液加15%小牛血清培养。细胞生长旺盛,最高分裂指数达30.04‰。现已在体外培养近92个月。细胞在28℃生长良好。染色体检查表明,GCCF-2为二倍体细胞系。初步估计其细胞周期为21—33小时。GCCF-2对草鱼呼肠弧病毒(GCRV)敏感,并在细胞中发现病毒颗粒。  相似文献   
17.
The contribution of the thyroid hormone to the metamorphosis of the coral trout Plectropomus leopardus was examined. Juveniles, aged 35 days, were exposed to thyroxine (T4, 0.1 p.p.m) and thiourea (TU; inhibitor of thyroid hormone synthesis, 30 p.p.m) for 13 days. All the fish in the T4-treated group had completed metamorphosis (second metamorphosis, pigmentation and resorption of fin spines) within three days after the beginning of the experiment (day 3), whereas it took 13 days for this to occur in the control fish. Moreover, the fish in the TU group had not completed metamorphosis even by day 13. Settling behavior was significantly stimulated by T4 treatment, as was the resorption of the dorsal and pelvic fin spines, the reduction of serration on the spines, and the transition of body color into an opaque reddish hue. Fish in the TU group had longer dorsal and pelvic spines, retarded pigmentation and an abnormal black coloration. These results suggest that thyroid hormone accelerates most changes during the second metamorphosis in the coral trout.  相似文献   
18.
在光镜下观察北京鸭脑的连续切片。并将 HRP 注入食管、胃、心脏和脊髓,逆向追踪迷走神经背核传出神经元在核内的定位。北京鸭迷走神经背核位于延髓呈纵向细胞柱,可明显地分为背侧部和腹侧部。腹侧部含淡染小细胞,多为梭形,细胞直径18~20 μm。背侧部内含中小型细胞,混合排列,直径20~35 μm;在闩前的后段还出现大细胞,直径35~40 μm。在二部的外侧有一小部为外侧部。本文提出按部位划分亚核的原则以利应用。共分为尾侧亚核、吻侧亚核、闩前背侧后核、闩前腹侧后核、闩前外侧后核、闩前背侧前核、闩前腹侧前核、闩前外侧前核共8个亚核。用 HRP 法追踪投射到食管各段、腺胃和肌胃薄肌与厚肌、心脏以及脊髓的神经元,肯定了北京鸭迷走神经背核投射至以上各外周器官的神经元在核内有一定的定位区域。  相似文献   
19.
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   
20.
OBJECTIVE: To describe and evaluate subtotal ostectomy of dorsal spinous processes (DSP) performed in standing horses. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Nine adult horses. METHODS: The diseased portions of the DSP were removed with the horses standing and sedated after infiltrating a local anesthetic agent around the affected DSP. Medical records of affected horses were reviewed to determine history, findings of physical and radiographic examination, surgical technique, postoperative complications, and outcome. RESULTS: Five horses had subtotal ostectomy of DSP because of osteomyelitis, and 4 because of impingement and/or fracture of DSP. Affected portions of DSP were removed safely and effectively, with no apparent discomfort to the horses; hemorrhage was minimal. CONCLUSIONS: Subtotal ostectomy of DSP can be performed safely in standing, conscious horses and the risks associated with general anesthesia are eliminated. Hemorrhage is minimal compared to that which occurs when the procedure is performed with horses anesthetized and in lateral recumbency. CLINICAL RELEVANCE: Access and visibility are better when subtotal ostectomy of the DSP is performed with the horse standing rather than anesthetized and in lateral recumbency. Performing subtotal ostectomy of diseased DSP with the horse standing avoids the expense and risks of general anesthesia.  相似文献   
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