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31.
To assess the relevance of spindle cell tumours in the canine gastrointestinal (GI) tract and to classify them, a retrospective study was carried out on haematoxylin and eosin-stained sections from formalin-fixed paraffin wax-embedded samples of 105 primary GI tumours. Seventeen out of 105 (16%) GI tumours were mesenchymal, 48% were epithelial and 36% were round cell tumours. Spindle cell tumours were stained by Masson trichrome, Orcein-Van Gieson and labelled immunohistochemically (vimentin, desmin, smooth muscle actin, protein S100, glial fibrillar acid protein, CD117 and MIB-1) and the histological grade, mitotic index, nuclear size and cellular density were also assessed. The 17 gastrointestinal mesenchymal tumours were classified as 10 leiomyomas (10/10 positive for desmin and smooth muscle actin; 6/10 positive for vimentin) 2 leiomyosarcomas (2/2 positive for desmin, smooth muscle actin and vimentin) and 5 gastrointestinal stromal tumours (GISTs) (5/5 positive for CD117 and vimentin; 3/5 positive for smooth muscle actin). Canine GISTs appeared as densely packed spindle cell tumours, with a diffuse, strong, cytoplasmic immunopositivity for c-kit protein (CD117). GISTs, defined as CD117-positive spindle cell or epithelioid or pleomorphic neoplasms that presumably derive from interstitial cells of Cajal, are reported in recent medical studies as the most common mesenchymal tumours of the GI tract. Our data suggest that GISTs represent a significant portion of canine GI spindle cell tumours, which can be definitely distinguished from leiomyosarcomas only by their expression of CD117. 相似文献
32.
Ramos-Vara JA Miller MA Ojeda JL Reid R Craft D Watson GL 《Ultrastructural pathology》2004,28(1):33-42
Renal cysts in the cortex of a juvenile Belgian Malinois dog with acute renal failure were studied by means of light, scanning and transmission electron microscopy, immunohistochemistry for intermediate filaments, and binding for wheat germ agglutinin (WGA), peanut agglutinin (PNA), and Maclura pomifera agglutinin (MPA) lectins to determine the morphological and histochemical features of the epithelial cells of these cysts. The cysts were renal corpuscles with expanded urinary space. Glomerular tufts were small with poorly developed capillary loops and increased mesangial matrix. Continuity with the proximal tubule was evident in some cystic glomeruli. Two cell types lined Bowman's capsule. One was squamous with a central cilium and microvilli. The other had morphological and histochemical features of immature podocytes (parietal podocytes). These cells were round and protruded into the urinary space; they had thick cytoplasmic projections that resembled foot processes of podocytes, microvilli, and filtration slits. The parietal podocytes expressed vimentin and cytokeratins and had affinity for WGA as do normal immature podocytes. These features suggest that the parietal podocytes are derived by metaplasia of the parietal cells. The basement membrane of Bowman's capsule was irregularly thickened and showed multifocal glycosylation changes with lectin histochemistry (WGA, PNA, MPA) in areas adjacent to the parietal podocytes. Histologic and ultrastructural findings in this dog are consistent with glomerulocystic kidney disease. This is the second report of canine glomerulocystic kidney disease. Features are similar to those of the human counterpart, but it is unclear whether genetic defects cause the disease in the dog. The presence of parietal podocytes in all cysts suggests that abnormal differentiation may play an important role in the pathogenesis of this type of polycystic kidney disease. 相似文献
33.
用甲酸消化法制取正常股动脉弹性纤维标本,冷冻干燥后进行扫描电镜观察。见到内弹性膜上有许多散分布的窗孔,中膜的弹性经组织呈复杂的网状,外膜的弹性组织以粗大的纵向分层排列的弹性纤维为主。 相似文献
34.
垂体后叶是重要的神经内分泌器官。对于垂体后叶的形态和功能研究是神经科学研究的热门课题。但以往对垂体后叶的研究大都是以大鼠、兔等低等动物为材料,而动物种间的差异很大。仅以大鼠等啮齿动物的资料为根据难以得出全面的解释。为此,作者对包括人、恒河猴在内的多种哺乳动物的垂体后叶内13种神经活性物质的分布进行了比较研究,得到了较为全面的资料。还发现2种新的神经纤维也存在于哺乳动物垂体后叶。本文用免疫组织化学方法证明了P物质免疫反应神经纤维不但存在于大鼠垂体后叶,也存在于人、猴、狗和猫的垂体后叶。比较五种动物垂体后叶P物质免疫反应神经纤维的密度,以狗垂体后叶为最高,人和大鼠次之,猴垂体有稀疏的分布,猫垂体后叶密度最低。在人和猴垂体后叶,P物质免疫反应神经纤维主要分布在垂体柄、神经叶的中央部和腹后部,其它部位仅见散在纤维。在狗垂体后叶背部和漏斗壁可见非常密集的纤维网,腹后部仅见中等密度P物质阳性纤维。猫漏斗壁的纤维束为中等密度,并沿漏斗隐窝壁直达漏斗隐窝底壁,其它部位仅见稀少的阳性纤维。大鼠垂体后叶周边部纤维密度高于中央区,吻侧端又稍多于尾侧端。 相似文献
35.
目的 :研究急性心肌缺血和梗死的多层螺旋CT(MSCT)心肌灌注特点 ,探索MSCT冠状动脉造影对冠状动脉阻断的显示情况。方法 :犬左冠状动脉前降支结扎前、后不同时期分别进行MSCT心肌灌注扫描 ,分析其特点 ,并与病理检查相对照 ;同时做MSCT冠状动脉造影观察冠状动脉阻断的情况。结果 :犬心肌正常灌注量为 ( 69.3±1 3 .9)ml·1 0 0g- 1·min- 1、达峰值时间 ( 1 2 .8± 2 .1 )sec。左冠状动脉前降支结扎 3 0min后MSCT心肌灌注表现为灌注量减低 ,时间密度曲线低平 ,延迟 1 0min扫描局部心肌密度无显著改变。结扎 4h后 ,局部心肌呈明显延迟增强。MSCT冠状动脉造影显示冠状动脉前降支中断。结论 :MSCT心肌灌注结合冠状动脉造影可以判断心肌缺血和梗死 ,同时显示冠状动脉的阻塞状况 相似文献
36.
Nils Koppang 《American journal of medical genetics. Part A》1992,42(4):599-604
The etiology of the juvenile type of the human ceroid-lipofuscinosis (JCL) is unknown, in spite of the fact that the first report of this disease was given more than 160 years ago. The necessity of good animal models for scientific progress in chronic metabolic diseases in humans is obvious. The inbred strain of English setter with ceroid-lipofuscinosis (CCL) seems to be a perfect model for human JCL. Dogs with CCL and organs for research purposes are available from Dr. Koppang's experimental kennel in Norway. 相似文献
37.
Summary The flux rates of plasma glucose and alanine were studied isotopically (6-3H-glucose and U-14C-alanine simultaneously) in resting chronically diabetic dogs during short-term treatment with an artificial B cell where the insulin was infused into a peripheral vein. Despite perfect blood glucose control and normal glucose flux rates, the concentration and rates of appearance and disappearance of alanine were significantly elevated in the diabetic animals before, during and after an exogenous glucose load. The incorporation of the carbon moiety of alanine into circulating glucose was also increased, but diminished to a near-normal extent when exogenous glucose was given. The plasma clearance rates for alanine in the diabetic dogs were normal throughout the study. It is concluded that normal blood glucose control in diabetes does not necessarily mean normalization of the entire metabolic network. On the basis of peripheral hyperinsulinaemia alanine formation from glucose and branched chain amino acids is elevated in muscle. This may explain increased flux of alanine despite normal blood glucose control. 相似文献
38.
观察却老壮骨片(壮骨片)连续给药后对家犬可能产生的毒性反应及性质。用壮骨片0.167、0.334、0.668mg/kg/d和甲基炔诺酮(0.154mg/kg/d)及尼尔雌醇(0.514mg/kg/d)给家犬连续口服180d,观察用药期间毒性反应及停药21天期间恢复情况。结果表明在用药150天后,壮骨片高剂量组和甲基炔诺酮高剂量组,动物体重增长虽略有减慢,但与对照组比较无显著性差异(P>0.05);其他各剂量组各功能检查未见明显变化。壮骨片在相当成人常用量74.2倍的大剂量下对家犬无毒性。 相似文献
39.
目的:观察地塞米松对犬视网膜超微结构的影响。方法:取犬4只,右眼玻璃体和房水内注射盐水(为盐水组),左眼玻璃体和房水内注射地塞米松(为激素组),24h后处死,电镜观察视网膜超微结构有无改变,并与对照组进行比较。结果:盐水组和激素组与对照组比较视网膜超微结构无改变。结论:地塞米松对犬视网膜超微结构无影响。,Objective:To observe the influence of dexamethasone on dog's retina ul-trastructure. Methods:We injected normal saline into the vitreous body and aqueous humor ofthe right eyes while injecting dexamethasone into the left eyes in four dogs. After 24 hours, wekilled the dogs to observe ff their retina ultrastructure had altered, and compared with the re-sults of the control group. Results :In comparision with the control group,there was any changein retina ultrastructure in neither the normal saline group nor the hormone group. Conclusion:Dexamethasone has no influence on the retina uitrastructure of dogs. 相似文献
40.
异烟肼预防食管良性狭窄的实验与应用研究 总被引:6,自引:0,他引:6
探讨异烟肼预防食管良性狭窄的作用。方法分动物实验及临床应用两部分,动物实验采用家犬20只,分为3组,按Davis动物模型致伤为深Ⅱ度食管腐蚀伤,采用异烟治疗,临床应用系对26例食管食性狭窄患者采取扩张术后异烟治疗以预防食管再狭窄。结论异烟能够防治食管良性狭窄,在临床工作中有一定的推广价值。 相似文献