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1.
本文应用光镜和透射电镜对山羊胚胎大动脉壁的发生发育过程进行了系统观察。结果表明:血管发生初期仅由一层内皮细胞构成。随着胚胎的发育,除毛细血管外,其它血管壁形成分层结构,形成内膜、中膜、外膜;胚胎大动脉内皮细胞胞质内存在着丰富的粗面内质网和游离核糖体,代谢是很活跃的;大动脉管壁的内弹性膜形成较晚,先产生小片段,然后呈连续带状;大动脉内膜和中膜内不含典型的成纤维细胞,在中膜内存在一种能产生胶原纤维的细胞,其结构类似于平滑肌细胞。  相似文献   

2.
血脑屏障是隔离外周体循环和中枢神经系统的屏障结构.它可以选择性允许血液中的一些物质通过脑微血管内皮细胞进入大脑中.除了脑微血管内皮细胞之外,血脑屏障的组成主要还有星型胶质细胞、周细胞、神经元和细胞外基质.本试验通过原代培养猪脑微血管内皮细胞和星型胶质细胞,以Transwell细胞板为载体构建猪体外血脑屏障的共培养模型.经过4h渗漏试验和TEER电阻的测定试验显示所构建的猪体外血脑屏障的模型具备了血脑屏障基本的生物学特性,可以用于猪血脑屏障相关疾病尤其是人兽共患性疾病致病机制的研究.  相似文献   

3.
运用组织学研究方法,比较成年牦牛和平原黄牛肺动脉的结构组织和形态学差异,初步探讨成年牦牛肺动脉对低氧的适应性结构。结果表明,成年牦牛肺动脉管壁直径小于200μm时,仍含有较多的弹性纤维,在直径为50μm的肺动脉管壁中,仍存在1~2层完整的平滑肌。而成年黄牛其肺动脉管壁直径小于100μm时,其管壁中含有的弹性纤维比成年牦牛直径大小相似的肺动脉管壁中的弹性纤维少,平滑肌消失或呈月牙状分布,但外弹性膜完整。成年平原黄牛肺动脉血管中膜的MT值随管径的增加逐渐减小,成年牦牛肺动脉血管中膜MT值在管径为100~200μm时最大,然后逐渐减小。至肺门部时,其肺动脉血管中膜MT值接近相等,且差异不显著。因此,成年牦牛肺动脉含有的弹性纤维比成年平原黄牛多,该结构特点是成年牦牛在高原低氧环境下维持肺动脉较好射血功能的结构基础,此外,与成年黄牛比较可见,成年牦牛50μm直径的肺微动脉仍具有完整的平滑肌层,这一现象可能是牦牛在高原低氧环境下维持较好血流的结构基础。  相似文献   

4.
1猪应激的临床表现形式1.1急性死亡这是应激表现最为严重的形式,个别应激敏感猪在受到抓捕惊吓或注射时突然死亡,有的公猪在配种时,由于过度的兴奋而死亡,有些猪在车船运输时突然死亡。1.2应激综合征心脏变化主要发生于3~4月龄的猪。常常突然死亡,病因不明。最典型的病变是心脏广泛出血,外观如桑葚。由于在心脏和其他组织中都发现有过碘酸阳性物质沉着于毛细血管和毛细血管前动脉的内膜下和血管内,因而也称营养性微血管病。  相似文献   

5.
近年来,随着对微血管内皮细胞电生理特性的深入研究,发现膜上存在有多种离子通道。这些离子通道可通过直接或间接的方式影响钙信号的传导,从而调节微血管内皮细胞的分泌、增生及基因表达,参与多种生理和病理过程。因此,微血管内皮细胞膜上的离子通道可能是多种病理过程的重要环节和药物调节细胞功能的潜在靶点。对微血管内皮细胞膜上的离子通道功能的研究,不但有助于揭示多种疾病的病理机制,而且有助于新型药物的开发。文章综述了近年来在微血管内皮细胞膜上的离子通道种类、特性及其功能研究方面取得的进展,以期为进一步的相关研究提供资料。  相似文献   

6.
比较观察和测量了高原藏羊和平原小尾寒羊的肺组织结构,并就藏羊肺组织形态测量指标与高原低氧的关系进行了初步探讨。结果表明,藏羊肺组织在肺泡大小、单位面积肺泡数和细小血管数、肺泡隔的厚度、肺泡隔内弹性纤维含量和毛细血管数量、终末细支气管的管径及细小动脉管壁中弹性纤维和平滑肌的含量等方面与小尾寒羊的肺组织相应值比较,表现有一定的差异和特点,这些差异和特点正是藏羊肺组织适应高原低氧的形态学特点。  相似文献   

7.
采用石蜡切片及微血管铸型技术,观察了成年大鼠睾丸微血管的分布与构筑形式.光镜下每个生精小管与六个生精小管相临,微血管则明显得排列在相临生精小管形成的六角形的角缘处.扫描电镜下观察到睾丸表面的微动脉吻合为网格状;这种形式为睾丸表面的生精小管提供了丰富的营养和必要的激素水平;睾丸动脉主支发出走行迂曲的睾丸小动脉,进入睾丸小隔后,再发出管间微动脉,并与管间微动脉相互连接为绳梯状的毛细血管网.睾丸实质内绳梯状的毛细血管网,使每个生精小管都能得到充分的营养和激素供应;睾丸内的动脉迂曲走行,对于维持睾丸低于体内3~5℃的适宜温度,使精子正常产生,具有重要意义.  相似文献   

8.
取成年鸡身体不同部位的正常皮肤(胸裸区皮肤、肩胛裸区皮肤、耳后裸区皮肤、胸羽区皮肤、小腿羽区皮肤和颈羽区皮肤),HE染色和地衣红染色,光镜下观察研究鸡不同部位正常皮肤的结构。鸡正常皮肤表皮很薄,细胞层数少,其中棘层细胞很少,棘细胞散在分布于基底层和移行层之间;胸部羽区、胸部裸区和耳后裸区的真皮浅层中含有较多的纤维细胞与毛细血管;羽区的致密层未见到平滑肌,裸区和羽区的疏松层内均见到平滑肌;真皮深层的疏松层发达,较致密层厚;颈部羽区未观察到弹性纤维层。  相似文献   

9.
表皮生长因子及其受体在山羊胎儿皮肤发育中的表达特征   总被引:1,自引:0,他引:1  
运用组织学和免疫组化方法对山羊皮肤发育的组织学特点、山羊皮肤发育过程中表皮生长因子(EGF)及其受体(EGFR)的分布及变化规律进行了系统研究.结果显示:(1)表皮结构形成于胎儿发育的6周龄左右,开始为单层上皮,而后逐渐增殖为复层、厚度不断增加,15周龄后逐渐变薄;真皮层在10周龄时形成,11周龄后陆续有皮肤衍生结构从中发育形成.随着胚胎的继续发育,皮肤各部分结构的发育渐趋完善.(2)在胎儿发育的第6周就出现EGF与EGFR的较弱表达,以后随着胎龄的增加,EGF与EGFR表达量逐渐增加.从表达分布看,在胎儿发育的11周前,EGF阳性反应主要定位于表皮基底层细胞、毛囊上皮细胞和真皮成纤维细胞等的胞质内,EGFR则主要位于相应细胞的膜上;11-16周,EGF和EGFR表达量逐渐增高,分布范围从表皮的基底层细胞、棘细胞、毛囊上皮细胞和成纤维细胞扩展到血管内皮细胞、汗腺上皮细胞和竖毛肌,EGF主要定位于这些细胞的胞质,EG-FR则主要分布于细胞膜;17周至出生,随着表皮的明显变薄,EGF及EGFR主要分布于表皮基底层细胞和毛囊上皮细胞,阳性反应继续增强.皮肤发育期间,EGF及EGFR的表达量总体呈增长趋势,只是EGFR的表达相对滞后,两者的表达曲线一致、相关性极显著.表明EGF及EGFR在皮肤及其衍生结构的发育中发挥着重要作用.  相似文献   

10.
《中国兽医学报》2019,(5):956-961
本试验旨在探究大肠杆菌热敏肠毒素处理(heat labile enterotoxin,LT)后,猪小肠黏膜微血管内皮细胞活力及细胞因子ET-1、IL-1β水平的变化。首先采用D-半乳糖凝胶树脂层析法提取猪E coli LT,利用SDS-PAGE验证蛋白纯度,并用Vero细胞检验提取物的生物学活性,最后采用CCK-8法检测LT对猪小肠黏膜微血管内皮细胞活力的剂量时间效应,ELISA法检测细胞培养上清中ET-1、IL-1β水平的变化。结果表明:所提蛋白为AB_5结构的LT,且具有良好的生物学活性;0.01 mg/L的提取蛋白作用3 h后便可显著降低小肠黏膜微血管内皮细胞的活性(P0.05);作用细胞6 h后,0.01,0.1和10 mg/L LT组细胞培养上清中ET-1的含量显著升高(P0.05),0.01和1 mg/LLT组IL-1β的含量显著升高(P0.05)。结果表明,E coli LT可以显著改变猪小肠黏膜微血管内皮细胞的活力及细胞因子的表达。  相似文献   

11.
The objective of this work was to study the histological structure of the dog's coronary artery by light and transmission electron microscope (TEM). The coronary artery consisted of three tunics: tunica intima, tunica media and tunica adventitia. The tunica intima consisted of endothelium rested directly on internal elastic lamina without the subendothelial connective tissue layer. The tunica media were composed of smooth muscle fibres interspersed with few elastic and collagen fibres. The tunica adventitia consisted of collagen and elastic fibres intermingled with fibroblast cells; it had vasa vasorum and nervi vasorum. Some histomorphometric measurements were performed and compared statistically. The ultrastructural study showed that the endothelial cells were communicated through complex junctions and characterised by filiform cytoplasmic processes passed through the opening of the underlying internal elastic membrane. The smooth muscle fibres of tunica media communicated with each other through cytoplasmic processes. The tunica adventitia showed minute non-myelinated nerve. This work revealed that the dog's coronary arteries are typical muscular arteries, which show little structural variations from that of other mammals.  相似文献   

12.
For a first time the endothelin (ET)-positive mast cells were examined in the wall of kidney renal artery and vein. The specimen's were collected from six 8-month-old Danmark Landrace pigs, immediately after slaughtering. Mast cells immunopositive to ET granules were observed in the wall of both artery and vein. In the renal artery, they were found mostly between the media and the adventitia. Some mast cells were found in the media, next to smooth muscle cells. Relatively few mast cells were found in the intima and between intima and tunica media. In the renal vein a smaller number of mast cells were observed. They showed similar localization as in the renal artery. Immunopositive mast cells were established also close to endothelial cells - mostly between internal elastic membrane and basal membrane of the endothelium. In conclusion, on the basis of obtained results, presumptions for active participation of ET (most probably mainly ET-1) in the motility of the vessels' smooth muscle and for stimulation of nitric oxide release from the intimal endothelial cells were made.  相似文献   

13.
不同品种和年龄牛胆囊的比较组织学研究   总被引:1,自引:0,他引:1  
通过对八例健康黄牛和健康小牛胆囊的比较组织学观察,我们发现,牛胆囊中以颈部粘膜皱臂明显,体部渐平坦,底部最少。粘膜上皮为单层柱状上皮,内有少量杯关细胞,大部分胆囊可见有淋巴滤泡,但是在血管周围未见淋巴和异染细胞的浸润,证明滤泡的形成与胆囊感洒无关。这种淋巴滤泡在黄牛胆囊中较多,水牛胆囊仅见一例。在黄牛和水牛胆囊中,均有腺体存在,黄牛的腺体明显多于水牛。腺体分为浆液腺、粘液腺和混合腺。老龄牛胆囊中腺  相似文献   

14.
Anatomy of the sinus node was studied in six camel hearts (Camelus dromedarius) with serial histologic sectioning. The sinus node in this species of animal was located 0.5 mm beneath the epicardium, near the junction between the cranial vena cava and the right atrium at the sulcus terminalis. Its shape was elongated, bent oblong with 28.25 mm length, 5.75 mm width and 5.38 mm thickness. The maximum section area was 101.66 mm2. The central artery of the node originated from the circumflexus branch of the left coronary artery and, throughout its length in the substance of the sinus node, had an internai elastic membrane. Histologically, the sinus node of this animal contained a central artery and a framework of collagen fibres, which were distributed around the central artery. The nodal cells were irregularly organized around the central artery and two types, i.e.‘p’ cells and transitional cells were present. The ‘p’ cells had a perinuclear clear zone but the transitional cells contained more myofibrils. The intercalated dises were not present. At the periphery of the sinus node there were many nerve fibres and a ganglion. The purkinje fibres were present within atrial myocardium, as well as within ventricular myocardium. The glycogen content of the sinus nodal cells was higher than that of the atrial myocardial cells.  相似文献   

15.
应用免疫组织化学技术研究降钙素基因相关肽在鸭腔上囊胚胎及胚后发育过程中的表达特征.结果显示,降钙素基因相关肽强阳性细胞出现于20 d胚龄至胚后14周龄的滤泡间上皮,20 d胚龄至胚后17周龄的小结相关上皮,新生雏至胚后14周龄的滤泡皮质,24 d胚龄至胚后14周龄的滤泡髓质,20 d胚龄至胚后14周龄的肌层和小动脉平滑肌.结果说明,降钙素基因相关肽表达于鸭腔上囊的不同部位及不同发育阶段;在腔上囊退化期,降钙素基因相关肽的表达表现出明显的变化特征,这可能是导致腔上囊退化的原因之一;滤泡间上皮与小结相关上皮在神经肽表达方面存在差异.  相似文献   

16.
The purpose of this study was to gain knowledge about the micromorphology of the porcine common carotid artery (CCA) during the period of growth over the bodyweight range of 10–40 kg. CCA samples from German landrace pigs (DL) aged either 2 or 3 months (DL-2 and DL-3) were compared with samples from Göttingen minipigs (GM) aged either 18 or 40 months (GM-18 and GM-40) using transmitted light (phase-contrast mode) and transmission electron microscopy. The GM-18, GM-40 and the DL-3 groups had typical muscular artery histological characteristics. Contrasting to this, the 2-month-old DL pigs had a transitional artery type being characterized by a significantly higher proportion of elastic fibres and a significantly lower number of smooth muscle cells than did the 1 month older DL-3. During the period of maturation, the tunica media of the CCA in GM animals thickened by 1.3× and in DL animals by 2.5× resulting in an overall increased vessel wall thickness. The cumulated thickness of the tunica interna (endothelium, stratum subendotheliale and internal elastic lamina) and the tunica media (including the external elastic lamina) of DL-3 and GM-40 pigs were similar to each other and comparable to that of humans. With an increasing vessel wall thickness, the luminal diameter decreased in GM by 19% and in DL by 11%. Additionally, in the older age groups, GM-40 and DL-3, the internal elastic lamina principally was continuous, but there were also interrupted large segments of elastic lamina separated by gaps. In addition, the principal internal elastic lamina was duplicated in several places.  相似文献   

17.
In the present study, we compared the utility of immunohistochemistry with serological and histological results for the characterization of Mycobacterium avium ssp. paratuberculosis (M. paratuberculosis) in tissues of affected red deer. Bacterial isolation was considered the standard reference. Samples were taken from seven clinically affected animals with typical macroscopic lesions. The enzyme linked immunosorbent assay (ELISA) and the gel diffusion tests (GD) were used for serological determinations. Samples from intestine and mesenteric lymph nodes were processed for bacterial isolation and histology. M. paratuberculosis was isolated from all the animals. Histologically, lymph nodes displayed necrosis and mineralization at the cortical and medullar areas. Ziehl-Neelsen stained bacteria were numerous inside macrophages and Langhans-type giant cells. Giant and epithelioid cells and lymphocytes were prominent at the ileal mucous membrane. The immunostaining of M. paratuberculosis was very clear inside epithelioid and giant cells. Image analysis was carried out to determine the immunostained area. There was total agreement among the methods employed. Immunohistochemistry can be very useful when the microorganism cannot be recovered from tissues or faeces.  相似文献   

18.
The purpose of this study was to determine the morphology of the rabbit carotid body and its artery at the light microscopy level. The carotid body was situated between the internal and external carotid arteries after the bifurcation point of the common carotid artery. The carotid body was usually found to be a single, ovoid tissue mass but, in some cases it consisted of two or three parts. More carotid bodies were supplied by a single carotid body artery (glomic artery) which arose from the common carotid artery or the internal or external carotid arteries near the bifurcation point of the common carotid artery. In only one case were there two arteries which arose from opposite sides of the external carotid artery at its origin. There was a distinguishable sinus (glomic sinus) at the origin of the glomic artery. This artery had a thin wall with elastic laminae in the sinus area which become thinner distal to the sinus.  相似文献   

19.
The unexpected demise of a 12-year-old male neutered English bulldog solicited a gross examination, which revealed a blood-filled space occurring in the proximal left subclavian artery (LSA). It originated about 1 cm from the branching point of the vessel and progressively dilated for 3 cm distal to this origin. Histopathological investigation showed that the tunica media of the LSA was more than 50% split, with the blood-filled space dissecting through the arterial wall. In the tunica media of the LSA, severe multifocal fragmentation and/or loss of the elastic fibers was observed. The retained disorganized elastic fibers were separated and disoriented due to accumulations of acid mucopolysaccharide. Marked, diffuse medial, and adventitial fibrous tissue deposition was also identified. The cause of death was attributed to acute hemorrhagic and necrotizing pancreatitis with pulmonary edema, suggesting that LSA dissection was an incidental finding. Subclavian artery dissection is extremely rare in humans, where the involvement of the LSA in cases of aortic dissection both with or without Marfan syndrome has been reported. Aortic and pulmonary artery dissection in bovines and aortic aneurysm and dissection in dogs have been reported to be associated with Marfan and Marfan-like syndromes, respectively. Histopathological findings suggestive of underlying connective tissue abnormalities resembling Marfan-like syndrome (i.e., the appearance of the elastic tissue and the degenerative changes of the tunica media) were detected in the first case of LSA dissection in dogs and veterinary medicine, herein described.  相似文献   

20.
Dirofilaria immitis was found in the right ventricle, pulmonary artery, and lungs of 2 red foxes (Vulpes fulva) in Connecticut. The most significant lesions occurred in the pulmonary artery and consisted of focal atheromatous-like intimal plaques, diffuse subintimal accumulations of inflammatory cells, and marked villose endarteritis in the elastic portion of the pulmonary artery. Medial hyperplasia of the muscular branches, along with periarteritis, was found in 1 fox. These 2 cases may be a further indication of the increased incidence of this disease in Carnivora in the State of Connecticut.  相似文献   

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