首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 265 毫秒
1.
将鸭肿头出血症病毒(DSHDV)强毒株以不同途径接种10日龄鸭胚,研究了病毒在鸭胚中的繁殖规律,并用透射电镜观察了感染鸭胚各组织器官的超微结构变化,同时用DSHDV人工感染不同日龄雏鸭,比较了不同感染途径对雏鸭的致病性和对不同日龄雏鸭的致病性。结果显示,尿囊腔和卵黄囊2种途径均能使病毒在鸭胚上繁殖并传代,对鸭胚的半数致死量分别为10^-7.24/0.2mL和10^-6.4/0.2mL。病毒感染鸭胚后,电镜下可观察到肝和尿囊膜中的病毒粒子,病毒粒子呈球形或椭圆形,大小为60~80nm,无囊膜;病毒在细胞浆内复制,可形成特征性包涵体;病毒侵害的主要靶器官为尿囊膜与肝,细胞器的变化主要表现为粗面内质网扩张以及线粒体肿胀和嵴断裂、消失。病毒经肌肉注射、口服和滴鼻均能使28日龄鸭感染发病,致死率分别为86%、89%和97%。研究表明,DSHDV能很好地在鸭胚上生长并致鸭胚各组织器官超微结构发生变化,不同感染途径均能使雏鸭感染发病且致病性强。  相似文献   

2.
采用超薄切片和透射电子显微镜技术对鸭病毒性肠炎病毒CH强毒株(DEV-CHv)在鸭胚成纤维细胞(DEF)中的形态发生学进行了研究。结果表明,DEV-CHv吸附到DEF细胞上以后通过囊膜和细胞膜间发生融合的方式侵入宿主细胞;病毒在细胞核内完成病毒核酸的生成、核酸与衣壳的装配;病毒核衣壳通过核膜-内质网膜系统从细胞核转运到内质网池中并在内质网池中得到皮层结构;获得了皮层的DEV-CHv核衣壳通过出芽方式释放到细胞空泡内得到囊膜结构后成为成熟病毒;细胞空泡内的成熟DEV-CHv可通过细胞的胞吐作用被释放到细胞外,或在空泡破裂时被释放到细胞外。  相似文献   

3.
用从自然病例中分离鉴定的鸭瘟病毒-乐山株(DPV-LS株)人工感染四川麻鸭,成功复制出鸭瘟(DP),并对其病理组织学和宿主细胞超微结构变化及病毒的形态结构进行观察.试验组鸭出现高热、神萎、不食、腹泻,剖解见食道、小肠、泄殖腔及各实质器官出血;组织学变化表现为各脏器出血、组织细胞变性、坏死,血管内皮受损,纤维素样坏死.超微病理学变化:肝细胞、网状细胞、上皮细胞、心肌细胞等的胞浆内粗面内质网严重扩张、核糖体脱落、空泡化,线粒体肿胀、嵴紊乱或断裂甚至形成空洞;胞核染色质浓集于核的周围,核形不整、核膜扩张或消失,核仁消失.同时在心、肝、脾、食道、泄殖腔、小肠的细胞内观察到了处于不同发育阶段的病毒粒子,成熟病毒粒子具有疱疹病毒的典型形态结构,呈球形或近似球形,直径150~200 nm,位于核膜间隙及胞浆内.  相似文献   

4.
40只2日龄四川白鹅口服感染雏鹅新型病毒性肠炎病毒,在不同阶段解剖发病和死亡雏鹅,电镜观察组织器官的病理变化发展规律.接种后第2天,十二指肠绒毛顶部上皮细胞发生坏死、脱落.随着感染时间延长,上皮细胞的坏死、脱落迅速向绒毛基部发展,并伴随固有膜炎性细胞浸润和坏死,病变向着空肠段发展.进一步发展为纤维素性坏死性肠炎,于小肠中后段形成假膜包裹肠内容物的栓塞物或直接由纤维素性渗出物与坏死肠粘膜混合凝固形成栓塞物阻塞肠腔,使外观膨大.肺充血和出血.肾充血、出血及肾小管上皮细胞变性.部分病例肝颗粒变性、脂肪变性.后期部分病例气管、腺胃上皮细胞脱落.早期部分病例心充血和出血.食道、胰腺及脑正常.电镜下可观察到小肠上皮细胞核畸形、固缩、核仁消失、核膜模糊和胞核崩解;胞浆严重空化,形成含有很多病毒粒子的"封入体”;粗面内质网扩张呈囊状,其上的核蛋白体严重脱落;线粒体外膜破裂或嵴断裂及空化,部分受到损害的线粒体充满大量的病毒粒子;形成肠道栓子的外层假膜有大量的病毒粒子、细菌以及坏死的肠上皮细胞.肝脏细胞粗面内质网严重扩张及部分线粒体肿胀、脊断裂;而心肌细胞粗面内质网的轻度扩张及胞核畸形.本文还对雏鹅新型病毒性肠炎与小鹅瘟的病理变化进行了比较分析.  相似文献   

5.
伪狂犬病病毒吉林分离株感染BHK-21细胞的超微结构变化   总被引:1,自引:0,他引:1  
以猪伪狂犬病病毒(PRV)吉林分离株PRV-JL感染体外培养的BHK-21细胞为模型,通过透射电镜对PRV的形态发生学和宿主细胞超微结构的动态变化规律进行研究。结果显示,PRV能导致BHK-21细胞圆缩,并发生细胞融合,形成合胞体;电镜观察到的病毒粒子呈球形或椭圆形,成熟的病毒粒子直径大小为140~210 nm,未成熟病毒粒子直径为90~150 nm,多呈中空状,部分呈致密核芯。病毒吸附于细胞后以膜融合的方式进入细胞,在胞核内复制,装配好的病毒粒子以出芽的方式离开细胞核,获得最初的囊膜,进入胞浆;在胞浆内的病毒粒子又利用高尔基体的膜结构合成第2层囊膜,形成完整的病毒粒子;最后包裹有完整病毒粒子的高尔基囊泡与细胞膜发生融合,将病毒粒子释放到细胞外。感染细胞超微结构变化主要表现为:细胞胞浆空泡增多,内质网扩张,线粒体增生、嵴肿胀、脱落,最后空泡化,整个细胞裂解、破碎。  相似文献   

6.
为了获得适宜雏鹅新型病毒性肠炎病毒(NGVEV)体外培养的细胞系,开展了NGVEV强毒株在鸭胚成纤维细胞(DEF)适应性和增殖特性的研究。结果表明,NGVEV强毒株经尿囊腔接种10日龄鸭胚传4代,取尿囊液接种DEF,第1代无明显细胞病变;第2代培养至72~96hDEF出现颗粒状缺失、脱落,但无典型蚀斑出现;第3代培养至96~120h,DEF形成大小不等、圆形或椭圆形的典型蚀斑;第5代以后的NGVEV可稳定适应于DEF,典型细胞病变出现于48~72h。取适应DEF的NGVEV感染DEF细胞后制作超薄切片经电镜观察,可见典型的腺病毒粒子,大小为70~90nm。NGVEV在DEF上的TCID5。值随着传代次数增加而增高,由第1代的10^1.23增加到第8代的10^8.02,最高毒价出现于96~144h,96~120h是收获病毒的最佳时间。  相似文献   

7.
对猪细小病毒(PPV)、牛疱疹病毒2型(BHV2)和犬腺病毒1型(CAV1)3种动物DNA病毒在宿主细胞内的增殖、释放方式以及所致细胞结构的变化,通过电镜进行了观察比较.(1)这3种动物DNA病毒的复制和装配过程均发生在细胞核内,以毒浆结构(Viroplast)或核内包涵体为增殖场所和物质基础,但并非都形成结晶样结构.(2)有囊膜的BHV2,其核壳体在细胞核内装配完成后,从核内膜上以出芽方式获得囊膜,然后进入核周池,聚集的病毒使核外膜向胞质方向隆起,形成病毒性包涵体而脱离核外膜,并逐渐向细胞膜的方向移动,最后从细胞膜的破损处以病毒包涵体形式释放到细胞间隙.而无囊膜的CAV1,核壳体在细胞核内装配完成后,从细胞核膜破损处或细胞核崩解后进入细胞质,待整个细胞崩解后才能释放出来.无囊膜的PPV,在核壳体装配完成后,成堆地以病毒流的方式,从扩张的核孔释放到细胞质中,待细胞崩解后再释放出来.(3)3种病毒增殖时,宿主细胞的固有细胞器,如线粒体、内质网以及溶酶体等均出现不同程度的超微结构变化,并能诱导宿主细胞出现一些新的结构,除毒浆结构外,还有管状结构、细纤维样结构、周期性结构和髓膜样结构等,其中周期性结构仅见于BHV2感染.  相似文献   

8.
40只2日龄四川白鹅口服感染雏鹅新型病毒性肠炎病毒,在不同阶段解剖发病和死亡雏鹅,电镜观察组织器官的病理变化发展规律,接种后第2天,十二指肠绒毛顶部上皮细胞发生坏死、脱落。随着感染时间延长,上皮细胞的坏死、脱落迅速向绒毛基部发展,并伴随固有膜炎性细胞浸润和坏死,病变向着空肠段发展,进一步发展为纤维素性坏死性肠炎,于小肠中后段形成假膜包裹肠内容物的栓塞物或直接由纤维素性渗出物与地不死肠粘膜混合凝固形成栓塞物阻塞肠腔,使外观膨大,肺充血和出血,肾充血、出血及肾小管上皮细胞变性。部分病例肝颗粒变性、脂肪变性,后期部分病例气管、腺胃上皮细胞脱落,早期部分病例心充血和出血,食道、胰腺及脑正常,电镜下可观察到小肠上皮细胞核畸形、固缩、核仁消失、核膜模糊和胞核崩解;胞浆严重空化,形成含有很多病毒粒子的“封入体”;粗面内质网扩张呈囊状,其上的核蛋白体严重脱落;线粒体外膜破裂或嵴断裂及空化,部分受到损害的线凿全充满大量的病毒粒子;形成肠道栓子的外层假膜有大量的病毒粒子、细菌以及坏死的肠上皮细胞,肝脏细胞粗面内质网严重扩张及部分线粒体肿胀、脊断裂;而心肌细胞粗面内质网的轻度扩张及胞核畸形。本文还对雏鹅新型病毒性肠炎与小鹅瘟的病理变化进行了比较分析。  相似文献   

9.
人工感染PRRSV仔猪肺和子宫细胞凋亡的电镜观察   总被引:4,自引:0,他引:4  
应用透射电子显微镜对仔猪感染猪生殖与呼吸综合征病毒(PRRSV)后不同时期肺和子宫凋亡细胞的超微形态结构进行了观察。结果表明,PRRSV可诱导宿主肺和子宫发生典型的细胞凋亡,表现为细胞的超微形态结构随着病毒感染进程出现不同的特征性变化,早期(感染后第8h至第3d)凋亡细胞多表现为细胞体积缩小,细胞质密度增强,染色质浓缩,核仁解体,内质网扩张;中期(感染后第5d至第9d)凋亡细胞体积显著缩小,细胞膜突起,线粒体增多,有凋亡小体形成;晚期(感染后第10d以后)凋亡细胞形态多表现为凋亡小体降解和消失,少数凋亡细胞在凋亡晚期表现为坏死细胞。肺细胞凋亡主要发生于肺巨噬细胞和肺泡上皮细胞,子宫细胞凋亡主要发生于子宫内膜细胞和内膜腺细胞。  相似文献   

10.
运用透射电镜术、原位末端标记技术(TUNEL)和流式细胞术对11只自然感染兔脑炎原虫獭兔的肾脏进行了细胞凋亡研究,5只健康长耳白兔用作对照。结果表明.凋亡细胞多见于远曲小管和集合管的上皮细胞。用透射电镜观察,初期的凋亡细胞,其细胞核的染色质高度凝集,边缘化,粗面内质网增多、扩张呈泡状;后期的凋亡细胞,其细胞质浓缩.细胞膜起泡,细胞核分裂成块状,最后形成膜包裹的凋亡小体。TUNEL法检测,病变轻微的细胞,胞核微缩,胞膜增厚;病变严重的细胞,其胞核体积明显缩小,胞膜皱缩,最后形成膜包裹的凋亡小体。流式细胞术检测,病兔可呈现明显的亚“G1”峰,凋亡细胞百分比与对照兔相比差异极显著(P=0.01),且病兔。肾细胞的周期也有所改变。结果表明,3种方法检测的病兔肾上皮细胞凋亡数均高于对照免。  相似文献   

11.
Chen S  Cheng AC  Wang MS 《Avian diseases》2008,52(1):173-178
The morphogenesis of the new type gosling viral enteritis virus (NGVEV) and the characteristic ultrastructural changes in the duck embryo fibroblasts (DEFs) were investigated by ultrathin sectioning and transmission electron microscopy after monolayer DEFs were experimentally infected with a virulent NGVEV strain. The investigation demonstrated that typical NGVEV particles were round, with a diameter ranging from 75 nm to 90 nm and that they were present in both the nucleus and cytoplasm of the infected DEFs. The mature virions contained nucleocapsids and nucleic acids. The virion penetrated the DEF, replicated, and matured in the nucleus, and they were finally released into the extracellular space via budding and disruption of the cytoplasmic membrane. With the appearance of progeny NGVEV, certain virus-related structures that were densely electron stained, which were circular, U-shaped, or irregular in appearance, could be observed in the cytoplasm of the infected DEFs. In this research, we first detected three types of intracytoplasmic inclusion bodies during the NGVEV infection, which always contained a number of NGVEV particles. Furthermore, we detected that NGVEV could induce apoptosis in DEFs, which had not been reported previously. The morphologic changes of apoptosis included shrinking of the apoptotic cells, chromatin condensation and margination, appearance of vacuoles on the cytoplasmic membrane, and the formation of apoptotic bodies. The mitochondria were ultracondensed and aggregated into compact clusters during apoptosis.  相似文献   

12.
In this study, apoptosis was induced by new type gosling viral enteritis virus (NGVEV) in experimentally infected goslings is reported in detail for the first time. After 3-day-old goslings were orally inoculated with a NGVEV-CN strain suspension, the time course of NGVEV effects on apoptotic morphological changes of the internal tissues was evaluated. These changes were observed by histological analysis with light microscopy and ultrastructural analysis with transmission electron microscopy. DNA fragmentation was assessed with a terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay and DNA ladder analysis. A series of characteristic apoptotic morphological changes including chromatin condensation and margination, cytoplasmic shrinkage, plasma membrane blebbing, and formation of apoptotic bodies were noted. Apoptosis was readily observed in the lymphoid and gastrointestinal organs, and sporadically occurred in other organs after 3 days post-infection (PI). The presence and quantity of TUNEL-positive cells increased with infection time until 9 days PI. DNA extracted from the NGVEV-infected gosling cells displayed characteristic 180~200 bp ladders. Apoptotic cells were ubiquitously distributed, especially among lymphocytes, macrophages, monocytes, and epithelial and intestinal cells. Necrosis was subsequently detected during the late NGVEV-infection phase, which was characterized by cell swelling, plasma membrane collapse, and rapidly lysis. Our results suggested that apoptosis may play an important role in the pathogenesis of NGVE disease.  相似文献   

13.
The histology and characteristics of mucins secreted by epithelial mucous cells of the digestive tract in yellow catfish, Pelteobagrus fulvidraco were investigated using light microscope and transmission electron microscope. The digestive tract was divided into a pharynx, oesophagus, U-shaped stomach (with a cardiac, fundic and pyloric part) and intestine, composed of anterior intestine, middle intestine and posterior intestine, which consisted of a mucosa (epithelial layer), lamina propria-submucosa, muscularis and serosa. A large number of isolated longitudinal striated muscular bundles were present in the lamina propria-submucosa of pharynx. Goblet cells were observed throughout the digestive tract, except in the stomach. In the cardiac and fundic stomach, a plenty of gastric glands were observed, whereas they were absent in the pyloric part. Numerous mitochondria and endoplasmic reticulum were observed in the columnar epithelial cells of the intestine, especially of the anterior part. The epithelial mucous cells contained neutral or other two mixtures of acid and neutral mucins, the first being the most common. The neutral mucin was the only type of mucins in the stomach, anterior intestine and middle intestine. The results of this study will be helpful for understanding the digestive physiology and diagnosing some gastrointestinal diseases in yellow catfish.  相似文献   

14.
人工感染鸭病毒性肠炎急性病例超微结构变化   总被引:1,自引:0,他引:1  
用鸭病毒性肠炎病毒(Duck enteritis virus,DEV)CH强毒株感染成年鸭复制鸭病毒性肠炎急性病例,分别于接种后不同时间,取心、肝、肾、脾、胸腺、十二指肠、法氏囊、脑和胰组织,制作超薄切片,电镜观察。结果表明:病变最早发生于肝和肾,而鸭死亡后以免疫器官和消化器官损伤最严重;各种细胞的变化主要表现为细胞肿胀,染色质或浓缩、碎裂或溶解,线粒体溶解成空泡样结构,其他细胞器破坏;脾、胸腺、法氏囊以及小肠固有层中的淋巴细胞在感染24h后,在出现细胞坏死的同时还出现较为明显的细胞凋亡变化;而鸭死亡后淋巴细胞主要表现为黑洞核样变化,整个细胞凝聚深染,染色质固缩,细胞浆均质深染,细胞膜模糊或不完整。  相似文献   

15.
Duck virus enteritis (DVE) is an acute and contagious herpes virus infection of duck, geese and swans with high morbidity and mortality. The development of specific mucosal immune system against duck enteritis virus (DEV) infection for ducks has been hindered by a lack of knowledge concerning the purification of immunoglobulin A (IgA) of duck. In the present work, the method for purification of duck immunoglobulin A was developed, and the induction of intestinal mucosal immune responses against DEV was studied by orally infected ducklings with virulent DEV. The results showed that a continuous increased DEV DNA levels were observed in blood and various organs examined of orally infected ducklings throughout the infection, which was accompanied by the development of infection in ducklings from mild progressed to severe pathological lesions. Furthermore, a marked increased level of DEV-specific IgA and IgG antibodies in bile, serum and the intestinal tract, as well as the density of IgA+ cells in intestine were detected between 1 and 12 days p.i., followed by a drastic reduction of the antibody levels and the density of IgA+ cells at 15 days p.i. The results indicate that the DVE infection can stimulate both IgA-dominated antibody immune responses in the intestinal tract, and IgG-dominated antibody systemic immunity in the serum of ducklings orally inoculated with virulent DEV. The severe lesions of the villus epithelial cells and the lymphoid organs can suppress the intestinal mucosal immune responses.  相似文献   

16.
应用透射电镜和超薄切片技术观察鸭病毒性肠炎病毒(Duck Enteritis Virus,DEV)CH强毒株人工感染成年鸭各组织器官的形态学特征。结果表明,脾脏、胸腺、法氏囊、十二指肠固有层中淋巴细胞除了坏死变化外还有很明显的凋亡变化,两者往往同时存在。疾病过程中,淋巴细胞凋亡数量明显增多。凋亡细胞的形态学改变是细胞体积缩小,细胞器结构正常,染色质初期浓集成团,聚集于核膜的周边,随后出现染色质凝聚,核碎裂以及凋亡小体形成等现象。淋巴细胞的坏死和凋亡共同造成了淋巴细胞的大量损耗,淋巴细胞的这种变化可能在鸭病毒性肠炎的发病机制中起着重要的作用。研究结果表明DEV急性感染可诱导成年鸭体内淋巴细胞的凋亡。  相似文献   

17.
鸭传染性产蛋减少症(暂定名)的病原分离初报   总被引:3,自引:0,他引:3  
本文对2010年在成年蛋鸭中流行的以产蛋下降为特征的未知疫病病原进行了初步鉴定。病原能在鸭胚、鸡胚和细胞上复制增殖,对鸭胚、鸡胚的致死率达100%。鸭胚病毒分离物不具有血凝性,在透射电镜下可观察到直径为50~100 nm、有囊膜带突起的病毒粒子。病毒对酸敏感、能耐受pH9的碱性环境,50℃1 h可使病毒失去感染能力。SPF鸡人工感染试验结果显示,感染鸡生长缓慢、致死亡率低、能回收病毒。说明引起鸭产蛋量下降的疫病病原是病毒性的,并导致鸡感染发病,我们将此病暂称为鸭传染性产蛋减少症。  相似文献   

18.
To determine the distribution and localization of new type gosling viral enteritis virus (NGVEV) in paraformaldehyde-fixed paraffin-embedded tissues of experimentally infected goslings, for the first time, an immunohistochemical (IHC) staining method was reported. Anti-NGVEV polyclonal serum was obtained from the rabbits immunized with purified NGVEV antigen, which was extracted by caprylic-ammonium sulphate method and purified through High-Q columns anion exchange chromatography. Three-day-old NGVEV-free goslings were orally inoculated with NGVEV-CN strain suspension as infection group and phosphate buffered saline solution (PBS) as control group, respectively. The tissues were collected at sequential time points between 0.5 and 720 h post inoculation (PI), and prepared for IHC staining and ultra-structural observation. The positive immunoreactivity could be readily detected in the lymphoid and gastrointestinal organs of infected goslings as early as 48 h PI, in the liver, kidney, pancreas and myocardium from 72 h, and in the cerebrum and cerebellum from 96 h, while it was hardly detected in the respiratory organs at any time. The positive staining reaction could be detected in NGVEV-infected goslings until 600 h PI, and no positive staining cell could be observed in the controls. The highest levels of viral antigen were found in the bursa of Fabricius (BF), thymus, proventriculus, gizzard and intestine tract, moreover, the liver, kidney, spleen, myocardium and pancreas were intensively and widely stained. The target cells had a ubiquitous distribution, especially included the epithelial cells, endothelial cells, superficial and crypt mucosal cells, glandular cells, fibrocytes, macrophages and lymphocytes, which served as the principal sites for antigen localization. The ultra-structural observation by transmission electron microscope (TEM) further indicated that NGVEV particles could be widely detected in the lymphoid and digestive organs of infected goslings from 72 h PI onwards. This work may be useful not only for offering a possibility of routine diagnosis of NGVE, but also for better understanding of the pathogenesis of the disease.  相似文献   

19.
猪繁殖—呼吸综合征病毒的形态学   总被引:3,自引:0,他引:3  
利用电子显微技术,对从上海某发病猪场分离到3株猪繁殖-呼吸综合征病毒(PRRSV)和标准美洲株(ATCC-VR2332)进行了形态特征的比较。结果表明,这4株病毒形态特征无显著差异。负染显示该病毒以球形为主,具有囊膜,囊膜上有纤突,大小为60-85nm。超薄切片可见病毒粒子大量存在于细胞浆内,有囊膜的直径为60-80nm,没有囊膜的直径为40-50nm,在细胞的线粒体,高尔基体和双基核膜内可见病毒粒子。在病毒增殖的同时,Marc-145细胞的显微结构逐渐发生破损,显示病毒的释放是通过破坏细胞膜结构的完整性来实现的。  相似文献   

20.
流感病毒受体在三种动物气管和肺脏分布的组织化学检测   总被引:1,自引:0,他引:1  
利用凝集素组织化学染色的方法,对岭南黄鸡、番鸭和BALB/C小鼠的气管和肺脏进行了流感病毒受体分布的检测。结果表明:在岭南黄鸡、番鸭和小鼠的气管粘膜层、粘膜下层、肺脏的细支气管和肺泡上皮细胞均有禽流感病毒受体的分布。番鸭和小鼠气管和肺脏的人流感病毒受体的分布范围和细胞类型与禽流感病毒受体的分布稍有差异,岭南黄鸡气管和肺脏未检测到人流感病毒受体的分布。研究结果为探讨流感病毒的感染机制和宿主特异性的差异提供了基础数据。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号