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1.
褐龙斑是雌性褐石斑鱼(Epinephelus bruneus)和雄性鞍带石斑鱼(E. lanceolatus)杂交产生的子代。作为杂交石斑鱼的新品种,国内外尚没有褐龙斑疾病的报道。2017年7月,某养殖场褐龙斑出现急性死亡,10 d内累积死亡率高达80%。现场调查发现,病鱼外观无明显异常,但反应迟钝,伏底死亡。临床检查和剖检可见脾和肾严重肿大、易碎。组织病理切片观察发现,各组织中存在数量不等的嗜碱性、细胞质均一、直径为10~15 µm的肿大细胞。超薄组织切片中发现,肿大细胞胞质内存在大量直径为130~150 nm的虹彩病毒样颗粒。使用特异性的PCR引物,从病鱼脾、头肾等组织中均检测到真鲷虹彩病毒(Red seabream iridovirus, RSIV)的高强度感染。测定了该病毒主要衣壳蛋白(Major capsid protein, MCP)基因1362 bp的全长编码区,构建了19种(株)虹彩病毒系统发育树,结果显示,该病毒属于虹彩病毒科肿大细胞病毒属RSIV类群。本研究首次描述了褐龙斑虹彩病毒病的组织病理特征,揭示了褐龙斑是RSIV新的敏感宿主,为杂交石斑鱼病毒病的诊断与防治提供了重要的参考依据。  相似文献   
2.
为研究水环境中Ni~(2+)对鲤鱼鳃和肝脏的组织损伤,将鲤鱼(Cyprinuscarpio)暴露在Ni~(2+)浓度为0、0.55、0.62、0.72、0.83、0.96、1.09、1.25mmol/L的水环境中进行急性毒性试验,并通过组织切片观察鳃和肝脏的组织病理变化。结果显示,Ni~(2+)对鲤鱼的96h半数致死浓度(LC_(50))为0.72 mmol/L,安全浓度(SC)为0.007 2 mmol/L。高浓度Ni~(2+)(1.25 mmol/L)试验组鲤鱼的鳃小片呼吸上皮细胞坏死、脱落,肝血窦淤血,肝细胞核固缩;中低浓度Ni~(2+)(0.72~1.09mmol/L)试验组鲤鱼的鳃小片呼吸上皮水肿浮离、细胞增生,血窦充血,肝细胞胞浆空泡化。表明水环境中的Ni~(2+)浓度高于0.007 2mmol/L时会对鲤鱼的鳃和肝脏造成急性毒性,导致鳃和肝脏出现明显的组织病理变化。  相似文献   
3.
Ganjare AB  Nirmal SA  Patil AN 《Fitoterapia》2011,82(7):1052-1056
Cordia dichotoma f. (Boraginaceae) is a small deciduous tree from India. The bark of was used in the treatment of ulcerative colitis (UC) and colic pain traditionally hence present work was undertaken to identify the phytoconstituent responsible for this activity. Apigenin is isolated by column chromatography from methanol fraction of crude methanol extract of C. dichotoma bark. Structure of apigenin is established by various spectroscopic studies. Apigenin (5 mg/kg, p.o.) showed significant healing and reduction in inflammatory enzymes when screened for UC. It can be concluded that apigenin from C. dichotoma bark may be responsible for the treatment of UC.  相似文献   
4.
The aim of this study was to evaluate the histopathological features in tissues of mice infected by human isolates (I, II, and III) or the reference M2903 strain of Leishmania braziliensis complex. BALB/c and C57Bl/6 mice were infected in the hind footpad with 106 stationary-phase promastigotes of L. braziliensis complex. The evolution of lesions was observed for 10 weeks and the animals were then euthanized and liver, spleen and popliteal lymph nodes were collected. Tissues were stained with hematoxylin and eosin and analyzed by immunohistochemistry assay. Increased thickness of infected footpads was observed in all animals, lesions were nodular and non-ulcerated. Mice infected with isolate I presented inflammatory infiltrates consisting predominantly of mononuclear cells in all tissues examined, and also a great number of megakaryocytes, compared with other isolates. Infection with isolate II led to an infected footpad enlargement not seen in other isolates. In addition, mononuclear infiltrates in the liver and hemosiderin in spleen were noted. Conversely, mice infected with either isolate III or M2903 strain only showed an increased number of megakaryocytes in spleen. All tissues examined had detectable amastigote forms of Leishmania by immunohistochemistry in all groups. Taking together, our results showed an unforeseen behavior of different isolates of L. braziliensis complex that led to diverse pathological findings.  相似文献   
5.
6.
本文研究了菌核病菌(Sclerotinid Sclerotiorum)侵染油菜叶片的组织病理学。其侵染过程包括:叶片表面侵染垫的形成,寄主表皮的机械直接侵入,侵染菌丝(平均直径16.4μm)的胞间扩展以及分枝菌丝(平均直径7.8μm)的胞间胞内扩展。结果还证实了木质部导管腔内及叶片其它部位菌丝体周围形成草酸盐晶体以及耐、感品系病菌侵染的差异。  相似文献   
7.
本文对产蛋母鸡发生鸡弧菌性肝炎后所表现出的临床症状及尸体剖检变化和病理组织学变化作了较为详细的观察与研究,为鸡弧菌性肝炎的进一步研究和临床诊断提供一定的理论依据  相似文献   
8.

Background

Transjugular liver biopsy (TJLB) is used in humans at risk of bleeding. There are no reports of its use in veterinary medicine.

Objective

To assess the efficacy and potential complications of TJLB in canine cadavers, and compare with samples obtained via needle liver biopsy (NLB) and surgical liver biopsy (SLB).

Animals

Twenty‐five medium and large breed canine cadavers.

Methods

Prospective study. TJLBs were procured through the right jugular vein. After biopsy, intravenous contrast and gross inspection were used to assess the biopsy site. Minor and major complications were recorded. NLBs and SLBs were then obtained. Histopathology was performed, and TJLB and NLB were compared for number of complete portal tracts (CPTs), length, and fragmentation. Pathologic process and autolysis were assessed in all samples.

Results

All TJLBs yielded liver tissue. The proportion of minor complications was 12/25 (48%), and major complications 16/25 (64%); 13/16 (81%) of the major complications were liver capsule perforation. In 21/25 (84%), the histopathology in the SLB was reflected in the TJLBs. For cases with minimal autolysis, median number of CPTs in TJLBs was 7.5, compared with 4 in NLBs (P = .018). Median length of TJLB specimen was 28 mm compared to 22 mm in NLBs (P = .007). Fragmentation rate was median of 1.25 for TJLB compared to 1.50 in NLBs (P = .11).

Conclusions and Clinical Importance

TJLB is technically feasible and achieves comparable results to NLB and SLB. The number of complications, in particular liver capsule perforation, was greater than expected. Further studies are indicated before clinical use is recommended.  相似文献   
9.
大黄鱼肝脏病变组织病理学观察   总被引:1,自引:0,他引:1  
采用石蜡切片和HE染色法,对不同生存条件下的大黄鱼以及肝脏病变的大黄鱼肝组织进行组织切片,在显微镜下进行组织病理学观察,采用酸水解法测定不同生存条件下以及患肝肿大的大黄鱼肝脏的脂肪含量,了解其变化情况。以野生大黄鱼的肝组织细胞结构为参照,初步探明了小网箱养殖大黄鱼的脂肪肝、肝肿大、肝胆汁淤积、肝淤血的组织病理变化情况,讨论了大黄鱼肝脏病变的原因和病变致死原因,并提出了防治措施。  相似文献   
10.
Histopathological changes induced by the root-knot nematode (Meloidogyne incognita) in five ornamental plants, specifically, Calendula (Calendula officinalis), Centaurea (Centaurea montana), Papaver (Papaver somniferum), Chrysanthemum (Chrysanthemum morifolium) and Dianthus (Dianthus caryophyllus), were investigated. Based on the galling index (GI), Centaurea was classified as susceptible, Calendula as moderately susceptible, and Papaver as moderately resistant, while Chrysanthemum and Dianthus were highly resistant to M. incognita infection. The histopathology of the galled roots of Centaurea, Calendula, and Papaver during later stages of infection showed that nematodes were localized entirely within the cortex and generally oriented horizontally to the vascular cylinder. Most of the females were mature, and a few of them were associated with egg masses. Giant cells with a variation in cell sizes were observed in the galled roots of all three of the plant species and exhibited a granular cytoplasm and hypertrophied nuclei as a typical reaction to nematode feeding.  相似文献   
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