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31.
研究了265头青年猪1 060个关节(附关节和腕关节各530个)骨软骨病的病理组织学变化.肉眼观察主要表现为患部关节软骨变色、充血,关节面粗糙、裂开、糜烂或凹陷,并根据其损伤程度进行分类,即正常、轻度、中度和严重,分别占21.7%、33.3%、29.0%、16.0%.显微观察特征为关节软骨局部增厚,软骨细胞增生、肥大;在一些区域软骨细胞变性、坏死,坏死区易形成裂隙;骨质内形成软骨岛.结论:青年猪有很高的骨软骨病发病率,后肢比前肢严重,并表现典型的骨软骨病组织病理学特征.  相似文献   
32.
Histologically verified tumours submitted to the Norwegian Canine Cancer Register from 1990 to 1998 were studied (n=14,401). The proportion of testicular tumours (n=345) was 2.4%, and the breakdown of histological tumour diagnoses is presented. The frequency of the most common histopathological types was 33% interstitial (Leydig), 26.4% Sertoli and 33.9% seminomas/germ cell tumours. The average age at diagnosis was 10 years, but was significantly lower for Sertoli cell tumours (8.6 years) than for the other tumour types. Following a histopathological re-evaluation, 22.5% of the original tumor diagnoses were modified. Proportional morbidity ratios were calculated and individuals from the breeds Shetland sheepdog and Collie were five times more likely to have testicular tumours than the overall average for the registry. Breed differences in the distribution of histopathologic types were observed. Shetland sheepdog and Collie were most commonly diagnosed with Sertoli cell tumours, while all tumours from Norwegian elkhound in this material were seminomas.  相似文献   
33.
为研究蛋鸡多发性肿瘤的病因,本实验对病鸡肿瘤组织进行病毒分离、培养及PCR检测,均扩增出针对J亚群禽白血病病毒(ALV-J)gp85基因序列的阳性条带;组织病理学观察显示发病鸡呈现髓细胞瘤、血管瘤以及纤维肉瘤等多发性肿瘤的病理变化;肿瘤细胞通过血液转移、浸润,在肝和脾组织形成局灶性或弥漫性肿瘤病灶。免疫组化染色显示肿瘤组织内,部分肿瘤细胞呈现阳性反应,表明只有部分肿瘤细胞存在ALV-J感染,而大部分肿瘤细胞检测结果呈阴性。这些病毒检测为阴性的肿瘤细胞可能是正常细胞转化为肿瘤细胞大量克隆化增殖的结果。  相似文献   
34.
The sensitivity of low‐field magnetic resonance (MR) T2* images for predicting the presence of meniscal lesions was determined in 12 dogs with naturally‐occurring cranial cruciate ligament rupture and three control dogs, using histopathology as the reference standard. Previously published grading systems were used to grade the severity of meniscal lesions on MR images, gross inspection and histopathology. Focal areas of increased signal intensity were detected in 11/12 symptomatic dogs and 3/3 control dogs. Lesions mimicking meniscal tears (pseudotears) were identified at junctions between meniscal margins and adjacent connective tissue in control dogs and dogs with naturally occurring disease. Histopathologic lesions were present in all menisci of both symptomatic and control dogs, including the menisci from two affected dogs that appeared grossly normal but were removed and submitted based on MR imaging findings. Histopathologic lesions identified included hyaline cartilage metaplasia and changes in the amount of ground substance and cellularity. The sensitivity of MR imaging for detecting the presence of meniscal histopathologic lesions was 90% in symptomatic dogs and 91% in control dogs. However, agreement between severity scores for the different tests was poor. Low‐field MR imaging is a sensitive test for predicting the presence but not severity of meniscal histopathologic lesions in dogs with naturally‐occurring cranial cruciate ligament rupture. Findings also supported previous studies indicating that histopathologic lesions can be present in dogs with grossly normal menisci. An improved grading system for comparing MR images and histopathologic severity of meniscal lesions in dogs is needed.  相似文献   
35.
An isolate of the fungus Fusarium culmorum constitutively expressing green fluorescent protein was used to investigate the infection process and host response of primary seedling roots and stem base leaf sheaths of soft wheat cv. Genio. Disease progress was assessed macroscopically by visual symptoms, microscopically by confocal laser scanning microscopy (CLSM) and via gene expression analysis of fungal and wheat genes by real‐time quantitative RT‐PCR. In the roots, CLSM investigations revealed an initial intercellular and subsequent intracellular colonization by fungal hyphae. The fungus invaded the rhizodermal layer and cortex but was not seen to colonize the stele. The fungus consistently expressed TRI5 (24, 48 and 96 h post‐inoculation), indicating that trichothecenes were being synthesized throughout this phase of infection and colonization. The expression of the six host defence‐associated genes (Wheatwin 1‐2, PR1, Chitinase, PAL, WIR1 and LOX) increased early in infection and decreased during later stages. In the stem base, CLSM observations revealed the fungus sequentially penetrating though the first, second and third basal leaf sheaths. Expression of TRI5 was initiated early in the infection of each leaf sheath. The expression of the host defence‐associated genes varied over time and across leaf sheaths, and all were also expressed in leaf sheaths which had not yet been in contact with the fungus. Expression of LOX and WIR1 were particularly enhanced in the third leaf sheath.  相似文献   
36.
对9例冠状病毒性脑脊髓炎仔猪病理组织学观察结果,本病是以脑脊髓软膜及实质的血管周围围以巨噬细胞和淋巴细胞;神经细胞变性、坏死;神经胶质细胞局灶性和弥散性增生为特征的非化脓性脑脊髓炎变化。病变在端脑、脑干、脊髓和半月状神经节都有分布,以小脑、延脑和桥脑的病变最重。免疫器官的免疫细胞反应是体液免疫和细胞免疫同时存在的混合免疫。  相似文献   
37.
Lens displacement resulting in secondary glaucoma is common in terrier breeds. This study was carried out to evaluate whether light microscopy was useful in detecting abnormal patterns in zonular fiber protein. Eyes from 63 dogs with glaucoma secondary to lens displacement were evaluated for the presence of abnormal zonular fiber morphology using the following stains: hematoxylin and eosin, periodic acid Schiff (PAS), Masson's trichrome and Verhoeff's elastin stains. Two distinct forms of abnormal zonular fiber morphology were recognized and designated as zonular fiber dysplasia (ZFD) and zonular fiber collagenization (ZFC). ZFD protein morphology was characterized by being tightly adherent to the nonpigmented ciliary body epithelium, exhibiting a distinct lamellar and cross-hatched pattern and staining strongly positive with PAS and trichrome stains, and staining negative with elastin stains. ZFD was predominant in terrier breeds (18 of 29) and Shar-Pei dogs (4 of 29). ZFC abnormality was characterized by excessive zonular fiber that was not tightly adherent to the ciliary body epithelium and staining positive with PAS, trichrome (blue for collagen) and elastin stains. Only 7 of 19 dogs with ZFC changes were terrier breeds, and there was no pattern in the breeds affected. Fifteen of the 63 dogs used in the study had normal appearing zonular fibers. The staining pattern in these dogs matched normal controls by staining positive with PAS and Verhoeff's elastin stains and had only minimal positive staining with Masson's trichrome stain. Results suggest that light microscopy is useful in detecting breed-related changes in zonular fiber morphology in cases of glaucoma secondary to lens displacement. These changes may correlate with the presence of abnormal zonular fiber proteins and might be important in the pathogenesis of primary lens displacement in terrier and Shar-Pei dogs.  相似文献   
38.
BACKGROUND: Osteogenic sarcomas are rare in rabbits, but cases involving the mandible, ribs, frontal bones, and tibia have been reported. OBJECTIVE: The purpose of this study was to describe the clinical and pathologic findings in a rabbit with osteosarcoma and multiple metastases with subcutaneous involvement. METHODS: A 1-year-old female Polish rabbit was evaluated for dysorexia, lameness, gait difficulties with the hind limbs, and the presence of 2 subcutaneous nodules, on the left thigh and in the dorsal region. A hard swelling was also present at the base of the tail. Radiographic findings revealed multiple abnormalities in several bones, which were more severe in the sacrococcygeal region and femur. Several areas of calcification involving the thorax and abdomen as well as skeletal muscles, also were noted. The thigh nodule was surgically removed, and cytologic and histologic evaluations were performed. Following the rabbit's death, postmortem radiographs were taken and necropsy was performed. Samples of tissues and organs, involved bone segments, and other subcutaneous nodules were collected and examined by cytology and histology. RESULTS: Both the subcutaneous nodules and the majority of tissues and organs contained neoplastic cells whose appearance was consistent with osteogenic sarcoma. CONCLUSION: Clinical, radiologic, and pathologic data supported a diagnosis of osteosarcoma with multiple metastases and subcutaneous involvement.  相似文献   
39.
应用扫描电镜和组织切片法研究球孢白僵菌侵染光肩星天牛幼虫体壁的过程以及寄主中肠发生的病理变化.结果表明:接菌后48h,芽管平均长度达到3.08μm时即可侵入幼虫体表.随着侵染时间延长,芽管伸长形成菌丝,逐渐萌发生成新的分生孢子,在后期菌丝间出现丝状物和网状结构,这2种现象在国内外未见报道.分生孢子多数以芽管方式侵入表皮,也可以产生附着胞再侵染.组织切片显示:侵染3天的幼虫腹部体腔中脂肪体组织变得模糊,细胞核不明显,马氏管出现空泡并变形.中肠围食膜被分解消失,肠壁肌肉层向内皱褶,排列紊乱,出现破裂,肠腔内变浑浊.  相似文献   
40.
杜林林  李梁  刘娟  吕雪 《兽医大学学报》2012,(10):1511-1515,1541
将犬分为空白对照组、模型组、复方苦芩预防组、复方苦芩治疗组,用犬细小病毒接种建立动物模型,复方苦芩防治犬细小病毒病,然后取样,光学显微镜和电子显微镜观察十二指肠黏膜细胞的病变和细胞凋亡,逆转录聚合酶链式反应(RT-PCR)法检测Bcl-2和Bax基因的mRNA表达。结果显示,与空白对照组比较,模型组犬十二指肠黏膜病变及炎细胞浸润,电镜下可见细胞收缩,核浓缩,深染,线粒体肿胀空化,细胞Bcl-2基因表达下调,Bax基因表达增加。与模型组相比,复方苦芩防治组肠黏膜病变轻,超微结构变化不明显,细胞Bax基因表达下调,Bcl-2基因表达上调。结果表明,复方苦芩可能是通过促进黏膜上皮细胞的增殖与恢复,调节Bcl-2,Bax基因表达,抑制犬细小病毒引起的十二指肠黏膜超微结构改变和细胞凋亡,而对细小病毒病犬的十二指肠组织结构起保护和促进恢复作用。  相似文献   
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