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441.
从内源性绵羊肺腺瘤反转录病毒(enJSRV)与外源性绵羊肺腺瘤反转录病毒(exJSRV)基因组结构的比较、enJSRV与绵羊肺腺瘤病(OPA)的关系、enJSRV在羊体内的表达及其系统发育分析等方面综述了enJSRV的研究进展,旨在为早期诊断及预防OPA提出新方法,为揭示该病的分子发病机理及探索其基因治疗提供新思路。 相似文献
442.
在大肠杆菌BL21(DE3)中分别表达了牛IFN-α基因、亚洲Ⅰ型口蹄疫病毒(FMDV)VP1和VP1 C末端基因,并纯化了所表达的蛋白。用透析的方法进行蛋白复性后制成油乳剂疫苗,经皮下多点注射免疫小鼠,以MTT法检测小鼠脾淋巴细胞经植物血凝素(PHA)刺激后的增殖反应活性;以液相阻断ELISA检测血清FMDV特异抗体的变化。结果表明,重组VP1(rVP1)和rVP1 C末端蛋白能单独诱发小鼠的体液免疫反应和微量的细胞免疫反应,而与重组牛IFN-α(rBoIFN-α)共同接种的小鼠,体液免疫反应和细胞免疫反应更为明显。 相似文献
443.
从辽宁省某鸡场疑似马立克氏病发病鸡外周血淋巴细胞中分离到1株适应鸭胚成纤维细胞生长的马立克氏病病毒(MDV),经蚀斑克隆和细胞传代,成功培育了1株增殖性能稳定的MDV细胞毒株,命名为HC135株;将HC135株第4代细胞培养物分别人工感染非免疫和不同疫苗免疫的SPF鸡,分析其对鸡的致病力,分离毒株攻毒对照组鸡的发病率为100%(10/10),死亡率为30%(3/10);HVT疫苗及HVT/SB1双价疫苗对分离毒株的保护指数分别为22.2和40.0。结果表明,该毒株可以突破HVT疫苗和HVT/SB1双价疫苗的免疫保护,具有特超强毒株(vv+MDV)的特点;也证实了我国商品鸡群中存在vv+MDV毒株。同时比较了HC135株与14株参考毒株的Meq基因序列,发现其Meq基因的ORF内没有基因片段的插入或缺失,推导的氨基酸存在点突变,这种突变符合高毒力毒株的变异规律。 相似文献
444.
为建立产志贺毒素Ⅱ型变异体(Stx2e)大肠杆菌的环介导恒温扩增(LAMP)检测方法,参照Gen-Bank中12条Stx2e序列和9条Stx2序列,针对Stx2e基因保守区域设计并合成4条引物,分别进行了反应条件优化、特异性试验、敏感性试验及模拟样品检测。结果显示,用所建立的LAMP方法对阳性样品扩增所得产物电泳后呈特征性梯状条带,阴性样品的扩增产物电泳后均无扩增条带。建立的LAMP方法对Stx2e+大肠杆菌的最低检出量为38CFU/管,敏感性高于PCR方法(3.8×103CFU/管)。LAMP和PCR对模拟样品检测结果的符合率为100%。该研究为仔猪水肿病的诊断和Stx2e+大肠杆菌的快速检测提供了新的方法。 相似文献
445.
使用培养的狭义伯氏疏螺旋体B31菌株制备可溶性抗原,建立羊莱姆病血清抗体的间接ELISA诊断方法。应用伯氏疏螺旋体阴性、阳性血清评价该方法的特异性和敏感性。根据所建立的方法对从甘肃省甘南地区采集的450份羊血清进行检测。结果显示,该方法对羊莱姆病的阳性检出率和阴性符合率分别为90.1%和90.0%,与羊霉形体、布鲁氏菌、弓形虫以及羊无浆体、巴贝斯虫、泰勒虫等常见蜱传播病原的阳性血清之间没有交叉反应。甘肃省甘南地区夏河县、临潭县和卓尼县羊莱姆病的感染率分别为3.3%、6.1%和4.1%,甘南地区的平均感染率为5.1%。结果表明,本研究所建立的方法能够用于羊莱姆病的血清学诊断,甘南地区可能存在莱姆病的自然疫源地。 相似文献
446.
Veljko Strajina M.D. Vladimir Živković M.D. Ph.D. Slobodan Nikolić M.D. Ph.D. 《Journal of forensic sciences》2013,58(2):544-547
Anomaly in the anterior papillary muscle (APM) is known to cause left ventricle outflow tract (LVOT) obstruction, and this rare congenital condition could be a cause of sudden cardiac death. This anomaly and its hemodynamic effects is similar to valvular heart disease. In our two described cases, in which cause of death was, respectively, hypertrophic cardiomyopathy and suicide by hanging, the cephalad portion of the left APM was inserted directly into the ventricular surface of the anterior mitral leaflet and chordae tendineae were absent in the area of the direct anomalous muscle insertion; the aberrant papillary muscle was very large and showed an exaggerated anterior displacement within the left ventricular cavity. The described anomaly is a cause of LVOT obstruction. This condition is considered to be rare, although incidence estimates do not exist. In the absence of other possible causes, this finding may indicate arrhythmia as being the immediate cause of death. 相似文献
447.
Rossana Cecchi M.D. Paola Frati M.D. Oriana Capri M.D. Luigi Cipolloni M.D. 《Journal of forensic sciences》2013,58(6):1636-1639
Sudden death following acute hypotension due to an undiagnosed pheochromocytoma (PHEO) is a rare event. Moreover, histopathology of the myocardium in such cases is rarely reported. We present a case of a woman who died during delivery. A 37‐year‐old parturient, who was 38 weeks pregnant, suffering from neurofibromatosis underwent a cesarean section following peridural anesthesia. Acute hypotension, acute intra‐operative pulmonary edema and supraventricular paroxysmal tachyarrhythmia occurred during delivery, followed by death. The autopsy revealed the presence of a PHEO, confirmed immunohistochemically with chromogranin‐A (CgA), CD20 antibody (L26), anti‐Keratocan antibody (KER‐1) and neuron‐specific enolase (NSE), and a PHEO‐induced cardiomyopathy. The physiopathology of both stress‐induced cardiomyopathy and PHEO‐induced cardiomyopathy, as well as the role of anesthesia in provoking the death, are discussed. The association of an undiagnosed PHEO with neurofibromatosis as the cause of sudden death in pregnancy is an obstetric urgency that raises forensic pathology issues. 相似文献
448.
MingChang Zhang M.D. Ling Li M.D. David Fowler M.D. Ziqin Zhao M.D. Dengming Wei M.D. Yang Zhang B.S. Allen Burke M.D. 《Journal of forensic sciences》2013,58(5):1171-1174
There are few autopsy studies of patients dying suddenly with obstructive sleep apnea (OSA). Twenty‐five forensic autopsies of unexpected sudden death in individuals with OSA were reviewed. The causes of death were as follows: cardiomyopathy (n = 11); sudden unexpected death without morphologic findings (SUDNA, n = 6); and other cardiovascular diseases not related to OSA (n = 8). The cardiomyopathy group comprised five hearts with concentric left ventricular hypertrophy without dilatation and six with left ventricular diameter >4 cm (dilated cardiomyopathy). Four of six hearts in the SUDNA group showed right ventricular dilatation compared with seven of 11 showed cardiomyopathy and one of eight miscellaneous. The degree of obesity was greatest in the dilated cardiomyopathy group (10 of 11 obese) followed by the SUDNA group (four of six obese). The cardiac findings in patients dying suddenly and unexpectedly with OSA include nonspecific cardiomyopathy, other cardiac conditions, and hearts without a morphologic cause of death, which show frequent right ventricular dilatation as the only finding. 相似文献
449.
Isabelle Le Blanc‐Louvry M.D. Ph.D. Fréderique Papin M.D. Emmanuelle Vaz M.D. Bernard Proust M.D. Ph.D. 《Journal of forensic sciences》2013,58(6):1640-1643
After strangulation, cervical arterial injuries (CAI) are uncommon. We report three unusual cases where strangulation induced immediate stroke. CAI were examined using brain CT scan and Doppler ultrasonography in the three cases and then by autopsy in one of the victims. One of the two victims who survived the attempted strangulation had a unilateral carotid dissection, whereas in the other victim, no arterial dissection or thrombosis was observed. As regards the deceased victim, the autopsy confirmed the bilateral dissection showed on CT scan and Doppler ultrasonic examination and revealed that both carotid arteries were dilated up to two times the normal diameter. Microscopic examination showed a major bilateral hemorrhagic dissection of the media with obliterating fibrous endarteritis lesions associated with inflammatory damage. CT scan with arteriography does not demonstrate all the different types of arterial injury, particularly atheromatous embolism, direct compression, or prolonged spasm. Thus, traditional autopsy remains an essential forensic tool after strangulation to show the type of CAI. 相似文献
450.
用番鸭白点病病毒人工感染雏番鸭后第 1、3、5、7、1 0、1 4d分别采集免疫器官和消化器官进行病理剖检和病理组织学观察 ,并测定血浆中的丙二醛 (MDA)和一氧化氮 (NO)含量 ,以研究白点病的发病机理。结果 ,感染后第 1d ,胸腺、脾、腔上囊开始出现肿大、出血和充血的现象 ,第3～ 7d病变较严重。胸腺以淋巴细胞坏死和减少为主要病变 ;脾除了淋巴细胞坏死和减少外 ,还有单核细胞浸润和髓窦红细胞淤积现象 ;腔上囊以淋巴细胞坏死和单核细胞浸润为主要病变。染毒后第 3d ,食管、腺胃、肝、胰、小肠等开始出现少量炎性细胞和红细胞浸润 ,第 5d时各消化器官都有不同程度的变性和坏死 ,随着病程的发展 ,炎性细胞和红细胞逐渐增多。第 1 0d时病变开始减轻 ,炎性细胞和红细胞浸润减少。血浆MDA含量在感染后第 3d开始升高 ,到第 5d时感染组显著高于对照组。血浆NO水平在感染后第 1d就开始升高 ,至第 7d达顶峰。试验结果提示 ,MDA和NO参与了白点病的病理过程 相似文献