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91.
刘荭 《水产学报》2004,28(6):695-702
从GenBank中查找出乙型野田村病毒组中海水鱼类各病毒的序列,并用Sequencher多重序列比较软件将其分到条纹踢神经坏死病毒(striped jack nervous necrosis virus,SJNNV)组、条纹星鲽神经坏死病毒(barfin flounder nervous necrosis virus,BFNNV)组、红点石斑鱼神经坏死病毒(redspotted grouper nervous necrosis virus,RGNNV)组和虎斑东方纯神经坏死病毒(tiger puffer nervous necrosis virus,TPNNV)组4个基因型的组别中。用DNAsis序列比较软件比较同一基因型各基因序列之间的同源性,均在815%以上;不同基因型之间序列的同源性,均在66%以下。结合Premier引物设计软件和Sequencher序列多重比较软件,设计了4对引物,采用逆转录聚合酶链式反应(RT—PCR)来鉴别这4个不同的基因型。对从深圳口岸进境的产地为台湾的海水鱼苗和广东、福建两省养殖的主要海水鱼类进行检疫和监测,结果在进境的海水鱼苗中检出有RGNNV基因型的VNNV,在福建和广东省养殖的石斑鱼成鱼和鱼苗的病鱼体内均检测到RGNNV基因型的VNNV,对上述扩增产物基因序列进行比较,相似性均在96.5%以上,推导出的氨基酸序列与玛拉巴石斑鱼神经坏死病毒(MNNV)序列相似性均为100%。  相似文献   
92.
为了解楚雄州部分地区的猪瘟免疫情况,利用酶联免疫法(ELISA)对楚雄市、南华县和禄丰县随机采取的393份血清进行猪瘟抗体检测,并对各县(市)的调查数据加以比较,了解猪瘟在楚雄州部分地区的免疫情况。结果显示,楚雄州部分地区均有较高的猪瘟抗体阳性率,各县(市)的猪瘟抗体阳性率都在80%以上,有的县(市)猪瘟抗体甚至达到了100%。说明楚雄州部分地区的猪瘟免疫效果较好,猪瘟免疫成功。  相似文献   
93.
AIM:To observe the expression of tumor necrosis factor α (TNF-α) and nuclear factor κB (NF-κB) in the renal tissue of the rats with contrast-induced nephropathy (CIN). METHODS:Male Sprague-Dawley rats (n=96) were randomly divided into control group (n=48) and CIN group (n=48). The model rats in CIN group were intravenously injected with iodinated contrast media (76% compound diatrizoate injection,10 mL/kg), while the rats in control group were injected with the same volume of saline. Six rats in each group were sacrificed at 6 h, 12 h, 24 h, 48 h, 72 h, 5 d, 10 d and 15 d after intravenous injection, respectively, and the blood and kidney samples of the rats were obtained. The renal tubular injury was assessed by histological examination (HE staining). The expression of kidney injury molecule-1 (KIM-1), TNF-α and NF-κB at mRNA and protein levels in the renal tissues were semiquantitatively measured by the methods of RT-PCR and immunohistochemistry, respectively. The correlations between the expression of TNF-α, NF-κB and tubular injury score, KIM-1 expression in renal tissue of CIN group were analyzed. RESULTS:The levels of serum creatinine (SCr) and blood urea nitrogen (BUN) in control group were not changed between different time points (P>0.05). The levels of SCr and BUN in CIN group displayed significant increases at different time points (except 15 d) compared with control group (P<0.05). The renal tubular injury score in CIN group was significantly higher at all time points than that in control group (P<0.05). The expression of KIM-1, TNF-α and NF-κB at mRNA and protein levels up-regulated significantly at 6 h and the peaking of KIM-1 expression was at 24 h, while the peaking of TNF-α and NF-κB expression was at 48 h in CIN group. The expression of KIM-1,TNF-α and NF-κB was significantly increased in CIN group compared with control group except at 15 d (P<0.05). The expression of TNF-α and NF-κB at mRNA and protein levels showed close correlations with renal tubular injury score (r=0.843, 0.758, 0.743 and 0.707, P<0.05). The expression of TNF-α and NF-κB at mRNA and protein levels was also positively correlated with KIM-1 expression (r=0.863, 0.807, 0.839 and 0.855, P<0.05). CONCLUSION:The expression of TNF-α and NF-κB at mRNA and protein levels in the renal tissues of CIN group is up-regulated and is closely related with renal tubular injury, indicating that the inflammatory response is involved in the pathogenesis of CIN.  相似文献   
94.
AIM:To establish a rat hyperlipidemia model for studying the aortic expression of heat shock protein 22 (HSP22), tumor necrosis factor alpha (TNF-α) and endothelial nitric oxide synthase (eNOS) and the effect of atorvastatin intervention. METHODS:Hyperlipidemia model was established in SD rats. Afterwards, the rats were divided into normal control group, high fat group and high fat+atorvastatin intervention group. The expression of HSP22 and TNF-α in the rat aortas was detected by immunohistochemical assay and the expression of eNOS was assessed by Western blotting. RESULTS:No detectable expression of HSP22 and TNF-α in the normal control group was observed. However, the expression of HSP22 and TNF-α was positive in the high fat group and the atorvastatin intervention group. The mean densities of HSP22 and TNF-α positive particles were significant lower in the atorvastatin intervention group as compared with high fat group (both P<0.05). The expression of eNOS protein in the high fat group and atorvastatin intervention group was significantly lower than that in normal control group (P<0.01). However, no marked difference of eNOS protein expression between high fat group and atorvastatins intervention group was observed. CONCLUSION: The expression of HSP22 and TNF-α in the rat aortas is increased in the hyperlipidemia rat model. This effect can be restored by atorvastatin treatment. The expression of eNOS in the rat aortas is decreased in the hyperlipidemia rat model, but this tendency could not be attenuated by atorvastatin.  相似文献   
95.
观察3种方法治疗雏鹅病毒性肝炎的疗效,选出较好的治疗方案,以提高雏鹅病毒性肝炎的治愈率。分别进行人工感染预防及治疗试验和临床治疗试验。在临床治疗试验中选自然发病的莱茵雏鹅共5466只,将患鹅随机分为4组,分别采用保肝散、病毒灵、保肝散加病毒灵治疗,并设空白对照组。结果表明,保肝散配合病毒灵组治疗效果最好,治愈率达96.05%;保肝散组次之,为77.97%;病毒灵组再次,为72.18%;对照组为14.72%。采用保肝散配合病毒灵组治疗雏鹅病毒性肝炎高于其他两种方法,为临床治疗该病提供了确实可行的治疗方法。  相似文献   
96.
97.
Global spread and evolution of viral haemorrhagic septicaemia virus   总被引:1,自引:0,他引:1  
Viral haemorrhagic septicaemia virus (VHSV) is a rhabdovirus that infects over 48 species of teleosts and is lethal in many. VHSV threatens marine and aquatic fisheries. VHSV was first discovered outside Europe in 1988 in fish from the Pacific coast of North America. In 1994, VHSV was discovered in Newfoundland. In 2003, VHSV was isolated from fish in Lake St. Clair (Michigan and Ontario). In this study, we used 46 nucleotide sequences for the glycoprotein gene from 12 studies and 150 nucleotide sequences for the nucleoprotein gene from nine studies. We combined phylogenetics and a geographic information system to visualize the transmission paths of VHSV lineages. We also reconstructed the spread of VHSV lineages through optimization of geographic data for viral isolates on phylogenetic trees. We demonstrate that VHSV was transmitted from the North Atlantic Ocean and/or Baltic Sea to the Atlantic coast of North America and Japan in independent events. From the Atlantic coast, the virus was transmitted independently to the Laurentian Great Lakes and the Pacific coast of Canada and the contiguous United States. From the Pacific Northwest, the virus was transmitted to Asia and Alaska in independent events. These results clarify the debate ongoing in the literature on the geographic spread of VHSV.  相似文献   
98.
99.
Viral haemorrhagic septicaemia (VHS) is a well-characterized disease of rainbow trout, Oncorhynchus mykiss, which has also caused economic losses in marine turbot farms in the British Isles. We have previously demonstrated that turbot, Scophthalmus maximus, are susceptible to isolates of viral haemorrhagic septicaemia virus (VHSV) that are endemic in the marine environment, highlighting a potential risk to marine aquaculture. Given the increasing interest in the intensive rearing of additional aquaculture species such as Atlantic cod, Gadus morhua, and Atlantic halibut, Hippoglossus hippoglossus, this study aimed at investigating the susceptibility of these species to VHSV. Both species were found to be largely resistant to VHS following immersion challenge with a selection of 18 isolates, representing the known marine VHSV genotypes. Only one and two VHSV-associated mortalities occurred out of a total of 1710 and 1254 halibut and cod, respectively. These findings suggest that there is a low direct risk to the development of commercial cod and halibut aquaculture from the existing endemic reservoir of VHSV. This study, coupled to field observations has, however, highlighted the fact that both species can become infected with VHSV. The known adaptability of RNA viruses, together with the selection pressures associated with intensive aquaculture would thus advocate a cautious approach to VHSV surveillance within these emerging industries.  相似文献   
100.
In this study, the possible influence of temperature on infectious pancreatic necrosis virus (IPNV)-induced apoptosis in a zebrafish liver epithelium (ZLE) cell line was investigated. At a lower temperature (18 degrees C), there was expression of viral proteins VP2 and VP3 at 4 h post-infection (p.i.). At this time no expression was found in the high temperature group at 28 degrees C. The cell survival ratio was 52 and 18% at 24 and 48 h p.i., respectively, during IPNV infection at 18 degrees C. In addition, we assayed for apoptosis in IPNV-infected cells with terminal deoxynucleotidyl transferase (TdT)-mediated end labelling (TUNEL) of DNA at different dosages of virus. We found a ratio of apoptotic cells of 8 and 25% at 12 and 18 h p.i., respectively, in the multiplicity of infection (MOI) 1 group. The MOI 10 group had 20 and 45% apoptotic cells at 12 and 18 h, respectively. Furthermore, at 18 degrees C IPNV activated the caspase-8 and 3 from 1.5 to 2 times at 12 and 18 h p.i., respectively. Taken together, these findings suggest that successful virus replication occurs at the low temperature (18 degrees C) compared with the non-permissive temperature of 28 degrees C. Thus, IPNV replication is capable of activating caspase-8 and -3 and inducing host apoptosis.  相似文献   
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