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141.
为了解安徽省A型禽流感病毒感染情况,2018年4—5月,在安徽省北部、中部和南部7个市,随机选取各类型场点173个,在每个场点内随机采集35份咽喉/泄殖腔和环境拭子样品,使用荧光RT-PCR进行A型、H5亚型、H7亚型流感病毒核酸检测。结果显示:在4个养殖场、3个活禽批发市场和17个农贸市场检出了A型禽流感病毒,场点阳性率分别为2.9%(4/140)、75.0%(3/4)、80.9%(17/21),未检出H5和H7亚型流感病毒核酸;A型禽流感群体流行率为11.2%(95%CI:6.5%~15.8%),个体流行率为1.2%(95%CI:0.9%~1.5%);活禽交易市场内,禽群感染A型禽流感病毒的风险较高(OR=136,95%CI:32.7~549.4)。结果表明,A型禽流感病毒在养殖和交易环节存在一定的污染,而在活禽交易市场的污染更严重,是今后禽流感防控的重点,需继续加强活禽交易市场的管理和消毒灭源工作。 相似文献
142.
为了解北京市猪伪狂犬病野毒感染情况,2017年从北京市7个区157个养猪场(户),采集5 469份猪血清样品,采用猪伪狂犬病病毒(PRV)gE抗体酶联免疫检测试剂盒进行血清学调查。结果显示:北京市7个区均有不同程度的PRV野毒感染,平均样品阳性率为53.36%。其中:经产母猪阳性率最高(58.28%),其次是育成猪(57.55%)、育肥猪(54.49%),后备母猪阳性率最低(37.46%);散养户的样品阳性率较高,为66.42%,规模猪场的阳性率较低,为47.71%。调查结果表明,北京市PRV野毒感染较为严重,对猪场采取伪狂犬病净化和综合防控措施势在必行。 相似文献
143.
To study the effect of luteolin on blood indexes,liver and kidney in mice with acute mercury poisoning,28 mice were randomly divided into four groups:Control group (intraperitoneal injection 0.9% saline),luteolin group (lavage 100 mg/kg luteolin),mercuric chloride group (intraperitoneal injection 4 mg/kg mercury chloride) and mercury chloride+luteolin group (intraperitoneal injection 4 mg/kg mercuric chloride,lavage 100 mg/kg luteolin).The activities of ALT in serum,AST,CREA and BUN contents,blood WBC,RBC,HGB content and GSH and MDA contents of liver tissue were detected.Morphological changes of liver and kidney tissues were observed.The results showed that compared with the control group,the activities of ALT and AST of mercuric chloride group were extremely significantly increased (P < 0.01),serum CREA,BUN,blood WBC and liver tissue MDA contents were significantly increased (P < 0.05) while blood RBC,HGB and liver tissue GSH contents were significantly decreased (P < 0.05).Liver,kidney pathological changes were obviously.Compared with mercuric chloride group,the activities of ALT,AST in serum,CREA,BUN,blood WBC and liver tissue MDA contents of mercuric chloride+luteolin group were significantly decreased (P < 0.05),while blood RBC,HGB and liver tissue GSH contents were significantly elevated (P < 0.05).Liver,kidney pathological changes were attenuated obviously.The poisoning were characterized by inflammation and the occurrence of anemia when acute mercury poisoning occurred,liver and kidney showed different degrees of injury in mice.Luteolin could reduce the toxic effects of acute mercury poisoning on blood,liver and kidney. 相似文献
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考虑了一类具有多个时间点重置执行价格的欧式熊市(或牛市)重置权证定价.应用鞅定价方法和多维正态分布函数,得到了该类权证价格的显示解和Δ对冲策略,推广了Gray和Whaley的单时点重置权证定价模型. 相似文献
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148.
对装配过程中发生开裂的6307E深沟球轴承,采用宏观观察、显微观察、硬度检测、扫描电镜观察、能谱微区成分分析等手段,并结合装配工艺进行了综合分析。分析结果表明,6307E深沟球轴承开裂处显微组织正常、硬度符合技术要求、化学成分正常且无原材料缺陷,裂纹处存在明显的氧化特征,可知该裂纹为轴承装配前就存在的淬火裂纹。 相似文献
149.
Min Zhang Dan Zheng Zhimei Peng Yuting Zhu Rongrong Li Qiong Wu Yan Li Hongyi Li Weihua Xu Mao Zhang Qichun Hung Yanfa Sun 《The Journal of Poultry Science》2021,58(2):131
In this study, signaling pathways and key differentially expressed genes (DEGs) involved in lipid metabolism in muscle and fat tissues were investigated. Muscle and abdominal fat tissues were obtained from 35-day-old female broilers for RNA sequencing. DEGs between muscle and fat tissues were identified. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of DEGs were performed. A total of 6130 DEGs were identified to be significantly enriched in 365 GO terms, most of which were involved in biological processes, cellular components, and molecular functions in muscle and fat tissues. Three important lipid signaling pathways (pyruvate metabolism, the insulin signaling pathway, and the adipocytokine signaling pathway) were identified among the fat and muscle tissues of broilers. The key common DEGs in these pathways included phosphoenolpyruvate carboxykinase 2 (PCK2), acetyl-CoA carboxylase 1 alpha and beta (ACACA and ACACB), and the mitogen-activated protein kinase (AMPK) gene family. Hence, our findings revealed the pathways and key genes and gene families involved in the regulation of fat deposition in the muscle and fat tissues of broilers. 相似文献
150.
MAO Ran LI Qing-quan SHI Yan LAN Xiang-li WANG Min ZONG Ze-jun XIA Guo-zhong HAN Tian-long 《中国畜牧兽医》2015,42(12):3308-3314
In order to explore the effect of different L-lysine levels added in semen dilution on the fresh Dorper sheep quality stored at liquid state,3 health Dorper ram were used to collect semen which were equal-packaged and added to solution containing different levels (0,0.1,0.2,0.3,0.4 and 0.5 g) L-lysine in 120 mL diluent and at 0,6,24,30,48,54,72 and 78 h,the sperm motility,membrane integrity and acrosome integrity were detected.The results showed that the sperm motility in groups added 0,0.1 and 0.2 g L-lysine were higher than other groups,and that in 0.4 and 0.5 g L-lysine groups decreased faster than other groups;The sperm motility in 0.5 g L-lysine group reduced to 0 at 30 h,and it reduced to 0 at 48 h in the group added 0.4 g L-lysine;The effective survival time and survival index in the group added 0.1 g L-lysine was higher than other groups (P< 0.05);The membrane integrity of 0.1 g group was the highest,that had no significant difference with control group from 0 to 54 h (P >0.05),while after 72 h the two groups had significant differences (P< 0.05).The membrane integrity in 0.4 and 0.5 g groups were the worst,and that was significant different with other groups (P< 0.05);The acrosome integrity of 0.1 g group was the highest which had no significant difference with control group (P >0.05),0.4 and 0.5 g groups were the worst,the difference between them was not significant (P >0.05),while was extremely significant difference with other groups except for 0 and 6 h (P< 0.01).The results suggested that dilution added a high concentration of L-lysine could inhibit sperm quality,when the count of L-lysine was more than 0.2 g,sperm quality was significantly decreased,adding 0.1 g L-lysine could improve Dorper sheep fresh sperm quality stored at liquid state. 相似文献