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81.
对野生动物非法交易案件进行信息特征分析,可以把握案件的发生规律,提供决策者参考,以便有针对性预防和打击犯罪,更好地保护野生动物资源。本研究应用大数据分析的方法,对野生动物非法交易犯罪案件的文本数据进行结构化处理,建立了word2vec模型。从犯罪因素的角度统计分析了本类案件的信息特征,包括侵害人的特征、作案行为特征、侵害的动物或动物制品、侵害的时间和案件发生的地点等。在梳理基本特征的基础上应用关联算法构建了关联规则。根据特征分析和关联规则,提出了开展季节性防控、对特定群体和场所进行有针对性预防、对上游下游犯罪进行联动打击、与网管等多部门合作,运用现代科技成果进行打击和防范的对策建议。 相似文献
82.
Chlamydia abortus is one of the most common abortive agents worldwide in sheep. Few studies have been reported C. abortus infection among sheep in Egypt but the available data is scarce. The objective of the present study was to determine the seroprevalence of C. abortus among sheep, the associated risk factors and its molecular characterization. The present study was conducted on 675 sheep in six Governorates at Northern Egypt. Data analysis confirmed the presence of antibodies against C. abortus in 93 out of 675 sheep. The logistic regression model was fitted to identify the associated risk factors with C. abortus infection. The results revealed that C. abortus increased significantly in ewes (OR = 4.04, 95 %CI: 1.44−11.28) during autumn season (OR = 3.6, 95 %CI: 1.64–8.28), in ewes with a history of abortion (OR = 1.4, 95 %CI: 0.87–2.50) and in farm where no lambing pen (OR = 2.2, 95 %CI: 1.30–3.94) or abscence of post abortion measures (OR = 1.96, 95%CI: 1.23-3.12). In addition, age, flock size and exchange of breeding ram had no significant effect on prevalence of chlamydiosis. Also, PCR assay was confirmed presence of C. abortus as accusative pathogen in aborted ewe and the genetic characterization of Egyptian C. abortus strain revealed 100 % identity with another strain from Iraq. A control program should be applied to reduce economic losses and risk of human infection. 相似文献
83.
84.
Atsushi KIMURA Yo-Han KIM Kazuyoshi HASHIZUME Akira ITO Katsuyuki MUKAI Keiichiro KIZAKI Shigeru SATO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(5):829
We investigated the effect of oral administration of β-cryptoxanthin (β-CRX) on its serum concentration and peripheral neutrophil functions by the chemiluminescence (CL) response in Holstein cattle. A single oral administration of β-CRX was performed for serum β-CRX concentration (0, 0.05, 0.1, or 0.2 mg/kg body weight [BW]) and for peak CL response of peripheral neutrophils (0.2 mg/kg BW). The serum β-CRX concentration was peaked on 2 days after, similar to peak CL response on 3 days after β-CRX administration. Therefore, a single oral administration of β-CRX (0.2 mg/kg BW) induces higher serum concentration and concurrently enhances bactericidal ability of peripheral neutrophils in Holstein cattle. 相似文献
85.
Akiho KATAYAMA Ayako MIYAZAKI Naohito OKAZAKI Teruko NAKAYAMA Osamu MIKAMI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(6):931
A total of ten 1–2-year-old rabbits died within 2 weeks at a facility in Ehime prefecture in May 2019. Necropsy revealed liver discoloration and fragility, hemorrhage of some organs and blood coagulation failure. On histopathologic examination, necrotizing hepatitis was a common finding, together with fibrin thrombi in the small vessels and hemorrhage in some organs. Rabbit hemorrhagic disease (RHD) virus gene was detected in liver samples, and viral particles of approximately 32 nm in diameter were found in the cytoplasm of degenerated hepatocytes by electron microscopy. Phylogenetic analysis based on the partial VP60 gene sequence classified it as Lagovirus europaeus GI.2/RHDV2. This is the first confirmed outbreak of RHD caused by globally emerging GI.2/RHDV2 in Japan. 相似文献
86.
High oxalate consumption has been recognized as a risk factor for renal calcium oxalate stones in companion animals (dogs and cats). However, the cellular signaling involved in oxalate-induced dysfunction in renal tubular epithelial cells remains not fully elucidated. In this study, Mardin–Darby canine kidney (MDCK) cells, an epithelial cell line derived from canine kidney tubule, were tested for cell proliferation activity and barrier function after being exposed to sodium oxalate (NaOx). Further, the involvement of Wnt/β-catenin in NaOx-induced renal epithelial barrier dysfunction was evaluated. MDCK cells treated with NaOx exhibited reduction in cell proliferation and migration. Besides, NaOx exposure led to a decrease in transepithelial electrical resistance and an increase in paracellular permeability. The deleterious effects of NaOx on epithelial barrier function were related to the suppressed abundance of tight junction proteins including zonula occludens, occludin, and claudin-1. Of note, protein levels of β-catenin and phosphorylated (p)-β-catenin (Ser552) in MDCK cells were repressed by NaOx, indicating inhibitory effects on Wnt/β-catenin signaling. An inhibition of glycogen synthase kinase-3β (GSK-3β) by SB216763 enhanced the abundance of β-catenin and p-β-catenin (Ser552), and protected against epithelial barrier dysfunction in NaOx-treated MDCK cells. The results revealed a critical role of Wnt/β-catenin signaling in the epithelial barrier function of MDCK cells. Activation of Wnt/β-catenin signaling might be a potential therapeutic target for the treatment of oxalate-linked renal stones. 相似文献
87.
构建柔嫩艾美尔球虫ADF基因和鸡IL-2基因的重组卡介苗,并研究其免疫保护性.将柔嫩艾美尔球虫的ADF基因和鸡的IL-2基因串联后连接到至穿梭表达载体pMV261和整合表达载体pMV361中电转化卡介苗,制备重组卡介苗pMV261-ADF-IL-2和pMV361-ADF-IL-2,将构建的基因重组卡介苗分别以不同免疫途径接种雏鸡,研究其对柔嫩艾美耳球虫的攻毒的免疫保护效果.结果显示,成功构建重组rBCG pMV261-ADF-IL-2和pMV361-ADF-IL-2,且rBCG滴鼻免疫组的免疫效果较好,其抗球虫指数分别为176.08和172.89.结果表明,构建的基因重组卡介苗pMV261-ADF-IL-2和pMV3 61-ADF-IL-2对柔嫩艾美尔球虫卵囊的攻击具有一定的保护作用. 相似文献
88.
本研究旨在筛选新型免疫原性好、广谱的优秀 H9亚型禽流感病毒疫苗株。通过 H9N2分子流行病学调查对分离得到的37株禽流感 H9N2亚型病毒进行 HA 基因分子遗传进化及其关键位点分析,利用交叉 HI 效价及鸡胚中和试验分析毒株间毒力及其相关性,制备疫苗用毒株进行免疫攻毒保护试验。结果显示,从37株病毒中选出12株病毒作为代表,分为3个分支,同分支之间交叉 HI 效价及中和效价最高。HI 试验及鸡胚中和试验均显示同分支毒株间的相关系数高。免疫攻毒保护试验显示同分支疫苗株安全性高。表明我国禽流感 H9N2亚型情况复杂,且疫苗保护效果与疫苗株的抗原匹配性密切相关,生产多种分支 H9疫苗株联合更有利于控制 H9型禽流感, 相似文献
89.
为研究一株鸭源H9N2亚型禽流感病毒(JN1株)全基因组的分子特征和遗传进化情况以及感染雏鸭后的排毒规律,对其生物学特性、全基因组序列以及遗传进化进行了分析,通过点眼滴鼻方式感染3周龄健康雏鸭,利用建立的实时荧光定量PCR(RT-PCR)检测鸭的排毒规律,并测定血清抗体效价。JNI株的鸡胚半数感染量为10~(-7.54)/0.2mL,鸡胚最小致死量的平均死亡时间为72h,静脉致病指数为0.266,抗原相关系数为0.47。系统发育分析表明,JN1株的HA与CK/HK/G9/97和DK/HK/Y280/97在同一分支上,NA、M、NP、PA、PB1、PB2基因与SH/F/98同源性较高,NS基因则与H5N1亚型禽流感病毒进化关系较近。HA的裂解位点为PSRSSR↓GL,存在6个潜在糖基化位点,在234位的氨基酸残基为L,NA基因颈部存在缺失。雏鸭在感染该病毒后,饮食正常,精神良好,3~17d均有排毒,咽拭子和泄殖腔棉拭子排毒规律基本一致,分别在第3天和第13天出现排毒高峰。该H9N2亚型禽流感病毒属欧亚大陆分支,为低致病性禽流感,病毒可通过呼吸道和泄殖腔向外界排毒,排毒时间较长。 相似文献
90.
盐胁迫对碱茅幼苗叶片内源激素、NAD激酶及Ca2+-ATPase的效应 总被引:1,自引:3,他引:1
为了研究盐渍生境对盐生植物碱茅Puccinellia chinampoensis体内部分信号分子的影响,采用不同浓度NaCl溶液处理碱茅植株,对幼苗叶片中部分信号分子及相关蛋白测定和分析.结果发现,低盐下碱茅无胁迫反应,高盐胁迫下,碱茅脱落酸(ABA)含量升高,生长素(IAA)、赤霉素(GA)含量均下降,细胞分裂素(ZR)含量趋于稳定;碱茅NAD激酶(NADKase)活性升高,提高代谢调节能力;同时Ca2 -ATPase活性增加,是对盐胁迫引起Ca2 浓度升高而做出的胁迫反应.表明了碱茅通过胞间信号相对含量的变化,调节NADKase活性、Ca2 -ATPase活性,提高耐盐能力. 相似文献