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41.
A cluster of Chlamydia psittaci (C. psittaci) cases was reported in Zhejiang Province, China, 2019. This study evaluates the extent of the outbreak and determines the source of infection. Real-time PCR and sequencing of the ompA gene of C. psittaci were performed to identify the cases, the domesticated poultry and close contacts. The index patient was a 76-year-old woman with chronic vertigo, and Case 2 was a 64-year-old female farmer with herpes zoster. Both women bought psittaci-infected chickens or ducks from the same mobile street vendor and raised them for 10 days and 23 days before fever onset. There were no direct contact between the two women. C. psittaci test was positive for the two patients, one sick chicken, three healthy ducks and the vendor's chicken cage. Phylogenetic analysis showed that all seven C. psittaci positive samples carried identical ompA genotype A of C. psittaci. Of all of the patients' 148 close contacts, none tested positive for C. psittaci, or developed acute respiratory symptoms. Both patients were discharged after a 4-week hospital stay. In conclusion, the source of this cluster was the poultry infected with C. psittaci, which occasionally cause infections in farmers, but inter-human transmission seems unlikely.  相似文献   
42.
This study was conducted to investigate the pattern of DNA methylation in pronuclearstage mouse embryos derived from vitrified-warmed oocytes.Mouse oocytes at metaphase Ⅱ (MⅡ) stage of meiosis were all...  相似文献   
43.
高效液相色谱法检测泰乐菌素在肉鸡组织中的残留   总被引:4,自引:0,他引:4  
将肉鸡的肌肉、肝脏、肾脏和脂肪组织制成匀浆,用乙腈、石油醚和二氯甲烷萃取、净化后,用乙腈定容。以乙腈- 甲醇- 0.005 m ol/ L磷酸二氢铵溶液(60∶30∶10)为流动相,用高效液相色谱检测。本法对溶解于乙腈中的泰乐菌素的最低检测限为 0.05 m g/ L,在肉鸡各种组织中的最低检测限为 0.10 m g/ L。标准曲线的线性范围为 0.10~6.40 m g/ L。泰乐菌素质量浓度为 0.10、0.80、6.40 m g/ L 时的批间变异系数分别为(2.3±0.2)% 、(1.9±1.3)% 、(2.6±0.9)% 。0.20、0.40、0.80 m g/ L 的泰乐菌素在以上 4 种组织的回收率均符合残留检测的要求。结果表明,本法是一种灵敏、精密、可靠的检测肉鸡组织中泰乐菌素残留的分析方法。  相似文献   
44.
35种蜂花粉的活性物质分析   总被引:5,自引:0,他引:5  
活性物质一般是指酶、维生素以及激素等,近年将磷脂也纳入活性物质。本文分析了35种蜂花粉中的葡萄糖氧化酶、磷脂以及生长激素等,这些物质对人体均有重要的生理作用。研究结果,除证明花粉中含有葡萄糖氧化酶及磷脂外,还发现了花粉含有人体生长激素  相似文献   
45.
通过对仙游县2014年秋季猪O型口蹄疫免疫抗体检测,了解和掌握仙游县猪口蹄疫免疫效果,以更好地指导今后动物疫病防控工作。  相似文献   
46.
肿瘤坏死因子α(tumor necrosis factor,TNF-α)基因在机体固有免疫和炎症反应中发挥重要作用,本研究旨在分析大白猪TNF-α基因启动子区C-791T多态性及其与基因表达之间的关系,为分析TNF-α基因启动子区C-791T突变的遗传学效应提供科学依据.本试验利用PCR-SSCP方法对201头大白猪TNF-α基因启动子区C-791T位点多态性进行检测,同时利用Real-time PCR方法分析TNF-α基因C-791T位点不同基因型在大白猪11个组织中的mRNA差异表达情况.结果表明,大白猪TNF-α基因启动子区-791 bp处存在碱基突变(C> T),并检测到3种基因型,分别为:CC、CT和TT.TNF-α基因在断奶仔猪脾脏、肺脏、胸腺和淋巴结等免疫器官中表达量均较高;TT和CT基因型个体在11个组织中TNF-α基因表达量普遍高于CC基因型个体,且在十二指肠及空肠组织中达到差异显著性水平(P <0.05).因此,TNF-α基因启动子区C-791T突变对该基因的mRNA表达水平产生显著影响,有必要将TNF-α基因启动子区C-791T位点多态性作为提升机体肠道病原菌抗性的遗传标记进行深入研究.  相似文献   
47.
随着分子遗传学的发展,已经鉴定出了影响剩余采食量(RFI)的大量数量性状位点和候选基因。有丝分裂原活化蛋白3激酶5(MAP3K5),也称凋亡信号调节激酶1(ASK1),属于MAPK超家族基因之一。目前,已有细胞外信号调节蛋白激酶(ERK)、c-Jun N-末端激酶(JNK)和p38丝裂原激活蛋白激酶(p38-MAPK)这3个MAPK家族成员在哺乳动物细胞中被克隆和鉴定,其主要作用机制是介导3条MAPKs信号通路,从而影响家畜的生长、体型及产奶性状等。课题组在前期对RFI的研究中筛选出与牛剩余采食量相关的MAP3K5基因,但其功能作用尚不明确,笔者在此基础上回顾了该基因的结构、生物学功能,概述了该基因在主要畜禽采食量变异及人类肥胖表型中的功能及作用,并从遗传学的角度重点分析了MAP3K5基因在畜禽RFI表型调控中的可能机制。通过对MAP3K5基因在畜禽RFI表型调控中的研究进展进行综述,期望为后期深入开展MAP3K5基因在畜禽采食量性状调控中的分子机制研究提供思路;对于其他可能通过MAP3K5基因影响畜禽表型的因素(如肠道菌群)有待进一步探讨。  相似文献   
48.
Peripartal cows often experience negative energy balance, and are therefore prone to suffering from metabolic diseases such as hyperketonemia, which causes financial losses in dairy farms. This study aimed to investigate the effect of green tea polyphenol (GTP) supplementation during the periparturient period on production performance, oxidative stress and immunometabolism in dairy cows with hyperketonemia. One hundred Holstein cows were assigned to GTP (0.2 g/kg DM; n = 50) or control (without GTP; n = 50) group based on body weight, previous milk yield, and parity on d 15 before expected parturition. Subsequently, 10 cows with hyperketonemia were selected from each group, according to blood β-hydroxybutyric acid (BHBA) concentration between 1.2 and 2.9 mmol/L from 2 to 3 d postpartum. All cows were fed a close-up diet and a lactation diet with or without GTP supply from 15 d prepartum until 30 d postpartum. Milk and blood samples were obtained from 20 cows selected with hyperketonemia on 10, 20, and 30 d postpartum. Compared with control cows, greater milk yield and lower somatic cell count were observed in GTP cows. The GTP group had lower concentrations of BHBA, free fatty acids, cholesterol, triglyceride, reactive oxygen species, malondialdehyde, and hydrogen peroxide, greater concentrations of glucose, lower activities of aspartate aminotransferase, alanine aminotransferase, and glutamyl transpeptidase, alongside greater activities of superoxide dismutase, glutathione peroxidase, and total antioxidant capacity. Additionally, GTP supplementation up-regulated concentrations of interleukin-6 and interleukin-10, but down-regulated concentrations of tumor necrosis factor-α, interleukin-1β, interleukin-2, interleukin-8, and interferon-γ in plasma. Greater concentrations of plasma immunoglobulin G were also detected in the GTP group. Overall, the data suggested that GTP supplementation from 15 d prepartum to 30 d postpartum improved the milk yield and health status in cows with hyperketonemia during early lactation.  相似文献   
49.
Sanguinarine (SA) and chelerythrine (CHE) are the main active components of the phytogenic livestock feed additive, Sangrovit®. However, little information is available on the pharmacokinetics of Sangrovit® in poultry. The goal of this work was to study the pharmacokinetics of SA, CHE, and their metabolites, dihydrosanguinarine (DHSA) and dihydrochelerythrine (DHCHE), in 10 healthy female broiler chickens following oral (p.o.) administration of Sangrovit® and intravenous (i.v.) administration of a mixture of SA and CHE. The plasma samples were processed using two different simple protein precipitation methods because the parent drugs and metabolites are stable under different pH conditions. The absorption and metabolism of SA following p.o. administration were fast, with half‐life (t1/2) values of 1.05 ± 0.18 hr and 0.83 ± 0.10 hr for SA and DHSA, respectively. The maximum concentration (Cmax) of DHSA (2.49 ± 1.4 μg/L) was higher that of SA (1.89 ± 0.8 μg/L). The area under the concentration vs. time curve (AUC) values for SA and DHSA were 9.92 ± 5.4 and 6.08 ± 3.49 ng/ml hr, respectively. Following i.v. administration, the clearance (CL) of SA was 6.79 ± 0.63 (L·h?1·kg?1) with a t1/2 of 0.34 ± 0.13 hr. The AUC values for DHSA and DHCHE were 7.48 ± 1.05 and 0.52 ± 0.09 (ng/ml hr), respectively. These data suggested that Sangrovit® had low absorption and bioavailability in broiler chickens. The work reported here provides useful information on the pharmacokinetic behavior of Sangrovit® after p.o. and i.v. administration in broiler chickens, which is important for the evaluation of its use in poultry.  相似文献   
50.
矮嵩草草甸植物种群物候学定量研究   总被引:10,自引:3,他引:10  
通过对矮嵩草草甸主要植物种群物候特性的观测研究,采用聚类分析和主分量排序法将矮嵩草草甸19种植物种群划分为不同的物候类群。利用相关系数排序法指出了影响不同物候期的主要生态因子依次是温度、降水量和日照时数。研究结果表明,物候指数是说明高寒矮嵩草草甸物候模式的一个有用指标。  相似文献   
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