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981.
E.coli K1 strain is a representative strain of neonatal sepsis and meningitis, which causes disease by blood circulation to the brain. The molecular mechanism of E.coli K1 that adhering and invading the brain microvascular endothelial cells (BMECs) and cross the blood brain barrier (BBB) has been focused on by many scholars. In this review, we focused on the gene regulation mechanisms and signaling pathway of E.coli K1 crossing the blood brain barrier to understand the molecular mechanism of the infection caused by E.coli and provide reference for prevention and treatment programs.  相似文献   
982.
通过分析我国出口肠衣受阻原因,以及国际肠衣技术要求、中欧(中国及欧盟)肠衣安全限量发现:欧盟肠衣技术壁垒越来越严格,涉及范围扩大,影响面广,具有明显的贸易保护特征和连锁扩散效应;我国技术性贸易保护体系存在生产基础弱、标准体系技术性差、行业协会作用不明显、出口企业应对能力不足,以及与欧盟的贸易保护实力不对等问题。需要构筑三位一体的战略应对体系:政府负责政策制定、谈判和组织管理工作,行业协会发挥标准制定、行业预警和中介协调作用,出口生产企业承担主体责任。同时,监管部门还需加强监管,逐步健全和提高市场准入标准。  相似文献   
983.
Follicular cysts, which is a common infertility disease, can cause financial losses in pig breeding programmes. The pathogenesis and mechanisms of the formation of follicular cysts are not understood clearly. In our previous study, the concentration of retinol‐binding protein 4 (RBP‐4) in the follicular fluid (FF) of the ovary with follicular cysts was found to be significantly higher than that of normal ovary, thereby suggesting that RBP‐4 may be a candidate biomarker for porcine follicular cysts. To study the association of RBP‐4 and follicular cysts further, we detected the polymorphisms of the RBP‐4 gene and the presence of follicular cysts by PCR‐Restriction fragment length polymorphism (RFLP) assay. In this study, we screened the mutations of RBP‐4 gene in 79 sows with follicular cysts and 100 normal sows without cysts. Results showed that +249‐63G>C polymorphisms were significantly associated with follicular cysts, and sows with CC genotype in RBP‐4 gene had a high risk of developing follicular cysts. Hence, our findings further proved that RBP‐4 may be a novel biomarker for follicular cysts, which may be valuable for the diagnosis of follicular cysts and molecular breeding of pigs.  相似文献   
984.
犬严重子宫蓄脓的影象学诊断   总被引:1,自引:0,他引:1  
子宫蓄脓本为犬多发的常见病,诊断并不困难。最近我们收治1例特别严重的子宫蓄脓,诊断一时难以明确,经综合影象学检查后,方得以确定,报告如下。1 病史华南农业大学动物医学系动物医院收治1例本地母犬,7岁,从未配种怀孕。因不食、腹围渐胀大而求诊,临床疑为腹水症,两天前  收稿日期:19981127抽出过少量液体。2 体格检查病犬精神差,躺卧不能站立和运动,稍消瘦和贫血,厌食已20余天,每天只饮水,无大便,尿量正常;心跳快而心音弱,脉搏150次/min,呼吸56次/min,体温392℃。就诊时饮水…  相似文献   
985.
mRNA差异显示技术是近年来国外发展起来的攻克隆新基因的一种新方法,同时已广泛用于人类基因调控和克隆研究。本文论述了这一新技术的原理、发展现状和在动物遗传育种中的应用领域。  相似文献   
986.
短周期间歇光照对肉用仔鸡生产性能的影响   总被引:2,自引:0,他引:2  
在7日龄时,肉服仔鸡由接近全日制光照改变为1h光照,3h黑暗的短周期简歇光照。结果表明,短周期间歇光照的肉仔鸡饲料报酬和饲料利用率提高,氮平衡试验表明,增加肉用仔鸡的光周期,粪氮分泌量减少,饲料氮在鸡体内的沉积增加,而饲料氮的摄入量并未增加,因而使得饲料氮的利用率和到提高。  相似文献   
987.
试验结果表明,埋植“玉米赤霉醇”的山羊平均日增重比放牧组提高118.4%,差异极显著(P〈0.01),比补料组提高15.3%,差异显著(P〈0.05),且增肉剂组的屠宰率也有所提高,同时杂种羊比地方山羊增重效果好,增肉剂组中南本F1的平均日增重比地方山羊提高17.1%,应用增肉剂后经济效益明显,投入产出比为1:3.5,值得推广应用。  相似文献   
988.
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   
989.
新冠病毒感染给人类带来了巨大灾难,也给动物带来严重影响。全球已有36个国家报告至少26种哺乳动物感染新冠病毒(SARS-CoV-2),包括宠物、养殖动物和野生动物。绝大部分动物的SARS-CoV-2感染来自与人类接触,感染后无明显症状或症状轻微。宠物中,犬和猫对SARS-CoV-2具有一定的易感性,其感染率与宠物主人的密切接触程度有关,但总体感染率不高,目前还没有宠物在人类感染传播中起重要作用的证据。养殖动物和野生动物中,水貂和白尾鹿极易感染SARS-CoV-2,种群感染率很高,而且在其体内病毒可以快速变异和进化,甚至回传感染人类;水貂是动物中SARS-CoV-2感染最严重的宿主,感染后表现严重的临床症状甚至死亡。目前尚无动物SARS-CoV-2感染对人类健康、动物健康以及生物多样性产生重大影响的证据,但动物感染不仅会影响动物种群的健康,而且可能造成SARS-CoV-2变异株的出现,进而威胁人类健康。因此,需要坚持“同一健康”理念,加强对动物SARS-CoV-2感染的监测和防控。  相似文献   
990.
This experiment was conducted to investigate the effects of dietary Ampitheoe sp. powder on the growth and the contents of astaxanthin, triglyceride (TG), total cholesterol (TCHO) and fatty acids of Litopenaeus vannamei. A total of approximately 6 777 L. vannamei with an initial body weight of (1. 80 ± 0.72) g were randomly divided into 3 groups, and there were 3 replicates (753 shrimp per replicate) in each group. Those shrimp fed diets containing 0 (D0 group), 8. 25% (D8. 25 group) and 33% (D33. 00 group) Ampitheoe sp. powder, respectively. The feeding trial lasted for 40 days. The results showed as follows: 1) the final body weight, weight gain rate, specific growth rate, yield and survival rate in D33.00 group were significantly higher than those in D0 group (P <0.05), whereas the feed conversion ratio was significantly lower than that in D0 group (P <0.05) . However, there was no significant difference between D33.00 group and the D8. 25 group in those indexes (P >0.05) . 2) The astaxanthin content in carapace, hepatopancreas and muscle of L. vannamei in D8.25 and D33. 00 groups was significantly higher than that in D0 group (P < 0. 05); that in D33.00 group was significantly higher than that in D8. 25 group (P < 0. 05) . 3) TG content in haemolymph, hepatopancreas and muscle in D8. 25 and D33. 00 groups was significantly lower than that in D0 group (P < 0.05); the TCHO content in hepatopancreas in D8. 25 group was significantly higher than that in D0 and D33.00 groups (P <0.05); TCHO content in muscle in D33.00 group was significantly higher than that in D0 group (P <0.05) . 4) The contents of eicosapentaenoic acid (EPA) and arachidonic acid (AA) in hepatopancreas in D33.00 group were significantly higher than those in D0 group (P <0.05) . The EPA content in muscle in D33.00 group was significantly higher than that in D0 group (P < 0. 05) . In conclusion, adding Ampitheoe sp. powder into the diet can improve the growth performance, the contents of astaxanthin, EPA and AA in L. vannamei, and affect the accumulation of TG and TCHO, which can be used as a functional diet in aquaculture. Considering the cost, the supplementation level of 8. 25% Ampitheoe sp. powder is more appropriate. © 2023 Chinese Journal of Pediatric Surgery. All rights reserved.  相似文献   
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