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101.
102.
Hygienic and ecological risks connected with utilization of animal manures and biosolids in agriculture 总被引:2,自引:0,他引:2
In recent years the fate of human and animal pathogen microorganisms as a potential pollutant of the environment has been paid increased attention. Substantial quantities of these compounds and their metabolites are excreted, flushed down the drain, discarded as waste, or left over in animal feedlots. After passing to the sewer, several of these compounds are not adequately eliminated by the methods that are currently used in sewage treatment. Substantial quantities of biosolids and livestock manure end up on agricultural land. Effective sanitation of the environment, particularly of some of its special parts, which can be a source of spreading of diseases, plays an important role in prevention of infectious diseases. In this respect special attention should be paid to the disinfection of infected farm animal excrements. Sanitation of excrements should, on the one hand, ensure effective inhibition of infectious agents and, on the other hand, comply with the requirement of preserving the composition of the manure so it can be used in agricultural production. 相似文献
103.
Nadja E. Sigrist DrMedVet FVH DACVECC 《Journal of Veterinary Emergency and Critical Care》2007,17(2):117-126
Objective: To review the current understanding of dopamine and its use in the prevention and treatment of acute renal failure (ARF). Data sources: Original research articles and scientific reviews. Human data synthesis: Low‐dose dopamine administration has been shown to increase natriuresis and urinary output in both healthy individuals and in a few small studies in human patients with renal insufficiency. However, in several large meta‐analyses, dopamine treatment did not change mortality or the need for dialysis. Due to the potential side effects, the use of dopamine for prevention and treatment of ARF is no longer recommended in human medicine. Veterinary data synthesis: Low‐dose dopamine increases urinary output in healthy animals and animal models of ARF if given before the insult. There are no available studies looking at the effect of low‐dose dopamine therapy in naturally occurring ARF in dogs or cats. Conclusion: Due to the potential side effects of low‐dose dopamine therapy, the results from large human trials, and the lack of information in veterinary medicine, the use of dopamine for treatment of ARF in veterinary patients should be further evaluated. 相似文献
104.
Brajesh C. Varshney N.M. Ponnanna Pranati A. Sarkar Pragna Rehman Jigar H. Shah 《Journal of veterinary science (Suw?n-si, Korea)》2007,8(1):57-64
Escherichia coli (E. coli) strains were collected from young diarrheic calves in farms and field. Strains that expressed the K99 (F5) antigen were identified by agglutination tests using reference antibodies to K99 antigen and electron microscopy. The K99 antigen from a selected field strain (SAR-14) was heat-extracted and fractionated on a Sepharose CL-4B column. Further purification was carried out by sodium deoxycholate treatment and/or ion-exchange chromatography. Monoclonal antibodies to purified K99 antigen were produced by the hybridoma technique, and a specific clone, NEK99-5.6.12, was selected for propagation in tissue culture. The antibodies, thus obtained, were affinity-purified, characterized and coated onto Giemsa-stained Cowan-I strain of Staphylococcus aureus (S. aureus). The antibody-coated S. aureus were used in a co-agglutination test to detect K99+ E. coli isolated from feces of diarrheic calves. The specificity of the test was validated against reference monoclonal antibodies used in co-agglutination tests, as well as in ELISA. Specificity of the monoclonal antibodies was also tested against various Gram negative bacteria. The developed antibodies specifically detected purified K99 antigen in immunoblots, as well as K99+ E. coli in ELISA and co-agglutination tests. The co-agglutination test was specific and convenient for large-scale screening of K99+ E. coli isolates. 相似文献
105.
对鸡O2血清型致病性大肠杆菌1型菌毛fimI基因进行了扩增并与国外同源菌株基因序列进行了比较。结果表明:两者核苷酸同源性达98.42%,预测氨基酸顺序同源性达98.92%。fimI基因的预测氨基酸序列中仅第46位氨基酸由ALA变为THR,第76位氨基酸由SER变为ALA,其余核苷酸的变化未影响氨基酸的翻译,推测,这种改变是由分离株的差异所引起的。 相似文献
106.
以猪A组轮状病毒mRNA为模板,应用优化的反转录聚合酶链式反应(RT—PCR)技术,扩增了2331 bp的Vp4全长基因,通过T-A克隆技术,将PCR产物克隆至克隆载体pGEM-T中,构建质粒pGEM-T-Vp4。以SalⅠ和KpnⅠ双酶切pGEM—T—Vp4.和以胸苷酸合成酶基因(thymidylate synthase,thyA)为选择压力的非抗生素抗性的穿梭表达载体pW425t,并将纯化的Vp4基因亚克隆至表达载体pW425t中,构建出可以在乳酸菌与大肠杆菌之间穿梭表达的原核表达重组质粒pW425t-Vp4。将pW425t-Vp4转化至thyA基因缺陷型的大肠杆菌感受态E.coli X13中,通过生长功能弥补筛选阳性克隆,SDS-PAGE分析,可见约87.67Ku融合蛋白。Western blot分析表明,该蛋白具有与轮状病毒多克隆抗体的反应原性,研究结果为pW425t-Vp4在乳酸菌受体菌株中表达提供科学依据。 相似文献
107.
108.
鸡大肠杆菌O78对喹诺酮类药物高耐药株的分子鉴定 总被引:1,自引:0,他引:1
就临床分离的鸡大肠杆菌O78对喹诺酮类药物的最低抑菌浓度(MIC)进行了测定,得到对喹诺酮类药物有不同耐药水平的细菌23株。根据GenBank已公布的QRDRs序列,设计了分剐扩增gyrA、gyrB、parC和parE基因的4对引物,以筛选的23株耐药菌DNA为模板,进行了PCR扩增。序列分析及AcrA的Western blotting检测结果表明,临床分离的鸡大肠杆菌对喹诺酮类药物的耐药水平与GyrA和ParC的突变密切相关,而AcrAB外输泵的表达水平无显著变化。提示临床分离的鸡大肠杆菌O78的耐药水平与喹诺酮类药物的选择性压力有关,它诱导了DNA旋转酶和拓扑异构酶IV的基因突变,可能不能激活AcrAB外输泵。 相似文献
109.
我国南方猪高热病的研究(Ⅰ)——大肠杆菌的分离、鉴定和致病性测定 总被引:40,自引:2,他引:40
从湖南3个高热病发病猪场11头病死猪的病料组织中均分离出了大肠杆菌,经血清学鉴定,鞭毛抗原(K88、K99、987P和F41)全为阴性反应。经过157种菌体抗原血清学检测,血清型为5、6、15、22、32和83型。药物敏感试验结果表明,分离的大肠杆菌对大多数常用药物耐药,对氟喹诺酮和头孢类药物敏感。将其中4头猪原代分离的大肠菌培养物以原倍(2×107个/mL)、104和108稀释的菌液分别感染18~22 g小白鼠,原倍菌液感染的小白鼠12/30在感染后24 h内出现死亡,而104和108稀释菌液感染的小白鼠均健活;将未经除菌的病死猪组织悬液、过滤除菌的组织悬液、大肠杆菌、过滤除菌的组织悬液及大肠杆菌分别感染30日龄左右的健康小猪,除未经除菌的组织悬液感染猪3/3发病,2/3死亡外,其余所有感染猪只出现体温升高,升幅达1~2℃,减食,精神萎靡,但没有死亡;将死亡猪再次分离到的大肠杆菌感染小白鼠和猪,小白鼠12/15出现死亡,感染猪只出现体温升高(超过1℃),没有出现死亡。结果证明:大肠杆菌在高热病的发病过程中只起协同诱发作用,引起猪发病死亡的真正原因可能是病毒感染。 相似文献
110.
4味中药及其与抗菌药的复方制剂的MIC测定 总被引:3,自引:0,他引:3
用改进的试管两倍稀释法测定了黄连、鱼腥草、大青叶和苦参4味中药及其相互配伍(1:1)对标准大肠杆菌的最小抑菌浓度和4味中药与抗菌药配伍(1000:1)对临床分离鸡大肠杆菌的最小抑菌浓度。结果表明,4味中药及其相互配伍对大肠杆菌标准株有一定的抑制作用,其MIC值介于3.91—62.50mg/mL之间,其中大青叶和鱼腥草以1:l配伍对大肠杆菌抑菌效果最好,MIC为3.91mg/mL;对临床分离株,单方药中黄连抑菌效果最好,MIC为31.25mg/mL,24种复方药中,黄连和盐酸多西环素或加替沙星以1000:1配伍的抑菌效果最好,其MIC为3.91mg/mL。 相似文献