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181.
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183.
黏菌素是目前临床治疗多重耐药革兰阴性菌感染的重要药物之一,mcr-1基因的携带可介导黏菌素耐药性的产生和扩散。鸡源沙门氏菌作为重要的食源性病原菌,其血清型分布、对黏菌素的耐药性及mcr-1基因的携带对于公共卫生安全具有重要意义。研究对2014-2016年从全国12个省份成鸡分离的450株沙门氏菌进行了血清分型;用微量肉汤稀释法进行了对黏菌素的MIC检测;并用PCR方法对mcr-1基因的携带情况进行了调查。结果表明,鸡源沙门氏菌的优势血清型以肠炎、鸡白痢和鼠伤寒为主;肠炎沙门氏菌对黏菌素的耐药性最强(62.9%),其次为鸡白痢(50.5%)和杜伊斯堡(38.1%);鼠伤寒沙门氏菌对黏菌素最敏感(仅7.1%的菌株耐药);未检测出mcr-1基因阳性的沙门氏菌。研究结果为鸡源沙门氏菌感染的防控以及兽医临床黏菌素的使用和风险评估提供了技术参考。 相似文献
184.
猪传染性胸膜肺炎放线杆菌的鉴定和耐药性研究 总被引:1,自引:0,他引:1
猪传染性胸膜肺炎是由猪传染性胸膜肺炎放线杆菌(Actinobacillus pleuralpneumoniae,APP)引起的一种高度传染性呼吸道疾病,临床上准确鉴定该病原菌并合理选择抗生素施药十分重要。研究比较了应用传统方法、PCR方法和MALDI TOF方法鉴定45株临床APP,并比较了三种优势血清型的毒力表型,最后测定了其对临床34种常见抗生素的MIC。结果发现MALDI TOF微生物学鉴定方法具有快速、准确的优势;临床菌株血清型主要包括3型(20株)、1型(13株)、7型(7株),其他血清型菌株5株,其中1型毒力最强;APP对罗红霉素、头孢噻呋、恩诺沙星、氨苄西林等高度敏感,对四环素、土霉素等耐药率较高。研究为临床快速鉴定APP和合理选择用药提供了参考依据,为APP临床耐药折点的制定奠定了基础。 相似文献
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186.
蛋白多肽二级结构的电脑预测表明,非洲猪瘟病毒k8R基因编码带有多个疏水氨基酸小区的27kDa蛋白质。该基因的PCR产物克隆入质粒pGEX-2T后,在大肠杆菌中表达42-54kDa不溶性GST-k8R融合蛋白。此表达蛋白能被针对不同非洲猪瘟病毒侏的猪免疫血清识别。 相似文献
187.
Fokialakis N Osbrink WL Mamonov LK Gemejieva NG Mims AB Skaltsounis AL Lax AR Cantrell CL 《Pest management science》2006,62(9):832-838
Over 220 crude extracts from repositories generated from plants native to Greece and Kazakhstan were evaluated for termiticidal activity against the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae). Emerging from this screening effort were bioactive extracts from two Greek species (Echinops ritro L. and Echinops spinosissimus Turra subsp. spinosissimus) and extracts from two Kazakhstan species (Echinops albicaulis Kar. & Kir. and Echinops transiliensis Golosh.). Fractionation and isolation of constituents from the most active extracts from each of the four species has been completed, resulting in the isolation of eight thiophenes possessing varying degrees of termiticidal activity. 2,2':5',2"-Terthiophene and 5'-(3-buten-1-ynyl)-2,2'-bithiophene demonstrated 100% mortality against C. formosanus within 9 days at 1 and 2 wt% concentrations respectively. In addition, all but two of the eight compounds tested were significantly different from the solvent controls in the filter paper consumption bioassay. 相似文献
188.
为研究自制盐酸多西环素注射液在猪体内的药代动力学-药效学,对10头健康猪单次肌内注射盐酸多西环素注射液,采用UPLC法测定血浆中药物浓度,利用药代动力学软件WinNonlin进行数据处理。结果显示,主要药代动力学参数:消除半衰期t1/2为(31.3±9.2)h,达峰时间Tmax为(0.80±0.7)h,峰浓度Cmax为(4132±2475)μg/L,药时曲线下面积AUC为(88378±88095)(μg/L)·h,平均滞留时间MRT为(20.5±2.5)h;PK/PD参数T〉MIC为24h,AUC/MIC〉50。试验表明该制剂以10mg/kg剂量肌内注射,给药间隔两天一次为宜。 相似文献
189.
Folador JF Karr-Lilienthal LK Parsons CM Bauer LL Utterback PL Schasteen CS Bechtel PJ Fahey GC 《Journal of animal science》2006,84(10):2752-2765
An experiment to determine the chemical composition and protein quality of 13 fish substrates (pollock by-products, n = 5; fish protein hydrolysates, n = 5; and fish meals, n = 3) was conducted. Two of these substrates, salmon protein hydrolysate (SPH) and salmon meal with crushed bones (SMB), were used to determine their palatability as components of dog diets. Pollock by-products differed in concentrations of CP, crude fat, and total AA by 71, 79, and 71%, respectively, and GE by 4.1 kcal/g. Fish protein hydrolysates and fish meals were less variable (approximately 18, 14, and 17%, and 1.4 kcal/g, respectively). Biogenic amine concentrations were much higher in fish protein hydrolysates as compared with pollock by-products and fish meals. Pollock liver and viscera had the highest total fatty acid concentrations; however, red salmon hydrolysate and SMB had the highest total PUFA concentrations (49.63 and 48.60 mg/g, respectively). Salmon protein hydrolysate had the highest protein solubility in 0.2% KOH. Based on calculations using immobilized digestive enzyme assay values, lysine digestibility of fish meal substrates was comparable to in vivo cecectomized rooster assay values and averaged approximately 90.3%. Also, pollock milt, pollock viscera, red salmon hydrolysate, and sole hydrolysate had comparable values as assessed by immobilized digestive enzyme assay and rooster assays. A chick protein efficiency ratio (PER) assay compared SMB and SPH to a whole egg meal control and showed that SMB had high protein quality (PER = 3.5), whereas SPH had poor protein quality (PER value less than 1.5). However, using whole egg meal as the reference protein, both fish substrates were found to be good protein sources with an essential AA index of 1.0 and 0.9 for SMB and SPH, respectively. In the dog palatability experiments, a chicken-based control diet and 2 diets containing 10% of either SPH or SMB were tested. Dogs consumed more of the SPH diet compared with the control, and similar amounts of the SMB and control diets. The intake ratios for each were 0.73 and 0.52, respectively. Salmon protein hydrolysate was especially palatable to dogs. These data suggest that chemical composition and nutritional quality of fish substrates differ greatly and are affected by the specific part of the fish used to prepare fish meals and fish protein hydrolysates. 相似文献
190.
The purpose of this study was to develop a multiplex polymerase chain reaction (PCR) protocol useful in the virulence genotyping of Salmonella spp. with the idea that genotyping could augment current Salmonella characterization and typing methods. Seventeen genes associated with Salmonella invasion, fimbrial production, toxin production, iron transport, and intramacrophage survival were targeted by three PCR reactions. Most of these genes are required for full Salmonella virulence in a murine model, and many are also located on Salmonella pathogenicity islands (PAIs) and are associated with type III secretion systems (TTSSs). Once the success of procedures that used positive and negative control strains was verified, the genotypes of 78 Salmonella isolates incriminated in avian salmonellosis (primarily from sick, commercially reared chickens and turkeys) and 80 Salmonella isolates from apparently healthy chickens or turkeys were compared. Eleven of the 17 genes tested (invA, orgA, prgH, tolC, spaN [invJ], sipB, sitC, pagC, msgA, spiA, and iroN) were found in all of the isolates. Another (sopB) was present in all isolates from sick birds and all but one isolate from healthy birds. The remaining five genes (lpfC, cdtB, sifA, pefA, and spvB) were found in 10%-90% of the isolates from sick birds and 3.75%-90% of the healthy birds. No significant differences in the occurrence of these genes between the two groups of isolates were detected. These results suggest that these virulence genes, and presumably the PAls and TTSSs with which they are associated, are widely distributed among Salmonella isolates of birds, regardless of whether their hosts of origin have been identified as having salmonellosis. 相似文献