实时荧光定量PCR检测多重耐药大肠杆菌AcrA基因mRNA表达水平

体外单一药物诱导标准大肠杆菌ATCC25922,获得了耐氯霉素（CHL,MIC≥256 mg/L）、耐环丙沙星（CIP,MIC≥256 mg/L）、耐水杨酸钠（SAL,MIC≥275 mg/L）、耐四环素（T,MIC≥512 mg/L）的菌株。选取ATCC25922株,4株中度耐药菌SAL（175）、CHL（64）、T（64）、CIP（128）,4株高度耐药菌SAL（275）、CHL（256）、T（512）、CIP（256）,和临床分离的3株耐药大肠杆菌H1、H9、H10,通过实时荧光定量RT-PCR方法检测外输泵AcrA基因的mRNA表达水平。系统自动分析软件显示,Ct值与标准质粒浓度的对数之间存在良好的线性关系,回归系数为0.992。检测结果表明：H10、CHL（256）、CIP（256）拷贝数最高,达1015拷贝/μL;T（512）、H9、T（128）、SAL（275）、H1为1014拷贝/μL;CHL（128）、T（64）、CHL（64）为1013拷贝/μL;ATCC25922为1012拷贝/μL。不同程度耐药株AcrA基因的表达量不同,临床分离株和诱导的各高耐药菌株均比ATCC25922株表达量高,且差异极显著（P≤0.01）。这说明不同耐药程度的11株菌cDNA的量存在差异,AcrA基因转录水平与耐药水平成正相关。     

高效液相色谱荧光检测法同时检测鸡血浆中阿莫西林和氨苄西林残留

建立高效液相色谱荧光法同时检测鸡血浆中阿莫西林和氨苄西林的残留量。鸡血浆经乙腈提取,饱和二氯甲烷萃取,酸性条件下水杨醛沸水浴衍生化后,以0.01mol/L的磷酸二氢钾溶液（A）和乙腈溶液（B）为流动相,梯度洗脱,流速为1.0mL/min,荧光检测激发波长为354nm,发射波长为445nm。阿莫西林和氨苄西林线性范围均为5.0~5 000.0μg/L,线性关系良好（r=0.999 9,0.999 6）。当阿莫西林和氨苄西林添加水平均为5.0~125.0mg/L时,鸡血浆样品平均回收率均高于74.72%,相对标准偏差（RSD）均低于8.65%,日内相对标准偏差分别低于4.99%和10.60%,日间相对标准偏差分别低于7.98%和11.29%。测定鸡血浆样品中AMO的检测限（LODs）为2.0μg/L（S/N=3）、定量限（LOQs）为5.0μg/L（S/N=10）,AMP的检测限为1.0μg/L（S/N=3）、定量限为2.5μg/L（S/N=10）。该方法操作简便、快速,且结果精确、灵敏、可靠,可适用于鸡血浆中阿莫西林、氨苄西林同时提取和检测。     

恩诺沙星及其代谢物在1日龄鸡体内的药动学研究

研究不同剂量恩诺沙星(ENR)及代谢产物环丙沙星(CIP)在雏鸡体内药动学特征。240只刚出壳黄羽肉鸡分2个剂量组,20 mg/kg和40 mg/kg皮下注射恩诺沙星,高效液相色谱法测定药物浓度,药时数据用WinNolin8.0软件处理非房室模型分析。结果表明,增加剂量后恩诺沙星以下药动参数发生变化:消除半衰期(t_(1/2))由7.37 h降至6.53 h,达峰时间(T_(max))由8 h降到4 h,最大血药浓度(C_(max))由3.75μg/mL增至4.92μg/mL,药时曲线下面积(AUC_(last))由40.45 h·μg/mL增至78.2 h·μg/mL,平均滞留时间(MRT_(last))由为8.6 h增至11.42 h;消除率(Cl)分别为0.49 L/h/kg和0.5 L/h/kg,表观分布容积(Vz_(obs))分别为5.22 L/kg和4.77 L/kg。不同剂量恩诺沙星给药后都都表现出分布迅速、广泛的特点,代谢产物环丙沙星产生与消除迅速。     

环丙沙星对实验性猪支原体性肺炎的药效学研究

测定环丙沙星及对照药物对猪肺炎支原体的最小抑菌浓度，其中环丙沙星的抗支原体活性最强，最小抑菌浓度为0．01μg/ml。通过给18头健康猪气管内接种含有猪肺炎支原体的病肺悬液，复制具有典型症状的猪支原体性肺炎疾病模型，并进行环丙沙星2．5、5．0mg/kg肌注给药对实验性猪支原体性肺炎的疗效实验及血浆药物浓度监测，两组治愈率分别为83．3％（5／6）和100％（6／6）。治疗组多剂量给药期间，第1、3、5、7、9次给药后0．5及6h的血浆药物浓度，在2．5mg/kg剂量组平均为0．41μg/ml和0．17μg/ml,5.0mg/kg剂量组平均为0．71μg/ml和0．28μg/ml。两剂量组环丙沙星均无蓄积作用。     

高效液相色谱法同时测定猪血浆中的SMM、SMZ和TMP

建立同时测定SMM，SMZ和TMP血药浓度的HPLC方法，采用WatersHPLC系统，Wa-tersODS2柱，以乙腈：0.017mol/L磷酸液(20：80）为流动相，检测波长为230nm,SMM,SMZ在0.05-10.0μg/ml范围内线性良好（r=0.99998),TMP在0.01-2.0μg/ml范围内线性良好（r=0.99999)，平均方法回收率分别为94.5%,98.6%和86.8%。最低血浆检测浓度可达SMM0.15μ/ml，SMZ，0.15μ/ml，TMP0.03μg/ml。该法采血量少，样品预处理简单，检测快速，灵敏。     

用于检测牛奶中噻苯咪唑ELISA检测试剂盒的研制

在噻苯咪唑(TBZ)单克隆抗体制备基础上,建立间接竞争酶联免疫吸附法(ELISA)并组装试剂盒。结果表明,试剂盒标准曲线的线性范围为1.0⁸1.0μg/L,回归方程为Y=-2.104 8x+1.038 2(R2=0.999 8),抗体对TBZ 50%的抑制浓度为4.3μg/L;对牛奶中TBZ的最低检测限为40μg/L,牛奶样品的加标回收率范围在75.8%81.0μg/L,回归方程为Y=-2.104 8x+1.038 2(R2=0.999 8),抗体对TBZ 50%的抑制浓度为4.3μg/L;对牛奶中TBZ的最低检测限为40μg/L,牛奶样品的加标回收率范围在75.8%¹04.8%,批内变异系数范围为6.4%104.8%,批内变异系数范围为6.4%¹1.9%,批间变异系数范围为8.2%11.9%,批间变异系数范围为8.2%¹0.0%;TBZ试剂盒(TBZ-Kit)对TBZ特异性良好,并可在210.0%;TBZ试剂盒(TBZ-Kit)对TBZ特异性良好,并可在2⁸℃条件下保存至少360 d。该试剂盒各项指标符合相关技术要求,具有快速、灵敏、专一、稳定的特点。     

环丙沙星完全抗原的制备和间接竞争ELISA检测方法的初步研究

为了研究检测环丙沙星(CIP)残留的间接竞争ELISA方法,试验采用1-乙基-3-(3-二甲基氨基丙基)碳化二亚胺盐酸盐(EDC)一步法将环丙沙星分别与牛血清白蛋白(BSA)和鸡卵清白蛋白(OVA)偶联制备免疫原(CIP-BSA)和包被原(CIP-OVA),用免疫原免疫Balb/c小鼠制备血清多克隆抗体(CIP pAb...     

氯霉素残留检测阻断ELISA试剂盒的研制及性能测定

在建立氯霉素单克隆抗体（CAP mAb）杂交瘤细胞株和阻断ELISA方法的基础上．研制出CAP残留快速检测试剂盒（CAP-kit），并对其性能进行了测定。结果表明，CAP-kit的标准曲线呈典型的S型，符合4参数logit曲线拟合，相关系数R^2=0．9953，检测范围为1．0μg/L～128．0μg/L，灵敏度为0．85μg／L，半数抑制浓度（IC50）为7．54μg/L，检测限为1．0μg/L；牛奶样、猪肉样的平均添加回收率为88．3％、82．5％，平均批内和批间变异系数均〈15％；CAP-kit与氯霉素琥珀酸钠的交叉反应（CR％）为150％，与其它酰胺醇类和抗菌素药物无交叉反应；试剂盒在4℃可保存6个月。     

气相色谱－质谱法测定猪尿中莱克多巴胺

建立了猪尿中莱克多巴胺的气相色谱-质谱（GC-MS）检测方法。样品经β-盐酸葡萄糖醛苷酶/芳基硫酸酯酶水解,乙酸乙酯提取、盐酸溶液萃取,SCX固相萃取柱净化,N,O-双三甲基硅基-三氟乙酰胺（BSTFA）衍生化后进行气相色谱-质谱测定。结果表明,方法检出限为0.3μg/L,定量限为0.5μg/L,线性范围为10-500μg/L。在2、4、8μg/L三个添加浓度水平上,莱克多巴胺的平均回收率为85%-115%,批内、批间相对标准偏差均小于10%。     

大田软海绵酸单克隆抗体ELISA检测方法的建立

利用BALB／c小鼠腹水大量制备抗大田软海绵酸（okadaic acid，OA）的单克隆抗体，并以此抗体为探针建立了0A的快速、灵敏、简便的ELISA检测方法——直接和间接竞争抑制性ELISA方法，2种检测方法的回归方程和相关系数分别为：y=-38．678χ＋130．01，R^2=0．9886和y=-34．212x＋83．49，R^2=0．9784，线性范围为1.56～75μg／L和0.4425μg／L，对OA的最低检出质量浓度为0．6μg／L和0．18μg／L。并利用所建立的2种ELISA方法对贝类模拟样品及实际样品进行了检测，样品回收率分别为84．72％和98．38％。结果表明，此方法可满足海产品中贝类样品0A限量标准检测。     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Changes in proportion of canine urinary calculi composed of calcium oxalate or struvite in specimens analyzed from 1981 through 2001

The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.     

Smart Phone Assisted City-scale Wireless Sensor Network Deployment for Transportation System Monitoring

<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.