首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
建立了动物源食品中氯霉素、甲砜霉素、氟苯尼考及氟苯尼考胺残留检测的超高效液相色谱-串联质谱(UPLC-MS/MS)分析方法.样品在碱性条件下用乙酸乙酯提取后,再用正己烷去除脂肪,浓缩后用BEH C18(50 mm×2.1 mm,1.7 μm)色谱柱分离,以乙腈和水为流动相进行梯度洗脱,流速为0.3 mL/min,多反应监测(MRM)模式检测.结果表明:四种药物在2~500 μg/L的系列浓度范围内均呈良好线性关系,相关系数r均大于0.990.样品中氯霉素的检测限为0.1 μg/kg,定量限为0.2 μg/kg;甲砜霉素、氟苯尼考和氟苯尼考胺的检测限为0.5 μg/kg,定量限为1 μg/kg.本方法氯霉素在0.2~1 μg/kg的添加浓度范围内,甲砜霉素、氟苯尼考及氟苯尼考胺在1~50 μg/kg的添加浓度范围内平均回收率均为70%~120%,相对标准偏差(RSD)均小于20%.该方法具有简便快捷、灵敏度高、定性准确等特点.  相似文献   

2.
建立了猪肝组织中氯霉素残留检测的高效液相色谱-串联质谱(LC-MS/MS)法.液相色谱条件为色谱柱为Alltech Altima C18柱(150 mm×3.2 mm,5 μm);流动相为甲醇-水(1∶ 1,V/V);柱温为30 ℃;流速为0.3 mL/min;进样量为20 μL.质谱条件为电喷雾离子源(ESI-),多反应离子监测(MRM)方式进行采集;监测离子质荷比为320.60>52.20,320.60>194.15.以氯霉素的同分异构体间位氯霉素作内标,内标法定量.结果表明,氯霉素的线性范围为0.5~10 ng/mL,相关系数R2=0.999 9;方法检测限为0.1 μg/kg,定量限为0.2 μg/kg;从0.1、0.2、0.4和1.0 μg/kg四个添加浓度检测结果可以看出,方法的平均回收率为96.6%~116.6%(n=6),批内批间RSD均小于20%.  相似文献   

3.
酶联免疫法测定鸡肝中氯霉素残留   总被引:7,自引:2,他引:7  
运用酶联免疫检测试剂盒测定鸡肝中氯霉素的残留量.氯霉素标准液浓度在 0.025~2 μg/mL范围内线性良好,r=0.995 1,鸡肝中最低检测限为0.10 μg/kg.空白添加阳性样品浓度为0.1、0.5和1.0 μg/kg时,回收率分别为86.9%、89.1%和80.0%,板内变异系数<14.6%,板间变异系数<12.0%;本方法操作简单快捷、灵敏准确、方便实用,可作为鸡肝中氯霉素残留检测的快速筛选方法.  相似文献   

4.
建立一种高效液相色谱-串联质谱法快速测定婴幼儿乳粉中氯霉素残留的方法。样品以D5-氯霉素为内标,碱化后,经乙酸乙酯提取、低温离心、氮吹浓缩,流动相复溶,采用高效液相色谱-串联质谱法测定。结果表明:在0.1~5μg/L范围内氯霉素呈良好的线性关系,高、中、低浓度回收率为80%~110%,精密度小于15%,定量限为0.1μg/kg。本方法快速、简便,适于乳粉中氯霉素残留的快速测定。  相似文献   

5.
鸡蛋中氯霉素残留的检测方法及其消除规律   总被引:5,自引:0,他引:5  
选用处于产蛋高峰期的健康海兰蛋鸡20只,单笼饲养,多剂量内服氯霉素(每千克体质量100 mg,连喂12 d),停药后逐只逐日收集鸡蛋,将蛋白、蛋黄分别匀浆,用乙腈、乙酸乙酯、正己烷萃取及净化后,HPLC检测氯霉素浓度.色谱柱为Waters Nova-Pak C18(3.9 mm×150 mm)柱,检测波长为280 nm,流动相为乙腈/水(20/80),流速为1 mL/min,进样量为50 μL.在上述条件下,氯霉素的色谱峰保留时间约为8.0 min,最低检测限为0.002 μg/g,标准曲线的线性范围为0.002~20 μg/g.氯霉素含量为0.5 μg/g时,在蛋白中的批内、批间变异系数分别为3.52%、3.43%;在蛋黄中的批内、批间变异系数分别为3.83%、3.37%.将氯霉素以0.5 μg/g分别添加到空白蛋白和蛋黄中,测得蛋白、蛋黄中氯霉素的回收率分别为94.89%、83.15%.结果表明,本法是一种简便、灵敏、可靠的检测鸡蛋中氯霉素残留的分析方法.停药当天,蛋白、蛋黄中的氯霉素分别为3.61、14.51 μg/g;停药第5天,分别为0.05、7.17 μg/g;停药第8天,蛋白中已检测不到氯霉素,蛋黄中氯霉素为0.80 μg/g;停药第11天,蛋黄中尚有0.04 μg/g的氯霉素,而停药第12天,蛋黄中已检测不到氯霉素.采用MCPKP药动学参数计算程序处理药时数据,算出蛋白、蛋黄中的消除半衰期分别为0.75、1.64 d.结果表明,氯霉素多分布于蛋黄,在蛋黄中的残留水平高,且在蛋黄中的消除较蛋白缓慢.  相似文献   

6.
建立了快速测定禽蛋中氯霉素、氟苯尼考及氟苯尼考胺的超高效液相色谱-串联质谱分析方法。禽蛋用乙腈提取后,再用正己烷液液分配除脂,浓缩后用超高效液相色谱分离,以乙腈和10%甲醇水为流动相进行梯度洗脱,MRM反应监测模式检测。结果表明在5-200μg/L的系列浓度范围内均呈良好线性关系,相关系数均大于0.999。氯霉素、氟苯尼考、氟苯尼考胺的检测限为0.5μg/kg,定量限为2.0 μg/kg,本方法在2μg/kg~20μg/kg添加浓度范围内平均回收率为60%~100%,精密度小于20%。该方法方便快捷、定性准确适于禽蛋中的氯霉素、氟苯尼考及氟苯尼考胺药物残留检测。  相似文献   

7.
建立了检测猪尿中7种α2-受体激动剂的超高效液相色谱-串联质谱分析方法。试样经调节pH,乙酸乙酯提取并浓缩、净化后,经液相色谱-串联质谱测定,外标法定量。结果表明,7种α2-受体激动剂在1~80μg /L浓度范围内均呈良好线性关系,相关系数均大于0.99。7种目标化合物检测限为0.1 μg /L,定量限为0.3 μg /L。在1~20 μg /kg添加浓度范围内回收率为60%~110%,相对标准偏差小于15%。该方法方便快捷,定性准确,可为猪尿中该类兽药残留的日常监控提供方便、快捷的检测方法支持。  相似文献   

8.
建立超高效液相色谱-串联质谱法(UPLC-MS/MS)测定牛奶中11种激素类药物残留的检测方法。样品经乙酸乙酯提取,氮气吹干,残留物用0.1 %甲酸50 %乙腈水溶液溶解后,经Cleaner MAS-Q 净化管净化,滤膜过滤后用超高效液相色谱-串联质谱仪测定,基质外标法定量。在0.5~100 ng/mL的浓度范围内11中激素类药物峰面积与浓度呈良好的线性相关,相关系数均大于0.998;方法的定量限为1.0 μg/kg;牛奶样品中11种激素类药物在1.0~10 μg/kg添加水平内的平均回收率在60.3 %~119.6 % 之间,批内、批间相对标准偏差在0.2 %~12.1 %之间。该方法灵敏、准确、重现性良好,能够满足残留检测要求。  相似文献   

9.
[摘 要] 建立了虾肌肉中氟苯尼考和氟苯尼考胺残留的高效液相色谱检测法。以水和丙酮为提取溶液,Oasis MCX固相萃取柱净化,采用Inertsil ODS-3(5μm , 250mm×4.6mm i.d.)反相色谱柱,以比例为68:32的A液(0.02 mol/L戊烷磺酸钠—0.025 mol/L磷酸钠溶液,pH 3.85)与B液(含0.1%三乙胺的甲醇溶液)为流动相,在225nm处检测。氟苯尼考和氟苯尼考胺在10~1000 µg/kg浓度范围内,线性关系良好;添加浓度为50、100、200、500 μg/kg时,回收率在75.8%~85.9%,日内变异系数在 2.4%~4.5%,日间变异系数在 4.0%~5.8%;方法的检测限为10 μg/kg,定量限为30 μg/kg。本方法灵敏、准确、简便、快速,适于虾肌肉中氟苯尼考和氟苯尼考胺残留的同时检测。  相似文献   

10.
牛奶中氨苄青霉素残留测方法研究   总被引:11,自引:0,他引:11  
用三氯乙酸溶液沉淀牛奶蛋白并提取氨苄青霉素残留,在酸性条件下,提取液中的氨苄青霉素与甲醛加热生成2-羟基-3-苯基-6-甲基吡嗪(氨苄青霉素荧光衍生物),用带有荧光检测器的高效液相色谱仪在激发波长(Ex)346 nm、发射波长(Em)420 nm条件下测定该衍生物,外标法定量.本方法简单、快速、灵敏度高,最低检测限为1 μg/L,最低定量限为2 μg/L,回收率为70%~110%,批内变异系数在1 0%以内,批间变异系数小于1 5%.  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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。  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

17.
18.
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.  相似文献   

19.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

20.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号