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1.
利用超高效液相色谱-高分辨四极杆飞行时间质谱对预混剂中的黄霉素5种组分进行鉴别分析。采用C18色谱柱分离,以乙腈-0.1%甲酸水溶液(含2 mmol/L乙酸铵)为流动相梯度洗脱,流速0.4 m L/min,柱温40℃;质谱条件为电喷雾离子源,检测方式为负离子全扫描模式,通过保留时间、精确分子量和二级质谱特征碎片完成对黄霉素的5种组分的鉴别。与高效液相色谱方法比较,本方法具有判断准确、检测快速的特点,具有很好的应用价值。  相似文献   

2.
建立了基于超高效液相色谱-四级杆-静电场轨道阱高分辨质谱联用(UPLC-Q-Exactive Orbitrap)快速筛查和确证定量饲料中16种硝基咪唑类药物的分析方法。饲料样品经含0.1%甲酸的乙腈-水(80:20,V/V)溶液震荡提取,Waters ACQUITY UPLC○R BEH C18色谱柱(2.1mm×100mm,1.7μm)分离,以(含0.1%甲酸)乙腈-甲醇(50:50,V/V)溶液和(含0.1%甲酸)水溶液为流动相进行梯度洗脱。静电场轨道阱全扫描得到16种硝基咪唑类药物的一级精确质量数与理论精确质量数对比,质量偏差在0.04975~0.93988mDa;同时建立了二级质谱数据库,实现对16种硝基咪唑类药物的定性筛查及同步定量。16种硝基咪唑类药物在0.1~200μg/L浓度范围内线性关系良好r>0.9990,方法检测限在25μg/Kg^100μg/Kg,回收率在49.47%~105.4%。  相似文献   

3.
本文建立了水产品中10种大环内酯类抗生素的高效液相色谱-电喷雾串联质谱检测方法。对比几种检测方法后,最终采用乙腈进行提取的方法。在5.0～200.0μg/L范围内,10种大环内酯类抗生素的线性相关系数均大于0.99。通过实际样品的添加回收试验,方法的定量下限(S/N=10)为1.0μg/kg,检出限(S/N=3)为0.2μg/kg,3个添加水平中,龙虾、鮰鱼的加标回收率分别为69.4%～115.3%和63.1%～100.9%,日内相对标准偏差(RSD)分别为0.73%～3.39%及0.8%～4.44%。结果表明,该法简单、灵敏、特异性强,适用于水产品中大环内酯类药物残留的分析确证。  相似文献   

4.
建立了超高效液相色谱-四级杆-静电场轨道阱高分辨质谱联用(UPLC-Q-Exactive Orbitrap)快速筛查和确证定量饲料中19种磺胺类药物的分析方法。饲料样品经乙腈-0.1%甲酸溶液(80:20,V/V)超声提取,Agilent SB C18色谱柱(100 mm×3.0 mm,1.8μm)分离,以0.1%(V/V)甲酸乙腈溶液和0.1%(V/V)甲酸水溶液为流动相进行梯度洗脱。静电场轨道阱全扫描得到磺胺类药物的一级精确质量数与理论精确相对分子质量对比,相对质量偏差在0.006×10-6~1.252×10-6之间,有效去除了基质干扰,实现对饲料中磺胺类药物的快速筛查;同时建立了19种磺胺类药物的二级质谱数据库,实现对19种磺胺类药物的定性筛查及同步定量。19种磺胺类药物在0.1~200μg/L浓度范围内线性关系良好r0.99,方法检测限为50μg/kg,回收率在59.61%~106.45%之间。  相似文献   

5.
建立了超高效液相色谱-静电轨道阱质谱法检测饲料中的51种农药残留物的检测方法和目标化合物的质谱数据库。饲料样品经0.1 mol/mL HCl : 甲醇=1:3提取,高速离心,经稀释后进样分析。采用Thermo Syncronis C18色谱柱(150 mm×2.1 mm, 3 μm)作为固定相,0.1 %甲酸和0.1%甲酸乙腈作为流动相进行梯度洗脱。质谱采用正负切换离子扫描,一对母离子和子离子的精确质量数进行定性,以母离子的响应强度积分面积进行定量分析。51种农药残留化合物在最优化条件下分离良好,在定量范围内均线性良好(线性相关系数r≥0.99),回收率也可达到50.61 ％～ 109.49 % ,相对标准偏差(RSD)小于9.1 %。本方法具有简便、快速、灵敏、准确等特点,适用于饲料中同时筛查和定量农药残留化合物。  相似文献   

6.
采用UPLC-PDA联合UPLC-MS/MS方法确证了一批标称杨树花口服液中非法添加物甘草酸。样品经提取稀释后，采用ACQUITY UPLC T3色谱柱为分离柱，UPLC-PDA初步筛查，再用负离子扫描，液相色谱串联质谱仪上机测定。通过对比色谱图保留时间和光谱图的峰形以及质谱图，结果表明最终确证该批样品中非法添加物为甘草酸。UPLC-PDA方法中甘草酸检测限为20μg/mL,定量限为50μg/mL。本方法快速、灵敏、重现性好，适用于本批标称杨树花口服液中甘草酸的检测。  相似文献   

7.
结合简单快速的前处理方法和超高压液相色谱-三重四级杆/线性离子阱串联质谱(UPLC-Qtrap)技术,建立了猪肉中92种兽药残留同时检测的高通量筛查和定量方法。样品经简单快速的前处理后,经Kinetex Core-Shell色谱柱分离,分析时间仅13.5 分钟。质谱采用多反应监测－信息关联－增强子离子(MRM-IDA-EPI)采集方式及谱库检索技术,通过化合物的保留时间、离子对丰度比以及EPI标准谱库检索对比,可完成对92种兽药的快速筛查和确证。采用基质匹配标准溶液外标法定量。结果表明：在1～50 ng/mL猪肉基质匹配标准溶液浓度范围内呈良好线性关系,相关系数R2均大于0.990;方法定量限均为1 ng/g;在1~10 ng/g的添加浓度范围内92种药物的回收率为50%～120%,批内批间相对标准偏差均小于20％。  相似文献   

8.
建立了超高效液相色谱-静电轨道阱质谱法检测猪肉中21种磺胺类药物残留的检测方法。猪肉样品经90%乙腈水溶液提取,Oasis PRiME HLB固相萃取小柱净化,采用ZORBAX SB-C18 (3.0×100 mm,1.8 μm)色谱柱,0.1%的甲酸水溶液和0.1%甲酸-乙腈溶液作为流动相进行梯度洗脱。质谱采用正离子扫描,利用含有保留时间、母离子和子离子精确分子量等信息的数据库进行定性,以一级质谱全扫描母离子的峰面积进行定量分析。21种磺胺类药物在最优化条件下分离良好,2~200 ng/mL质量浓度范围内线性回归关系良好(线性相关系数r≥0.99)。21种磺胺类药物的平均回收率为63.5%~94.2%,相对标准偏差为3.8%~10.8%。本方法具有简便、快速、灵敏、准确等特点,适用于猪肉中的21种磺胺类药物残留的筛查测定。  相似文献   

9.
对农业执法案件中缴获的未知粉末进行分析研究。应用超高效液相色谱-飞行时间高分辨质谱（UPLC-TOF-HRMS）获得未知物分子离子峰的精确质量数、天然同位素信息，二级特征碎片的精确质荷比，并应用SCIEX PeakView及MasterView软件进行分析。经过靶向及非靶向筛查，同时参考文献报道，推导出未知粉末中的疑似化合物。采用高效液相色谱-二极管阵列检测器（HPLC-PDA）法及UPLC-TOF-HRMS法进行了双重确证。结果显示该未知粉末中含克仑特罗（16 g?kg-1）及其合成前体克仑特罗杂质B（455 g?kg-1）。本文详述的分析技术可为未知添加物的筛查和确证提供思路和技术参考。  相似文献   

10.
农业部《饲料添加剂品种目录(2013)》收录了3种维生素K_3类饲料添加剂,即亚硫酸氢钠甲萘醌(MSB)、亚硫酸氢烟酰胺甲萘醌(MNB)和二甲基嘧啶醇亚硫酸甲萘醌(MPB),目前发布的标准中分别采用甲萘醌的沉淀反应、二氧化硫的气味鉴别及烟酰胺的薄层色谱法来鉴别,方法繁锁,专属性不强。文章建立了用高效液相色谱法鉴别3种维生素K_3类化合物,采用Waters Atlantis~?HILIC Sili-ca色谱柱(4.6 mm×250 mm,5μm);以乙腈/水(80.20)为流动相,230 nm为检测波长,流速1 ml/min,结果显示MSB为1个主峰、MNB和MPB均出现2个主峰,即亚硫酸氢甲萘醌、烟酰胺和二甲基嘧啶醇,3个色谱峰的分离度R≥1.9,MSB、MPB、MNB在该色谱条件下得到较好的分离。MPB中亚硫酸氢甲萘醌和二甲基嘧啶醇峰的相对保留时间均为0.19,MNB中亚硫酸氢甲萘醌和烟酰胺的相对保留时间为0.30~0.32。该色谱条件下,用保留时间或相对保留时间即能有效鉴别3种维生素K_3类化合物,方法简便、专属性强。  相似文献   

11.
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   

12.
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   

13.
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   

14.
Tropical Animal Health and Production -  相似文献   

15.
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   

16.
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   

17.
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   

18.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
  相似文献   

19.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

20.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

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