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1.
建立了微波消解-石墨炉原子吸收光谱法(GFAAS)测定9种中兽药散剂中铅含量的方法。采用微波消解技术处理样品,对消解溶剂、微波条件以及石墨炉原子吸收法的测定条件进行了优化。结果表明,以HNO3+HClO4+H2O2(4+0.5+1,V+V+V)作为微波消解溶剂最佳,基体改进剂Pd(NO3)2可有效地消除基体的影响。此方法的线性范围为5.00~80.00 ng/mL(r=0.9978),检出限为0.39 ng/mL,添加回收率为87.1%~96.3%,相对标准偏差(RSD)为1.9%~6.9%(n=9),将该方法应用于9种中兽药散剂中铅含量的测定,结果令人满意。  相似文献   

2.
作者研究了用微波消解法对牛奶样品进行前处理,操作简便,减少了操作带来的误差,再用石墨炉原子吸收光谱法测定其中铅的含量。该方法测定的线性范围在0~40 ng/mL,相关系数r=0.9998。牛奶样品添加回收率为90%~95%。该方法准确、可靠,而且大大提高了检测效率。  相似文献   

3.
采用微波制样技术对样品进行消解,减少了消化过程中硒的损失,利用石墨炉原子吸收光谱法对醋酸地塞米松中微量硒进行测定.以4 mg/mL Pd(NO3)2作为基体改进剂,灰化温度为950 ℃,原子化温度为2 100 ℃时,经氘灯校正背景,测定硒含量,回收率在89.24%~112.37% 之间,方法的相对标准偏差为7.42%,检出限为0.53 ng/mL.该法具有简便、快速、灵敏、稳定、准确等优点,适用于醋酸地塞米松中微量硒的分析测定.  相似文献   

4.
首次对比研究了塞曼效应石墨炉原子吸收法测定生物样品中钼含量。以硝酸钯 (Pd(NO3 ) 2 )、三氯醋酸 (TCA)、及Pd(NO3 ) 2 TCA作为基体改进剂可使吸光度分别增加 5倍、12 .4倍及 19倍 ,检出下限分别为 2 5ng/mL、12ng/mL、10ng/mL。以塞曼效应扣除背景吸收 ,能有效地克服Fe、Cu、Mn等共存离子的干扰。通过对奶牛、雏鸡血清及组织中钼含量的测定可知 ,混合型的基体改进剂能够提高钼含量测定的灵敏度及回收率  相似文献   

5.
建立石墨炉原子吸收分光光度法(AA400)测定生猪肉中镉、铅.方法:采用高压消解处理生猪肉样品,以磷酸二氢铵和硝酸镁溶液作为基体改进剂进,石墨炉原子吸收分光光度计测定生猪肉中镉、铅.结果在优化实验条件下,本法镉的检出限为0.2376,相对标准偏差(RSD)为2.904% (n=11,c=5μg/L)、相关系数(r)为0.9994;本法铅的检出限为0.6439,相对标准偏差(RSD)为3.178% (n=11,c=50 μg/L)、相关系数(r)为0.9995;标准曲线线性关系良好.结论:该方法检出限低,灵敏度高,标准曲线线性好,适用于生猪肉中镉、铅的测定.  相似文献   

6.
本实验旨在建立检测饲料中镉含量的石墨炉原子吸收光谱法,并对测定条件进行优化选择,以实现快速、准确检测。采用干灰化法对饲料样品进行前处理,在228.8 nm共振线,采用塞曼校正,应用石墨炉原子吸收法测定饲料中镉含量。结果表明:镉浓度为0~2μg/L时,线性关系良好,相关系数为0.9986;方法检出限为0.0255μg/L;精密度(RSD)为0.603%(n=11);加标回收率为99.84%~102.0%。石墨炉原子吸收法具有操作简便、快速、灵敏度高等特点,并有较高的回收率,能适用于饲料中镉含量的测定。  相似文献   

7.
微波消解石墨炉原子吸收光谱法测定植物中的铅   总被引:2,自引:1,他引:1  
研究了微波消解石墨炉原子吸收分光光度法测定植物中铅的最佳实验条件、测定方法的准确度和精确度。结果表明,测定植物中铅的最佳酸体系为5 mL HNO3-3 mL H2O2-2 mL HF、最佳消解条件为微波炉功率600 W、温度180℃消解15 min,石墨炉的最佳工作条件为90℃干燥45 s、900℃灰化20 s、原子化温度1 400℃和洁净温度2 500℃。用该法样品加标回收率为95.81%~100.09%,检出限为0.068 4mg/kg,相对标准偏差为1.2%~5.6%。  相似文献   

8.
采用微波消解法对牛奶和羊肉样品进行前处理,再用石墨炉原子吸收分光光度法测定其中铅的含量。该法测定的线性范围在0~40ng/mL,相关系数r=0.9997。羊肉和牛奶样品添加回收率为91%~94%。该法不仅准确,可靠,减少了操作带来的误差,而且大大提高了检测效率。  相似文献   

9.
采用水浴湿法消化 ,以 Pd( NO3) 2 - Triton X- 10 0作为基体改进剂 ,应用 Zeem an石墨炉原子吸收法测定了肝组织硒含量。试验结果表明 ,肝组织经水浴湿法消化测得的硒含量与消化炉湿法消化测定结果基本一致 ( P >0 .0 5) ,相对标准偏差为 1.11%,回收率为 95.80 %~ 10 0 .4 0 %。石墨炉原子吸收法测定硒的检测限为 5.0 μg/ L  相似文献   

10.
吐鲁番葡萄干和张掖红提葡萄干在常压微沸(90℃~95℃)条件下采用V(硝酸):V(高氯酸)=4:1消解,应用火焰原子吸收法测定样品中的金属元素Na、K、Mg、Ca、Cu、Zn、Fe、Mn含量,运用石墨炉原子吸收光谱法检测样品中金属元素Pb和Cd的含量。通过仪器最佳工作条件和试验方法研究从而确定出不同元素的含量。结果表明:样品中K、Na、Mg、Ca含量较大,Mn、Zn、Fe、Cu、Pb含量较少,Cd未检出。方法的相对标准偏差为0.57%~2.12%。  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.
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   

13.
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   

14.
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   

15.
16.
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   

17.
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   

18.
A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered, coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the gland cisterns and teat cisterns. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

19.
Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L3) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L3 developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone.  相似文献   

20.
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