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《畜牧兽医科技信息》2015,(9)
本文试验以不同种类的动物饲料为原料,采用微波消解法处理样品,用火焰原子吸收法测Cu、Zn的含量,石墨炉法测Pb、Cd的含量。通过对比国标GB/T13080-2004《饲料中铅的测定原子吸收光谱法》、GB/T13082-1991《饲料中镉的测定》、GB/T13885-2003《饲料中钙、铜、铁、镁、锰、钾、钠和锌的测定原子吸收光谱法》的检测方法,得出结论:微波消解法在饲料重金属检测中具有快速、简单、安全、准确等特点。 相似文献
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为研究微波消解-火焰原子吸收法测定饲料中钾、钠、钙、镁、铁、锰、铜和锌8种元素含量的可行性分析,本实验采取微波消解法代替传统的干灰化法,加入氯化铯、硝酸镧作为消电离剂及掩蔽剂,各元素的质量浓度在一定范围内与吸光度值呈线性关系,而且线性相关系数(R2)均达到0.995以上,满足仪器的要求;曲线最低点可以做到0.10mg/L,最高点可以做到7.00mg/L;方法检出限为0.68~207mg/kg,方法重现性(RSD)均小于3%,质控样在质控范围内,通过对实际多种类样品的测定,结果的准确度和精密度均符合饲料国标要求。综上,微波消解-火焰原子吸收法是一种速度快、成本低的联合检测方式,可以用于不同类型的饲料中钾、钠、钙、镁、铁、锰、铜和锌8种元素含量的测定。 相似文献
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通过观察钙离子拮抗剂对秋粘夜蛾蛹的卵细胞(sf-9)吸收Ca2+、Mg2+浓度的影响,旨在探讨不同钙通道阻滞剂对细胞Ca2+的定性、定量研究以及对昆虫细胞生理生化的影响。采用细胞培养、离心、原子吸收光谱测定等方法,研究不同的钙离子拮抗剂:Nife、Nimo、Nitren作用于SF-9细胞,分别测定纯培养液与钙离子拮抗剂处理并滤掉细胞后的培养液中的钙镁离子浓度,通过计算两者的浓度差值,得出SF-9细胞在一定时间内吸收的钙镁离子量,并进行比较。原子吸收光谱法测定的结果显示:经钙离子拮抗剂处理后的样品,测得Ca2+、Mg2+浓度有所增加,也就是说细胞吸收的Ca2+、Mg2+的量比对照组纯细胞培养液要少。研究表明:由于钙离子拮抗剂使得钙离子通道的通透性发生改变,使得细胞对Ca2+的吸收量大大减少;而Ca2+又具有维持和调节细胞膜的通透性作用,Ca2+的吸收量不足使得细胞膜的通透性降低,进而影响了细胞对Mg2+的吸收。但钙离子拮抗剂主要还是先影响细胞对于Ca2+的吸收的,从而使细胞的生理和生化反应发生改变,实现对细胞内环境的精细调节。 相似文献
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[目的]依据GB 5009.92—2016《食品安全国家标准食品中钙的测定》标准中第一法,用火焰原子吸收光谱法测定牛乳中钙含量,评定其不确定度。[方法]建立数学模型,分析该测定过程的不确定度来源,并量化评定,计算合成相对标准不确定度和扩展不确定度。[结果]取置信概率P为95%时,钙含量的扩展不确定度为3.22 mg/100 g,即该乳中钙含量测定结果为X=(123.80±3.22)mg/100g。[结论]不确定度的主要来源是标准工作曲线溶液的配制和标准工作曲线的拟合、测定重复性两个方面,评定不确定度的结果可以为火焰原子吸收光谱法测定牛乳中钙含量的准确性提供参考。 相似文献
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本文介绍了一种微波消解-火焰原子吸收法测定饲料中钙的方法,对样品处理、测定方法和最佳条件的选择进行了研究。在测定饲料样品时,由于基体引起的背景吸收比较严重,为此利用自吸进行背景校正,效果比较理想。同时进行高低浓度加标回收测定,低浓度加标回收率为96.7%,高浓度加标回收率为101%。证明该方法完全能满足检测工作需要。 相似文献
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用火焰原子吸收光谱法间接测定饲料添加剂维生素B12粉中维生素B12的含量。该方法通过测定样品中的钴离子浓度计算维生素B12的含量。经试验,该方法在0.20～2.00μg/mL线性关系良好,r=0.9992;有机载体和无机载体中的维生素B12平均回收率分别为99.21%和98.98%,方法的检出限为0.061μg/mL。本法操作简便易行,适用于饲料添加剂维生素B12粉中维生素B12含量测定。 相似文献
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为评估微生物法测定婴幼儿配方乳粉中叶酸含量的不确定度,结合《GB 5009.211—2014 食品安全国家标准 食品中叶酸的测定》及不确定度相关评估标准以及统计学方法,对婴幼儿配方乳粉中叶酸含量测定过程中的不确定度进行分析和评估。结果显示,婴幼儿配方乳粉中叶酸含量为（148.49±7.37） μg/100 g,k=2。其中,标准溶液和样液的配制过程是影响检测结果的主要因素,仪器测量偏差、重复性和检测方法是次要因素。表明微生物法测定婴幼儿配方乳粉中叶酸含量时不确定度较小,可用于婴幼儿配方乳粉中叶酸含量的测定。 相似文献
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1. The effect of dietary palmitic acid on body weight and bone-ash of chicks fed three concentrations of calcium was studied in a 2 X 3 factorial design (0 and 10% palmitic acid, 0.4, 0.7 and 1.0% calcium). 2. Body weight of chick not influenced by the calcium concentration when palmitic acid was not included in the diet. 3. When 10% palmitic acid was included the body weight of chicks fed 0.4 and 0.7% calcium was lower (P less than 0.01) than for the other groups. 4. Bone-ash was lower (P less than 0.01) for chicks fed 0.4% calcium than for the other two calcium concentrations when palmitic acid was not added and palmitic acid at 10% of the diet reduced bone-ash of the chicks fed 0.4 and 0.7% calcium (P less than 0.01). 相似文献
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本试验采用终点法检测血浆中Ca2+浓度变化,分别采用免疫组织化学SP法及荧光定量PCR法检测奶牛胎儿胎盘eNOS蛋白及其mRNA的表达。通过对血浆中Ca2+浓度的检测及胎儿胎盘内皮型一氧化氮合酶(eNOS)表达量的研究,探讨奶牛胎衣不下的发生与这些物质变化的关系。结果表明,胎衣不下组奶牛血浆中Ca2+浓度在分娩前后均低于正常组;两组eNOS蛋白均在胎盘绒毛滋养层细胞和内皮细胞胞浆内表达,蛋白的表达量差异显著(P0.05);两组胎儿胎盘eNOS mRNA表达量差异显著(P0.05)。本研究证明分娩前后血浆中Ca2+水平对奶牛胎衣不下的发生有重要的调节作用,低浓度的Ca2+容易导致子宫收缩无力,同时影响eNOS在胎儿胎盘绒毛中的表达。 相似文献
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本试验建立了微波消解-石墨炉原子吸收法测定兔皮中痕量镉的方法。采用微波消解技术,在阶梯升高温度和加热功率条件下,用硝酸和过氧化氢彻底消解兔皮样品,消解后的样品用石墨炉原子吸收分光光度法测定微量的镉。结果:镉浓度在0～60.0μg/L范围内呈良好的线性关系,相关系数镉r=0.999 8;最低检出限镉为0.036 5mg/kg;对样品进行8次重复性实验,其相对标准偏差为3.147%;镉回收率在97.0%～105.8%之间。该方法具有操作简便、测定快速、准确度高的优点,适合于兔皮中痕量镉的日常批量检测。 相似文献
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1. An experiment was conducted to test the hypothesis that severe food restriction throughout the onset of lay or delaying photostimulation by 5 weeks would decrease the number of ovarian hierarchical follicles in male-line turkeys. It was proposed that a decrease in the number of hierarchical follicles would lower plasma oestradiol concentration and be associated with higher vaginal collagen content and a lower propensity to prolapse of the oviduct. 2. Five weeks after photostimulation, neither restriction to 63% of ad libitum body weight nor delayed onset of photostimulation had any significant effect on follicle number, plasma oestradiol concentration or vaginal collagen content. 3. It was concluded that neither food restriction nor delayed photostimulation can be used to control the over-development of the ovarian hierarchy in male-line turkeys. 相似文献
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M Baran 《Veterinární medicína》1985,30(12):733-738
In a trial with rams, application of polyethylene powder (PE) as a marker for determination of feed passage rate through the digestive tract and three methods of its determination in feed and feces were tested. PE with particle size 0.4 mm and specific weight 0.924 was administered to animals in feed and its excretion was studied during the period of 10 days in two experimental diets based on secondary sources of wood, and in one control diet. PE formed 3.9% (D-2), 3.5% (D-1) and 4% (control) of the diet dry matter and was determined by gravimetric method; for mineralizing organic matter in the sample, nitric acid (Chandler et al., 1964), mixture of sulphuric and nitric acid (Kemmink and Dijkstra, 1968) and sodium hydroxide (Boling et al., 1967) were used. The most suitable was the method using sodium hydroxide, by which 81.23% (D-2), 84.78% (D-1) and 86.6% (control) of PE recovery was determined in feces samples. 相似文献
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为快速有效地检测动物源性食品中氯苯胍及其代谢物残留,研究建立一种在鸡蛋、鸡肉、牛肉、鱼肉和猪肉5种动物源性食品中,同时检测氯苯胍及其代谢物（对氯苯甲酸、对氯苯甲酰氨基乙酸）残留的超高效液相色谱-串联质谱（UPLC-MS/MS）法。样品经过2%（V/V）甲酸乙腈溶液提取,无水硫酸钠去除水分,氮吹浓缩后甲醇复溶,正己烷除脂,高速冷冻离心,得到净化后的样品进行上机测定。选用Waters ACQUITY UPLC BEH C18色谱柱（2.1 mm×100 mm,1.7 μm）,将甲醇-0.1%甲酸水溶液作为流动相进行梯度洗脱。通过多反应检测（MRM）,在正/负离子模式下,采用基质匹配外标法,同时对3种化合物进行定性和定量分析。结果显示,氯苯胍、对氯苯甲酸和对氯苯甲酰氨基乙酸在各自浓度范围内线性关系良好,相关系数R2>0.999。氯苯胍的检出限（LOD）和定量限（LOQ）分别为0.5和1.0 μg/kg,对氯苯甲酸的LOD和LOQ分别为2.5和5.0 μg/kg,对氯苯甲酰氨基乙酸的LOD和LOQ分别为1.0和2.5 μg/kg。不同基质中,3种化合物在4个添加水平（氯苯胍：1.0、25、50、100 μg/kg;对氯苯甲酸：5.0、25、50、100 μg/kg;对氯苯甲酰氨基乙酸：2.5、25、50、100 μg/kg）的平均回收率为76.0%~95.9%,相对标准偏差（RSDs,n=6）为2.6%~10.6%。基质效应|ME|为0.2%~26.2%,其中氯苯胍在鸡蛋中,对氯苯甲酰氨基乙酸在鸡肉、牛肉和鱼肉中存在较强的基质效应（|ME|>20%）,空白猪肉可作为代表基质用于3种化合物的定量分析。本方法前处理简单,灵敏度较高,重现性好,可用于动物源食品中氯苯胍及其代谢物残留的测定。 相似文献
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The goal of this study was to determine the effect of intravenous (IV) administration of phosphite on the serum concentration of inorganic phosphorus in cows. Twelve clinically healthy cows were divided into four groups of three. All cows received 600 mL of a 40% calcium borogluconate solution; three cows each received this as a rapid (20 min) IV infusion with and without 6% magnesium hypophosphite, and three other cows each received this as a slow IV infusion (8 h) with and without 6% magnesium hypophosphite. Samples of blood were collected for the determination of serum concentrations of calcium, inorganic phosphorus and magnesium before and 10, 20, 40, 60 and 90 min and 2, 3, 4, 5, 6, 7, 8, 24, 48 and 72 h after the start of treatment. The concentration of calcium increased after treatment in all cows but the increase was most rapid in cows that received the rapid infusion. In cows that received the rapid IV infusion containing magnesium hypophosphite, the mean concentration of inorganic phosphorus decreased significantly 3-4 h after treatment compared with initial serum levels. The serum concentration of inorganic phosphorus did not change significantly in cows that received the rapid IV solution without magnesium hypophosphite or the slow IV infusion with or without magnesium hypophosphite. The serum concentration of magnesium increased after treatment in all cows receiving magnesium hypophosphite but remained unchanged in the others. The rapid infusion of calcium borogluconate without magnesium hypophosphite made all three cows anorexic and hypercalcaemic and the slow infusion made 1/3 anorexic. It is concluded that the IV administration of a calcium solution containing magnesium hypophosphite does not increase the serum concentration of inorganic phosphorus. 相似文献
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高钙饲粮对青年蛋鸡血清一氧化氮浓度和抗氧化功能的影响 总被引：1，自引：0，他引：1
本试验旨在研究高钙饲粮对青年蛋鸡血清一氧化氮（ＮＯ）浓度和抗氧化功能的影响。将 ３５日龄 １００羽伊沙蛋鸡随机均分为对照组（含钙 １．００％）和高钙组（含钙 ３．７８％），每组 ５个重复，每个重复 １０羽。每天观察鸡的精神状态、食欲和粪便情况。在饲喂高钙饲粮第 ０、８、１６、２４和 ３２天时，分别测定 ２组鸡的血清中 ＮＯ浓度和丙二醛含量及抗氧化酶系统的变化。结果表明：１）高钙饲粮能引起青年蛋鸡长期腹泻，在饲喂高钙饲粮的第 ８天就发生高血钙症。２）与对照组相比，高钙组在饲喂高钙饲粮第 ８天和第 １６天血清 ＮＯ浓度无显著变化（Ｐ＞０．０５），第２４天和第 ３２天显著升高（Ｐ＜０．０５）；第 ８天和第 ２４天血清超氧化物歧化酶活性、总抗氧化能力无显著变化（Ｐ＞０．０５），第 １６天显著升高（Ｐ＜０．０５），第 ３２天显著降低（Ｐ＜０．０５）；第 ８、１６、２４天血清丙二醛含量无显著变化（Ｐ＞０．０５），第 ３２天显著升高（Ｐ＜０．０５）；第 ２４天和第 ３２天黄嘌呤氧化酶活性有升高趋势（Ｐ＞０．０５）。结果提示，饲喂高钙饲粮可导致青年蛋鸡发生长期腹泻，引起高血钙症，导致其机体内自由基的产生与清除的动态平衡遭到破坏，使自由基的产生远远超出清除能力。 相似文献
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Toribio RE Kohn CW Chew DJ Sams RA Rosol TJ 《American journal of veterinary research》2001,62(6):938-947
OBJECTIVE: To evaluate calcium balance and parathyroid gland function in healthy horses and horses with enterocolitis and compare results of an immunochemiluminometric assay (ICMA) with those of an immunoradiometric assay (IRMA) for determination of serum intact parathyroid hormone (PTH) concentrations in horses. ANIMALS: 64 horses with enterocolitis and 62 healthy horses. PROCEDURES: Blood and urine samples were collected for determination of serum total calcium, ionized calcium (Ca2+) and magnesium (Mg2+), phosphorus, BUN, total protein, creatinine, albumin, and PTH concentrations, venous blood gases, and fractional urinary clearance of calcium (FCa) and phosphorus (FP). Serum concentrations of PTH were measured in 40 horses by use of both the IRMA and ICMA. RESULTS: Most (48/64; 75%) horses with enterocolitis had decreased serum total calcium, Ca2+, and Mg2+ concentrations and increased phosphorus concentrations, compared with healthy horses. Serum PTH concentration was increased in most (36/51; 70.6%) horses with hypocalcemia. In addition, FCa was significantly decreased and FP significantly increased in horses with enterocolitis, compared with healthy horses. Results of ICMA were in agreement with results of IRMA. CONCLUSIONS AND CLINICAL RELEVANCE: Enterocolitis in horses is often associated with hypocalcemia; 79.7% of affected horses had ionized hypocalcemia. Because FCa was low, it is unlikely that renal calcium loss was the cause of hypocalcemia. Serum PTH concentrations varied in horses with enterocolitis and concomitant hypocalcemia. However, we believe low PTH concentration in some hypocalcemic horses may be the result of impaired parathyroid gland function. 相似文献