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本试验用外翻肠囊法研究高钙对肉仔鸡不同肠段(十二指肠、空肠和回肠)吸收不同形态锰的影响,以比较有机锰和无机锰在高钙条件下吸收特点的差异。采用单因子完全随机设计,培养液中添加的4种锰源分别为:硫酸锰、弱络合强度的蛋氨酸锰(Mn-MetE)、中等络合强度的氨基酸锰(Mn-AAA)和强络合强度的氨基酸锰(Mn-AAB)。为了扣除内源的影响,设置1个零添加锰水平处理。将40只31日龄AA肉公鸡随机分到以上5个组,每组8个重复,每个重复1只鸡,每只鸡的十二指肠、空肠和回肠分别作为相应肠段外翻肠囊的一个重复。结果表明:1)体外培养回肠肠囊对锰的吸收率显著高于十二指肠(P<0.01);2)回肠肠囊对强络合强度的Mn-AAB中锰的吸收率显著高于硫酸锰或中等络合强度的Mn-AAA(P<0.05)。本试验结果表明:在高钙条件下,络合形态的有机锰在体外培养的肉仔鸡肠囊中的吸收率显著高于无机形态的锰;强络合强度有机锰源中的锰能更强地抵抗小肠内的解离,比弱或中等络合强度的有机锰源更有利于锰的吸收。  相似文献   
3.
定性和定量分析一批兽药硫酸黏菌素可溶性粉中的未知添加物。照《中国兽药典》2010年版一部对该批检品用微生物检定法进行含量测定时,发现该样品的抑菌圈为虚圈,用薄层色谱鉴别该样品,未显示与标准品溶液一致的主斑点,怀疑该样品中有处方外非法添加物。采用超高效液相色谱-四级杆-飞行时间质谱(UHPLC-Q/TOF MS)对该样品进行筛查,发现疑似添加物,并使用液相色谱-二极管阵列检测(HPLC-DAD)法进行了双重确证和含量测定。该样品中非法添加物确证为磺胺氯达嗪和甲氧苄啶,添加量分别为58.5 mg/g和13.4 mg/g。本研究通过建立筛查方法为监管部门提供技术支撑,通过分析非法添加物的可能原因为打击兽药处方外非法添加提供了思路。  相似文献   
4.
Two kinds of corn were used as materials,changes of SOD,CAT,POD and MDA Contents after Germination of maize seeds in five different concentrations of manganese sulphate were studied.The results show that the content of MDA was significantly different among different varieties,difference was very significant compared with control.The activities of antioxidant enzymes of HuangJinNuo 1 first increased then decreased after treated with manganese sulfate,while that of YinLong BaiYuNou continuous elevation,the resistance of Maize after manganese sulphate increased during germination.  相似文献   
5.
Increasing pressures from agriculture and urbanization have resulted in drainage of many floodplains along the eastern Australian coastline, which are underlain by sulphidic sediments, to lower water tables and reduce soil salinity. This leads to oxidation of the sediments with a rapid decline in pH and an increase in salinity. Accurately mapping soil salinity and pH in coastal acid sulphate soil (CASS) landscapes is therefore important. One required map is the extent of highly acidic (i.e. pH < 4.5) areas, so that the application of alkaline amendments (e.g. lime) to neutralize the acid produced can be specifically targeted to the variation in pH. One approach is to use digital soil mapping (DSM) using ancillary information, such as an EM38, digital elevation models (DEM – elevation) and trend surface parameters (east and north). We used an EM38 in the horizontal (EM38h) and vertical (EM38v) modes together with elevation data to develop multiple linear regressions (MLR) for predicting EC1:5 and pH. For pH, best results were achieved when the EM38 ECa data were log‐transformed. By comparing MLR models using REML analysis, we found that using all ancillary data was optimal for mapping EC1:5, whereas the best predictors for pH were north, log‐EM38v and elevation. Using residual maximum likelihood (REML), the final EC1:5 and pH maps produced were consistent with previously defined soil landscape units, particularly CASS. The DSM approach used is amenable for mapping saline soils and identifying areas requiring the application of lime to manage acidic soil conditions in CASS landscape.  相似文献   
6.
Abstract

The present study was undertaken to identify the effects of manganese (Mn) on the activity of peroxidase (PO) and the amount of ascorbic acid (AsA) and lignin, as well as the cell viability of suspension-cultured tea cells (Camellia sinensis L. cv. Yabukita). Cells were grown in B5 medium (containing 0.06 mmol L?1 Mn) and cultured for 24 h in medium with a Mn concentration of 0.9 mmol L?1 as an excess treatment. No significant difference was observed between cellular growth and the viability of the cultured tea cells after treatment with excess Mn compared with cells grown under control conditions, although the content of Mn in cells in the excess Mn treatment was 12-fold higher than that of the control cells. The amount of total AsA was also not affected by the Mn treatment. The activity of ionically wall-bound peroxidase (IPO) increased in the presence of excess Mn, unlike the content of lignin. Conversely, the activities of soluble PO and covalently wall-bound PO decreased with excess Mn. These findings suggested that IPO might contribute to Mn tolerance in tea cells. However, its role in the mechanism(s) of Mn tolerance has not been elucidated.  相似文献   
7.
任军  石遥  刘方  田蓉  刘兴 《草业学报》2021,30(8):86-97
为明确锰矿废渣堆场重金属污染及优势草本植物重金属吸收特征,对贵州省典型锰矿废渣堆场的重金属污染风险进行了评价,并调查研究了锰矿废渣堆场草本植物的类群及重金属吸收特征。共采集优势草本植物18种,隶属11科18属,菊科和禾本科为优势科。对18种草本植物体地上部、地下部及其生长基质中Cr、Ni、Cu、Zn、Cd、Pb和Mn 7种重金属元素进行了测定,结果显示,锰矿废渣堆场重金属污染空间变异较大,Mn污染最严重,其次是Cd,属于Mn、Cd复合型污染。计算了草本植物对7种重金属元素的富集系数、转运系数,并对18种草本植物进行了聚类分析,综合分析了草本植物重金属吸收特征,结果显示,看麦娘对Cd富集系数达22.49,对Cd有较强的富集能力;五节芒、商陆对Cr、Ni具有较强的富集能力和转运能力;风毛菊和夏枯草对锰矿废渣区多种重金属均表现出较强的富集能力和转运能力。研究结果表明,锰矿废渣堆场主要为Mn和Cd污染,矿区本土自然生长的优势草本植物可作为生态修复的首选植物。  相似文献   
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9.
应用鲎试剂动态浊度法,将硫酸链霉素制备成4、2、1、0.5mg/mL溶液,定量添加标准内毒素进行干扰预试验,计算回收率,确定不干扰浓度为0.5—2mg/mL。从中选出1mg/mL为最佳浓度,然后进行3个批次硫酸链霉素正式干扰试验。在供试品中定量添加标准内毒素,其回收率分别为125.8%、126.1%、127.3%,均在50%-200%之间,说明此浓度的供试品对鲎试剂反应无干扰作用。因此,内毒素含量在0.015—1EU/mL范围内,将硫酸链霉素制备成浓度为1.0mg/mL的溶液,可用于细菌内毒素的定量检测。  相似文献   
10.
Elemental sulphur levels, sulphur localization in stems, and levels of sulphate, glutathione and cysteine were studied in pepper ( Capsicum annuum ) cvs Yolo Wonder (higher resistance) and Luesia (lower resistance) after inoculation with Verticillium dahliae , the cause of vascular wilt. Accumulation of elemental sulphur (S0) was first detected 10 days after inoculation in Yolo Wonder (mean S0 level 7·3  µ g g−1 DW), and 15 days after inoculation in Luesia (mean S0 level 3·3  µ g g−1 DW). The maximum level was reached 21 days after inoculation in Yolo Wonder (14·1  µ g g−1 DW). In control plants, elemental sulphur was not detected. SEM-EDX (scanning electron microscopy-energy dispersive X-ray microanalysis) indicated that the sulphur was not restricted to a specific location, but was dispersed throughout the vascular tissue. Sulphate levels showed a decline at the end of the experiment in inoculated plants, possibly related to the increase in sulphur levels seen in the two cultivars. The differences in sulphate levels between the two cultivars may be due to faster sulphate breakdown in cv. Yolo Wonder.  相似文献   
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