Resorbable bioceramics are attractive for medical applications such as bone substitution. Biochemical analysis on cells cultured on these biomaterials is vital to predict the impact of the materials in vivo and RNA ex...Resorbable bioceramics are attractive for medical applications such as bone substitution. Biochemical analysis on cells cultured on these biomaterials is vital to predict the impact of the materials in vivo and RNA extraction is an essential step in gene expression study using RT-qPCR. In this study, we describe simple modifications to the TRIzol? RNA extraction protocol widely used in biology and these allow high-yield extraction of RNA from cells on resorbable calcium phosphates. Without the modifications, RNA is trapped in the co-precipitated calcium compounds, rendering TRIzol? extraction method infeasible. Among the modifications, the use of extra TRIzol? to dilute the lysate before the RNA precipitation step is critical for extraction of RNA from porous ?-tricalcium phosphate (?-TCP) discs. We also investigate the rationale behind the undesirable precipitation so as to provide clues about the modifications required for other resorbable materials with high application potential in bone tissue engineering.展开更多
氨氮是评价水体受人为影响程度的重要参数,也因此被我国纳入主要污染物排放总量控制指标,正确有效地检测水体氨氮适时浓度,为评估水体水质变化趋势提供了基础数据保障。本文采取研究区实际水样,讨论氨氮测定的最大干扰以及如何有效避免...氨氮是评价水体受人为影响程度的重要参数,也因此被我国纳入主要污染物排放总量控制指标,正确有效地检测水体氨氮适时浓度,为评估水体水质变化趋势提供了基础数据保障。本文采取研究区实际水样,讨论氨氮测定的最大干扰以及如何有效避免干扰的问题。结果表明:当水中钙镁离子总量大于1 mmol/L时,比色管中溶液显色反应会受到浑浊干扰而影响测定;在加入纳氏试剂显色前,向比色管中加入1 m L酒石酸钾钠和1 m L氢氧化钠做掩蔽剂,能有效避免浑浊问题。展开更多
目的探讨血清钙试剂引起血清磷测定结果升高的原因及处理方法。方法随机选取20例健康体检者新鲜血清标本,先单独测定血清磷(P0组),再做钙、磷同测(P1组),接着分别做试剂针<from Ca to P>的加水清洗200μL(P2组)、加wash1 200μL/...目的探讨血清钙试剂引起血清磷测定结果升高的原因及处理方法。方法随机选取20例健康体检者新鲜血清标本,先单独测定血清磷(P0组),再做钙、磷同测(P1组),接着分别做试剂针<from Ca to P>的加水清洗200μL(P2组)、加wash1 200μL/加水清洗200μL(P3组)、加wash2 200μL/加水清洗200μL(P4组),在以上3种情况下钙、磷同测,共得到5组血清磷的测定数据。将后4组数据分别与P0组用配对t检验的方法进行统计学分析;调整项目测试顺序并加清洗(Probe<R1>,From Test<All>,To Test P<water 200μL>)后,随机选择当天含钙、磷两个检测项目的病人标本20份记录血清磷测定结果,然后对这20份标本做血清磷的单独测定,再将两组数据用配对t检验的方法进行统计学分析。结果 P0组与P1组,P0组与P2组,P0组与P3组,P0组与P4组进行比较差异均存在显著性意义(P<0.01);调整项目测试顺序后差异无显著性意义,P>0.05。结论残留的血清钙试剂可对磷的测定造成非常严重的正干扰,通过加设特殊清洗的方法只能降低干扰程度,只有调整项目测试顺序才能彻底消除钙试剂可对磷的测定干扰。展开更多
The mechanisms of aid-leaching reagent calcium fluoride in the extracting vanadium processes were researched by comparing the blank extraction with the extraction with calcium fluoride as aid-leaching reagent. The lea...The mechanisms of aid-leaching reagent calcium fluoride in the extracting vanadium processes were researched by comparing the blank extraction with the extraction with calcium fluoride as aid-leaching reagent. The leaching experiments were carried out under the conditions of 95 ~C, 6 h, 1.5 ml.g-1, 15 vol % H2SO4, and 5 % calcium fluoride （mass ratio of CaF2 to stone coal）. The concentrations of hydrogen ion were adjusted from initial 1.82 and 4.79 mol.L-1 to the pH of 1.80 4- 0.05 by 200 g.L-1 lime milk, respectively. The solvent extraction experiments were carded out under the organic phase using 15 vol% D2EHPA, 5 vol% TBP, and 80 vol% sulfonated kerosene and O/A phase ratio of 1/4. The leaching rate of vanadium and six-stage countercurrent solvent extraction rate of vanadium can be remarkably improved from 66.71 to 92.97 % and 81.15 to 98.81%, respectively, when calcium fluoride was added as aid-leaching reagent. In the leaching process, fluorine can enhance the breakage of the structure of vanadium-bearing minerals. Meanwhile, fluoride ion can combine with iron ion to generate acid-insoluble iron fluoride hydrate （Fe2Fs.7H20） and consume all ferric ions and a portion of ferrous ions. In adjusting pH value process, the massive impurities are decreased to form KA1SO4 and FeA1Fs. In solvent extraction process, fluorine can prevent the formation of ferric hydroxide colloids and eliminate the formed unstable ferric hydroxide colloids and the silicon-containing colloids to promote the sufficient contact between the aqueous phase and the organic phase and the sufficient reaction.展开更多
文摘Resorbable bioceramics are attractive for medical applications such as bone substitution. Biochemical analysis on cells cultured on these biomaterials is vital to predict the impact of the materials in vivo and RNA extraction is an essential step in gene expression study using RT-qPCR. In this study, we describe simple modifications to the TRIzol? RNA extraction protocol widely used in biology and these allow high-yield extraction of RNA from cells on resorbable calcium phosphates. Without the modifications, RNA is trapped in the co-precipitated calcium compounds, rendering TRIzol? extraction method infeasible. Among the modifications, the use of extra TRIzol? to dilute the lysate before the RNA precipitation step is critical for extraction of RNA from porous ?-tricalcium phosphate (?-TCP) discs. We also investigate the rationale behind the undesirable precipitation so as to provide clues about the modifications required for other resorbable materials with high application potential in bone tissue engineering.
文摘氨氮是评价水体受人为影响程度的重要参数,也因此被我国纳入主要污染物排放总量控制指标,正确有效地检测水体氨氮适时浓度,为评估水体水质变化趋势提供了基础数据保障。本文采取研究区实际水样,讨论氨氮测定的最大干扰以及如何有效避免干扰的问题。结果表明:当水中钙镁离子总量大于1 mmol/L时,比色管中溶液显色反应会受到浑浊干扰而影响测定;在加入纳氏试剂显色前,向比色管中加入1 m L酒石酸钾钠和1 m L氢氧化钠做掩蔽剂,能有效避免浑浊问题。
文摘目的探讨血清钙试剂引起血清磷测定结果升高的原因及处理方法。方法随机选取20例健康体检者新鲜血清标本,先单独测定血清磷(P0组),再做钙、磷同测(P1组),接着分别做试剂针<from Ca to P>的加水清洗200μL(P2组)、加wash1 200μL/加水清洗200μL(P3组)、加wash2 200μL/加水清洗200μL(P4组),在以上3种情况下钙、磷同测,共得到5组血清磷的测定数据。将后4组数据分别与P0组用配对t检验的方法进行统计学分析;调整项目测试顺序并加清洗(Probe<R1>,From Test<All>,To Test P<water 200μL>)后,随机选择当天含钙、磷两个检测项目的病人标本20份记录血清磷测定结果,然后对这20份标本做血清磷的单独测定,再将两组数据用配对t检验的方法进行统计学分析。结果 P0组与P1组,P0组与P2组,P0组与P3组,P0组与P4组进行比较差异均存在显著性意义(P<0.01);调整项目测试顺序后差异无显著性意义,P>0.05。结论残留的血清钙试剂可对磷的测定造成非常严重的正干扰,通过加设特殊清洗的方法只能降低干扰程度,只有调整项目测试顺序才能彻底消除钙试剂可对磷的测定干扰。
基金financially supported by the Key Science and Technology Support Program (No. 2011BAB05B01) from the Ministry of ScienceTechnology of China and the Special Science and Technology Program (No. 201009013) from the Ministry of Environmental Protection of China
文摘The mechanisms of aid-leaching reagent calcium fluoride in the extracting vanadium processes were researched by comparing the blank extraction with the extraction with calcium fluoride as aid-leaching reagent. The leaching experiments were carried out under the conditions of 95 ~C, 6 h, 1.5 ml.g-1, 15 vol % H2SO4, and 5 % calcium fluoride （mass ratio of CaF2 to stone coal）. The concentrations of hydrogen ion were adjusted from initial 1.82 and 4.79 mol.L-1 to the pH of 1.80 4- 0.05 by 200 g.L-1 lime milk, respectively. The solvent extraction experiments were carded out under the organic phase using 15 vol% D2EHPA, 5 vol% TBP, and 80 vol% sulfonated kerosene and O/A phase ratio of 1/4. The leaching rate of vanadium and six-stage countercurrent solvent extraction rate of vanadium can be remarkably improved from 66.71 to 92.97 % and 81.15 to 98.81%, respectively, when calcium fluoride was added as aid-leaching reagent. In the leaching process, fluorine can enhance the breakage of the structure of vanadium-bearing minerals. Meanwhile, fluoride ion can combine with iron ion to generate acid-insoluble iron fluoride hydrate （Fe2Fs.7H20） and consume all ferric ions and a portion of ferrous ions. In adjusting pH value process, the massive impurities are decreased to form KA1SO4 and FeA1Fs. In solvent extraction process, fluorine can prevent the formation of ferric hydroxide colloids and eliminate the formed unstable ferric hydroxide colloids and the silicon-containing colloids to promote the sufficient contact between the aqueous phase and the organic phase and the sufficient reaction.
