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 共查询到20条相似文献,搜索用时 203 毫秒
1.
朱岩  李刚 《科技通报》1994,10(5):297-300
采用梯度淋洗离子色谱法对碱金属、碱土金属及其铵类进行分析,该方法采用CG3分离柱,0.3mmol/LHCl为淋洗剂,4min后改用3.0mmol/L盐酸间苯二胺和5.0mmo1/LHCl作淋洗剂(流速2.0ml/min)采用微膜抑制柱,再生液为50mmol/LKOH(流速2.0ml/min),用电导检测法分别检测Li ̄+、Na ̄+、NH、K ̄+和Mg ̄(2+)、Ca ̄(2+)、Sr ̄(2+)、Ba ̄(2+).对分析条件进行了探讨.  相似文献   

2.
沈虹虹  洪瑛 《科技通报》1997,13(6):427-429
本实验中采用了新药物研究中认可的CCL4诱导大白鼠慢性肝损害的模型作为研究对象.病理结果说明使用软肝丸有良好的抗细胞坏死,能明显抑制肝纤维化过程,促进肝细胞再生作用.药效学的研究,也提示软肝丸可以降低血清ALT及肝组织中的羟脯氨酸的含量.  相似文献   

3.
邱启任  潘均 《科技通报》1997,13(3):167-169
采用甲基磺酸乙酯(EMS)诱变草鱼吻端组织细胞(ZC-7901).用乌苯苷(Ouabain)筛选抗药性突变体.结果表明,EMS对草鱼细胞的诱变效果与该药物对哺乳类细胞的诱变效果有明显差异.草鱼细胞对乌苯苷的敏感性也大大低于哺乳类细胞.ZC-7901细胞在传代后24h,用浓度为2.8mg/ml的EMS处理24h,诱变效果较理想,细胞杀伤率约30%,这比通常用EMS诱变哺乳类细胞所使用的浓度(0.4mg/ml)增大了7倍,存留下来的细胞用浓度为25mmol/L乌苯苷筛选抗性突变体,有少数细胞存活,并具有分裂增殖能力.但在细胞瓶内不易形成单层  相似文献   

4.
郜洪文 《科技通报》1995,11(4):221-224
本文研究β修正光度法测定工业废水中痕量砷,它能消除过量BRB的干扰提高分析敏度、精密度和准确度。结果表明砷浓度0-0.40mg/L时,修正吸光度有良好线性关系,检出限0.004mg/L,加标回收率93.0%-111%,相对标准偏差RSD≤6.5%,该方法适合于化工废水、城市污水及各种环境水质分析。  相似文献   

5.
本文系统地研究了甲硝唑在汞电极上的电极过程,证明了该电极过程为一含有吸附作用的不可逆的扩散控制过程,电子转移数为4,不可逆系数a=0.714.建立了甲硝唑的单扫示波极谱测定法,在0.20mol/L的NaCl溶液中,于-0.71V(vsSCE)处的峰高与浓度[(0.02─80)mg/L]间存在良好的线性关系,检测限为2.4μg/L,RSD=2.0%(n=8),并考察了人体内常见微量物质对的影响。  相似文献   

6.
乳清酸的单扫示波极谱研究   总被引:1,自引:0,他引:1  
乳清酸在0.1mol/LHClO4+0.02mol/LNaClO4底液中,于JP-2型示波极谱仪上,有一良好的二阶导数峰Ep=-0.860±0.01V(SCE),浓度在1×10-7~6×10-5mol/L范围内,与峰高成线性关系,检测限为7.5×10-8mol/L.实验证明,电极过程为具有催化性质的双电子可逆过程.  相似文献   

7.
本文调查了内蒙古包头市青山区8~10岁儿童碘缺乏病甲状腺肿大率,结果表明,甲状腺肿大率为19.6%,且以城乡结合部居住儿童为高;监测了其尿碘,尿碘水平100ug/L,以下者为12.7%,其中500mg/L者也有发现。据此情况,今后仍要强化防治工作。  相似文献   

8.
螺旋霉素药渣是制药工业的废弃物。本研究采用化学和生物化学方法,经酸、碱、盐和酶等水解分离,从药渣中提取蛋白质,对每种反应剂,利用正交设计试验,确定其最佳化学反应剂及分离方法,试验结果表明,蛋白质的平均溶出率为:酶法为51.37g/L,碱法为45.00g/L,酸法为29.45g/L,盐溶法为23.90g/L。蛋白质平均提取率为:酶法为60.77%,碱法为48.75%,酸法为24.6%,盐溶法为25.  相似文献   

9.
家鼠型EHFV台41株在沙鼠肾原代细胞上产生血凝素的研究   总被引:1,自引:0,他引:1  
研究结果表明,家鼠型EHFV台41第四代细胞传代株在沙鼠肾原代细胞上测得病毒TCID_(50)为10 ̄(6.5)/ml,血凝素滴度达1:512.影响血凝素滴度的主要因素有单层细胞的密度,病毒的接种量,血凝素收获的时间和血凝的最适pH值。  相似文献   

10.
谢尔凡 《科技通报》1998,14(2):79-83
观察了烟雾吸入后大鼠细胞内、外肺表面活性物质(PS)含量的变化及可能机理.分别检测了正常对照及烟雾致伤大鼠伤后2、6、12和24h的动脉血气、肺水量、血浆内皮素-1(ET-1)含量、支气管肺泡灌洗液(BALF)和肺匀浆总磷脂(TPL)含量、肺组织内板层体(LB)表达及肺泡Ⅱ型上皮细胞内LB平均数等.结果发现:动物伤后出现急性呼吸衰竭和严重肺水肿;血浆ET-1和BALF中TPL进行性升高,二者相关显著;肺组织和全肺TPL显著降低,LB表达及LB平均数明显减少,且与肺组织TPL的变化明显相关.提示烟雾吸入伤早期肺泡腔中细胞外PS增加,ET-1在介导PS持续分泌中可能有重要作用;细胞内及全肺PS减少,除分泌亢进外,可能还有合成障碍和(或)降解增加  相似文献   

11.
纳米氧化锌对人肺腺癌细胞A549的毒性   总被引:3,自引:0,他引:3  
探讨纳米氧化锌(ZnO)对体外培养的人肺腺癌细胞A549的生物学效应。使用原子力显微镜(AFM)、透射电镜(TEM)和X射线衍射仪(XRD)研究纳米ZnO颗粒物的理化性质。然后,使用0mmol/L、0.1mmol/L、0.5mmol/L、1mmol/L、5mmol/L、10mmol/L的纳米ZnO处理体外培养的人肺腺癌A549细胞,MTT 法测定细胞生长活性。并且测定1mmol/L 纳米ZnO染毒24h后细胞培养液上清中,乳酸脱氢酶(LDH)和胞内的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)的活性以及丙二醛(MDA)的含量。使用透射电镜和流式细胞仪检测细胞凋亡的情况。荧光染色检测细胞产生活性氧(ROS)的生成。实验所用的ZnO纳米颗粒为长75 nm、直径20nm的针状纤锌矿晶体。细胞实验结果表明,纳米ZnO颗粒对A549细胞的生长活性具有明显的抑制作用,存在剂量-效应关系。培养液上清中LDH活性显著升高(P < 0.05),胞内CAT活性显著下降、MDA含量显著升高(P < 0.01),但SOD活性下降不明显。荧光染色检测发现染毒后A549细胞出现细胞凋亡,而且细胞内ROS的生成与纳米ZnO存在剂量-效应关系。结论是纳米氧化锌诱导人肺腺癌A549细胞产生活性氧,引发细胞凋亡,并产生细胞毒性。  相似文献   

12.
采用盆栽法考察不同质量浓度的Cd、Zn、Cu、Pb、As 5种重金属复合胁迫对酢酱草抗氧化酶活性的影响。结果显示随着重金属处理浓度梯度的增加,酢酱草过氧化物酶(POD)活性、抗坏血酸过氧化物酶(APX)活性、脯氨酸(PRO)含量及谷胱甘肽(GSH)含量先升高后降低;而超氧化物歧化酶(SOD)活性和过氧化氢酶(CAT)酶活性逐渐下降。结果表明酢酱草在重金属复合胁迫下能防御性的增加POD酶活性、SOD酶活性、PRO含量及GSH含量以减少逆环境的伤害,而重金属复合胁迫浓度过高则会导致酢酱草抗氧化酶系统受到明显损害,生长受到很大程度的抑制。  相似文献   

13.
研究不同浓度钙离子对人成骨样细胞MG-63分化的影响.结果表明, 5.0mmol/L Ca2+促进 CaSR、ALP、OC、Runx 2、IGF-1和BMP2 mRNA表达,而加入CaSR和ERK抑制剂后,则下调 ALP、OC、Runx 2、IGF-1和BMP2 mRNA表达.不同浓度Ca2+处理后,磷酸化-ERK(p-ERK)蛋白表达明显增加.因此,5.0mmol/L Ca2+通过上调CaSR基因的表达,激活ERK通路,促进MG-63成骨样细胞的分化.  相似文献   

14.
Cholesterol and phospholipids were estimated in serum and bile from hepatic duct and gallbladder of twenty five patients of gallstone with functioning gallbladder (Group-I) and an equal number of patients having diseases other than of hepatobiliary system acting as control (Group-II). Group-I patients showed high serum cholesterol and low serum phospholipid levels as compared to those of Group-II. Cholesterol levels in hepatic duct and gallbladder bile were higher in Group-I than in Group-II whereas the phospholipid levels in the bile of Group-I were lower than in Group-II. The phospholipid: cholesterol ratios in hepatic duct and gallbladder bile of Group-I were 2.76 and 3.03 respectively as compared to 5.62 and 5.92 in Group-II.  相似文献   

15.
枇杷果肉制成丙酮粉,经硫酸铵分级沉淀、透析,DEAE-纤维素柱层析、ACA_(34)柱层析和FPLC分离等方法,分离和纯化得到多酚氧化酶的两个同工酶(酶A和酶B).酶B由一个或几个分子量为42×10~3D的亚基组成.酶的动力学研究表明:酶A、酶B的K_m(多巴胺为底物)均为2.40×10~(-3)mol/L,以邻苯二酚为底物时,酶A和酶B的K_m分别为0.163×10~(-3)mol/L和1.54×10~(-3)mol/L.酶底物特异性表明,酶B是邻位二酚酶,不能作用于单酚和间位二酚.  相似文献   

16.
A 40 days old male baby born to a consanguineous couple was found to have highly viscous and milky serum with caking of chylomicrons on refrigeration of serum. Cholesterol was 889.5 mg/dl (23.04mmol/L) and Triglycerides 12881 mg/dl (141.69mmol/L). He was active and did not have any hepatospleenomegaly, xanthomas or dysmorphic features. Thyroid functions were normal. Lipid electrophoresis showed thick chylomicron band. There was positive family history of hypertriglyceridemia in a first cousin. Both siblings and both parents of the index case had normal lipid profiles. This child was referred to higher centre where he was put on Lipid lowering drugs (Gemfibrozil), Iron drops and special formula for feeding containing medium chain fatty acids.  相似文献   

17.
This study reports the utilization of serum fructosamine and blood glucose for the screening of gestational diabetes mellitus (GDM). Blood samples from 165 pregnant women were analyzed for fasting blood glucose (FBG), random blood glucose (RBG) and serum fructosamine. The actual fructosamine levels were corrected for serum protein (c-Fruct) for more precise presentation. Two cut-off values of FBG (>5.3 mmol/L and >7.0 mmol/L) and RBG (>7.8 mmol/L and >11.0 mmol/L) were used to classify hyperglycemic subjects for subsequent evaluation. The average values±standard deviations for FBG, RBG and cFruct were 5.865±1.95, 7.767±3.21 and 2.387±0.47 mmol/L, respectively. FBG levels were significantly correlated with RBG (Pearson correlation=0.597, P<0.001). Significant correlations were also observed between cFruct and FBG (Pearson correlation=0.673, P<0.001) or RBG (Pearson correlation=0.641, P<0.001). Out of 165 subjects, 24 (14.5%) cases were classified as hyperglycemic on the basis of FBG>7.0 mmol/L or RBG>11.0 mmol/L; use of lower cut-off values resulted higher frequencies of hyperglycemia. Whereas, a combined criteria of FBG>5.3 mmol/L and cFruct >2.5 mmol/L predicted 35 patients as the most probable hyperglycemic as compared to 32 patients identified using the criteria of RBG >7.8 mmol/L and cFruct >2.5 mmol/L. These criteria were associated with 4.8% and 3.6% false-positivity at the expense of 3.6% and 3.0% false-negative outcomes, respectively. The levels of FBG, RBG and cFruct were significantly higher in hyperglycemic groups (irrespective of grouping criteria) as compared to the respective normal groups. In conclusion, these findings clearly indicate that the paired values of cFruct with FBG or RBG could help in filtering high-risk individuals for OGTT and therefore avoiding a unnecessary OGTT.  相似文献   

18.
Rats administered antibiotics showed increased hepatic cholesterogenesis as was evident from the increased activity of HMG-CoA reductase and increased incorporation of labelled acetate into liver cholesterol. But hepatic degradation of cholesterol to bile acids was decreased. There was increased release of lipoproteins into the circulation but their clearance from the circulation was lower as was evident from the decreased activity of lipoprotein lipase of the extrahepatic tissues. Activity of plasma LCAT was also decreased.  相似文献   

19.
IntroductionMost laboratories routinely determine haemolysis, icterus and lipemia indices to identify lipemic samples and reject potentially affected results. Hypertriglyceridemia is the most common cause of lipemia and severe hypertriglyceridemia (≥ 11.3 mmol/L) is a major risk factor of acute pancreatitis.Laboratory analysisA 56-year-old woman attended the outpatient clinic for a follow-up visit 1 month after a kidney transplantation. Her immunosuppressive therapy consisted of corticosteroids, cyclosporine, and mycophenolic acid. The routine clinical chemistry sample was rejected due to extreme lipemia. The comment “extreme lipemic sample” was added on the report, but the requesting physician could not be reached. The Cobas 8000 gave a technical error (absorption > 3.3) for the HIL-indices (L-index: 38.6 mmol/L) which persisted after high-speed centrifugation. The patient was given a new appointment 2 days later. The new sample was also grossly lipemic and gave the same technical error (L-index: 35.9 mmol/L).What happenedThe second sample was manually diluted 20-fold after centrifugation to obtain a result for triglycerides within the measuring range (0.10–50.0 mmol/L). Triglycerides were 169.1 mmol/L, corresponding to very severe hypertriglyceridemia. This result was communicated to the nephrologist and the patient immediately recalled to the hospital. She received therapeutic plasma exchange the next day and did not develop acute pancreatitis.Main lessonThis case illustrates the delicate balance between avoiding the release of unreliable results due to lipemia and the risk of delayed diagnosis when results are rejected. Providing an estimate of the degree of hypertriglyceridemia might be preferable to rejecting the result.  相似文献   

20.
A simple and reproduciable method for determining guanine by high performance capillary electrophoresis is presented. The method involved the use of 2-amino-5-mercapto-3,4-dithiazole as internal standard and 40mmol/L borax-H3PO4 (pH2)-5% EtOH as.the background electrolyte. The result showed that the linear range for guanine is 5-300 mg/L with the recovery of 94%-98% , the detection limit of 2. 80 mg/L and the RSD of 3. 1%. The satisfactory result was obtained when it was used to detect the concentration of guanine in acyclovir product.  相似文献   

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