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1.
应用免疫细胞化学染色技术,用抗心钠素血清对人胚胎发育不同时期的脐带血管进行免疫染色,观察结果:在第14周时脐动静内皮细胞即显阳性反应,并随胎龄增加而略微增强,至第32周时阳性反应明显增强达高峰,维持至出生。人脐动脉内皮细胞与人脐静脉内皮细胞之间存在明显差异。至于HUA/VEC及ANP是否参与对脐血管舒缩的调节,尚有待进一步实验证实。  相似文献   

2.
钒钼黄分光光度法测定有机化合物中的微量磷   总被引:2,自引:0,他引:2  
介绍了钒钼黄分光光度法测定有机化合物中微量磷的方法。有机磷经浓硫酸-硝酸氧化分解,转化为正磷酸。在一定酸度下,溶液中的磷与偏钒酸盐和钼酸盐作用,形成稳定的黄色三元杂多酸钒钼磷酸,再用分光光度法测定磷含量。  相似文献   

3.
分光光度法测定汽油中的磷   总被引:3,自引:0,他引:3  
提出了用磷钒钼酸分光光度法测定汽油中磷含量的方法,通过对汽油中可能存在的共存离子干扰进行了考察,确定了最佳测试条件。对合成标准样品分析,其相对误差小于±3.0%,相对标准偏差小于2.3%,对实际样品进行分析并进行了加标回收试验,磷回收率达到98.8%~103.9%。是一种快速、可靠测定汽油中磷含量的方法。  相似文献   

4.
5.
建立了一种在表面面活性剂Brij-35存在下,用2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚(5-Br-PADAP)作显色剂不去蛋白直接光度法测定血清锌的新方法.用该法测定血清锌,显色络合物最大吸收波长为560nm,线性范围0~46.0μmol.L-1,表观摩尔吸光系数为1.08×105L.mol-1cm-1,回收率为97.5%~102.8%,批内变异系数(CV)和批间变异系数分别为2.3%与3.7%.与原子吸收分光光度法比较具有良好的相关性.回归方程为y=1.01x-0.26,r=0.9884,P>0.05.4例健康人血清锌含量为9.5~24.7μmol.L-1(x-±2S).用该法进行血清锌测定,准确性和重现性均较好,且血清用量少,不必去蛋白,操作步骤简化,具有快速、简便、灵敏可靠等优点,适合临床应用.  相似文献   

6.
利用超高效液相色谱-飞行时间质谱技术(UPLC-Q-TOF-MS/MS)分析了黄颡鱼不同部位的脂质成分。采用甲醇-氯仿(1∶1,体积比)对血清、肌肉和肝脏进行脂质成分提取。液相色谱采用C8色谱柱,柱温40℃,流动相A为乙腈-甲醇-异丙醇(1∶1∶1),流动相B为乙腈-水(0.1%甲酸,0.01%氯化锂)。根据高分辨质谱获得精确分子量,推测出元素组成,并结合脂质成分的二级质谱裂解规律,在血清、肌肉和肝脏中共鉴定出85个脂质成分,主要有PC,Lyso-PC,PE,Lyso-PE,PI,PS,DAG,TAG,SM和Cer。在这3个部位中有19个共有脂质成分,包括Lyso-PC 16∶0,9个PC,3个PI,4个TAG和2个SM。此外PS和Lyso-PE仅在肌肉中鉴定出,分别为PS 18∶0/22∶6,Lyso-PE 16∶0和Lyso-PE 18∶1;神经酰胺仅在肝脏中观察到,为Cer(d18∶1/24∶1);而PE和DAG只在肌肉和肝脏中存在,在血清中未发现。该方法操作简单、灵敏、高效,为快速、全面了解黄颡鱼中的脂质分布提供了科学依据。  相似文献   

7.
建立了分光光度法测定磷系阻燃粘胶纤维中磷含量的方法,对测定条件进行优化。提出采用硫酸―过氧化氢湿法消解磷系阻燃粘胶纤维的消解体系,使用磷钼黄分光光度法测定磷含量。结果表明:在最优化条件下,磷元素在0.00 mg/L~10.0 mg/L范围内呈线性关系,相关系数为R~2=0.999 8,加标回收率为83.3%~111%,测定结果的相对标准偏差为2.0%~2.4%。该方法用于测定阻燃粘胶纤维中磷含量操作简单、快速、准确。  相似文献   

8.
曾百肇  廖亮 《分析化学》1995,23(8):915-918
在PH4的邻苯二甲酸氢钾缓冲溶液中,1,4-二巯基苏糖醇可较快地将磷钼黄还原成磷钼蓝。该反应对DTT为准一级反应,反应中DTT分子的两个巯基各失去一个电子,巯基失电子后相互结合成双硫链。该反应能定量进行,因此可用于DTT的间接光度测定,应用此方法测定DTT的适用范围为2.0×10^-6-1.0×10^-4mol/L。  相似文献   

9.
王胜天  丁兰  李景虹 《分析化学》2002,30(7):895-895
1 引  言流动注射分析 (FIA)用于实际样品中磷的测定已有许多文献报道 ,而有关合金中磷的测定很少见。杂多酸吸收光度法测定磷影响因素很多 ,用于合金分析比较困难。为此我们以栓塞铝合金为对象 ,对测定条件及干扰情况进行了详细研究。本方法可以有效地消除金属离子干扰 ,进样频率 6 0次 h,检测限为 0 .0 5mg L ,实际样品的测定结果令人满意 ,适合于大批量铝合金样品的测定。2 实验部分2 1 仪器与试剂 TRB型蠕动泵 (东北电力学院仪器仪表厂 ) ,配以适当规格的tygon泵管 ;72 1分光光度计 (四川分析仪器仪表厂 ) ,配以…  相似文献   

10.
对磷复肥中磷的分析,涉及水溶磷和枸溶磷的测定.传统的方法操作繁琐,周期长,不能满足生产需要[1~4,9~12].用磷钒钼法测定时,用于提取枸溶磷的柠檬酸或EDTA要产生严重的干扰,使得处理过程较为繁琐[1,2,5,7].  相似文献   

11.
This review summarizes the data on the synthesis of various phosphorus-and-sulfurcontaining organic compounds based on the reactions of elemental phosphorus and sulfur and their derivatives (various types of esters of trivalent phosphorus thioacids) with a variety of organic compounds. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1706–1711, October, 1993.  相似文献   

12.
Synthesis and applications of biscyclic phosphorus flame retardants   总被引:1,自引:0,他引:1  
The influence of structural effects of organo-phosphorus flame retardants (FRs) on their flame retardant action was investigated. A series of spirobisphosphorus compounds including 3,9-dibutyl-3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro-5,5-undecane were prepared using various synthetic methods such as the Arbuzov reaction. The chemical structure of the product was confirmed by 1H and 31P NMR. Thermogravimetric analysis (TGA) results reveal that these cyclic phosphorus compounds show a single step degradation in the range of 250-400 °C and act in the gas phase rather than in the condensed phase. The obtained products were blended with an acrylonitrile-butadiene-styrene copolymer (ABS) or polycarbonate (PC) and their flame retardant behavior was evaluated using a UL-94 vertical test. V-0 ratings are achieved at 15-35 wt% loading of FR for ABS and at a much lesser amount of loading for PC. In both cases, it is apparent that the flame retardancy is strongly dependent on the P content of the flame retardant.  相似文献   

13.
A method for the direct determination of pefloxacin in serum and pharmaceutical forms (tablets and ampoules) has been developed, based on the use of second-order derivative ultraviolet spectra. Spectrophotometric assay of pefloxacin in tablets and ampoules was carried out in 0.1 mol/L NaOH, while in serum it was performed in 0.1 mol/L NaOH with the addition of sodium dodecylsulfate, in 337–347 nm wavelength range. Linear calibration curves were obtained in the concentration ranges 2–30g/mL pefloxacin for tablets and ampoules and 0.12–5 g/ mL for serum samples. Relative error of determination, as criterion for accuracy, was less than 1%, while the precision was better than 4 ng/ml. The minimum detectable concentration of pefloxacin in serum was 15 ng/mL.  相似文献   

14.
杨凯歌  王薇薇  王彦  阎超 《色谱》2021,39(11):1191-1202
外泌体是由各种类型细胞在正常或非正常生理情况下分泌释放至细胞外且携带多种生物活性分子的细胞外囊泡,在细胞间通讯和免疫应答等生物过程中发挥着重要作用。肝内胆管癌是一种胆道上皮恶性肿瘤,早期无明显临床症状且生存率较低,目前常用的诊断手段包括依赖于影像设备的诊断方式和灵敏度及特异性较低的诊断标志物等,这些手段的不足对发展新的特异性标志物提出了需求。该文对血清中的外泌体进行了分离和表征,并采用液相色谱-质谱技术针对健康组与肝内胆管癌患者组的血清样本和血清外泌体样本进行了无标记定量蛋白质组学分析,分别从两种类型样本中鉴定并筛选到271和430种可信蛋白质。基于血清样本和血清外泌体样本的可信蛋白质定量表达值进行多维统计分析都能将健康组与肝内胆管癌患者组良好地区分开。对血清样本中鉴定到的蛋白质进行差异蛋白质筛选,肝内胆管癌患者组相对于健康组有15个上调和8个下调蛋白质;对血清外泌体样本中鉴定到的蛋白质进行差异蛋白质筛选,肝内胆管癌患者组相对于健康组有33个上调和18个下调蛋白质;基于两种样本筛选到的差异蛋白质中仅有4个是重复的,且基于血清外泌体样本的51个差异蛋白质中有35个蛋白质属于外泌体蛋白质数据库。针对差异蛋白质进行生物学信息分析,与差异蛋白质相关的分子功能、生物过程和信号通路主要涉及天然免疫反应、炎症反应和凝血等过程。该研究为发现肝内胆管癌的潜在生物标志物和探究肝内胆管癌的发生、发展和转移等过程提供了参考和借鉴价值。此外,通过比较研究发现血清外泌体样本能够获得较多的差异蛋白质和生物学信息,证明了外泌体作为组学分析样本的价值和应用潜力。  相似文献   

15.
The use of metal complexes containing phosphorus ligands as anticancer agents has not been well studied. In this work, eight novel half‐sandwich IrIII and RuII compounds with P^P‐chelating ligands have been synthesized and fully characterized, and alongside two crystal structures were reported. All eight complexes displayed highly potent antiproliferative activity, up to nine times more potent than the clinical anticancer drug cisplatin towards A549 lung cancer cells. Complex Ir1 , which has a simpler structure and highly potent antiproliferative activity, was selected to investigate in further mechanistic studies. No hydrolysis and nucleobase binding occurred for complex Ir1 . In order to elucidate subcellular localization, the self‐luminescence of the complex Ir1 was utilized. Ir1 can specifically target lysosomes and facilitate excessive production of reactive oxygen species, resulting in lysosomal membrane permeabilization in A549 cells. Release of cathepsin B and changes in the mitochondria membrane potential also contributed to the observed cytotoxicity of Ir1 , which demonstrated an anticancer action mechanism that was different from that of cisplatin. The favorable results from biological and chemical research demonstrated that these types of complexes hold significant theranostic potential.  相似文献   

16.
Multi-step procedures for the determination of phosphorus, sulfur and chlorine are described and tested against established methods and on reference materials. Phosphorus is separated as hydrogen phosphide, extracted as phosphomolybdic acid, reduced to molydenum blue and measured photometrically (detection limit 0.05 g/g). Sulfur is separated after reduction as hydrogen sulfide or by means of pyrohydrolysis and measured by ICP-OES (detection limit 0.1 g/g). Chloride can be measured by ion chromatography after pyrohydrolytic separation (detection limit 0.1 g/g). The determination of sulfur was also successfully tested on copper and steel samples.Dedicated to Professor Günther Tölg on the occasion of his 60th birthday  相似文献   

17.
In the presence of white phosphorus the redox potentials of the copper ions change and the potential of the reduction wave of CuI/Cu0 shifts noticeably toward more positive values. The CuI—P4 complex is characterized by a lower value of the electrochemical gap, that is, higher polarizability and reactivity compared to those of the free CuI cation. Phosphorus esters can be synthesized from P4 and ethanol. The latter is in the composition of the copper(ii) complexes, which act as a catalyst-charge mediator.  相似文献   

18.
A complete analytical procedure, including sample clean-up and a micellar electrokinetic chromatographic method, is presented for the determination of sulfamethoxazole, trimethoprim, and their main metabolites by using 20 mmol L(-1) borate buffer (pH 9.3), 25 mmol L(-1) sodium dodecylsulfate, and 5% v/v acetonitrile as electrolyte. The separation was carried out at 30 kV and 20 degrees C in a fused silica capillary (60.2 cm x 75 microm inner diameter) fitted with a window in the capillary cartridge of 100 x 800 microm. The detector response was linear from the limit of quantification to 3 mg L(-1) for the individual components. The limits of quantification ranged from 0.13 up to 0.24 mg L(-1). The method was applied to human serum, previously spiked at different concentrations of all the analytes, and recoveries between 95% and 108% were obtained.  相似文献   

19.
20.
Representative members from five different families of supported phosphine and phosphinite ligands have been prepared from common templates—polymer-bound aminoalcohols. These include β-aminophosphines, N,β-diphosphinoamines, α,β-diphosphinoamines, β-aminophosphinites and N-phosphino-β-aminophosphinites. Representatives of each family of ligands were complexed with Pd(OAc)2 and screened in the Heck reaction of iodo- and bromobenzene. While the reaction of iodoarenes is ligand-independent, the reaction of bromoarenes is ligand-sensitive. The rationale for this behavior is suggested. Lead ligands for the reaction of bromoarenes were determined.  相似文献   

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