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1.
江浙产蝮蛇毒提取的抗凝成份激活人血浆蛋白C的作用(摘要)瞿国伟,顾肃敏,黄美华,任彤,邵慧珍1.浙江医科大学2.上海市瑞金医院本文从江浙产蝮蛇粗毒中提取到的抗凝成份(SVPA),具有激活人血浆蛋白C活性,利用被激活的蛋白C特异性地分解生色底物而生成颜...  相似文献   

2.
采用高效液相色谱(HPLC)和荧光偏振技术测定了42例正常人红细胞膜和血浆游离脂肪酸(FFA)及膜微粘度,并探讨了膜脂肪酸和血浆FFA构成与膜微粘度之间的关系。结果表明:正常人红细胞膜主要由廿二碳六烯酸(C22∶6)、花生四烯酸(C20∶4)、亚油酸(C18∶2)、软脂酸(C16∶0)、油酸(C18∶1)和硬脂酸(C18∶0)等六种脂肪酸组成。血浆FFA构成与膜脂肪酸相似,但不含C22∶6而含十四烷酸(C14∶0)。红细胞膜各脂肪酸含量大多与其血浆浓度呈明显正相关。红细胞膜微粘度与膜软脂酸和硬脂酸呈明显正相关,与膜廿二碳六烯酸和花生四烯酸呈明显负相关。提示红细胞膜脂肪酸组成受血浆FFA成分影响;而红细胞膜脂肪酸成分对膜微粘度亦有重要影响  相似文献   

3.
许涛  钱琛  汪远金 《生物学杂志》2000,17(6):24-24,23
用腺嘌呤复制动物性慢性肾功能衰竭(CRF)模型。观察大鼠血浆血尿素氮(BuN)、血肌酐(Cr)、血红蛋白(Hb)、超氧化物歧化酶(SOD)和中分子物质(MMS)总量的变化。结果表明,CRF大鼠血浆BuN、Cr和MMS总量明显升高(P〈0.01)、Hb和SOD含量显著降低(P〈0.01)。提示CRF大鼠MMS总量升高、SOD活性降低。  相似文献   

4.
关于血清 Cu,Zn及 CuZn-SOD 与恶性肿瘤关系的探讨   总被引:4,自引:0,他引:4  
本文用原子吸收光度法,Oyangui法及AdachiY法分别测定了正常人与五种肿瘤患者血清Cu,Zn含量,铜锌超氧化物歧化酶(CuZn-SOD)的活性以及谷胱甘肽硫转移酶(GST)的活性。结果表明:恶性肿瘤患者血清中铜含量升高,锌含量降低,CuZn-SOD活性降低,而GST活性在正常人与肿瘤患者间无显著差异(P>0.05)。提示人血清中高铜,低锌,高铜/锌比值,以及CuZn-SOD活性降低与恶性肿瘤的发生有关。  相似文献   

5.
几种扩血管多肽对bFGF促血管平滑肌细胞增殖作用的影响   总被引:3,自引:0,他引:3  
目的和方法:研究肾上腺髓质素(Adm)、降钙素基因相关肽(CGRP)及C-型心房利太(CNP)对碱性成纤维细胞生长因子(bFGF)促血管平滑细胞(VSMC)增殖作用的影响及其机制。结果:孵育24h后,bFGF刺激VSMC增殖较对照组增加2.1倍(P〈0.01),细胞内蛋白磷酸化程度增加1.4倍(P〈0.01),PKC及MAPK活性分别增加1.5和2.5倍(P〈0.010;Adm.CGRPt CNP  相似文献   

6.
用四氮唑蓝光化学还原法对所合成的KCu(IDA)(Ser)·2H2O、KCu(IDA)(Ala)·H2O、Cu(IDA)(en)、KCu(IDA)(Gly)·H2O和Cu(IDA)·2H2O(IDA=N(羧基甲基)-甘氨酸,Ser=丝氨酸,Ala=丙氨酸,en=乙二胺,Gly=甘氨酸)等5种氨基酸─铜(Ⅱ)配合物进行了活性测定,发现它们均具有天然超氧化物歧化酶活性,其活性依次为0.34、0.45、0.50、0.54、0.72Cuμmol·L-1。  相似文献   

7.
测定了伴刀豆球蛋白(ConcanavalinA)和DIDS对人红细胞带3蛋白活性及结构的影响。(1)ConA使带3转运速度常数K显著增加。ConA浓度达到0.05mg/ml时,K值增加34.4%。DIDS对带3活性有明显的抑制作用。(2)荧光探针DPH,3AS,9AS,16AP分别测定ConA和DIDS与带3结合后膜流动性的变化。ConA能明显增加膜脂的流动性,而DIDS则降低膜脂流动性。(3)差示扫描量热法(DSC)测定带3蛋白变性性质,发现ConA使红细胞膜上带3蛋白变性峰出现温度从69.25°C减小到66.25°C,而DIDS则使之增至79.5°C。  相似文献   

8.
本实验测定了大鼠长时间游泳后即刻及恢复中尿中总蛋白(TP)、白蛋白(Alb)、β微球蛋白(β_2-mG)排泄率及血浆血管紧张素Ⅱ(AⅡ)活性,分析了AⅡ与尿蛋白组分排泄率的相关性。结果表明:AⅡ活性与Alb排泄率相关性较高(r=0.66,P<0.05),AⅡ活性与TP、β_2-mG排泄率相关性较低(r=0.42,P>0.05;r=0.34,P>0.05)。提示AⅡ活性在运动后尿蛋白产生机制中与大分子量的Alb排泄有较直接关系,而与TP及小分子量的β_2-mG排泄无明显直接关系。  相似文献   

9.
本文观察了溶血磷脂酸(LPA)对心肌细胞内蛋白激酶C(PKC)分布的影响。在离体家猫心脏灌流LPA(10-8mol/L)后差速离心分别制备心肌细胞胞浆、核及肌膜,测定各部分PKC活性。结果显示:与对照组比较,LPA组心肌总PKC活性增加9.8%(P<0.05),但胞浆PKC活性降低10.3%(P<0.05),膜与核的活性分别增加38.8%和77.6%(P<0.01)。结论:LPA刺激心肌细胞PKC活性增强,并可能使PKC从胞浆向胞核和肌膜部分转移  相似文献   

10.
兴奋下丘脑弓状核神经元降低大鼠血浆唾液酸水平的作用   总被引:5,自引:1,他引:4  
陈文芳  陈家津 《生理学报》1995,47(6):597-600
实验采用下丘脑弓状核(ARC)区微量注射和紫外分光光度测定法,研究ARC区注射不同浓度谷氨酸钠(Glu)对大鼠血浆唾液酸(SA)水平的影响。结果表明:(1)ARC区注射Glu后,血浆SA水平较对照组明显降低(P〈0.01),而且随Glu浓度的增加,血浆SA水平降低所需的时间逐渐缩短;(2)侧脑室注射阿朴吗啡后,ARC区注射Glu,血浆SA水平明显降低(P〈0.01),而且降低发生时间较对照组提前:  相似文献   

11.
Creatine has been quantified in various tissues by a range of methodologies. This paper reports on the development and validation of a simplified HPLC assay to determine plasma creatine, plasma protein binding of creatine, creatine in microdialysate and creatine in over-the-counter products. An isocratic, reversed-phase (C(18)) HPLC assay, using potassium phosphate monobasic (pH 4) as a mobile phase, was validated in human plasma and microdialysis perfusion fluid (normal saline). The lower limit of quantification for the assay was 1 mg l(-1) in saline and 5 mg l(-1) in plasma. The RSD was below 6% and accuracy was below 12% in both matrices. Protein binding in human plasma was found to be negligible (<10%). Over-the-counter creatine monohydrate products tested contained 100% creatine monohydrate. This assay was found to be suitable for pharmacokinetic studies and the assessment of plasma creatine and skeletal muscle microdialysate.  相似文献   

12.
A sensitive and specific protein binding assay for activin A/EDF (activin) was developed using follistatin as a binding protein and [125I] labelled activin as a tracer. As 50% acetonitrile (CH3CN) separated free and follistatin-bound activin, plasma pretreated with an equal volume of CH3CN was used as the assay sample and B/F separation was also done with 50% CH3CN. The recovery of the assay was 85.0% and its sensitivity was 0.5 ng/ml. Crossreactivity with inhibin A was 1.8%. The mean plasma level of follistatin-free activin in normal subjects was 1.3 +/- 0.7%. (M +/- SD) ng/ml. Plasma free activin levels were generally elevated in patients with chronic renal failure or hematological diseases associated with anemia.  相似文献   

13.
Acid sphingomyelinase (ASM; sphingomyelin phosphodiesterase, EC 3.1.4.12) is the lysosomal enzyme that hydrolyzes sphingomyelin (SPM) to phosphorylcholine and ceramide. An inherited deficiency of ASM activity results in Types A and B Niemann-Pick disease (NPD). In this study we report a new assay method to detect ASM activity and diagnose NPD using the fluorescent substrate BODIPY C12-SPM and reverse-phase high-performance liquid chromatography (HPLC). The reaction product, BODIPY C12-ceramide (B12Cer), could be clearly and efficiently separated from the substrate within 4 min using a reverse-phase column (Aquasil C18, Keystone Scientific). Femtomole quantities of B12Cer could be detected in as little as 1.0 micro l of human plasma, providing a sensitive measure of ASM activity. The mean ASM activity in human plasma from NPD patients (36 pmol/ml/h) was only 2.7% of that in normal plasma (1334 pmol/ml/h), confirming the specificity and diagnostic value of this new assay method. Importantly, the mean ASM activity in human plasma from NPD carriers (258.3 pmol/ml/h) also was significantly reduced (19.5% of normal). The ranges of ASM plasma activities in NPD patients (N=19), NPD carriers (N=11), and normal subjects (N=15) were 2.5-97.3, 108-551, and 1030-2124 pmol/ml/h, respectively. Based on these results, we suggest that this fluorescence-based HPLC assay method is a reliable, rapid, and highly sensitive technique to determine ASM activity and that plasma is a very reliable and simple source for the accurate diagnosis of NPD patients and carriers based on ASM activity.  相似文献   

14.
We studied the use of high-performance liquid chromatography (HPLC) with spectrofluorometric detection, using a solid-phase extraction for a simple, rapid and sensitive determination of plasma carvedilol levels in rats. Extracted aliquots were analyzed by HPLC, using a reversed-phase octadecyl silica column. The analytical mean recovery of carvedilol added to the blank plasma was 94.2%. The detection limit was 3.6 ng/ml in the plasma. The reproducibilities (C.V.) were 2.7–7.5% for the within-day assay, and 2.6–7.4% for the between-day assay, indicating that the method was effective for the determination of carvedilol plasma levels.  相似文献   

15.
A rapid and sensitive liquid chromatography/mass spectrometry (LC/MS) method was developed and validated for the determination of rimantadine in rat plasma. Rimantadine was extracted by protein precipitation with methanol, and the chromatographic separation was performed on a C(18) column. The total analytical run time was relatively short (4.6 min), and the limit of assay quantification (LLOQ) was 2 ng/mL using 50 microL of rat plasma. Rimantadine and the internal standard (amantadine) were monitored in selected ion monitoring (SIM) mode at m/z 180.2 and 152.1, respectively. The standard curve was linear over a concentration range from 2 to 750 ng/mL, and the correlation coefficients were greater than 0.999. The mean intra- and inter-day assay accuracy ranged from 100.1-105.0% to 100.3-104.0%, respectively, and the mean intra- and inter-day precision was between 1.3-2.3% and 1.8-3.0%, respectively. The developed assay method was successfully applied to a pharmacokinetic study in rats after oral administration of rimantadine hydrochloride at the dose of 20 mg/kg.  相似文献   

16.
We describe a method for the measurement of plasma dehydroepiandrosterone sulphate (DHAS) which incorporates a Triton X-100 solubilised preparation of human placental steroid sulphatase as a hydrolysing agent and a direct radioimmunoassay of liberated DHA using a specific antiserum. The hydrolysis procedure is carried out at 50 degrees C for 1 h and an assay run can be completed in 4 h. As determined by the method, plasma concentrations of DHAS in 32 normal adult men (ages 23-58 yr) had a mean value +/- SD of 5.5 +/- 1.89 mumol/l. For 30 normal adult cyclic women (ages 22-35 yr) the mean plasma concentration of DHAS +/- SD was 3.1 +/- 1.35 mumol/l which was significantly lower (P less than 0.01) than found for men. Plasma DHAS concentration were also measured in 50 hirsute female patients. The mean value +/- SD was 5.03 +/- 2.52 mumol/l which was significantly higher (P less than 0.01) than the value for the normal female group. Some 42% of the hirsute patients had DHAS concentrations above the upper 95% probability limit of the normal range for premenopausal women.  相似文献   

17.
Terbutaline is a beta-adrenergic receptor antagonist that acts as a bronchodilator in the treatment of asthma and chronic bronchitis. In the present work, a column-switching high-performance liquid chromatographic method was developed to monitor terbutaline sulphate in dog plasma. The system consists of a C2 pre-column (PC) and a C18 analytical column connected in series via a switching valve. Atenolol was used as the internal standard. Good linearity was achieved in the range of 5-800 ng/ml plasma. The mean intra- and inter-assay variation coefficients for this analysis were 2.3 and 4.7%, respectively. The average recovery for terbutaline was 87.4% from plasma. The mean concentration after three freeze-thaw cycles was 99.4% of the normal value. The analytical sensitivity and accuracy of this assay is adequate for characterisation of the pharmacokinetics of oral administration of terbutaline to dogs and has been successfully used to provide pharmacokinetic data using pulsatile and immediate-release tablets.  相似文献   

18.
Dog polymorphonuclear leukocyte cathepsin G was isolated from a granule extract using a two-step procedure including affinity chromatography on a Trasylol-Sepharose gel and ion-exchange chromatography on a CM 52 column. 22 of the first 24 N-terminal amino acids were determined and showed 83% and 71% identity to those of human and rat cathepsin G, respectively. Total amino-acid composition demonstrated the basic nature of the protein. In an SDS/polyacrylamide-gel electrophoresis the protein showed an Mr of 29,400 compared to the Mr of 26,800 calculated from the total amino-acid composition. The enzyme was shown to form complexes with alpha 1 alpha 2-macroglobulin and alpha 1-proteinase inhibitor. A specific enzyme-linked immunosorbent assay was developed for the determination of cathepsin G/alpha 1-proteinase inhibitor complex in dog plasma and tissue fluids. The mean concentration of cathepsin G in normal dog plasma was determined to be 38 micrograms/l, measured as cathepsin G/alpha 1-proteinase inhibitor complex. When active dog cathepsin G was added to normal dog plasma in vitro, approximately 56% could be measured by the assay. Slow intravenous infusion of a lethal dose of endotoxin in dogs was followed by a marked drop in white blood cell count and thrombocytes and a simultaneous rapid increase in plasma cathepsin G concentration, reaching a maximum level of 150 micrograms/l. Bile-induced experimental pancreatitis in dogs was accompanied by successive increase in cathepsin G levels in plasma as well as in peritoneal exudates, reaching a maximum level of about 300 micrograms/l in plasma and 18 mg/l in the exudates during the late stages of disease.  相似文献   

19.
Paclitaxel is pharmaceutically formulated in a mixture of Cremophor EL and ethanol (1:1, v/v). The unbound fraction of the anticancer drug paclitaxel in plasma is dependent on both plasma protein binding and entrapment in Cremophor EL micelles. We have developed a simple and reproducible method for the quantification of the unbound paclitaxel fraction in human plasma. Human plasma was spiked with [3H]paclitaxel and [14C]glucose (unbound reference) and incubated at 37 degrees C for 30 min. Plasma ultrafiltrate was prepared by a micropartition system (MPS-1) and collected in a sample cup containing 100 microl of plasma to prevent the loss of paclitaxel due to adsorption. The radionuclides were separated after combustion of the biological samples using a sample oxidizer and the radioactivity was determined by liquid scintillation counting. The unbound fraction of paclitaxel was calculated by dividing the ratios of 3H and 14C in plasma ultrafiltrate and in plasma. The method was thoroughly validated using human plasma spiked with pharmacologically relevant concentrations of paclitaxel (10-1000 ng/ml) and Cremophor EL (0.25-2.0%). The method was precise, with a within-day precision ranging from 3.9 to 11.0% and a between-day precision ranging from 5.8 to 13.1%. In patient plasma with low serum albumin values containing 1% of Cremophor EL, the unbound fraction appeared to be significantly higher than that in plasma with normal albumin values. The determination of the unbound fraction of paclitaxel proved to be stable during a 10-week storage at -20 degrees C. Furthermore, the assay was applicable in patient samples. This assay can be used to determine the unbound fraction of paclitaxel in plasma. Moreover, its design should allow the determination of the unbound concentrations of other hydrophobic drugs.  相似文献   

20.
A highly sensitive and specific RIA for IGF-I has been developed using recombinant DNA-derived IGF-I of very high purity and specific antiserum to it. This assay system could detect IGF-I at as low concentrations as 20-30 ng/ml. The intra-assay and interassay coefficients of variation at various concentrations of IGF-I were 4.9 to 6.5% and 5.4 to 8.0%, respectively. The recovery rate of pure IGF-I added to plasma was 77.0 +/- 3.7%. The antiserum did not cross-react with porcine insulin, biosynthetic human insulin, hGH, hEGF, the synthetic C-domain of IGF-I or that of IGF-II, but reacted equally with an analog, Thr59-IGF-I. Plasma IGF-I was extracted by the acid-ethanol method before assay to separate IGF-I from its binding protein. When plasma IGF-I was assayed without extraction, the inhibition curves of serial dilution of plasma samples from several individuals were not parallel to the standard curve of IGF-I. The plasma concentration of IGF-I was 147 +/- 49 ng/ml (mean +/- SD) in 156 normal adults aged from 20-59 years. As reported by others, the IGF-I levels were low in cord plasma (41.8 +/- 23.5 ng/ml) and plasma of patients with GH deficiency (64.6 +/- 42.0 ng/ml), while its levels were high in normal children of pubertal ages (12-13 yr, 365 +/- 126 ng/ml) and in patients with active acromegaly (562 +/- 115 ng/ml). This RIA system is a simple and useful method for determining plasma IGF-I in normal and diseased states.  相似文献   

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