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51.
Summary: Matrix metalloproteinases (MP) are important candidates for the degradation of extracellular matrix, but the role of MP in the diseased kidney remains poorly understood. to examine the significance of urinary MP, we first investigated the characteristics of MP in normal rat urine and renal cortex, and then evaluated the urinary MP activity in anti-thymocyte induced glomerulonephritis (Thy.1 GN). Metalloproteinase activity was measured as the EDTA-inhibitable degradation of [3 H] gelatin. the enzyme was purified from urine and the renal cortex homogenate in normal Wistar rats by using several chromatographic and gel filtration methods. Both materials contained the identical molecular weight (Mr 126 kDa by gel permeation method) of gelatin-degrading enzymes, the activity of which was inhibited by metal chelating agents and reactivated by ZnC12 but not by other proteinase inhibitors. Thy.1 GN was induced by intravenous injection of rabbit anti-thymocyte serum into rats, and daily urine was collected at sequential time points. Urinary MP activity was markedly reduced soon after the serum injection, and returned to the control level in 9 weeks. Conversely, urinary MP-inhibitor activity (Mr 30 kDa), determined as inhibiting activity against MP derived from renal cortex, showed serial changes strikingly reflected as urinary MP activity. These findings suggested that rat urine contained the MP which seemed to be derived from the renal cortex, and the urinary MP activity was decreased in Thy.1 GN model, probably due to the presence of MP-inhibitor. As urinary MP is likely to reflect intra-renal MP, the evaluation of urinary MP may be useful to search metabolic alteration of extracellular matrix in the diseased kidney. 相似文献
52.
目的:探讨可溶性细胞间粘附分子-1在妊娠期高血压疾病患者血浆中的变化,为临床诊治提供依据。方法:用ELISA法检测29例妊娠期高血压疾病患者血浆中可溶性细胞间粘附分子-1水平,并与正常妊娠组和正常对照组进行组间比较。结果:子痫前期组、妊娠期高血压组、正常妊娠组晚期及正常对照组的可溶性细胞间粘附分子-1水平分别为1129.82±399.16、794.35±255.57、661.51±301.79及549.23±139.98ng/ml。组间比较,子痫前期组与妊娠期高血压组之间P<0.05,与正常妊娠组晚期及正常对照组之间P<0.001;妊娠期高血压组与正常对照组之间P<0.001;妊娠期高血压组与正常妊娠组晚期相比P>0.05,正常妊娠组3个不同孕龄阶段P>0.05。结论:可溶性细胞间粘附分子-1在妊娠期高血压疾病时显著升高,并随病情的加重而增高,可作为该病诊断和监控的一项指标。 相似文献
53.
54.
Dr. S. K. Gupta J. C. Ritchie E. H. Ellinwood K. Wiedemann F. Holsboer 《European journal of clinical pharmacology》1992,43(1):51-55
Summary Changes in time course effected by cortisol suppression and the relationship of these changes to the plasma dexamethasone concentration of suppressor and non-suppressor patients are described in this report on a combined pharmacokinetic-pharmacodynamic model.Thirteen depressed patients (8 suppressors and 5 non-suppressors) received an intravenous dose (1.5 mg) of dexamethasone. The drug-induced effect changes are found to lag behind, in time, the plasma drug level changes. To accurately relate the temporal relationship of effect changes to plasma dexamethasone levels, a pharmacodynamic model (sigmoid-Emax) was combined with a pharmacokinetic model that incorporated an effect compartment. The magnitude of the time-lag was quantified by the half-time of equilibration between concentrations in the hypothetical effect compartment and the plasma dexamethasone levels (t&frac;keo).The t&frac;keo of the nonsuppressing group was about 50 of that of the suppressing group, indicating that for a given plasma level the onset and termination of effect for the nonsuppressing group is about two times more rapid than for the suppressing group. Moreover, the model can estimate the effect-site concentration that causes one-half of the maximal predicted effect (EC50), a measure of an individual's sensitivity to dexamethasone. The receptor sensitivity (as determined from the EC50 ratio) of the suppressing group was about twice that of the nonsuppressing group. 相似文献
55.
近年来的研究结果发现由Th1/Th2细胞分泌的淋巴因子与妊娠高血压综合征联系密切 ,可能参与了其病因及病理生理过程 ,对它的深入研究有利于妊娠高血压综合征诊断、治疗水平的提高 相似文献
56.
目的研究与细胞因子信号转导等相关的病理基因在妊娠高血压综合征(妊高征)胎盘组织中的表达变化.方法采用分别包含220余种人类细胞因子相关基因或人类环境激素相关基因cDNA片段的基因芯片,检测严格配伍的正常和妊高征胎盘组织中基因表达谱的差异.结果一些疾病相关基因(GenBank:U82828、X15183)在妊高征患者胎盘中的表达高于正常,另外一些与基因表达调控有关的转录因子基因(GenBank:AL022312、M15990、U15009、L49380等)也表达增强.此外,妊高征胎盘中与细胞因子信号转导有关的大多数受体/激酶表达增强,例如GenBank登录号为M76125、U73531、L76191、L06139、AF035121、M23379、U43195等基因.结论细胞因子信号转导相关基因等的表达增强提示细胞因子的功能活跃,进一步说明胎盘局部细胞因子水平的变化与妊高征的病理发生密切相关. 相似文献
57.
58.
【目的】比较宫颈Bishop评分和宫颈胰岛素样生长因子结合蛋白 1(IGFBP 1)检测在妊娠晚期气囊助产中的临床意义。【方法】将妊娠晚期有引产指征的 15 0例初产妇随机分成 3组 ,每组 5 0例。A组在气囊助产前使用宫颈IGFBP 1检测作为引产时机预测 ,B组在气囊助产前使用宫颈Bishop评分作为引产时机预测 ,C组则单纯催产素引产同时使用宫颈Bish op评分作为引产时机预测。【结果】总引产时间、潜伏期、活跃期、第一产程、第二产程 ,A、B两组较C组短 (P <0 0 1) ;A组总引产时间较B组短 (P <0 0 5 ) ;A组潜伏期、活跃期、第一产程、第二产程的较B组短 ,但差别无统计学意义 ;阴道分娩率A组 >B组 >C组 ,剖宫产率A组 相似文献
59.
正常妊娠和妊娠高血压综合征孕妇血清脂质的过氧化作用 总被引:1,自引:0,他引:1
目的 探讨脂质过氧化作用在正常妊娠时的生理和妊娠高血压综合征 (妊高征 )时的致病机制。方法 应用美国CIBA 5 6 0全自动生化分析仪及 72 2分光光度计对正常孕妇 178例、妊高征孕妇 2 4 6例、正常晚期孕妇 178例和正常未孕妇女 6 2例 (对照组 )的血清中SOD ,LPO ,NO及总抗氧化能力进行测定比较。结果 正常妊娠晚期的SOD活性及LPO水平高于非妊娠妇女 (P <0 .0 5 ) ,妊高征患者中脂质过氧化物水平显著高于同期正常妊娠水平 (P <0 .0 5 ) ,而且随病情严重程度而升高。妊高征患者NO水平低于正常妊娠妇女 (P <0 .0 5 )。NO水平随妊高征病情进展而逐渐降低。结论 SOD ,LPO ,NO的合成、释放在妊高征的病理变化中起重要作用 相似文献
60.
Summary. Superoxide dismutase-like activity (SOD-like), isoenzyme lactate dehydrogenase-C4 (LDH-C4) and NADH-diaphorase activities in spermatozoa have been investigated from 58 normozoospermic and 27 oligozoospermic men. Significantly higher SOD-like, LDH-C4 and diaphorase activities ( P <0.01, P <0.005 and P <0.0001, respectively) were detected in spermatozoa from oligozoospermic men, compared to the activities found in normozoospermic samples. SOD-like activity (mean±SE) in oligozoospermic samples amounted to 8.3±1.6 U 10−8 spermatozoa, while in spermatozoa in normozoospermic men with a sperm concentration above 20 million of spermatozoa per ml amounted to 4.2±0.5 U 10−8 . There was a close correlation between the SOD-like activity and biochemical indicators of the presence of residual cytoplasm i.e. isoenzyme LDH-C4 and NADH-diaphorase (r = 0.53 and r = 0.66 in normozoospermic and r = 0.63 and r = 0.54 in oligozoospermic men, respectively). A positive relationship between SOD-like activity and experimentally-induced lipid peroxidation was detected in 54 infertile men (r = 0.30; P <0.05). These findings suggest that a higher level of superoxide dismutase-like activity may reflect a defect in the development or maturation of spermatozoa and, thereby, a decreased fertility potential. Hence, determination of SOD-like activity may give information on the state of maturity of human spermatozoa, while its role in the antioxidative protection remains to be determined. 相似文献