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31.
Summary It has been suggested that urinary sialidase may play a role in the formation of renal stones. The present study was therefore undertaken to compare spectrophotometrically the different types of sialic acid concentrations and sialidase activities in fresh first morning urine specimens of men (21–65 years) with (13) and without (9) calcium oxalate renal stones. Although the free urinary sialic acid concentrations of the two groups of men were statistically about the same (P=0.0614), the total (P=0.003) and bound (P=0.0012) urinary sialic acid concentrations differed significantly. Both the total and bound sialic acid concentrations were lower in the urine specimens of the stone patients than in their healthy counterparts. This decrease in urinary sialic acid concentrations was firstly thought to be the result of elevated breakdown enzymes of sialic acid, which would favour the production of pyruvate. However, spectrophotometric determinations of the endogenous pyruvate concentrations of the two types of urine specimens did not differ significantly (P=0.0708). Secondly, the decrease in total urinary total sialic acid concentration of stone patients, could be attributed to less sialic acid synthesis or less renal excretion. Therefore, the same experiments were repeated using serum of 13 patients and 9 healthy men. Conversely, the total (P=0.4425) and bound (P=0.2850) serum sialic acid concentrations were found to be similar in the two types of subjects. However, the free serum sialic acid concentration of stone patients was significantly lower than in the healthy subjects (P=0.0062). This phenomenon is also reflected in the average ratio for serum free: bound sialic acid in healthy and stone patients, 1:7.9 and 1:18.7 respectively (P=0.0009). The lower free serum sialic acid concentration may lead to lower renal excretions of sialic acid. This may explain the decrease in total urinary sialic acid concentration in stone patients. The lower bound urinary sialic acid concentrations in patients was also reflected in the urinary free: bound sialic acid ratio for healthy (1:2.3) and stone patients (1:1.3). The difference between these two groups of men was highly significant (P=0.0001). This phenomenon might be explained by the urinary sialidase activities, which was spectrophotometrically determined at 334 nm at 37°C of 11 patients with stones and 17 healthy men. The ages of both groups of men were the same (P=0.326). An increase in urinary sialidase activity was observed with the stone patients (P=0.00001) when compared to specimens of healthy men. This might explain the decrease in urinary bound sialic acid concentration of the stone group. It seems from these results that the urinary concentration of sialic acid and the activity of urinary sialidase, may play a role in the pathogenesis of the multifactorial disease, urolithiasis.  相似文献   
32.
目的:探讨血管内皮细胞生长因子(VEGF)在子宫肌瘤发生和肌瘤生长中的作用。方法:手术中暴露子宫静脉后,抽取子宫静脉血3ml,同时抽取非输液肢体外周静脉血3ml。抽取配对正常妇女外周静脉血3ml。ELISA法测定VEGF水平。测量子宫重量、肌瘤总重量、肌瘤数目和最大肌瘤最大径线值。结果:子宫肌瘤患者子宫静脉血和外周静脉血VEGF水平分别为159.38±25.63pg/ml和76.35±26.61pg/ml,对照人群外周静脉血VEGF水平为42.53±29.47pg/ml。子宫静脉血中的VEGF水平明显高于外周静脉血(P=0.019),子宫肌瘤患者外周静脉血中的VEGF水平明显高于对照人群外周静脉血的VEGF水平(P=0.013)。子宫重量、肌瘤总重量、肌瘤数目、最大肌瘤最大径线都与子宫肌瘤患者子宫静脉和外周静脉VEGF呈显著正相关。结论:VEGF可能参与了子宫肌瘤的生长和病情发展。  相似文献   
33.
目的探讨经体外反搏治疗的冠心病患者血清对血管内皮细胞基因表达的调控效应。方法分别取接受体外反搏治疗的冠心病患者1、24和36h时间点的血清,用于培养人脐静脉血管内皮细胞。用cDNA基因芯片检测3个治疗时点反搏前、后血管内皮细胞基因表达谱。结果反搏前后比较,有10个基因(核转录因子、真核转录启动因子-4、平滑肌的肌球蛋白重链、α2-肌动蛋白、微管蛋白β肽链、组织相容蛋白G、黑色素黏附分子、神经介素B受体、蛋白激酶4K2、血小板凝血酶敏感蛋白-1)的表达在3个治疗时点上出现显著改变。在1h点均为上调,在24h、36h时点均为下调。结论体外反搏治疗冠心病患者血清对血管内皮细胞的炎症反应、细胞凋亡相关基因表达有调效应,并随体外反搏治疗时间的增加早抑制其表达的趋势。  相似文献   
34.
Antibodies against nerve growth factor (NGF) in sera were detected by enzyme-linked immunosorbent assays (ELISA), by their isolation after passage of sera through NGF immunoadsorbent columns and by their specificity to bind and immunoprecipitate mouse NGF as well as to stain by immunohistochemical methods cellular sites of NGF synthesis. Increased levels of anti-NGF antibodies were found in sera of herpes simplex virus (HSV)-infected patients but not in HSV-inoculated rabbits. As HSV latency is known to be promoted by NGF in vitro, these results may suggest that anti-NGF antibodies modulate the cytokine function of NGF and thus might play a role in HSV infection. The biological function of circulating antibodies against NGF, in general, is now open to future investigation.  相似文献   
35.
张伟  刘建伟 《中国热带医学》2007,7(10):1799-1800
目的探讨肝硬化患者血清中甲状腺素水平的变化与肝硬化病变程度及其临床实验室检查之间的相关性。方法用放免法测定肝硬化患者血清FT3、FT4、PC-Ⅲ、Ⅳ-C、LN及HA,并按Child—Pugh方法将肝功能分为A、B、C三级。结果随着肝硬化病变程度的加重,血清肝纤维化指标逐渐增高,甲状腺素呈下降趋势,同时血清甲状腺素水平与肝硬化的低蛋白血症、腹水及凝血酶原时间密切相关。结论肝硬化患者体内存在不同程度的甲状腺素水平紊乱,紊乱程度与肝功能受损程度有明显相关性,联合检测血清FT3、FT4、PC-Ⅲ、Ⅳ—C、LN及HA对估计肝硬化病变程度及判断预后有十分重要的临床价值。  相似文献   
36.
目的:通过观察中药知母对醛糖还原酶活性的抑制作用,建立一种适用于筛选中草药醛糖还原酶抑制剂的模型。方法:大鼠12只随机分成3组:空白对照组、知母组、阳性药物组,分别给予生理盐水、知母水提液、依帕司他水溶液灌胃。采用“通法”给药方案制备含药血清,部分血清经过丙酮预处理。将知母水提液和含药(知母)血清分别加人体外建立的以DL-甘油醛为底物、NADPH为辅酶的醛糖还原酶活性测定体系。结果:丙酮处理过的空白血清较未处理的空白血清对酶活性的影响更小;知母水提液对醛糖还原酶抑制率达99%,含药(知母)血清对醛糖还原酶抑制率达67%。结论:运用血清药理学实验方法建立的筛选模型能有效、可靠的进行中草药醛糖还原酶抑制剂的筛选。  相似文献   
37.
目的 探讨血清瘦素在男生青春期发育中的作用。方法 健康男生170名,调查首次遗精时间,测定血清瘦素、睾酮、促卵泡成熟激素、黄体生成激素水平,采用多元Logistic回归模型分析男生青春期发育的影响因素;同时,连续两年观察,分析血清瘦素在青春期的动态变化。结果 末次研究已遗精组血清瘦素、睾酮、促卵泡成熟激素、黄体生成激素水平均明显高于未遗精组。多因素分析显示血清瘦素、睾酮、促卵泡成熟激素、体重为男生青春期发育的独立影响因素。初次资料分析,遗精前组血清瘦素、睾酮明显高于未遗精组。结论 血清瘦素、睾酮、促卵泡成熟激素、体重为男生青春期发育的独立影响因素,男生遗精前期血清瘦素、睾酮已有明显改变。  相似文献   
38.
目的:利用抑制消减杂交(suppression subtractive hybridization,SSH)和cDNA表达谱芯片筛选早期活化的肝星状细胞与大鼠正常肝脏组织、轻度肝纤维化组织、重度肝纤维化组织中差异表达的基因.方法:从SSH构建的大鼠轻度和重度肝纤维化中两个差异cDNA文库中挑选1 000条上调显著的基因,与正常大鼠4 136条基因克隆制作成一张芯片,筛选持续期活化的肝星状细胞相关基因.结果:获得与HSC持续活化相关的上调基因633条,下调基因715条,其中血清和糖皮质激素调节蛋白激酶(SGK)在正常大鼠基因克隆和2、8周SSH上调差异基因中均呈上调信号.结论:联合应用SSH和cDNA表达谱芯片是筛选和鉴定不同样本中差异表达基因的快速、经济和有效方法;SGK可能作为多种细胞信号传导通路和细胞磷酸化级联反应的一个功能性交汇点,参与了肝星状细胞的早期活化和信号传导.  相似文献   
39.
用酶联免疫吸附测定法(ELISA)观察了96例正常人,11例原发性肝细胞肝癌(HCC)、28例乳癌(BC)、31例肺癌(LC)、26例乳腺纤维瘤(BF)、11例肺炎(LF)及11例肺结核(TB)患者的血清同工铁蛋白(Serum isoferritin,SIF)水平。结果显示:正常人与HCC、BC、LC、BF及LF患者之间的SIF水平存在非常显著差异(P<0.01或P<0.001),在上述各类疾病中恶性肿瘤与相应组织的非癌性疾病患者之间的SIF水平也呈现非常显著的差异(BC与BF间、LC与LF间的P<0.01,LC与TB间的P<0.001)。SIF对检测HCC、LC及BC有较高的灵敏度,对鉴别这些恶性肿瘤具有重要价值。  相似文献   
40.
Summary Sera from 17 patients with Type I diabetes and 19 healthy volunteers have been examined to evaluate whether the kinetics of the binding of drugs to Site II of serum albumin is altered in diabetes. Stopped-flow measurements showed that the association velocity and the affinity constants of the fluorescent marker dansylsarcosine were significantly lower in diabetics (160 s–1 and 2.0 × 105 l·mol–1) than in non-diabetics (196s–1 and 4.0 × 105 l·mol–1). The dissociation velocity was not different [20.3 s–1 vs. 19.4 s–1]. Although patients with a reduced albumin concentration were excluded the diabetics had significantly lower concentrations than the healthy volunteers. There was a significant correlation between decreased glycosylation of albumin and increased association velocity. The dissociation velocity constants were correlated with the molar concentration ratio of free fatty acids/human serum albumin. Thus, the extent of glycosylation and the amount of fatty acids bound per mole albumin can both affect the kinetics of drug binding to Site II. The lower affinity in patients with Type I diabetes is due to the increased in the glycoalbumin concentration.  相似文献   
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