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991.
用圆二色光谱、荧光光谱及紫外差光谱研究镁钙离子诱导的FⅨ、PC的构象变化并通过蛋白负染电镜及荧光偏振实验观察了各构象与FⅨ、PC特异单抗的连接状况。FⅨ、PC在镁钙离子诱导下,其3种光谱均发生显著变化,并且与缓冲液中的金属离子浓度有关。FⅨ、PC的特异单抗仅与FⅨ、PC的某种特定构象发生连接反应。  相似文献   
992.
血浆脑钠肽水平对冠心病诊断价值的初步探讨   总被引:1,自引:0,他引:1  
目的通过检测观察冠心病患者血浆中脑钠肽(BNP)水平的改变,并与其肌钙蛋白I(cT n I)水平和高敏感性C反应蛋白(hs CRP)水平变化相比较,初步探讨将BNP作为冠心病临床诊断和治疗的标志物的可靠性。方法2004年3~11月,以分层随机抽样法获取西安地区健康人群血浆样本195份(男性132名,女性63名),西京医院住院患者血浆279份(包括129名冠心病、60名糖尿病、62名肺病疾患、28名单纯眼部疾患),利用微粒子酶免分析法和动态定时散射比浊法分别检测上述血浆BNP浓度、cT n I浓度及hs CRP浓度;将以上数据进行统计学分析,比较冠心病组与非冠心病组的差异显著性。结果统计学分析证实:冠心病组与正常组在BNP水平、cT n I水平及hs CRP水平上均存在非常显著性差异(P<0.01),而其中又以BNP水平差异显著性最大(P=0.001);糖尿病组、肺病组以及眼科阴性对照组的BNP浓度结果与正常组比较则显示无统计学意义(P>0.05)。结论血浆BNP浓度在冠心病患者中显著升高,进一步显示了其在心脏疾患中潜在的临床价值。  相似文献   
993.
994.
目的 探讨甲醛对人脐静脉内皮细胞的损伤作用及可能机制。方法 将人脐静脉内皮细胞暴露于不同浓度甲醛(0、5、10、20、40、80μmol/L)下;同时以过氧化氢为阳性对照组,抗氧化药物维生素C为保护组。24h后通过MTT比色法检测细胞生长抑制率,硫代巴比妥酸比色法检测丙二醛含量,观察甲醛是否对内皮细胞具有损伤作用及维生素C对甲醛损伤的内皮细胞是否具有保护作用。结果 甲醛能抑制细胞的生长活性,细胞生长抑制率随甲醛浓度的增加而增加;甲醛诱导细胞外丙二醛的生成,且其含量随甲醛浓度的增加而增加。维生素C能降低甲醛对内皮细胞的生长抑制率,降低细胞外MDA含量。结论 甲醛能诱导内皮细胞产生损伤作用,这种作用与其增加内皮细胞产生过多的脂质过氧化物有关。抗氧化刺维生素C能减轻甲醛对内皮细胞的氧化损伤。  相似文献   
995.
Sepsis continues to be a major clinical problem that is difficult to treat, as the pathophysiology of the disease is still unclear. Despite promising experimental strategies, therapeutic interventions have been largely unsuccessful. There is now increasing evidence that the disturbance of innate immunity during sepsis and multiorgan dysfunction syndrome (MODS) may be linked to uncontrolled activation of the complement system. Especially, the powerful anaphylatoxin C5a seems to play a key role in the development of immune paralysis. In this review, we describe our present understanding of the role of complement in the inflammatory response during sepsis and MODS.  相似文献   
996.
《Renal failure》2013,35(9):915-922
Background and aims: Hepatitis C virus (HCV) is now recognized as one of the major causes of chronic liver disease. It is also one of the most common complications in maintenance hemodialysis (HD) patients. Tumor necrosis factor (TNF)-α promoter polymorphisms are observed to modulate TNF-α levels and thought to have an effect on susceptibility to HCV infection and the virus clearance, but the results are inconsistent. In this study, a systematic review and meta-analysis of the published data was performed to evaluate the relationship between the TNF-α-238, -308 polymorphisms and HCV infection. Methods: A total of 15 studies published were analyzed, which were indexed from PubMed, Embase, and CNKI databases (up to December 2010). All the data were analyzed using RevMan 4.2 software. Odds ratios (OR) and confidence intervals (95% CI) were calculated by fixed or random-effects models. Heterogeneity and publication bias across the studies were also explored. Results: The data showed no significant association between TNF-α-308, -238 gene polymorphisms and the susceptibility to HCV infection in the global group (p = 0.28, p = 0.38, respectively) and the sub-groups (European, American, African, and Asian). Besides, the distributions of TNF-α-308, -238 A/G alleles were also not significantly different between the persistent infection group and the spontaneous clearance group (p = 0.64, p = 0.75, respectively). Conclusion: TNF-α-238, -308 gene polymorphisms might have no effect on susceptibility to HCV infection and the virus clearance. The findings of this meta-analysis have implications in the optimal prevention of HCV in HD patients and in the guidance of future research.  相似文献   
997.
Over 10% of deceased donors in 2011 met PHS/CDC criteria for infectious risk donor (IRD), and discard rates are significantly higher for kidneys from these donors. We hypothesized that patient phenotypes exist for whom the survival benefit outweighs the infectious risk associated with IRDs. A patient‐oriented Markov decision process model was developed and validated, based on SRTR data and meta‐analyses of window period risks among persons with IRD behaviors. The Markov model allows patients to see, for their phenotype, their estimated survival after accepting versus declining an IRD offer, graphed over a 5‐year horizon. Estimated 5‐year survival differences associated with accepting IRDs ranged from ?6.4% to +67.3% for a variety of patient phenotypes. Factors most predictive of the survival difference with IRD transplantation were age, PRA, previous transplant, and the expected time until the next non‐IRD deceased donor offer. This study suggests that survival benefit derived from IRD kidneys varies widely by patient phenotype. Furthermore, within the inherent limitations of model‐based prediction, this study demonstrates that it is possible to identify those predicted to benefit from IRD kidneys, and illustrates how estimated survival curves based on a clinical decision can be presented to better inform patient and provider decision‐making.
  相似文献   
998.
999.
Background. We investigated the possible association between antichlamydial antibodies and pulse wave analysis (PWA) parameters in a cohort of patients with coronary artery disease (CAD). Methods. The augmentation index (AI), the reflection time index (RTI) and the time to the beginning of the reflected wave (CT-1) were estimated (Sphygmocor ATCOR Medical). IgA titers?≥?40 and IgG ≥80 were considered as positive (microimmunofluorescence test). Patients also underwent coronary angiography, ultrasound carotid measurements and 24 h ambulatory blood pressure (BP) measurements. Results. No differences existed in the traditional risk factors for CAD between the seronegative and seropositive IgA/ IgG groups. IgA seropositive subjects had higher values of AI (p?<?0.01) comparing to seronegatives whilst the levels of CT-1 and RTI were lower (p?<?0.011 and p?<?0.02 respectively). No differences in AI, CT-1 and RTI values were found between IgG seropositive/ seronegatives patients. Conclusions. An association was indicated between IgA antichlamydial titers and PWA parameters in patients with CAD, supporting that the connecting link between arterial stiffness and CAD might include this microorganism.  相似文献   
1000.
Diagnostic analysis of clinical markers including serum IgA levels and serum IgA/C3 ratio in patients with IgA nephropathy is described. One hundred patients with IgA nephropathy (IgA nephropathy group) and 100 patients with other primary glomerular diseases (non-IgA nephropathy group) were examined. The analysis was performed to distinguish between these two groups using four clinical markers: 1) more than five red blood cells in urinary sediments, 2) persistent proteinuria (urinary protein of more than 0.3 g/day), 3) serum IgA levels of more than 315 mg/dl, and 4) a serum IgA/C3 ratio of more than 3.01. Patients with three or four clinical markers were easily diagnosed as having IgA nephropathy in this study. Furthermore, there was a significant difference in these clinical markers between the good prognosis and relatively good prognosis groups (Groups I and II) and the relatively poor prognosis and poor prognosis groups (Groups III and IV) of IgA nephropathy patients. It appears that the presence of microscopic hematuria and/or persistent proteinuria, high serum IgA levels, and the serum IgA/C3 ratio are useful for distinguishing IgA nephropathy from other primary renal diseases. It is postulated that these clinical markers are also useful for diagnosis of IgA nephropathy without renal biopsy.  相似文献   
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