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21.
胆红素对新生豚鼠蜗核损伤的动态研究   总被引:2,自引:0,他引:2  
目的 探讨听性脑干反应 (ABR)在胆红素所致听力损伤中的监测价值。方法  2 0只新生 5日豚鼠随机分为胆红素组和对照组 ,胆红素组腹腔注射胆红素 (2 0 0 μg/ g) ,对照组腹腔注射相应体积的生理盐水 (0 1ml/g) ,于腹腔注射前和后 4h、 8h分别记录ABR并观察神经行为状况 ,每组各取 5只于腹腔注射后 4h、 8h分别行蜗核形态学观察。结果 注射胆红素后 ,ABR波潜伏期、波间期呈逐渐延长趋势 ,振幅呈逐渐下降趋势 ,其中波Ⅱ改变出现最早且最明显。用药后 4h ,无明显神经系统症状和形态学改变时 ,Ⅰ -Ⅱ波间期延长及波Ⅱ振幅下降与对照组及用药前比较差异有显著性 (P <0 0 1) ;用药后 8hABR改变更明显 ,同时伴有神经症状和镜下形态学改变 ,蜗核体积及大椭圆细胞截面积显著性减小 (P <0 0 1)。结论 ABR是监测胆红素所致听力损害早期的敏感指标 ,优于耳蜗电图和耳声发射等主要反映周围听觉系统功能状态的电生理技术 ,加强高胆红素血症新生儿的ABR动态监测有非常重要的临床意义  相似文献   
22.
从胆汁中提取胆红素,所得成品,其含量和收率受许多因素的影响。本文通过正交表实验选择,结果表明,最主要因素为醇析酸化pH值,其次为乙醇浓度、乙醇用量和抗氧剂用量等。  相似文献   
23.
Combined direct injection venography (DIV) and equilibrium angiography (EA) were performed in 13 patients, by injecting in vitro labeled 99mTc autologous RBC, via pedal veins, and imaging the first pass and the equilibrium phase. This paired comparative study of DIV with EA shows that DIV has advantages over EA because it provides selective information on the deep venous system from the calves to the inferior vena cava. DIV provides information on the flow dynamics and the high contrast first pass images provide better definition of non filling venous segments as well as visualization of collaterals. When using 99mTc-MAA, lung perfusion can also be imaged. DIV is recommended as the procedure of choice for the diagnosis of DVT and EA should be employed only when pedal vein injection is not possible.  相似文献   
24.
[目的]比较2,4-二氯苯胺重氮法(DCA)和钒酸盐氧化法检测血清结合胆红素的结果。[方法]根据NCCLS(EP6-P)评价方案,评估两种方法的相关性和偏倚。[结果]两种方法的检测结果相关性良好(r=0.9985),Ⅰ、Ⅱ、Ⅲ组检测结果无差异,Ⅳ组结果有差异。[结论]应建立与方法学相对应的血清结合胆红素参考值范围。  相似文献   
25.
目的:探讨生物标志物联合检测对脓毒症相关急性肝损伤患者的早期诊断和预后评估的价值。方法:收集内蒙古科技大学包头医学院第一附属医院重症医学科(ICU)2019年11月-2022年1月收治的104例脓毒症患者临床资料,按照入ICU时是否发生急性肝损伤分为脓毒症相关急性肝损伤组(n=42)和非肝损伤组(n=62),将脓毒症相关急性肝损伤患者按28 d是否存活分为存活组(n=16)和死亡组(n=26),记录104例患者入ICU 6 h内血清正五聚蛋白3(PTX-3)、C-反应蛋白(CRP)、降钙素原(PCT)、总胆红素(TBIL)、谷草转氨酶(AST)、谷丙转氨酶(ALT)、凝血酶原时间国际标准化比值(INR值)、凝血酶原时间(PT)、凝血酶原活动度(PTA)、血小板(PLT)、入ICU 24 h内急性生理与慢性健康状况评估量表II(APACHEII)评分最差值及序贯器官衰竭评估(SOFA)评分;同时记录脓毒症相关急性肝损伤患者28 d预后。PTX-3的相关性采用Spearman相关分析;绘制受试者工作特征曲线(ROC曲线),计算ROC曲线下面积(AUC),分析各指标单独检测以及联合检测对脓毒...  相似文献   
26.
目的 探讨脂联素(APN)、直接胆红素(DB)、甘油三酯(TG)及三者联合对 2 型糖尿病(T2DM)患者大血管病变的诊断价值。方法 选取120例T2DM患者,根据是否合并大血管病变将其分为T2DM组(62 例)和 T2DM+大血管病变组(58 例)。比较两组的临床资料;采用非条件多因素逐步Logistic回归分析T2DM患者合并大血管病变的风险因素;绘制受试者工作特征(ROC)曲线评估APN、DB、TG及三者联合对T2DM患者合并大血管病变的诊断效能。结果 非条件多因素逐步Logistic回归分析结果显示,■是T2DM患者合并大血管病变的危险因素(P <0.05);■是T2DM患者合并大血管病变的保护因素(P <0.05)。ROC曲线分析结果显示,当APN ≤ 5.870 nmol/mL时,诊断T2DM患者合并大血管病变的曲线下面积(AUC)为0.718,敏感性为70.7%(95% CI:0.571,0.815),特异性为61.3%(95% CI:0.480,0.713);当DB ≤ 14.205 mol/L 时,AUC 为 0.772,敏感性为 74.1% (95% C...  相似文献   
27.
In the present study we prepared macroporous polyvinyl alcohol beads. A series of bilirubin adsorbents were generated by immobilization of eight amine agents to the beads as ligands. The adsorption of bilirubin was evaluated by in vitro static and dynamic adsorption tests. The results show that these adsorbents have excellent adsorption efficiency and capacity. Among the eight ligands, trimethylamine (TMA), triethylamine (TEA) and 1,6- hexanediamine(HDA) showed the highest adsorption capacity. The adsorption equilibrium can be achieved in half an hour, and the adsorption percentage of bilirubin was up to 80%. Static electricity and hydrophobic interaction played the main role in bilirubin adsorption, and the adsorption was found to match the monolayer model. The excellent adsorption of these adsorbents indicates their potential in clinical treatment.  相似文献   
28.
Dendritic cells (DCs) are potent antigen presenting cells and possess a direct anti-tumor cytotoxic ability. Nevertheless, the mechanism of anti-tumor cytotoxicity by DCs and the methods for its evaluation are not fully elucidated. In order to clarify this mechanism of cytotoxicity, we examined the ability of DCs 1) to suppress [3H] thymidine (3H-TdR) uptake by tumor cells; 2) to induce cytolysis on 51Cr-labeled tumor cells; 3) and to induce DNA fragmentation on 3H-TdR labeled tumor cells (JAM test). Cytolysis and DNA fragmentation are markers of necrotic and apoptotic mechanisms of cytotoxicity in vitro, respectively. DCs inhibited approximately 38.6% to 54.8% of the growth of B4D6, NB4, U937, and Daudi cells as evaluated by the uptake of 3H-TdR. However no cytolysis was verified by 51Cr-release assay. On the other hand, cytotoxicity rates found using the JAM test ranged from 3 to 81% depending on the cell line and the effector to target cell ratio. The discrepancy of cytotoxicity between 51Cr-release assay and the JAM test may be due to the phagocytosis of apoptotic tumor cells or the absorption of released 51Cr by DCs surrounding the target cells. In conclusion, the JAM test was more sensitive than the 4-h and the 10-h 51Cr-release assay to investigate cytotoxicity mediated by DCs toward hematopoietic tumor cell lines in vitro.  相似文献   
29.
Increased concentration of lipid peroxidation products in patients with primary biliary cirrhosis is related to elevation of serum lipid content, but not to activation of lipid peroxidation. Hyperbilirubinemia in patients with primary biliary cirrhosis is accompanied by a decrease in the concentration of lipid peroxidation products and increase in antioxidant activity of blood serum. Antioxidants play a major role in the prevention of atherosclerosis. We hypothesized that the absence of increased risk of atherosclerosis in patients with primary biliary cirrhosis is due to inhibition of lipid peroxidation in blood serum by antioxidant compound bilirubin. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 1, pp. 23–28, January, 2008  相似文献   
30.
A Direct Comparison of the Skin Conductance and Skin Resistance Methods   总被引:1,自引:0,他引:1  
The purpose of the present study was a direct comparison between simultaneous recordings of skin conductance and skin resistance. Sixty male students received a series of 30 white noise stimuli, while measures were taken continuously from four sites on the palmar surfaces of the fingers. Evaluations were made for response amplitudes, recovery, and for an approximate area measure. Magnitude of reactions and reliabilities were compared using ANOVA procedures. Behavioral concordances were estimated as correlations with the subjects' ratings of stimulus intensities. Conductance and resistance measures do not differ in amplitude, in area, or in strength of their reliabilities and behavioral concordances. No differences in any respect are found between sites. Skin conductance yields significantly (p < .01) shorter recovery times than skin resistance, which is discussed in terms of membrane permeability change.  相似文献   
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