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51.
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
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急性脑出血患者血清白介素-6和转化生长因子-β1含量的变化及其临床意义 总被引:4,自引:0,他引:4
目的探讨急性脑出血患者血清白介素-6(IL-6)和转化生长因子β1(TGF-β1)水平在发病过程中的动态变化及其临床意义.方法采用双抗体夹心法检测30名正常人(对照组)和30例急性脑出血患者病后第1、3、7、14 d的血清IL-6和TGF-β1浓度.结果脑出血组在病程第1、3、7 d血清IL-6水平均比对照组明显增高(均P<0.05),TGF-β1水平均明显减低(均P<0.05),至第14 d血清IL-6、TGF-β1水平均接近正常水平.血清IL-6水平在病程第1 d达到峰值(P<0.05),TGF-β1在病程第3 d为低谷值(P<0.05).大量脑出血患者血清IL-6水平均明显高于中、小量出血患者(均P<0.05).不同出血量患者之间TGF-β1水平的差异无显著性(P>0.05).神经功能缺损程度与血清IL-6水平呈正相关(r=0.625,P<0.05),与TGF-β1水平无关(r=0.001,P>0.05).IL-6水平与TGF-β1水平无明显相关性.结论 IL-6、TGF-β1与脑出血的病理过程有密切关系.血清IL-6浓度测定对判断脑出血的病情严重程度有一定意义. 相似文献
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T. Kobayashi F.A. Neethling S. Taniguchi Y. Ye M. Niekrasz E. Koren W.W. Hancock H. Takagi D.K.C. Cooper 《Xenotransplantation》1996,3(3):237-245
Abstract: We examined whether hyperacute rejection (HAR) of a discordant xenograft in a nonhuman primate model could be inhibited by the anticomplement agents, FUT-175 (FUT) and K76COOH (K76). The inhibitory effect of FUT and K76 on baboon sera was studied in vitro by i) complement-mediated hemolysis of sheep erythrocytes (by measuring serum CH50) and ii) cytotoxicity to cultured pig kidney (PK15) cells. The in vivo administration of FUT (at 0.2–25 mg/kg/h i.v. continuously) and K76 (50 mg/kg i.v. bolus) allowed evaluation of the serum levels of these drugs. Both FUT and K76 inhibited serum CH50 in a concentration-dependent manner. An enhanced effect was obtained by combining K76 with FUT therapy. High concentrations of FUT (>10-4 M) and K76 (>103 μxg/ml) were necessary to suppress serum CH50 to <5% of the normal level. However, PK15 cytotoxicity remained at >50% in the presence of i) 10-4 M of FUT, ii) 103 μg/ml of K76, and iii) 10-6 M of FUT + 103 μg/ml of K76. Pig heart transplantation (HTX) was performed in two baboons receiving FUT (1 mg/kg/h i.v. continuously) and K76 (at 200 mg/kg ×1 or 400 mg/kg + 200 mg/kg × 2 i.v, respectively). Cytotoxicity of the serum to PK15 cells at the time of HTX showed 39% and 1% cell death, respectively, in these two baboons, and the CH50 level was 1% (of control level) and 0%, respectively. Graft survival was 4.5 hours and 10 hours (with death of the baboon), respectively (compared with a mean of 29 minutes in control experiments). Both excised grafts showed typical features of hyperacute rejection. Immunopathological studies revealed deposition of C1q, C3d, C6, properdin, and Factor B, demonstrating that complement activation was not fully inhibited by FUT and K76. We conclude that i) FUT and K76 are indeed potent complement inhibitors, ii) the dosages of FUT and K76 necessary to suppress complement-mediated injury cannot be extrapolated from previously reported data obtained from serum CH50 levels, and iii) higher (possibly toxic) dosages will be required to inhibit complement activation completely. It seems unlikely that HAR will be prevented by these drugs alone, although they may be beneficial when combined with other forms of therapy. 相似文献
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Oxidative capacity interacts with oxygen delivery to determine maximal O2 uptake in rat skeletal muscles in situ 总被引:2,自引:1,他引:2
When intracellular recordings were made from the antral region of murine stomach, cells with three different patterns of electrical activity were detected. One group of cells generated follower potentials, the second group generated pacemaker potentials and the third group generated slow waves that consisted of primary and secondary components. Slow waves recorded in different regions of the gastric antrum had similar amplitudes but different characteristic shapes. At the greater curvature, slow waves had large initial components. Midway between the greater and lesser curvature, the amplitude of the initial component was reduced and at the lesser curvature an initial component was difficult to detect. When the distributions of myenteric (ICC-MY) and intramuscular interstitial cells of Cajal (ICC-IM) were determined, using an antibody to Kit, ICC-MY were found to be present at the greater curvature but were greatly reduced in density at the lesser curvature. In contrast, ICC-IM were found in the circular layer of each region. When recordings were made from the antrum of W/WV mice, which lack ICC-IM, incomplete slow waves were detected and their amplitudes fell from the greater to the lesser curvature. Again, a corresponding fall in the density of ICC-MY was detected. The observations indicate that the contribution of ICC-MY and ICC-IM to the generation of slow waves varies in different regions of the mouse gastric antrum. 相似文献
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分析47例骨髓穿刺干抽的临床和病理改变,干抽占同期1319例骨穿的3.6%。根据骨髓细胞的密度和间质纤维增殖的程度,把干抽的原因分为4类:高细胞伴间质细胞增多者19例(42.2%);间质细胞增多者14例(31.1%);高细胞者8例(17.8%)及低细胞者4例(8.9%)。主要疾病为:急性淋巴细胞白血病(25.5%),急性非淋巴细胞白血病(17.0%),慢性白血病(14.9%),骨髓转移瘤(10.6 相似文献