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91.
目的 探讨急性脑梗死患者血清补体C1q/肿瘤坏死因子相关蛋白3(CTRP-3)、D-二聚体、可溶性髓样细胞触发受体2(sTREM2)水平及相关临床特征与溶栓后出血性转化(HT)的关系。方法 回顾性分析2018年9月—2022年9月在青海省人民医院接受溶栓治疗的120例急性脑梗死患者的临床资料,根据患者溶栓后是否发生HT分为HT组(30例)、非HT组(90例)。比较两组患者的临床资料及血清CTRP-3、D-二聚体、sTREM2水平。采用多因素逐步Logistic回归分析急性脑梗死患者溶栓后发生HT的危险因素;绘制受试者工作特征(ROC)曲线,分析急性脑梗死患者溶栓后HT预测模型预测HT发生的价值。结果 HT组心房颤动(以下简称房颤)、大面积脑梗死、入院NIHSS评分≥ 15分占比高于非HT组(P <0.05),血清CTRP-3水平低于非HT组(P <0.05),D-二聚体、sTREM2水平高于非HT组(P <0.05)。血清CTRP-3、D-二聚体、sTREM2水平预测急性脑梗死患者溶栓后发生HT的敏感性分别为66.7%(95% CI:0.598,0.756)、70.0%(95% CI:0.607,0.812)、80.0%(95% CI:0.714,0.889),特异性分别为73.3%(95% CI:0.636,0.821)、86.7%(95% CI:0.778,0.923)、86.7%(95% CI:0.747,0.942)。多因素Logistic逐步回归分析结果显示,房颤[O^R=1.237(95% CI:1.103,1.387)]、大面积脑梗死[O^R=2.338(95% CI:1.292,4.231)]、入院NIHSS评分≥ 15分[O^R=2.087(95% CI:1.231,3.538)]、CTRP-3 ≤ 269.265 μg/L [O^R=3.006(95% CI:1.508,5.992)]、D-二聚体≥ 2.625 mg/L [O^R=2.649(95% CI:1.374,5.107)]、sTREM2 ≥ 314.675 ng/L [O^R=2.328(95% CI:1.411,3.841)]是急性脑梗死患者溶栓后发生HT的危险因素(P <0.05)。根据多因素Logistic逐步回归分析结果建立急性脑梗死患者溶栓后HT预测模型,Logit(P) = -33.887 + 0.213×房颤+ 0.849×大面积脑梗死+0.736×入院NIHSS评分+ 1.101×CTRP-3 + 0.974×D-二聚体+ 0.845×sTREM2;ROC曲线分析结果表明,预测模型预测HT发生的敏感性为93.3%(95% CI:0.841,0.991),特异性为87.8%(95% CI:0.808,0.976)。结论 血清CTRP-3、D-二聚体、sTREM2水平与急性脑梗死患者溶栓后HT有关,预测价值较高,且急性脑梗死患者溶栓后HT预测模型预测HT优于各项指标单独预测。 相似文献
92.
93.
94.
Yellow fever (YF) is a zoonotic infection with more than 200,000 cases reported annually. Relatively little is known about YF pathogenesis in humans. In this study, we demonstrate that human vascular endothelial cells are susceptible to infection with wild-type and vaccine strains of the YFV and that these infections lead to a differential cellular response to infection. The infection of endothelial cells with either virus resulted in a significant induction of interferon-inducible genes p 78 and Cig 5 while wild-type virus induced a much more pronounced IL 6 and Bc l2 response than did the vaccine strain. Both viruses induced RANTES gene expression, but only the wild-type virus had corresponding increases in RANTES protein expression. The results demonstrate that the wild-type and vaccine strains of YFV elicit significantly different responses to infection in endothelial cells, despite being nearly identical genetically. These differences may account for the attenuated phenotype of the YFV vaccine strain, though the mechanism remains unclear. These data also point to a role for vascular endothelial cells in YF hemorrhagic fever and also suggest that IL 6 may play a role in increased viral pathogenesis, perhaps by influencing coagulation via release of coagulation co-factors such as fibrin or fibrinogen. 相似文献
95.
O. M. Efremov N. A. Kalinina A. V. Sorokin 《Bulletin of experimental biology and medicine》1979,88(2):859-861
The effect of sodium salicylate, acetylsalicyclic acid, aminopyrine, and phenazone on the ability of granulocytes to produce endogenous pyrogen was studied. Experiments in vitro with verification of the viability of the leukocytes showed that of these antipyretics only sodium salicylate inhibited pyrogen formation.Department of General Pathology, Scientific-Research Institute of Experimental Medicine, Academy of MedicalSciences of the USSR, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR P. N. Veselkin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 8, pp. 166–168, August, 1979. 相似文献
96.
新疆出血热病毒核蛋白基因的高效表达及其在诊断中的初步应用 总被引:2,自引:0,他引:2
目的 克隆并测定了克里米亚 刚果出血热病毒 (CCHFV)中国分离株 (新疆出血热病毒 ,XHFV)BA8816 6株核蛋白 (NP)基因的序列并实现其在细菌中的高效表达与临床诊断的应用。方法 病毒RNA经RT PCR扩增出完整的NP基因。将扩增产物进行序列分析并克隆至融合表达载体pET32a ,使重组质粒在大肠杆菌BL 2 1中高效表达。将融合蛋白经初步纯化后包被ELISA板用于抗体检测。结果 XHFVBA8816 6株NP基因序列以及推导的氨基酸序列与其它XHFV的NP基因和蛋白序列同源性较高 ,在进化树上形成独立的分支。BA8816 6株NP基因编码 4 82个氨基酸的核蛋白 ,推测的相对分子质量 (Mr)约为 5 4× 10 3。在细菌中表达的融合蛋白经印迹试验证明具有良好的抗原性。以所建立的ELISA方法检测疫区人和动物血清的结果与IFA一致 ,并与临床诊断有很好的符合率。结论 BA8816 6株与其它XHFVBA6 6 0 19、BA84 0 2的NP基因在进化上关系密切 ,综合M基因的序列分析结果 ,人源分离株BA8816 6可能是来自蜱的BA84 0 2变异株。表达于细菌中的核蛋白可作为安全的诊断性抗原用于临床检测及流行病学调查 ,所建立的方法准确、特异、简便、快速 相似文献
97.
N. P. Boye O. P. Salo N. Hyldebrandt J. A. Wihl A. Bevan R. I. Harris J. R. Lovely 《Allergy》1990,45(4):241-248
The safety and efficacy of two birch pollen extracts, one chemically conjugated to alginate (Anjuvac) the other adsorbed to aluminium hydroxide (Alutard), were investigated in an open multicentre comparative study of 63 birch pollen allergic patients. Both extracts decreased the nasal symptoms during the birch pollen season. The changes in specific IgE and IgG were much the same in both treatment groups. The adverse reactions recorded were mild in both groups, but more frequent in the Anjuvac group, probably because of a more aggressive dose schedule though there were twice as many asthmatics in the Anjuvac group. The two investigated allergen extracts were useful alternatives for immunotherapy. 相似文献
98.
The nonstructural protein 3 (NS3) of Dengue virus (DV) is a multifunctional enzyme carrying activities involved in viral RNA replication and capping: helicase, nucleoside 5'-triphosphatase (NTPase), and RNA 5'-triphosphatase (RTPase). Here, a 54-kDa C-terminal domain of NS3 (DeltaNS3) bearing all three activities was expressed as a recombinant protein. Structure-based sequence analysis in comparison with Hepatitis C virus (HCV) helicase indicates the presence of a HCV-helicase-like catalytic core domain in the N-terminal part of DeltaNS3, whereas the C-terminal part seems to be different. In this report, we show that the RTPase activity of DeltaNS3 is Mg2+-dependent as are both helicase and NTPase activities. Mutational analysis shows that the RTPase activity requires an intact NTPase/helicase Walker B motif in the helicase core, consistent with the fact that such motifs are involved in the coordination of Mg2+. The R513A substitution in the C-terminal domain of DeltaNS3 abrogates helicase activity and strongly diminishes RTPase activity, indicating that both activities are functionally coupled. DV RTPase seems to belong to a new class of Mg2+-dependent RTPases, which use the active center of the helicase/NTPase catalytic core in conjunction with elements in the C-terminal domain. 相似文献
99.
BACKGROUND: The clinical efficacy and safety of a six-grass pollen allergoid has been studied. The advent of more exacting clinical guidelines and a better appreciation of the possible mechanisms of treatment prompted this reappraisal. METHODS: A 2-year double-blind multicentre placebo-controlled phase 3 clinical trial was undertaken in 154 patients suffering symptoms of rhinoconjunctivitis with or without asthma (GINA I or II). Therapy comprised two consecutive preseasonal short-courses of subcutaneous injections using a grass pollen allergoid adsorbed to aluminium hydroxide. RESULTS: A combined symptom and medication score (SMS) was used as the primary end-point for clinical efficacy. SMS from the first year showed a significant difference of 26.6% between the two study groups (P=0.026) and this was improved after the second year when there was a 48.4% difference in SMS between active and placebo treatment in favour of the allergoid (P = 0.018). Highly significant increases in grass pollen allergen-specific IgG1 and IgG4 antibody concentrations were measured in association with active treatment. Allergen tolerance was increased as judged by a conjunctival provocation test and significant improvements in quality of life were documented using a standardized questionnaire. The allergoid was well tolerated. CONCLUSIONS: The grass pollen allergoid was shown to be safe and clinically efficacious in the management of hay fever with or without asthma (GINA I or II). 相似文献
100.
目的研究凋亡相关蛋白mdm2、bcl-2和AR(雄激素受体)之间的关系,为脑膜瘤的性激素对抗治疗提供一些新信息。方法从华西医院病理科获得04年1月-07年12月病理诊断明确的脑膜瘤共394例,计算机随机抽样60例,其中良性脑膜瘤(WH0I)41例,用LsAB法做免疫组化染色,检测mdm2、bcl-2、AR的表达。结果在良性脑膜瘤中mdm2、bcl-2、AR的表达率分别为67%、62%、33%,三者之间没有相关关系。结论(1)是否能够作为抗性激素治疗疗效的筛选和/或预测指标,bcl-2比mdm2更有潜在价值。(2)AR在脑膜瘤中的促进生长作用的相对独立性,提示AR可以作为脑膜瘤对抗激素治疗的新靶点进一步研究。 相似文献