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31.
对流行性出血热病毒(EHFV)特异性转移因子(EHFV-TF)的制备、特性及在小鼠体内的活性作用进行了研究。其理化性状与普通 TF 非常相似,能激活淋巴细胞的 E 受体(激活率为65.54%),明显提高 Et-RFC 的形成率。E-HFV-TF 还具有特异性抗原依赖活性:①促进 BALB/C 小鼠和 NIH 裸鼠特异性抗体的产生;②促进 LACA 小鼠脾细胞对 EHFV 反应的特异性应答;③促进脾细胞在 EHVF 存在时对 PHA 诱导下的增殖反应(促时率为151.3%)。EHFV—TF可推迟动物感染 HEFV 后的发病期,延长病程和推迟死亡时间;减轻发病动物脑肺充血、出血、水肿现象和肝肾病理损害程度。结果表明 EHFV-TF 不仅具有提高细胞免疫的非特异活性,而且具有对 EHFV 抗原的依赖活性。本研究提示,E-HFV-TF 可用于 EHFV 感染病人的治疗。 相似文献
32.
目的 检测黑龙江省2019—2021年肾综合征出血热(hemorrhagic fever with renal syndrome, HFRS)疑似患者血清标本中的汉坦病毒急性期和恢复期抗体水平,为该疾病防控提供科学依据。方法 应用酶联免疫吸附法对采集到的肾综合征出血热疑似患者急性期血清样本进行汉坦病毒IgM抗体检测,对恢复期血清标本进行IgM单抗体、IgG单抗体检测,使用SPSS 19.0软件对各年份间患者急性期血样IgM抗体阳性率进行χ2检验分析,使用EpiData 3.1和Excel2003软件对患者性别、职业、年龄、发病日期及初诊间隔时间数据进行整理分析。结果 共检测肾综合征出血热疑似患者急性期血清351份,恢复期血清208份。急性期血清标本IgM抗体阳性317份,阳性率为90.31%,各年份之间患者急性期IgM抗体阳性率差异无统计学意义(χ2=0.895,P=0.639)。患者恢复期血清IgM单抗体阳性32份(15.39%);血清IgG单抗体阳性28份(13.46%);IgM、IgG抗体双阳性148份(71.15%)。男女患者性别比4... 相似文献
33.
34.
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
35.
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
36.
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
37.
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
38.
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
39.
In a study of immunotherapy 41 children with seasonal rhinoconjunctivitis due to deciduous tree pollen allergy were monitored by means of symptom scoring, patient self-evaluation, conjunctival provocation tests and lymphocyte proliferation in vitro to the allergen. The lymphocyte responsiveness to birch pollen decreased significantly during the first year of immunotherapy. However, neither the lymphocyte responsiveness before treatment nor changes in lymphocyte reactivity during the immunotherapy correlated with the clinical efficacy of the therapy as evaluated by changes in symptom scores, self-evaluation or conjunctival provocation test changes in the individual patients. The results indicate the lymphocyte responsiveness to an allergen cannot be used to select patients for immunotherapy, i.e. to predict whether a patient would benefit from immunotherapy or not, or to evaluate the effects of immunotherapy after beginning the treatment. However, lymphocyte proliferation response to an allergen indicates clinical sensitivity. 相似文献
40.
Bruce S. Seal Robert B. Klieforth Anthony E. Castro Werner P. Heuschele 《Methods in Cell Science》1988,11(2):49-55
Summary Cultures of fetal aoudad sheep kidney (FAK), bovine embryonic lung (BEL), and African green monkey kidney (Vero) cells were compared for differential replication of alcelaphine herpesviruses. Cell-free virus appears more rapidly when infected cells are incubated at 33° C rather than at 37° C. Events in the replication and morphologic development of several alcelaphine herpesvirus isolates have been documented using light and electron microscopy. Techniques for indirect immunofluorescence and serum virus neutralization are described. When virus free of host-cell contaminants is desired for biochemical analysis, virus isolates are initially purified on sucrose gradients and then further purified by density gradient centrifugation in Percoll. 相似文献