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21.
作者合成了13个对-苯二甲酸衍生物,其中有9个化合物尚未见文献报道。通过对HL-60细胞诱导分化活性试验,发现有两个化合物在浓度为5×10 ̄(-6)mol/L时,可使细胞分化率达55%,低于维A酸的分化率(79%,10 ̄(-7)mol/L)。 相似文献
22.
Kent Burnett Gail Ironson Charles Benight Christina Wynings Debra Greenwood Charles S. Carver Dean Cruess Andrew Baum Neil Schneiderman 《Journal of traumatic stress》1997,10(4):673-681
The purpose of this study was to develop and evaluate a measure of perceived disruption during rebuilding following a disaster. Two eight-item scales, which measured intensity of disruption during the entire repair phase (Intensity-RP) and intensity of disruption during the past month (Intensity-PM) were developed and administered to 135 survivors of Hurricane Andrew. At 9 to 12 months postdisaster, Intensity-RP and Intensity-PM were both significantly associated with scores on the Global Severity Index of the SCL-90-R, and with scores on the Impact of Event-Intrusion Scale; Intensity-PM alone was significantly associated with PTSD scores. Regression analyses indicated that each scale contributed significant unique variance in predicting mental health symptoms, even after controlling for relevant demographic and initial disaster exposure variables. 相似文献
23.
本实验将赖型钩端螺旋体(简称钩体)DNA基因库的克隆pCX7制备成 ̄(32)P-重组DNA探针,对8个不同血清群的17株问号状钩体、双曲钩体PatocⅠ株以及细螺旋体3055株DNA进行打点杂交;同时用15种DNA片断进行限制性内切酶谱分析。结果表明,该重组DNA具有问号状钩体种(Species)特异性,但与不同问号状钩体之间的同源性程度有差别;限制性内切酶谱分析发现pCX7重组DNA片段长约1.7kb,具有1个Bg1Ⅱ识别位点和3个BstB1识别位点。 相似文献
24.
作者以1%乙酸冲洗SD大鼠子宫内膜,获得子宫内膜酸溶性提取物。利用琼脂糖弥散法和电泳凝胶琼脂糖弥散法抗菌试验发现,子宫内膜提取物有三条主蛋白带对致病性大肠杆菌ML-35P耐药株有强抗菌活性,这三条抗菌蛋白带命名为RatUP-1,RatUP-2和RatUP-3,分别占子宫内膜提取物总蛋白量的4.5%,5.7%和6.6%。虽然提取物存在溶菌的活性,但其含量甚微,在AU一PAGE图谱上亦未能显现溶菌酶条带。本实验的结果提示子宫内膜合成一类抗菌多肽,可能在子宫抗菌机制中发挥重要作用。 相似文献
25.
1986年10月至1990年3月,先后在贵州省EHF野鼠型疫区遵义、安顺两县和家鼠型疫区凯里市选点,监测丘陵地区自然状态下影响EHF流行的主要因素,连续两年的逐月监测结果表明,人间流行的强度、临床表现和流行特征的不同与主要宿主动物种类、密度和带病毒率以及病原体的毒力和型别有关。 相似文献
26.
Lorenzo Moretta Maria Cristina Mingari Daniela Pende Cristina Bottino Roberto Biassoni Alessandro Moretta 《Journal of clinical immunology》1996,16(5):243-253
Natural Killer cells are likely to play an important role in the host defenses because they kill virally infected or tumor cells but spare normal self-cells. The molecular mechanism that explains why NK cells do not kill indiscriminately has recently been elucidated. It is due to several specialized receptors that recognize major histocompatibility complex (MHC) class I molecules expressed on normal cells. The lack of expression of one or more HLA class I alleles leads to NK-mediated target cell lysis. Different types of receptors specific for groups of HLA-C, HLA-B, and, very recently, HLA-A alleles have been identified. While in most instances, they function as inhibitory receptors, an activatory form of the HLA-C-specific receptors has been identified in some donors. Molecular cloning of HLA-C-, HLA-B- or HLA-A-specific receptors has revealed new members of the immunoglobulin superfamily with two or three Ig-like domains, respectively, in their extracellular portion. While the inhibitory form is characterized by a long cytoplasmic tail associated with a non-polar transmembrane portion, the activatory one has a short tail asociated with a Lys-containing transmembrane portion. Thus, these human NK receptors are different from the murine Ly49, that is a type II transmembrane protein characterized by a C-type lectin domain. A subset of activated T lymphocytes expresses NK-type class I-specific receptors. These receptors exert an inhibiting activity on T cell receptor-mediated functions and may provide an important mechanism of downregulation of T cell responses. 相似文献
27.
Douglas M. Strong John R. Ortaldo Franco Pandolfi Annette Maluish Ronald B. Herberman 《Journal of clinical immunology》1982,2(3):214-221
Cryopreserved human peripheral blood mononuclear cells (PBMC) were tested for natural killer (NK) and antibody-dependent cellular cytotoxicity (ADCC) and for high-affinity (29°C) and total (4°C) rosette formation with sheep erythrocytes. PBMC produced variable NK activity following freezing and thawing, but consistently reacted well in ADCC. A significant correlation was found between low NK activity and a decreased percentage of low-affinity rosette-forming cells. On the contrary, the number of large granular lymphocytes (LGL), among which NK cells are restricted, and the reactivity with the monoclonal antibody OKT10, which recognizes the majority of LGL in the peripheral blood, were not significantly altered by cryopreservation. Cryopreserved cells proved to be excellent controls for determining the day-to-day variability of the NK assay and for selecting optimum conditions for this test in the clinical immunology laboratory. 相似文献
28.
Jean E. Merrill 《Journal of clinical immunology》1983,3(1):42-50
Though purported to be identical cells (or in identical populations of cells), the natural killer (NK) cell mediating spontaneous natural cytotoxicity and the killer (K) cell mediating antibody-dependent cellular cytotoxicity (ADCC) may not be totally identical, at least in susceptibility to regulation by the immunomodulators prostaglandin E1 (PGE1) and interferon (IFN). We demonstrate here that NK cells are always enhanced by IFN, while K cells are inhibited from binding targets, resulting in fewer effectors at optimal concentrations of antibody. Only at 10- to 100-fold suboptimal concentrations of antibody is ADCC activity enhanced. As measured by magnitude of inhibition and dose-response titration, ADCC activity is less sensitive to the effects of PGE1 than is NK activity in the51Cr release assay and single-cell assay. After overnight incubation with or without PGE1, whatever sensitivity ADCC activity had to PGE1 is lost. However, NK cells incubated in the presence of PGE1 overnight are still sensitive to inhibition. Indomethacin boosts NK activity without having any effect on ADCC activity. Finally, NK activity is substantially reduced by overnight incubation of cells at room temperature, which has no effect on K cells. 相似文献
29.
James W. Verbsky Mary K. Hintermeyer Pippa M. Simpson Mingen Feng Jody Barbeau Nagarjun Rao Carlyne D. Cool Luis A. Sosa-Lozano Dhiraj Baruah Erin Hammelev Alyssa Busalacchi Amy Rymaszewski Jeff Woodliff Shaoying Chen Mary Bausch-Jurken John M. Routes 《The Journal of allergy and clinical immunology》2021,147(2):704-712.e17
30.
Lena Möbus Elke Rodriguez Inken Harder Agatha Schwarz Ulrike Wehkamp Dora Stölzl Nicole Boraczynski Sascha Gerdes Thomas Litman Andreas Kleinheinz Susanne Abraham Annice Heratizadeh Christiane Handrick Eva Haufe Jochen Schmitt Thomas Werfel Stephan Weidinger 《The Journal of allergy and clinical immunology》2021,147(5):1959-1965.e2