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681.
Hiroya Asou Mariko Eguchi Kazumi Suzukawa Kazuhiro Morishita Kimio Tanaka Munehiro Date Kazuko Hamamoto Nanao Kamada 《British journal of haematology》1996,93(1):68-74
A novel human leukaemia cell line (Kasumi-4) was established from the peripheral blood of a 6-year-old girl suffering from chronic myelogenous leukaemia (CML) in blast crisis. The Kasumi-4 cells had the following characteristic features: undifferentiated blasts which were positive for CD34, CD33 and CD13 surface markers, but negative for myeloperoxidase platelet peroxidase, CD36, CD41 and CD42; chromosome abnormalities of t(9;22;11) (q34;q11;q13), inv(3)(q21q26); and elevated expression of EVI1 gene which is located at chromosome band 3q26. Megakaryocytic maturation was not observed in the liquid culture following the addition of TPA, IL-3, IL-6 or GM-CSF. b2-a2 type of BCR-ABL chimaeric messenger RNA was detected by RT-PCR analysis. This is the first leukaemia cell line with a three-way translocation containing the Ph chromosome and the second cell line with an inv(3)(q21q26). This cell line appears to be useful for studying the mechanisms of leukaemogenesis involving these chromosomal abnormalities and related oncogenes. 相似文献
682.
683.
目的探讨高压氧、山莨菪碱和地塞米松对高原冲击伤的治疗作用。方法 SD大鼠清醒状态下置于高原冲击伤实验平台内,减压至海拔3500m维持6h,然后用BST-Ⅰ型生物激波管致伤,冲击波超压峰值为(343.5±4.176)kPa,伤后按下述分组处理:A组为对照组,不给予任何处理,B、C、D为处理组,分别于伤后0.5h和3h给予高压氧(2个标准大气压)、山莨菪碱(1mg/kg)和地塞米松(1mg/kg)、高压氧与山莨菪碱和地塞米松联合应用处理。观察大鼠伤后6h的死亡率、动脉血气变化和肺形态学改变。结果 A、B、C、D组的死亡率分别为40.7%、17.4%、24.0%和14.3%,D组与A组比较差异显著(P<0.05);PaO2分别平均为(65.250±11.311)、(82.286±5.908)、(72.625±11.783)和(85.125±7.322)mmHg,B组、D组与A组比较P<0.01;SaO2分别平均为(90.5±4.840)%、(95.429±1.339)%、(93.625±2.925)%和(95.750±0.661)%,B组、D组与A组比较P<0.01,C组与A组比较P<0.05;肺出血和肺水肿程度,B组、D组与A组比较有所减轻,C组与A组比较有所加重。结论高压氧、山莨菪碱和地塞米松及高压氧与山莨菪碱和地塞米松联合应用对高原冲击伤大鼠的治疗有效,其中以高压氧与山莨菪碱和地塞米松联合应用效果更好。 相似文献
684.
本研究旨在观察4型含Bromo结构域蛋白(bromodomain-containing protein 4,BRD4)抑制剂GSK525762A对KU812细胞增殖及凋亡的影响及其机制.用GSK525762A 100、250、500、1000、2500和5000 nmol/L处理KU812细胞48和72 h,CCK-8法检测其对细胞增殖的影响;GSK525762A 1.0、2.5和5.0 μmol/L处理72 h,利用流式细胞术检测其对KU812细胞的凋亡诱导作用.将KU812细胞经DMSO和2.5 μmol/L的GSK525762A处理后,利用实时荧光定量PCR观察c-Myc、BCL-2、CDK6、BCL-xL、BAK和BAX基因的mRNA表达水平.结果表明,GSK525762A能显著抑制KU812细胞的增殖,且抑制作用存在量-效关系(r =0.970)和时-效关系(r=0.956);GSK525762A能促进KU812细胞的凋亡;GSK525762A处理后促增殖基因c-Myc、CDK6和抗凋亡基因BCL-2和BCL-xL的mRNA较对照组降低,而促凋亡基因BAK和BAX的转录水平较对照组升高.结论:GSK525762A显著抑制KU812细胞的增殖并促进其凋亡,其机制可能与下调c-Myc、BCL-2、CDK6、BCL-xL的表达和上调BAK、BAX的表达有关. 相似文献
685.
Yang Chang Dong-hai Zhang Quan Hu Ling-ying Liu Yong-hui Yu Jia-ke Chai 《Burns : journal of the International Society for Burn Injuries》2018,44(4):905-916
Background
Burn–blast combined injury is a kind of injury caused by heat and blast at the same time. The lung injury after burn–blast combined injuries is of primary importance, and investigation of lung injury is needed in the clinical care of patients. Computed tomography (CT) is one of the standard tools used to observe the anatomical basis and pathophysiology of acute lung injury.Methods
We applied a method of fast 3D (three-dimensional) reconstruction to calculate the density value of the lung injury by CT analysis. Blast-injury group (BL group), burn-injury group (B group), burn–blast combined injury group (BBL group), and sham control group (C group) were established. Each group had 16 rats. The three-dimensional images of the lung tissue were obtained at 6 h, 24 h, and 48 h according to the CT value. The average density of the whole lung, left lung, and right lung were measured. The lung tissues were paraffin-embedded and HE stained. Smith scoring was performed according to the pathological findings.Results
In the BBL group, the density of the lung tissue was higher than those of the BL group and B group (P < 0.01). The lung tissue density values at 24 h after injury were higher than those at 6 h and 48 h after injury (P < 0.01). Pathological results confirmed the changes of density analysis of the lung tissue.Conclusion
The results have indicated that density analysis through a CT scan can be used as a way to evaluate lung injury in a burn–blast injury. 相似文献686.
This paper aims to experimentally investigate the effects of high volume cement replacement of blast furnace slag (BFS) on the bond, strength and durability of recycled aggregate concrete (RAC). Concrete mixtures were prepared containing 0%, 15%, 30%, 45%, 60% and 75% BFS with each of recycled aggregate and natural aggregate. Measurements of the compressive and bond strength, the resistance to chloride-ion penetration and the water permeability of concrete are reported. In addition, a microhardness test was also performed to evaluate the quality of interfacial transition zone (ITZ) in concrete. Test results of the bond strength and the compressive strength of RAC mixtures, in spite of the cement replacement amount with BFS, show that the concretes result in reduced strength when compared to natural aggregate concrete (NAC) mixtures, while the strength gains for the BFS-based concrete are higher than that of the reference mixtures without BFS at long-term ages. Incorporating BFS in concrete can inherently improve the durability properties by increasing higher resistance to chloride-ion penetration and lower water permeability. This improvement in the mechanical and durability properties of the BFS-based RAC mixture may be due to the additional pozzolanic reaction of BFS, which enhances the properties of ITZ in concrete, resulting in an improvement of the strength of concrete. 相似文献
687.
目的 探讨瓦斯爆炸伤致肺部爆震伤的临床流行病学特点.方法 回顾1990年1月至2010年12月平顶山煤业集团医院132名瓦斯爆炸致肺部爆震伤患者的临床资料,对就诊情况、肺部损伤情况、合并伤、治疗情况及死亡情况等进行分析.结果 56例患者入院时意识清楚,其中30例1~5 d出现咳嗽、咯血等肺部症状,7例出现血胸,11例出现血气胸,86例患者合并烧伤,96例复合肺吸人性损伤,41例腹部脏器爆震伤,76例并发肺部感染,31例发生休克,7例患者因呼吸衰竭死亡,2例发生多器官功能衰竭.结论 肺爆震伤入院时外伤轻,内伤重,复合伤及并发症多,伤情复杂,诊断困难,胸部X线片表现多样,死亡率高,大部分肺爆震伤患者需气管切开及机械通气,及时气管切开、机械通气是影响预后的主要措施. 相似文献
688.
慢性髓系白血病急变期分子遗传学研究进展 总被引:1,自引:0,他引:1
9号和22号染色体相互易位产生Ph染色体及BCR-ABL融合基因,几乎在所有慢性髓系白血病(CML)出现,BCR-ABL编码的蛋白具有持续增高的酪氨酸激酶活性,使白血病细胞异常增殖。急变期是CML的晚期,在此期间常常出现其它附加染色体和分子的改变。大量研究表明,BCR-ABL基因与其他失调的基因共同作用并异常激活下游的信号传导通路,促进了疾病的进展。酪氨酸激酶抑制剂伊马替尼对大多数慢性期CML患者治疗效果显著。IRIS5年的临床试验显示:用伊马替尼治疗的98%患者达血液学完全缓解,92%患者达主要细胞遗传学缓解,87%患者达完全细胞遗传学缓解。然而,仍有少数慢性期和大多数进展期患者用伊马替尼治疗疗效欠佳。在耐药机制的研究中发现ABL激酶区点突变与临床耐药关系密切。第二代酪氨酸激酶抑制剂可改善伊马替尼耐药,本文就急性变的分子机制、伊马替尼耐药等做一综述。 相似文献
689.
V. G. Nesterenko L. V. Koval'chuk 《Bulletin of experimental biology and medicine》1976,82(3):1372-1374
Transformed lymphocytes obtained by stimulating lymph node cells of CBA mice with phytohemagglutinin (PHA) do not give the graft versus host reaction (GVHR) if injected into sublethally irradiated (CBA×C57BL/6) F1 hybrids. In a population of PHA-stimulated cells the GVHR was induced by small lymphocytes having the same concentration of antigens, detectable by antilymphocytic serum, as intact lymphocytes.Department of Immunology, Medico-Biological Faculty, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR Yu. M. Lopukhin.) Translated from Byulletin' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 9, pp. 1096–1098, September, 1976. 相似文献
690.
A. Ya. Kul'berg F. S. Baranova G. U. Margulis L. K. Popova L. M. Bartova I. A. Tarkhanova 《Bulletin of experimental biology and medicine》1977,84(2):1131-1133
Monovalent and bivalent Fab fragments from normal human and rabbit -globulins were shown to suppress blast transformation of human lymphocytes induced by phytohemagglutinin and concanavalin A. The pepsin F(ab')2 fragments obtained from highly purified rabbit antidinitrophenyl antibodies possess similar properties. An inhibitory action of the fragments was observed when they were added to the culture both simultaneously with and 24 and 48 h after the mitogen. The results may mean that suppression of lymphocyte transformation by fragments of -globulins is not due to their composition with the mitogens for receptors on the target cells; activity of the Fab fragment is evidently determined by structures located outside the combining site of the antibody.N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. Institute of Transplantation of Organs and Tissues, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR P. A. Vershilova.) Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 84, No. 8, pp. 178–181, August, 1977. 相似文献