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101.
目的:探讨胞浆抗原在急性白血病免疫分型中的临床意义。方法:用流式细胞仪检测42例初治急性白血病患者胞浆抗原CyCD_3,CyCD_(22),CyCD_(79a)和MPO。结果:T—ALL阳性胞浆抗原主要表达在CyCD_3,阳性率占88.9%。B—ALL阳性胞浆抗原主要表达在CyCD_(79a),AML主要表达CyMPO。结论:CyCD_3和CyCD_(79a),及MPO可分别作为T—ALL,B—ALL和AML系列特异性标志,对正确诊断白血病提供非常有价值的依据。  相似文献   
102.
The clinical, radiological, and pathological features in 10 cases of ganglioglioma are described. The clinical data were derived from the patients' medical records, including a review of the age, sex, details of the presenting symptoms, radiological imagings, surgical intervention, and the clinical outcome. Age ranged from 1 to 66 years (mean 29); there were five males and five females. The tumors were located in the fronto-medial, bifrontal, temporal, temporo-basal, temporo-parieto-occipital, and parietal lobes; the 3rd ventricle; the cervicothoracic spinal cord; and the conus medullaris. The presenting symptoms were focal seizures, headaches, hemiparesis, paraparesis, and tetraparesis. In four patients, gross total resection was achieved and in the remaining six patients only subtotal resection was possible. Tumor recurrence occurred in three patients, 1 year, 14 months, and 2 years after the first operation. The histopathologic appearance of gangliogliomas showed a broad variation of the neuronal, glial, and stromal component. Studying proliferation characteristics, labeling for Ki-67 ranged from 0 to 13.7% (mean 4.1) and for PCNA from 0 to 32.1% (mean 20.4). Due to their favorable prognosis, early recognition and correct diagnosis are important in order to avoid progressive neurological deficits and unnecessary aggressive therapy. The application of immunohistochemistry for both neuronal (synaptophysin, NSE, NFP) and astrocytic (GFAP) cell markers, as well as proliferation markers, are recommended in the diagnostic setting for gangliogliomas. The treatment of choice is total surgical resection. The role of radio- and chemotherapy is still controversial.  相似文献   
103.
Synthetic fragment of human interferon-2α (124th–138th amino acid residue, laboratory code 2438) inhibits the growth of B lymphocytes (Daudi cell line) in a dose-dependent manner. Radiolabeled peptide 2438 binds to specific receptors on the cell surface and competes with interferon-2α for the common binding sites. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 123, No. 4, pp. 446–448, April, 1997  相似文献   
104.
采用液氮冷冻Wistar大鼠-侧大脑制成血管源性脑水肿模型,将大怀脑冷冻中心制成冠状面冰冻切片,运用免疫组化染色观察脑水肿组及对照组白质脑屏障内皮细胞表面ICAM-1蛋白表达量的变化 。  相似文献   
105.
天麻素对缺血再灌注神经细胞膜的保护作用   总被引:36,自引:0,他引:36  
用新生Wistar大鼠大脑皮层进行神经细胞培养 ,将培养 8d的神经细胞置于模拟“缺血”状态下 ,5h后神经细胞发生肿胀 ,胞内乳酸脱氢酶 (LDH)漏出增加 ,膜流动性下降、脂质过氧化(LPO)含量增加 ;将经过“缺血”损伤神经细胞置 1 8h模拟“再灌注” ,“再灌注”后细胞数目明显减少 ,LDH的漏出、膜流动性下降和LPO增加继续加重 ,说明细胞损伤进一步加重。经过天麻素孵育后的神经细胞“缺血”或“再灌注”后LDH的漏出及LPO含量明显低于损伤组 ,而膜流动性则明显高于损伤组。表明 :天麻素对体外培养神经细胞的缺血再灌注损伤有保护作用  相似文献   
106.
陈书盘  耿沁 《肿瘤》1997,17(5):258-261
目的评价检测CYFRA21┐1对非小细胞肺癌的诊断价值。方法用ELISA法测定70例肺癌(LC)其中47例非小细胞肺癌(NSCLC),3例小细胞肺癌(SCLC)和20例未分型肺癌、64例肺部良性疾病患者及40例健康人血清CYFRA21┐1浓度。试验的诊断性能用相对操作特征(ROC)分析法估测之。结果测得全阈诊断准确率(OveralDiag┐nosticAccuracies)LC为0.75、NSCLC为0.76,SQC为0.83,ADE为0.67和SCLC为0.38。在相应于特异性为0.95的界定值3.47μg/L处,各型的灵敏度分别为SQC0.62,LC0.53,NSCLC0.51,ADE0.48和SCLC0.00。结论结果显示CYFRA21┐1是NSCLC较灵敏和特异的一个标志物。未观察到TNM各期间该标志物的平均水平有明显的差异;然而异常升高水平的患者的比例随病期的进展而显著增加,提示一系列检测CYFRA21┐1水平可能有助于监查NSCLC患者的疗效。  相似文献   
107.
CO作用后大鼠肺血管细胞增殖和凋亡状况的研究   总被引:2,自引:0,他引:2  
目的:通过研究CO和低氧作用后大鼠肺血管细胞增殖和凋亡状况,探讨低氧肺动脉高压的发病机制及防治措施。方法:应用免疫组织化学,原位末端标记及Western杂交等方法检测常压低氧大鼠肺血管壁细胞增殖,凋亡及c-myc基因的表达状况。结果:正常组,低氧和锡原卟啉组,低浓度CO和血晶素组大鼠肺动脉均存在增殖和凋亡的阳性细胞,两类细胞在肺内呈不均匀散在分布,低氧和锡原卟啉组大鼠肺血管增殖细胞数显著升高而凋亡细胞数显著减少,细胞增殖凋亡比值分别为对照组的5倍或4倍,而低浓度CO和血晶素组肺血管增殖细胞和凋亡细胞系数均显著增加,细胞增殖凋亡比值均为1.2,c-myc在低氧和锡原卟啉组大鼠肺内表达显著增加,在低浓度CO和血晶素组大鼠肺内表达减少。结论:增殖和凋亡现象共存在于正常和处理大鼠的肺血管细胞中,也许c-myc等基因的异常表达导致了细胞增殖和凋亡的失衡,进而调节了慢性低氧肺血管结构的改建。  相似文献   
108.
Embryonic cholinesterases are assigned important functions during morphogenesis. Here we describe the expression of butyrylcholinesterase and acetylcholinesterase, and the binding of peanut agglutinin, and relate the results to mitotic activity in chick wing and leg buds from embryonic day 4 to embryonic day 9. During early stages, butyrylcholinesterase is elevated in cells under the apical ectodermal ridge and around invading motoraxons, while acetylcholinesterase is found in the chondrogenic core, on motoraxons and along the ectoderm. Peanut agglutinin binds to the apical ectodermal ridge and most prominently to the chondrogenic core. Measurements of thymidine incorporation and enzyme activities were consistent with our histological findings. Butyrylcholinesterase is concentrated near proliferative zones and periods, while acetylcholinesterase is associated with low proliferative activity. At late stages of limb development, acetylcholinesterase is concentrated in muscles and nonexistent within bones, while butyrylcholinesterase shows an inverse pattern. Thus, as in other systems, in limb formation butyrylcholinesterase is a transmitotic marker preceding differentiation, acetylcholinesterase is found on navigating axons, while peanut agglutinin appears in non-invaded regions. These data suggest roles for cholinesterases as positive regulators and peanut-agglutinin-binding proteins as negative regulators of neural differentiation.  相似文献   
109.
Summary Cell proliferation of 51 human renal cell carcinomas and 9 larynx and hypopharynx carcinomas has been studied in vitro and using xenotransplants. The proliferative activity ([3H]thymidine labelling index) increases during the first passages in nude mice and then remains almost constant throughout subsequent passages. A comparison of cell kinetic parameters of 8 human renal cell carcinomas, 1 hypopharynx and 2 larynx carcinomas, with data of xenografts and of human tumours in situ published up to now, shows that the cell kinetic parameters of human tumour xenografts presently studied range between those of human tumours in situ and those of autochthonous or transplantable mouse tumours. S-phase durations and potential doubling times are considerably shorter in xenotransplants than in human tumours in situ, whereas the cycle time is about the same. This means that the growth fraction increases considerably after xenotransplantation. This change of human tumour cell proliferation after transplantation into nude mice should be kept in mind if one wishes to draw conclusions from the nude mouse model on conditions in human beings, particularly with respect to therapeutic regimens, which are frequently tested in the nude mouse model.Abbreviations used RCC renal cell carcinoma - HPC larynx or hypopharynx carcinoma - LI labelling index - PLM percentage of labelled mitoses - t s S-phase duration - t c cycle time - t pot potential doubling time This work was supported by the Deutsche Forschungsgemeinschaft (Ma 876/2-1)  相似文献   
110.
Interleukin (IL)-2 and IL-4 are considered as important regulators of growth and differentiation of lymphocytes. We report that in mice made deficient for both IL-2 and IL-4 by gene targeting all major T cell subsets and B cells were normal, indicating that IL-2 and IL-4 are not essential for development of the immune system. Paradoxically, proliferation of T cells was increased in both IL-2- and IL-4-deficient homozygous mice.  相似文献   
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