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1.
FGFR–TACC, found in different tumor types, is characterized by the fusion of a member of fibroblast grown factor receptor (FGFR) tyrosine kinase (TK) family to a member of the transforming acidic coiled-coil (TACC) proteins. Because chromosome numerical alterations, hallmarks of FGFR–TACC fusions are present in many hematological disorders and there are no data on the prevalence, we studied a series of patients with acute myeloid leukemia and myelodysplastic syndrome who presented numerical alterations using cytogenetic traditional analysis. None of the analyzed samples showed FGFR3–TACC3 gene fusion, so screening for this mutation at diagnosis is not recommended.  相似文献   
2.
目的研究单侧液压脑损伤(FPI)对大鼠双侧海马区胶质纤维酸性蛋白(GFAP)表达和CA1区突触传递的影响。方法建立大鼠单侧液压脑损伤模型,脑标本分为对照组(包括正常对照和假手术对照)、FPI损伤同侧组和FPI损伤对侧组。免疫组化法检测海马水平切片GFAP表达,对海马CA1区锥体神经元进行细胞内记录。结果FPI大鼠双侧海马齿状回门区和CA1区GFAP表达均比对照组明显增强。FPI损伤同侧组兴奋性输入-输出关系曲线的斜率比其他两组显著增大(P<0.05);FPI损伤同侧组和对侧组双脉冲易化(PPF)比值和抑制性突触后电位(IPSP)幅值均比对照组显著减小(P<0.05);FPI损伤同侧组和对侧组双脉冲抑制(PPD)比值均比对照组显著增大(P<0.05)。结论大鼠单侧液压脑损伤对双侧海马均可产生影响,导致双侧海马CA1区兴奋性突触传递增强,抑制性突触传递减弱。  相似文献   
3.
目的观察高+Gz重复暴露后脑组织星形胶质细胞中胶质纤维酸性蛋白(GFAP)表达的变化。方法SD大鼠30只,随机分为对照组和+10G;暴露组。+G2暴露组的大鼠暴露于+10Gz/45S,共暴露5次,中间间隔5min。分别于+Gz暴露后不同时间灌注取脑,免疫组织化学染色观察脑GFAP的表达情况。结果+Gz暴露后1d、2d,顶叶皮层、海马GFAP阳性细胞数较对照组均显著增多(P〈0.05),以弱阳性细小型为主;暴露后4d、6d,顶叶皮层、海马GFAP阳性细胞数较对照组进一步增多(P〈0.01),以中等阳性细胞为主,肥大的GFAP增多。结论重复暴露+10Gz/45s可引起大鼠顶叶皮层、海马GFAP表达显著增加。  相似文献   
4.
目的 探讨不同浓度的aFGF对体外培养的大鼠主动脉内皮细胞生长的影响。方法 通过组织块培养法获取主动脉内皮细胞。将浓度为 5ng/ml,10ng/ml,2 0ng/ml的aFGF分别加入内皮细胞的培养液中作为实验组(Ⅰ~Ⅲ组 ) ,不加aFGF的组作为对照组。分别在 2 4h、48h和 72h应用MTT法进行细胞计数。结果 从大鼠主动脉成功地获取了内皮细胞。 3天内 ,实验组和对照组的主动脉内皮细胞都有不同程度的增殖 :培养 2 4h ,实验各组与对照组比较P >0 .0 5 ,无统计学差异 ;48h和 72h时 ,Ⅱ、Ⅲ组与对照组以及与Ⅰ组两两比较 ,有非常显著的差异 (P <0 .0 0 1) ;各时间段内 ,Ⅰ组与对照组 ,Ⅲ组与Ⅱ组比较 ,细胞数改变未见差异 (P >0 .0 5 )。结论 一定浓度的aFGF有非常明显的促血管内皮细胞生长的作用 ,可能对缺血性心脏病的促血管形成治疗有较大的帮助。  相似文献   
5.
Astroglial alterations in rat hippocampus during chronic lead exposure.   总被引:2,自引:0,他引:2  
The present study was performed in order to follow the response of astroglial cells in the rat hippocampus to chronic low-level lead exposure. The experiments combined immunohistochemistry using anti-glial fibrillary acidic protein (GFAP) antibody and conventional transmission electron microscopy (EM). Chronic administration with drinking water [1 g% w/v (subclinical dose) of lead acetate dissolved in distilled water] was started through the mother's milk when pups were 7 days old. Following weaning, experimental offspring were treated for 3 months with the same concentration of adulterated water. The group of intoxicated animals and their controls were sacrificed by perfusion-fixation at 30, 60, and 90 days of exposure. After 60 days of lead treatment, staining of GFAP-positive cells demonstrated an astroglial transformation from the quiescent to the reactive state, characterized by an increase in GFAP. In control rats no changes in GFAP immunostaining were observed. The intensity of the astroglial response was enhanced after 90 days of lead intoxication, showing an increment of GFAP immunoreactivity. Quantification of these changes was made by computerized image analysis, confirming that the sectional areas of the astroglia in lead-exposed animals were larger than those in controls. These results are consistent with the ultrastructural alterations. Simultaneously with the increment in gliofilaments, intranuclear inclusions were seen in some astrocytes. The mechanisms by which lead affects astrocytes are unknown. Probably the astroglial changes induced by lead intoxication produce microenvironmental modifications that may disturb the neuronal function.  相似文献   
6.
Transgenic mice expressing a defined microbial antigen from central nervous system (CNS) cell type-specific promoters can be utilized to investigate the consequences of induction of peripheral immune responses to foreign antigens produced by different CNS cell types. Immunization of mice expressing β-galactosidase (β-gal) in astrocytes with this protein resulted in antigen-dependent infiltration of the CNS by mononuclear cells, principally CD4+ T lymphocytes and monocyte/macrophages. The perivascular and intraparenchymal infiltrates, which were located predominantly in the hippocampal formation and cerebellum, the areas of highest β-gal expression, were associated with astrocytosis, microgliosis, and a generalized increase in blood-brain barrier permeability. The resemblance of these pathological changes to aspects of human immune inflammatory CNS disorders e.g. multiple sclerosis, suggests that an initiating step in the process by which such complex diseases are produced could be the induction of peripheral immune responses to antigens expressed in astrocytes.  相似文献   
7.
Summary The histogenesis of stromal cells in capillary hemangioblastoma has been the subject of debate. The light and electron microscopic studies of hemangioblastomas presented here showed pericytic and leiomyoblastic features in stromal cells. Cells cultured by the monolayer method showed similar features to those of the original tumors. Immunohistochemical studies for glial fibrillary acidic protein and factor VIII/von Willebrand factor indicated that stromal cells were antigenically distinct from astrocytes and endothelial cells. These findings suggest that stromal cells are closely related to pericytes and smooth muscle cells, and support Rhodin's speculation that pericytes serve as a precursor to smooth muscle cells.  相似文献   
8.
目的探讨酸性成纤维细胞生长因子(aFGF)在宫颈癌发生发展中的作用及其信号传导机制.方法应用逆转录-聚合酶链反应技术(RT-PCR)对36例宫颈癌组织aFGF 及其受体FGFR1的表达进行了分析;并以不同浓度的aFGF 和酪氨酸蛋白激酶(TPK)抑制剂genistein诱导宫颈癌细胞株HeLa细胞,[γ-32P]ATP掺入外源性底物的方法,液体闪烁测定蛋白激酶C(PKC)及细胞外信号调节激酶(ERK)的活性.结果 aFGF mRNA 和FGFR1 mRNA在宫颈癌组织中的半定量检测结果分别为(1.233±0.064)和(1.168±0.103),与正常宫颈组织相比,差异有显著性(P<0.05),且在Ⅲ~Ⅳ期宫颈癌中的表达水平明显高于Ⅰ~Ⅱ期(P<0.05);随着aFGF浓度的增加,HeLa细胞PKC及ERK 活性随之升高,与aFGF浓度呈剂量依赖效应;genistein抑制细胞内PKC及ERK 活性,与genistein 浓度亦呈剂量依赖效应.结论提示aFGF 与宫颈癌的发生、发展、浸润呈正相关,其受体具有TPK活性,TPK激活后可进一步激活PKC和ERK,进一步证明PKC及ERK确是TPK的下游信号分子.  相似文献   
9.
目的 :了解急性胰腺炎患者血清免疫抑制酸性蛋白 (IAP)的临床意义。方法 :应用免疫扩散法检测 32例患者和 2 0例健康人中的IAP水平。结果 :正常组 (2 0例 )、轻症组 (2 0例 )和重症组 (12例 )的血清IAP在入院时分别为(32 5± 10 5 )mg/L、(40 4± 15 1)mg/L和 (5 75± 14 5 )mg/L ,重症组血清IAP水平高于正常组 (P <0 .0 1) ,也高于轻症组 (P <0 .0 5 )。其次重症组IAP值在入院后第 3、5、7天与轻症组比较仍明显升高 ,两组有统计上的差异性。结论 :检测IAP可以作为了解急性胰腺炎炎症程度的指标  相似文献   
10.
The edema-producing activity of NNAVPLA2, an acidic phospholipase A2 (PLA2) enzyme from Naja naja atra venom (NNAV), was less potent than that of TMVPLA2 II, a basic PLA; from Trimeresurus mucrosquamatus venom (TMV). These edema-forming effects were greatly suppressed by pretreatment of rats with diphenhydramine/ methysergide or compound 48/80, which reduced the tissue content of histamine and serotonin. Heparin abolished and suppressed the paw edema caused by protamine and TMVPLA2 II, respectively, but had no effect on the NNAVPLA2-induced response. In isolated rat peritoneal mast cells, both PLA2 concentration dependently induced the release of histamine and β-glueuronidase. Again, TMVPLA2 II was more potent than NNAVPLA2. This degranulation effect of mast cells caused by TMVPLA2 II and protamine was inhibited by heparin, while that caused by NNAVPLA2 was unaffected. The edema-forming and mast cell degranulation effects were greatly decreased in both PBPB-modified NNAVPLA2 and PBPB-modified TMVPLA2 II, in which the catalytic activity of the enzymes was completely lost. PBPB-modified TMVPLA2 II-induced paw edema was also suppressed by heparin. Furthermore, this edematous response was totally reversed in rat pretreated with aspirin in combination with diphenhydramine and methysergide. These results suggest that the edema-forming effect of PLA2 is probably dependent on the presence of catalytic, positive charge and pharmacological sites on its molecule.  相似文献   
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