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1.
MACS检测胃癌腹腔冲洗液游离癌细胞的研究   总被引:2,自引:1,他引:1       下载免费PDF全文
目的 探讨胃癌腹腔微转移情况的检测方法及意义。方法 手术中切除肿瘤前收集腹腔冲洗液,采用磁激活细胞分离术(MACS)对不同病理分期胃癌患者腹腔冲洗液中癌细胞进行富集并检测。分别标记带磁珠的细胞角蛋白(CK)抗体,经磁柱富集CK^+上皮细胞,用流式细胞仪检测其含量,并比较胃癌组与胃平滑肌瘤组(对照组)以及胃癌不同分期之间、磁富集前后CK^+上皮细胞含量的差异。结果 在未经MACS富集的标本中较少发现CK^+ CD45^-细胞;在富集后的标本中其含量在胃癌组与对照组有显著差异(41/50,1/10,P〈0.001);pTNMⅠ~Ⅱ期与Ⅲ~Ⅳ期之间(0.67%,3.42%,P〈0.001)差异有非常显著性。结论 MACS能有效地富集上皮来源细胞,提高上皮源细胞的检出率,并能反映腹腔游离癌细胞数量;上皮细胞数量与胃癌的存在及临床病理分期有关,其有利于判断肿瘤转移和预后并指导治疗。  相似文献   
2.
Alcoholic patients often have impaired immune function, yet little is known about the precise mechanism(s) of this impairment. We have previously shown that ethanol consumption by mice alters copolymer-specific humoral and cellular immune responses. In this study, we asked whether alcohol consumption by mice would phenotypically alter lymphocyte populations. Female C57BL/6 mice were fed a nutritionally complete liquid diet containing 35% ethanol-derived calories for up to 8 days. As controls, mice either were fed a liquid control diet that isocalorically substitutes sucrose for ethanol or remained on a standard solid diet and water ad libitum. Although mice fed ethanol-containing liquid or pair-fed control liquid diets have decreased numbers of spleen cells compared with solid diet controls, only the ethanol-containing diet allowed normally nonresponder C57BL/6 spleen cells to make antibody responses to the poly(Glu50Tyr50) synthetic copolymer antigen. Flow cytometric analysis of splenic lymphocyte populations of mice on the ethanol-containing diet shows an increase in the relative proportion of T-lymphocytes as compared with mice on either solid or liquid control diets. No such change is seen for either B-cell or natural killer cell populations in these same mice. Both liquid control and liquid ethanol diets caused a slight decrease in the CD4:CD8 ratios of splenic T-lymphocytes. We see the relative percentage of T-cells bearing the αβ-cell receptor (TcR) increases in the spleens of liquid ethanol diet mice; a smaller increase TcRαβ usage is seen in the spleens of liquid control mice, compared with solid diet mice. Flow cytometric analysis shows that little, if any, difference exists in TcRγδ expression between the liquid ethanol and either the liquid control or solid diet groups. Preliminary analysis of TcRαβ subsets suggest that ethanol increases the percentage of T-cells expressing Vβ5 and Vβ8, and decreases the percentage of Vβ11 expressing cells. These findings suggest that, in addition to modifying the immune response, ethanol alters the phenotypic expression of lymphocyte subsets.  相似文献   
3.
本文报道了一种实体组织用于DesoxyribonucleicAcid(DNA)分析的Flowcy tometry(FCM) )样品保存新方法 ,即新鲜组织块乙醇直接固定法。所用样品为头颈部肿瘤手术切除的新鲜标本 3 0例 ,每例标本重约 0 5~ 1 g ,均等分为两份 ,1份置 70 %乙醇直接固定 ,室温放置 ,待两年后FCM检测。另一份置生理盐水中立即行流式细胞术DNA分析。两组样品经机械法制成单细胞悬液 ,PI染色后上机检测。结果显示 :从两组样品的DNA直方图分析 ,CV(coefficiencyofvariation)值、GO/G1、S及G2 /M各期比率无显著差异 (P >0 0 5)。我们认为在样品收集短期内难以完成 ,需积累保存 ,或需保存半年以上者 ,且不具备低温冷冻设备的条件下 ,新鲜组织块乙醇直接固定法是优于将组织块先制备成单细胞悬液再行乙醇固定的流式细胞术DNA样品保存方法  相似文献   
4.
Apoptosis is a programmed, physiologic mode of cell death that plays an important role in tissue homeostasis. As for the central nervous system, ischemic insults can induce pathophysiologic cascade of apoptosis in neurophils. Impairment of astrocyte functions during brain ischemia can critically influence neuron survival by neuronglia interactions. We aimed to elucidate the protective effect of ketamine on apoptosis by energy deprivation in astrocytes. Ischemic insults was induced with iodoacetate/ carbonylcyanide m-chlorophenylhydrazone (IAA/CCCP) 1.5 mM/20 microm or 150 microm/2 microm for 1 hr in the HTB-15 and CRL-1690 astrocytoma cells. Then these cells were reperfused with normal media or ketamine (0.1 mM) containing media for 1 hr or 24 hr. FITC-annexin-V staining and propidium iodide binding were determined by using flow cytometry. Cell size and granularity were measured by forward and side light scattering properties of flow cytometry system, respectively. An addition of ketamine during reperfusion increased the proportion of viable cells. Ketamine alleviated cell shrinkage and increased granularity during the early period, and ameliorated cell swelling during the late reperfusion period. Ketamine may have a valuable effect on amelioration of early and late apoptosis in the astrocytoma cells, even though the exact mechanism remains to be verified.  相似文献   
5.
A system effective in the early diagnosis of Dengue virus infection was developed. The time course kinetics of Dengue virus type 2 (D-2) antigen in vitro were analyzed by Flow Cytometry. Early profiles of D-2 were also studied quantitatively through this method of analysis. The early events of host cell and virus interaction were investigated: attachment, internalization and replication. From these early profiles, the time at which new viral synthesis was detectable differed with each individual trial. These different times were found to be dependent of the phase of the cell cycle. From these results we could detect newly synthesized viral antigen within 10 h after infection.  相似文献   
6.
 目的 探讨环氧化酶 2 (COX 2 ) ,Ⅱ型一氧化氮合酶 (iNOS)基因蛋白在食管癌上的表达以及与食管癌的分化和淋巴结转移的关系。方法 采用流式细胞术定量检测 6 5例食管鳞状细胞癌上COX 2、iNOS的蛋白表达量 (用荧光指数FI表示 )。结果 COX 2、iNOS在低分化型 (G3)鳞癌上的表达量明显高于分化型 (G1、G2 )鳞癌 (其P值分别为 0 .0 0 0 1、0 .0 385 ) ;二者之间呈明显正相关。这两种基因蛋白的表达强弱均与淋巴结转移无关。结论 COX 2、iNOS的表达强弱与食管癌的分化密切相关 ;COX 2与i NOS在促食管癌的发生发展中有互相协同作用  相似文献   
7.
目的 :探索及检测宫颈癌细胞株 Caski、 Si Ha细胞内 HPV1 6 (16型人乳头瘤病毒 ) E6 /E7蛋白含量 ,筛选宫颈癌基因治疗研究的合适细胞株。方法 :用间接免疫荧光染色及流式细胞术检测 Caski、 Si Ha宫颈癌细胞株中 HPV1 6 E6 、 HPV1 6E7蛋白含量 (荧光强度值 )。结果 :Caski细胞中 HPV1 6 E6 、 HPV1 6 E7蛋白含量分别为 :2 0 .72± 6 .35、 5 6 .80± 4 .30 ;Si Ha细胞中 HPV1 6 E6 、E7蛋白含量分别为 :1.77± 0 .75、 4 9.2 7± 8.0 6。 2细胞株间 HPV1 6 E7蛋白表达量无明显差异 (P>0 .0 5 )。结论 :Caski、Si Ha宫颈癌细胞株中 HPV1 6 E6 、E7蛋白的表达是不平行的。Caski细胞适用于以 HPV1 6 E6 ,HPV1 6 E7蛋白为观察对象的研究 ,Si Ha细胞可用于 HPV1 6 E7蛋白的研究 ,但不适宜用于以 HPV1 6 E6 蛋白为观察对象的研究。  相似文献   
8.
周文  谭继全  吴平 《中国校医》2006,20(1):18-20
目的探讨声门上型喉癌患者手术前是否存在Th1/Th2免疫失衡及根治性切除肿瘤后能否使Th1/Th2恢复平衡。方法用流式细胞仪检测48例根治切除的声门上型喉癌患者术前、术后不同时期外周血淋巴细胞亚群中各种细胞因子表达。结果能代表Th1功能的IL-2、IL-12和IFN-γ术后的表达水平较术前明显升高(P〈0.01);能代表Th2功能的IL-4和IL-10术前的表达水平远高于术后,差别均具有显著意义(P〈0.01)。如IL-4和IL-10术后的表达水平与术前无差异,提示癌瘤复发或转移的可能性大。结论声门上型喉癌患者手术前即存在Th1/Th2免疫失衡,行根治性肿瘤切除可解除免疫抑制,改善患者细胞免疫功能而促使TH1/TH2免疫恢复平衡。  相似文献   
9.
bcl-2、p53在皮肤肿瘤中的表达及意义   总被引:1,自引:0,他引:1  
目的探讨bcl-2、p53在几种皮肤肿瘤中的表达及意义。方法采用流式细胞术(FCM)和免疫荧光技术对皮肤鳞状细胞癌(SCC)、恶性黑色素瘤(MM)、基底细胞癌(BCC)、色素痣(PN)bcl-2、p53蛋白的表达进行定量分析,以荧光指数(FI)作为定量表达指标。结果鳞状细胞癌、基底细胞癌的bcl-2、p53基因蛋白的FI值均显著性高于正常对照(P<0.05),基底细胞癌的bcl-2基因的FI值显著性高于鳞状细胞癌(P<0.05),而二者的p53基因蛋白的FI值无显著性差异(P>0.05);恶性黑色素瘤、色素痣的bcl-2、p53基因蛋白的FI值均显著性高于正常对照(P<0.05),恶性黑色素瘤的p53基因的FI值显著性高于色素痣(P<0.05),而二者的bcl-2基因蛋白的FI值无显著性差异(P>0.05)。结论鳞状细胞癌、恶性黑色素瘤、基底细胞癌、色素痣中均有bcl-2的表达,基底细胞癌bcl-2表达显著高于鳞状细胞癌,说明基底细胞癌的发生发展可能与细胞凋亡受抑密切相关;p53在恶性黑色素瘤的表达高于色素痣,说明p53为黑色素瘤的恶性标志,检测p53表达可以作为鉴别皮肤黑色素瘤恶性病变的辅助手段。  相似文献   
10.
《Human immunology》2016,77(6):449-455
Pronase treatment is used in the flow cytometry crossmatch (FCXM) to prevent nonspecific antibody binding on B cells. However, we have observed unexpected positive results with pronase-treated T cells in human immunodeficiency virus (HIV)-infected patients. In this study, 25 HIV-infected patients without HLA antibodies were tested with pronase-treated and nontreated cells. HIV-positive sera were pretreated with reducing agents and preabsorbed with pronase-treated and nontreated T or B cells before crossmatching. All patients displayed FCXM reactivity with pronase-treated T cells but not with nontreated T cells. None of the patients exhibited FCXM reactivity with pronase-treated and nontreated B cells. These patients displayed FCXM reactivity with pronase-treated CD4+ and CD8+ T cells but not with their nontreated counterparts. Preabsorption with pronase-treated T cells reduced the T cell FCXM reactivity. Preabsorption with pronase-treated B cells or nontreated T and B cells did not have any effect on the T cell FCXM reactivity. Pretreatment with reducing agents did not affect the T cell FCXM reactivity. 15 of 21 HIV-infected kidney allograft recipients with pronase-treated T cell FCXM reactivity display long-term graft survival (1193 ± 631 days). These data indicate that HIV-infected patients have nondeleterious autoantibodies recognizing cryptic epitopes exposed by pronase on T cells.  相似文献   
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