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21.
22.
PROSTATE-SPECIFIC ANTIGEN AS A TUMOR MARKER IN PROSTATE CANCER 总被引:3,自引:0,他引:3
Manabu Kuriyama 《International journal of urology》1994,1(2):99-113
23.
乳腺囊性增生病癌变过程中部分因素变化的意义 总被引:3,自引:0,他引:3
检测乳腺囊性增生病(FCD)经不典型增生到癌变部分因素的变化。结果提示:从因明显FCD症状活检至癌变为2~10年;从Ⅱ级以上不典型增生到临床癌变需2~7年;癌变率为3.1%。FCD患者存在性激素分泌调控失常,血浆雌激素和催乳素含量增加,导致上皮细胞增生。乳腺一般性增生细胞的DNA含量和超微结构与正常乳腺上皮细胞相似;无肿瘤相关抗原及异常基因产物表达。而发生在一般性增生基础上的不典型增生则呈现细胞基因物质DNA含量增加,部分为超4C的多倍体细胞;同时出现细胞膜和细胞核超微结构异常;雌激素受体含量增加,对性激素的依赖性和敏感性增强;部分不典型增生细胞出现胚胎性肿瘤相关抗原和异常基因产物表达。随不典型增生程度加重至乳腺癌,上述诸因素的变化趋势具有明显规律性。提示FCD上皮细胞从一般性增生经不典型增生至乳腺癌为细胞生物学连续逐渐变化的过程。部分不典型增生细胞中具有癌倾向的细胞生物学行为异常和表型变化与乳腺癌发生密切相关。细胞核DNA含量等异常变化及程度可作为乳腺癌前病变发展程度的客观标志 相似文献
24.
The presence of class 1 and class 2 histocompatibility antigens on murine sperm was investigated by flow microfluorometry. Monoclonal anti-H-2Kk (class 1), anti-Iak (specificity 2, class 2) and allo-anti-Iak (class 2) antisera were used in direct or indirect fluorescence labelling experiments to probe the expression of class 1 and class 2 antigens on epididymal mouse spermatozoa. Sperm-specific antibodies were generated by intraperitoneal immunization of both male and female C3H/HeN mice with syngeneic spermatozoa. Sperm-specific antigens were detected in 68-85% of syngeneic mouse sperm and 65-90% of allogeneic mouse sperm examined. Conversely, these antibodies did not stain syngeneic or allogeneic lymphocytes above the background of the negative control. Mouse sperm samples failed to exhibit specific fluorescence above the background of negative control values with antibodies against either class 1 or class 2 MHC antigens. We have established the sensitive, objective and economical assay of sperm membrane antigens with fluorochrome-labelled antibodies by flow microfluorometry. By use of this sensitive and objective technique we have not detected MHC antigens on murine sperm. We conclude that these MHC antigens are not expressed on sperm at a level to be practically detectable. 相似文献
25.
肿瘤-睾丸抗原基因在肾透明细胞癌中的表达 总被引:1,自引:1,他引:0
目的 研究6种肿瘤.睾丸抗原(CT)基因在肾透明细胞癌中的表达及其临床意义.方法 采用逆转录-聚合酶链反应(RT-PCR)技术检测42例肾透明细胞癌患者癌组织(新鲜标本,T1期16例,12期12例,T3期10例,T4期4例;G1 10例,G2 18例,G3 14例)及其中14例患者癌旁组织的cTAGE-1、cTAGE-2、MAGE-A1、MAGE-A3、MAGE-A12及NY-ESO-1基因mRNA的表达.结果 42例肾透明细胞癌组织中100%(42/42)至少表达6种CT基因中一种,14例癌旁组织表达均阴性.肾透明细胞癌组织中MAGE-A12表达最高,其次为MAGE-A3,MAGE-A1,cTAGE-1,cTAGE-2及NY-ESO-1,分别为71%(30/42),69%(29/42),67%(28/42),64%(27/42),60%(25/42)及48%(20/42).肿瘤不同分期、不同分级之间6种CT基因表达的差异均无统计学意义(Pearson x2检验法,P>0.05).结论 CT基因在肾透明细胞癌中有较高表达,可望成为肾透明细胞癌特异性免疫治疗的靶基因. 相似文献
26.
Z. Peng Q. Liu Q. Wang E. Rector Y. Ma R. Warrington 《Clinical and experimental allergy》2007,37(7):1040-1048
BACKGROUND: Immunotherapy with anti-IgE antibodies for treatment of allergy is promising but a short half-life and extremely high cost limit its application. OBJECTIVE: We sought to develop IgE vaccines that induce longer-lasting auto-antibodies to neutralize self-IgE as an alternative therapy. METHODS: The vaccine was made by conjugating three synthetic peptides corresponding to human IgE receptor-binding sites to a carrier, hepatitis B surface antigen. To test the immunogenicity of the vaccine, rats were immunized with the vaccine or hepatitis B surface antigen as control. Serum IgG titres to human IgE and the IgE of other species were measured. The inhibition by rat antisera of the binding of human IgE to its receptor was assessed by ELISA, flow cytometry analysis, and passive cutaneous anaphylaxis (PCA), and its ability to recognize receptor-bound IgE was examined. The in vivo effect of the vaccine was evaluated in trichosanthin-sensitized mice and rats. In the preventative study, vaccination started before sensitization commenced, while in the treatment study, vaccination started after sensitization. Sensitized mice and rats receiving injections of the carrier served as controls. Trichosanthin-specific IgE was measured using PCA. RESULTS: Sera from vaccine-immunized rats contained high titre antibodies that reacted with soluble and plate-bound but not with receptor-bound human IgE; they also reacted with mouse, rat, and dog IgE. Furthermore, the sera inhibited the binding of human IgE to its receptor in a dose-dependent manner. In preventative and treatment studies, serum trichosanthin-specific IgE levels were significantly reduced in vaccinated groups compared with controls. CONCLUSION: Antibodies against self-IgE can be induced by IgE peptide-based vaccines, which are effective in preventing the increase of IgE and in down-regulating IgE in sensitized animals. 相似文献
27.
AMAL KANBOUR-SHAKIR DAVID T. ARMSTRONG ANNE ROULEAU HEINZ W. KUNZ THOMAS J. GILL 《American journal of reproductive immunology (New York, N.Y. : 1989)》1995,33(5):367-372
PROBLEM : To determine whether seminal fluid influences the expression of MHC class I antigens on the surface of basal trophoblast cells in the placenta of the rat. METHODS : Transfer of DA × DA embryos into a WF (allogeneic) or DA (syngeneic) recipient made pseudopregnant by hormonal treatment followed by mating with a vasectomized male (seminal fluid) or by mechanical stimulation (no seminal fluid). Antigen expression was determined by electron microscopic immunocytochemistry using the appropriate gold-labeled monoclonal antibodies. RESULTS : Seminal fluid did not affect the expression of MHC class I antigens on the surface of the basal trophoblast in either allogeneic or syngeneic matings. CONCLUSIONS : The suppression of the expression of paternal class I antigens on the surface of the basal trophoblast cells in allogeneic pregnancies most likely occurs at the genome level shortly after fertilization. 相似文献
28.
作者应用免疫细胞化学法研究了HFRS尸检内分泌及其有关组织中病毒抗原的分布,病毒抗原阳性细胞与病变的关系,病变的类型及病毒感染对胰腺内胰岛素表达的影响,所用的一抗有抗肾综合征出血热(HFRS)病毒糖蛋白(G_2),核蛋白(NP)及血凝素(HA)抗原的单克隆抗体(15种)和多克隆抗体(PAb)以及抗胰岛素(INS)单克隆抗体。结果显示,内分泌组织中有两种染色形态的病毒抗原,一种是胞浆弥漫染色的抗原,为G_2,NP或HA阳性,阳性细胞弥漫分布,另一种是以病毒包涵体(IB)形式出现的颗粒性抗原,MAbs染色多为实性,PAb染色多为空泡状。在9例胰腺组织中,有4例几乎在所有腺上皮细胞和少数胰岛细胞均为IB阳性,但PAb染色可在胰岛细胞中显示出空泡状IB。在其它内分泌组织中,IB只在少数细胞中出现。抗原阳性细胞很少出现坏死,但在脑垂体及肾上腺灶性或片状凝固性坏死区域也有弥漫性抗原阳性及IB存在。胰腺组织的胰岛素染色显示,除1例胰岛INS强阳性,其余8例均有明显的INS染色减弱及阳性细胞减少的表现。结果提示,内分泌组织中有两种病变,即以IB为特征的病毒直接感染引起的细胞病变,是病毒的弱致病变作用,该病变可能对细胞的内分泌功能产生影响;另一种病变是组织的灶性或大片性同步性凝固性坏死,是继发于病毒感染后的出血和休克,该病变会 相似文献
29.
FIONA TOMLEY 《Parasite immunology》1994,16(8):407-413
Total polypeptides from unsporulated and sporulated oocysts, sporozoites and the first two generations of merozoites of Eimeria tenella were fractionated by electrophoresis through polyacrylamide gels. The parasites are complex and the arrays of polypeptides differ for each of the developmental stages indicating that there is stagespecific control of gene expression. In particular, first generation merozoites display a markedly different polypeptide profile to that of either sporozoites or second generation merozoites. Changes in antigenicity during sporulation and the antigenic relationships between the three asexual zoite stages were examined by probing electroblotted polypeptides with a panel of antisera raised in rabbits to purified preparations of each stage. Antigenic cross-reactivity is well maintained throughout sporulation even though the sizes of antibody-reactive polypeptides change. In contrast there is a marked lack of cross-reactive epitopes between sporozoites, first and second generation merozoites. 相似文献
30.
前列腺体积与前列腺特异抗原及抗原密度关系的多元回归研究 总被引:1,自引:0,他引:1
对100例前列腺增生患者的前列腺体积,年龄,血清前列腺特异抗原,抗原密度进行多元回归与相关分析。结果;年龄和前列腺体积与血清PSA浓度显著相关,其中,体积与PSA之间的年龄与体积之间具有相关性、而年龄与PSA之间无相关性,体积每增加10cm^3,PSA增高0.9μg/L。 相似文献