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101.
人碱性成纤维细胞生长因子基因在大肠杆菌中的克隆与表达 总被引:1,自引:0,他引:1
应用DNA重组技术将编码人碱性成纤维细胞生长因子(bbFGF)的基因克隆至原核高效表达质粒pBV_(221)的启动子下游。SDS-SAGE、ELISA和NTT活性监测结果表明:该重组质粒pBV-hbFGF在大肠杆菌DH5α中,经42℃诱导后,可表达出有较高生物活性的hbFGF。 相似文献
102.
Variation of prostate-specific antigen expression in different tumour growth patterns present in prostatectomy specimens 总被引:3,自引:0,他引:3
M. P. W. Gallee E. Visser-de Jong J. A. G. M. van der Korput Th. H. van der Kwast F. J. W. ten Kate F. H. Schroeder J. Trapman 《Urological research》1990,18(3):181-187
Summary A series of 55 randomly chosen radical prostatectomy specimens was analyzed for expression of prostate-specific antigen (PSA) by immunohistochemical techniques. Tissue sections were selected in such a manner that in addition to glandular benign prostatic hyperplasia (BPH), one or more different prostatic tumour growth patterns were present. Four monoclonal antibodies, directed against three different PSA epitopes, and one polyclonal anti-PSA antiserum were used. Expression of PSA was compared with that of prostate-specific acid phosphatase (PAP), recognized by two different polyclonal antisera. A critical dilution aimed at a maximum of staining intensity on BPH tissue sections was chosen for all antibodies. Anti-PSA and anti-PAP antisera stained essentially all BPH samples (over 90%). Irrespective of the nature of the antibodies used, PSA expression was found to be decreased in prostatic carcinoma. A clear cut relationship was found between immunoreactivity for PSA and the degree of differentiation of the tumour area. Under the experimental conditions used the PSA monoclonal antibodies stained only 1 out of 10 undifferentiated carcinomas, whereas 50% to 70% of the well- and moderately-differentiated carcinomas showed immunoreactivity. This correlation was less pronounced with the PAP staining pattern. If the PSA antibody titer was raised the percentage of clearly staining undifferentiated carcinomas could be considerably increased (up to 60%–100%), indicating that PSA expression is not absent, but lowered in most (if not all) undifferentiated carcinomas. 相似文献
103.
Masami Yoshida Hideyasu Yokoo Kimihiro Nakahara Masaru Tomita Naoyuki Hamada Michiko Ishikawa Jyunko Hatakeyama Masatoshi Tanaka Ikuko Nagatsu 《Brain research》1997,767(2):87
Infusion of muscimol (5×10−5 M, 60 min) into the nucleus accumbens (NAC) through a dialysis membrane caused a significant increase in extracellular dopamine (DA) and its metabolite, 3,4-dihydroxyphenylacetic acid (DOPAC). Fos-like immunoreactivity induced by intra-NAC infusion of muscimol was seen ipsilaterally in many accumbofugal target areas, but no Fos-positive neurons were seen in the vicinity of the dialysis membrane in the NAC. Sequential staining of Fos and tyrosine hydroxylase (TH) immunoreactivities revealed that a portion of A10 dopaminergic neurons were double-labelled. These results suggest that muscimol in the NAC disinhibits mesolimbic DA neuronal activity possibly through activity of the accumbofugal GABA neuron system. 相似文献
104.
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
105.
介绍一种用单片机构成的自动灌流控制系统。它以灌流压为控制指标,以LDB-M电子蠕动泵作为执行机构,构成闭环控制系统,能实现用户设定的各种液流压曲线。系统内采用了EEPROM存储器,可对用户设定的多达10条灌流曲线进行长期保存。 相似文献
106.
钩体基因疫苗对豚鼠延髓原癌基因表达的影响 总被引:1,自引:1,他引:0
我们的研究已表明,赖型017株钩体外膜疏水蛋白OmpL39是稳定的免疫原,在此我们分别用OmpL39与钩体死菌苗和生理盐水对照免疫豚鼠,研究OmpL39的免疫保护作用和免疫机理,对OmpL39的抗原特异性刺激引起中枢原癌基因(Cfos基因)表达进行了观察。结果表明,OmpL39在豚鼠体内能产生高效价的阳性抗体,免疫保护率为100%。在OmpL39对中枢Cfos基因表达的影响中,我们观察到OmpL39免疫的豚鼠较空白和死菌苗组Cfos表达明显少于死菌苗组和空白对照组(p<005)。提示OmpL39能特异性地抑制Cfos基因的表达,减轻强毒钩体对动物体内的病理损伤,有较死菌苗强的免疫保护作用。 相似文献
107.
肉鸡对不同形态锰源的生物利用率研究 总被引:9,自引:0,他引:9
目的 : 研究肉仔鸡对不同形态锰源的相对生物学利用率。方法 : 将 62 4只 1日龄肉公鸡随机分为 1 3组 ,分别饲不添加锰的基础饲粮 (对照组 )或以不同锰化合物添加 60、1 2 0、1 80 mg/ kg锰的试验饲粮 2 1 d。结果 : 肉鸡生长性能各指标和腿病发生率以及肉鸡的跖骨灰锰含量、心肌细胞线粒体中 Mn SOD活性均未受到添加锰源以及锰源与锰水平互作的显著影响 ,但受到添加锰水平的显著影响。肉鸡心肌含锰量和 Mn SOD m RNA水平均未受到添加锰源与锰水平互作的显著影响 ,但受到添加锰源及添加锰水平的显著影响。其中中等和强络合强度有机锰源的生物学利用率明显高于无机硫酸锰和弱络合强度有机锰源。结论 : 中等和强络合强度的复合氨基酸锰对肉仔鸡的生物学利用率明显优于无机硫酸锰和弱络合强度的蛋氨酸锰 相似文献
108.
Summary. The expression of adhesion molecules on human spermatozoa of healthy probands was analysed. The localization patterns of adhesion molecules (AM) on the spermatozoal surface were documented by fluorescence microscopy. Spermatozoa were incubated with antibodies against α1 (CD49a), α2 (CD49b), α3 (CD49c), α4 (CD49d), α5 (CD49e), α6 (CD49f) chains of β1 integrins, β1 (CD29), β2 (CD18), αV (CD51), β3 (CD61) and β4 integrin chains, the LFA-3 (Lymphocyte function antigen, CD58) from the immunoglobulin superfamily and the extracellular matrix proteins laminin, fibronectin and collagen IV. For collagen IV, α1 and α2 chains no expression could be noticed. Laminin was detected at the acrosomal membrane, fibronectin and β4 chain mainly at the equatorial membrane. The fibronectin receptors α3, α4 and α5 chains of the β1 integrins were mainly located on acrosomal and equatorial membrane areas. Laminin receptor α6 chain was located postacrosomal and less frequently acrosomal. β2 chain and vitronectin receptors αV and β3 chains had a mainly postacrosomal localization pattern. LFA-3 was found constantly on postacrosomal membrane areas. Double staining technique was used to prove the simultaneous occurrence of fibronectin and its integrin receptors α3, α4 and α5 chains and of αV and β2 chains on spermatozoa. The localization patterns of integrins on double stained spermatozoa were similar to the patterns described for single stained spermatozoa. The localization of fibronectin appeared to be influenced by the presence of integrins: the typical equatorial fibronectin band disappeared in case of an equatorial localization of integrins. 相似文献
109.
PTEN基因在喉鳞癌中的表达及意义 总被引:2,自引:0,他引:2
目的:探讨蛋白酪氨酸磷酸酶基因(PTEN)在喉鳞癌中的表达及其临床意义.方法:应用半定量RTPCR方法检测喉癌组织中PTEN mRNA的表达.结果:淋巴结转移组喉癌较正常喉组织PTEN mRNA表达下降有统计学意义(P<0.05).病理低分化与高分化相比,PTEN mRNA表达差异有统计学意义(P<0.05).结论:PTEN基因表达下降在喉鳞癌演进中起重要作用. 相似文献
110.
M Setoyama Y Katahira T Hamada M Tashiro S Yashiki Y Tanaka H Tozawa S Sonoda 《The Journal of dermatology》1992,19(3):133-139
Adult T-cell leukemia/lymphoma (ATLL) is recognized as a disease etiologically associated with human T lymphotropic virus type-1 (HTLV-1) infection, but, neither viral replication nor specific virus antigen expression have been detected on ATLL cells distributed in organs, including skin. To examine the latent expression of HTLV-1 in the cutaneous lesions of ATLL patients, we cultured the lesional skin tissues in vitro and applied immunofluorescence staining with mouse monoclonal antibodies Lt-4, GIN-14, and F10, which react with p40tax, p19 and gp21, respectively. We recognized HTLV-1 specific antigens on clustered ATLL cells only in the deeper dermis of the skin after 24 hrs cultivation of the lesional skin tissue from an ATLL patient in RPMI-1640 medium supplemented with 20% fetal calf serum. In the electron microscope, we observed HTLV-1 like particles, 80-140 nm in diameter with envelope and core structures, in the same tissue specimen. These findings suggest that HTLV-1 gene products may be expressed in the skin lesions of ATLL patients and involved in the pathogenesis of skin eruptions in cutaneous type ATLLs. To our knowledge, this is the first report that envisages the potency of intracutaneous HTLV-1 expression in vivo. 相似文献