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101.
102.
We have investigated the ontogeny of MHC class I, class II, CD45, and macrophage antigens in wholemounts of normal human fetal retina at 10–25 weeks gestation (WG) using monoclonal antibodies and immunogold histochemistry. MHC class I antigens were expressed on retinal vascular endothelial cells and provided a useful marker of vessel organization from 14–25 WG. Microglial cells expressed immunoreactivity to MHC class I, class II, and CD45 antigens from 10 WG (pre-vascularization) and macrophage S22 (Mac S22) antigen from 14 WG (post-vascularization), although none of the antigens tested were detected on neuronal or macroglial elements. Microglia expressing MHC, CD45, and macrophage antigens occurred in both ramified and rounded forms with no close correlation being observed between morphology and antigenicity. The numbers of immunoreactive cells labeled with each of the four markers increased steadily throughout gestation in all specimens studied. Equivalent numbers of microglia expressed MHC class I, class II, and CD45 antigens in retinae at similar gestational ages; however, our data indicate that microglia expressing Mac S22 antigen comprise approximately 40% or less of the population of MHC and CD45-immunoreactive cells during development. Topographical analyses suggest that MHC class I, class II, and CD45-positive microglia enter the retina from both the peripheral retinal margin and the optic disc from at least 10 WG; Mac S22-positive cells appear in association with the development of the retinal vasculature and enter the retina via the optic disc after 14 WG. © 1995 Wiley-Liss, Inc. 相似文献
103.
作者采用PCR方法克隆了我国海南省FCC1/HN株P190抗原两个保守区基因,分别定名为P190CRI和P190CRV。基因片段经纯化后连接到pUC18载体中进行DNA序列分析,结果显示:除了P190CRV中有5个碱基变换外,其余序列均与MAD20型序列一致。经序列分析的两个基因片段分别与pGEX-2T载体连接,经双酶切鉴定后转化感受态JM109(DE_3)大肠杆菌进行高效融合表达,并且用Sepharose 4B-谷胱甘肽层析柱进行亲和纯化,结果为:两个插入基因片段均得到高效融合表达,经一步亲和纯化后就取得高纯度的重组蛋白。 相似文献
104.
105.
Three predominant proteins secreted by the human prostate gland 总被引:3,自引:0,他引:3
Analyses of the proteins of azoospermic ejaculates from subjects with defective seminal vesicles demonstrated that three prostatic-secreted proteins were predominant. Prostatic acid phosphatase (PAP), prostate-specific antigen (PSA; or gamma-seminoprotein), and beta-microseminoprotein (beta-MSP; or beta-inhibin), were identified as the three predominant proteins secreted by the normal human prostate gland. Immunohistochemical localization of these proteins, in the epithelium of normal prostatic acini and ducts, with the avidin-biotin complex procedure demonstrated that each PAP-immunoreactive cell was invariably immunoreactive both with PSA-and beta-MSP-monospecific antisera as well. 相似文献
106.
107.
Atopic dermatitis (AD) is today the most common, chronic inflammatory skin disease among children in developed countries. Its cumulative prevalence varies from 20% in northern Europe and the USA to approximately 5% in Mediterranean countries. As a chronic disease it puts a special demand on treatment. There is no curative therapy, but competent guidance on treatment principles can control the disease in most, if not all children. This article summarizes the evidence-based knowledge that relates to the treatment of atopic eczema. It also gives advice and opinions on prophylactic measures as these are the focus of interest from most parents. LEARNING OBJECTIVE: This article should enable you to give advice and guidance to parents of children with AD, including what is necessary for diagnosis, what is of value and importance considering allergies and allergological investigations, allergen exposure, prophylactic measures, diets and indoor environment. Finally, you should be able to explain the diversity of treatment principles for parents. 相似文献
108.
用辣根过氧化物酶标记的癌胚抗原(CEA)抗体,对结肠腺癌患者的手术标本进行了免疫组织化学染色,观察了CEA在肿瘤组织及正常组织细胞中的分布。结果显示,正常结肠组织中,CEA沿粘膜上皮细胞的游离面分布;结肠腺癌细胞则失去极性,CEA除见于细胞游离面,在细胞侧面和基底面也呈阳性反应。提示CEA在结肠细胞表面的分布失去极性可能是腺癌细胞的特点。 相似文献
109.
应用抗增殖细胞核抗原和抑癌基因p53蛋白的单克隆抗体对37例放疗或化疗后的肺癌进行了检测,并与未经术前治疗的肺癌组织进行对照,部分组织进行了超微结构观察。结果发现:(1)放疗或化疗对肺癌组织细胞浆及胞核有不同程度的破坏。(2)放、化疗后组织(除分化型腺癌外)PCNA指数下降明显(P<0.01或P<0.05)。(3)放疗后肺癌组织p53表达率减低,但化疗后变化不明显。 相似文献
110.
Fifty pregnancy alloantisera directed towards HLA-A23 and/or A24 antigens were investigated serologically in titration studies against the three sequenced HLA-A9 specificities, A23 (A*2301), A24 (A*2402) and A2403 (A*2403). The reaction patterns of the antisera fell into five categories which allowed the three HLA-A9 specificities to be easily differentiated. Based on the various titre cytotoxicity scores of the antisera five possible antibody specificities were defined: anti-A23; -A24; -A23/24; -A24/2403 and anti-A23/24/2403. One antiserum crossreacted with HLA-A1 and A24. Inspection of the amino acid sequences of 136 HLA-A, B and C molecules allowed the prediction of five unique epitopes corresponding to these antibody specificities, a possible epitope unique to A2403 and confirmation of a likely epitope shared by A1 and A24. These, together with the previously suggested epitopes HLA-A9/ A2/A28 and A1/A23/A24 together with the presence of Bw4 on the three HLA-A9 antigens suggests that the HLA-A9 family of antigens is characterized by a minimum of nine serologically definable epitopes. 相似文献