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91.
简要介绍了应用于中华鲟(Acipenser sinensis)的pop-up标志固定方法,包括预埋体的制作、植入及pop-up标志悬挂等技术,并对其应用效果进行了评价。  相似文献   
92.
The P2X7 receptor (P2X7R) has been implicated in the process of multinucleation and cell fusion. We have previously demonstrated that blockade of P2X7Rs on osteoclast precursors using a blocking antibody inhibited multinucleated osteoclast formation in vitro, but that P2X7R KO mice maintain the ability to form multinucleated osteoclasts. This apparent contradiction of the role the P2X7R plays in multinucleation has prompted us to examine the effect of the most commonly used and recently available P2X7R antagonists on osteoclast formation and function. When added to recombinant RANKL and M-CSF human blood monocytes cultures, all but one compound, decreased the formation and function of multinucleated TRAP-positive osteoclasts in a concentration-dependent manner. These data provide further evidence for the role of the P2X7R in the formation of functional human multinucleated osteoclasts and highlight the importance of selection of antagonists for use in long-term experiments.  相似文献   
93.
The applicability of the less specific protease elastase for the identification of membrane and cytosolic proteins has already been demonstrated. MALDI as ionization technique particularly favors the detection of basic and to a lesser extent of weakly acidic peptides, whereas neutral peptides often remain undetected. Moreover, peptides below 700 Da are routinely excluded. In the following study, the advantage of additional information gained from tandem mass tag zero labeled peptides and the resultant increase in sequence coverage was evaluated. Through derivatization with tandem mass tag reagents, peptide measurement within the standard mass range of the MALDI reflector mode is achievable due to the mass increase. Compared to the unlabeled sample, peptides exhibiting relatively low molecular masses, pI values or higher hydrophobicity could be identified.  相似文献   
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95.
Formalin‐fixed paraffin‐embedded (FFPE) tissues are the primary and preferred medium for archiving patients' samples. Here we demonstrate relative quantifications of protein biomarkers in extracts of laser microdissected epithelial cells from FFPE endometrial carcinoma tissues versus those from normal proliferative endometria by means of targeted proteomic analyses using LC–multiple reaction monitoring (MRM) MS with MRM Tags for Relative and Absolute Quantitation (mTRAQ) labeling. Comparable results of differential expressions for pyruvate kinase isoform M2 (PK‐M2) and polymeric Ig receptor were observed between analyses on laser microdissected epithelial cells from FFPE tissues and corresponding homogenates from frozen tissues of the same individuals that had previously been analyzed and reported. We also identified PK‐M2 in the normal proliferative phase of the endometrium. Other biomarkers in addition to PK‐M2 and polymeric Ig receptor were also observed but not consistently and/or were at levels below the threshold for quantification.  相似文献   
96.
人DFF45蛋白多克隆抗体制备及其初步应用   总被引:2,自引:1,他引:1  
目的:表达、纯化带GST标签的DNA裂解因子45(DNA fragmentation factor 45 ,DFF45)融合蛋白并制备多克隆抗体。方法:构建pGEX-5X-1/DFF45原核表达质粒,转化大肠杆菌BL21,用IPTG诱导融合蛋白表达,经纯化后免疫日本大耳白兔得到多克隆抗体并用CNBr-activated Sepharose? 4B进行纯化。用间接ELISA法检测抗体效价,Western blot鉴定抗体特异性,同时用免疫荧光染色鉴定抗体特异性并观察DFF45的细胞定位。进一步检测DFF45在人类几种细胞系的表达差异情况。结果:成功构建原核表达质粒,表达、纯化DFF45蛋白并免疫动物后得到多克隆抗体。间接ELISA法显示抗体效价达1:20 000,Western blot确定抗体具有高度特异性。应用该抗体检测发现DFF45在人类几种细胞系中表达存在差异并观察到其细胞定位。结论:DFF45多克隆抗体的成功制备及其在人类细胞系的差异表达,为进一步研究DFF45基因与肿瘤及其相关疾病的关系奠定了基础。  相似文献   
97.
HIV-1 gp41 prehairpin fusion intermediate (PFI) composed of three N-terminal heptad repeats (NHR) plays a crucial role in viral fusion and entry and represents an attractive target for anti-HIV therapeutics (e.g., enfuvirtide) and vaccines. In present study, we constructed and expressed two recombinant gp41 PFI mimetics, designated N46Fd and N46FdFc. N46Fd consists of N46 (residues 536-581) in gp41 NHR and foldon (Fd), a trimerization motif. N46FdFc is composed of N46Fd fused with human IgG Fc fragment as an immunoenhancer. We immunized mice with N46 peptide, N46Fd and N46FdFc, respectively, and found that only N46FdFc elicited neutralizing antibody response in mice against infection by HIV-1 strains IIIB (clade B, X4), 92US657 (clade B, R5), and 94UG103 (clade A, X4R5). Anti-N46FdFc antibodies inhibited PIE7 binding to PFI, blocked gp41 six-helix bundle formation, and suppressed HIV-1 mediated cell-cell fusion. These findings provide an important clue for developing recombinant gp41 PFI mimetics-based HIV vaccines.  相似文献   
98.
腰椎多节段退变性滑脱的手术治疗   总被引:1,自引:0,他引:1  
目的:研讨腰椎多节段退变性滑脱手术减压和植骨融合方式与疗效的关系。方法:20例腰椎多节段退变性滑脱患者行后路椎弓根螺钉复位内固定后,采用椎管减压、神经根松解,行椎间植骨和后外侧植骨融合术,采用日本整形外科学会(JOA)下腰痛评分标准评价疗效。结果:获得连续随访者18例,随访时间9月~3年,平均24个月,优良率90%。结论:可靠的内固定、复位,神经根松解,椎间植骨融合治疗腰椎多节段退变性滑脱效果满意,充分的神经根松解是手术治疗的关键。  相似文献   
99.
Analysis of gene-trap Ds rice populations in Korea   总被引:1,自引:0,他引:1  
Insertional mutagen-mediated gene tagging populations have been essential resources for analyzing the function of plant genes. In rice, maize transposable elements have been successfully utilized to produce transposant populations. However, many generations and substantial field space are required to obtain a sufficiently sized transposant population. In rice, the japonica and indica subspecies are phenotypically and genetically divergent. Here, callus cultures with seeds carrying Ac and Ds were used to produce 89,700 lines of Dongjin, a japonica cultivar, and 6,200 lines of MGRI079, whose genome is composed of a mixture of the genetic backgrounds of japonica and indica. Of the more than 3,000 lines examined, 67% had Ds elements. Among the Ds-carrying lines, 81% of Dongjin and 63% of MGRI079 contained transposed Ds, with an average of around 2.0 copies. By examining more than 15,000 lines, it was found that 12% expressed the reporter gene GUS during the early-seedling stage. GUS was expressed in root hairs and crown root initials at estimated frequencies of 0.78% and 0.34%, respectively. The 5,271 analyzed Ds loci were found to be randomly distributed over all of the rice chromosomes. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. Sung Han Park, Nam Soo Jun, Chul Min Kim are contributed equally to this paper  相似文献   
100.
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