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41.
目的:探讨胞苷酸鸟苷寡脱氧核苷酸(CpG ODN)联合铝佐剂对丙型肝炎病毒(HCV)重组免疫原的体液免疫作用。方法:采用高交叉HCV-HVR1和E1重组蛋白与CpG ODN、铝佐剂组合,免疫BALB/c小鼠后以ELISA、酶联免疫斑点测定、流式细胞术、免疫沉淀等方法检测相关体液免疫指标和免疫血清多抗的交叉反应性。结果:CpG联合铝佐剂激发了最高的特异性抗体滴度;佐剂通过提高抗体分泌细胞数量、增加脾脏中记忆B细胞数量、增加脾淋巴细胞IL-6、IL-10分泌浓度实现体液免疫增效;CpG则能提高免疫效率,联合铝佐剂时显著提高浆细胞数量;12份HCV阳性血清中有10份可与多抗HVR1 IgG发生免疫沉淀。结论:CpG和铝佐剂联合应用具有协同作用,多抗HVR1 IgG具有较好的交叉反应性。  相似文献   
42.

Introduction  

The revised shared epitope (SE) concept in rheumatoid arthritis (RA) is based on the presence (S) or absence (X) of the SE RAA amino acid motif at positions 72 to 74 of the third hypervariable region of the various human leucocyte antigen (HLA)-DRB1 alleles. The purpose of this study was to investigate SE subtypes on the basis of the American College of Rheumatology 1987 revised criteria for the classification of RA in a cohort of South African RA patients (n = 143) and their association with clinical and circulating biomarkers of disease activity (autoantibodies, acute phase reactants and cytokines).  相似文献   
43.
Proteomic identifications hinge on the measurement of both parent and fragment masses and matching these to amino acid sequences via database search engines. The correctness of the identifications is assessed by statistical means. Here we present an experimental approach to test identifications. Chemical modification of all peptides in a sample leads to shifts in masses depending on the chemical properties of each peptide. The identification of a native peptide sequence and its perturbed version with a different parent mass and fragment ion masses provides valuable information. Labeling all peptides using reductive alkylation with formaldehyde is one such perturbation where the ensemble of peptides shifts mass depending on the number of reactive amine groups. Matching covalently perturbed fragmentation patterns from the same underlying peptide sequence increases confidence in the assignments and can salvage low scoring post‐translationally modified peptides. Applying this strategy to bovine alpha‐crystallin, we identify 9 lysine acetylation sites, 4 O‐GlcNAc sites and 13 phosphorylation sites.  相似文献   
44.
目的构建用于呼吸道合胞病毒(respiratory syncytial virus,RSV)体外拯救的RSV基因组全长cDNA克隆,并进行鉴定。方法根据RSV Long株基因组序列设计并合成引物,利用RT-PCR技术分6段扩增RSV LZ01/09基因组序列并构建克隆载体;测序后,利用重叠PCR与酶切连接技术,根据基因组序列选择特异性酶切位点,引入Kpn I、Xma I和Sal I酶切位点,构建成4个亚克隆载体;将亚克隆载体的插入片段连接至经过改造且包含T7启动子、锤头状核酶、多克隆位点、丁肝核酶、T7终止子的p RSV1载体中,构建RSV基因组全长cDNA克隆;对克隆全长cDNA序列进行测定,与亲本RSV LZ01/09基因组进行同源性比对分析,并与RSV实验参比株进行系统进化树分析。结果测序结果显示,RSV LZ 01/09的基因组全长为15 204 bp,与GenBank公布的RSV基因组序列长度相当,将完整的序列提交GenBank,登录号为KY782635;酶切及测序结果显示,用于RSV全长cDNA克隆构建的基本载体p BSKS-MCS(简称p RSV1)与预期相符,RSV全长基因组cDNA克隆质粒(简称转录载体p RSV1-4F)酶切片段大小与预期一致;同源性比对结果显示,全长cDNA序列与亲本RSV LZ01/09基因组序列同源性高达99.83%;系统进化树分析结果显示,其与RSV-A亚型序列同属于一个分支。结论测序及酶切分析结果表明已成功构建RSVLZ01/09基因组全长cDNA克隆,为建立拯救RSV重组病毒的反向遗传学系统平台奠定了基础。  相似文献   
45.
Yi  D; Lee  RT; Longo  P; Boger  ET; Lee  YC; Petri  WA  Jr; Schnaar  RL 《Glycobiology》1998,8(10):1037-1043
Both the Entamoeba histolytica lectin, a virulence factor for the causative agent of amebiasis, and the mammalian hepatic lectin bind to N-acetylgalactosamine (GalNAc) and galactose (Gal) nonreducing termini on oligosaccharides, with preference for GalNAc. Polyvalent GalNAc- derivatized neoglycoproteins have >1000-fold enhanced binding affinity for both lectins (Adler,P., Wood,S.J., Lee,Y.C., Lee,R.T., Petri,W.A.,Jr. and Schnaar,R.L.,1995, J. Biol. Chem ., 270, 5164-5171). Substructural specificity studies revealed that the 3-OH and 4-OH groups of GalNAc were required for binding to both lectins, whereas only the E.histolytica lectin required the 6-OH group. Whereas GalNAc binds with 4-fold lower affinity to the E.histolytica lectin than to the mammalian hepatic lectin, galactosamine and N-benzoyl galactosamine bind with higher affinity to the E. histolytica lectin. Therefore, a synthetic scheme for converting polyamine carriers to poly-N-acyl galactosamine derivatives (linked through the galactosamine primary amino group) was developed to test whether such ligands would bind the E.histolytica lectin with high specificity and high affinity. Contrary to expectations, polyvalent derivatives including GalN6lys5, GalN4desmosine, GalN4StarburstTMdendrimer, and GalN8StarburstTMdendrimer demonstrated highly enhanced binding to the mammalian hepatic lectin but little or no enhancement of binding to the E.histolytica lectin. We propose that the mammalian hepatic lectin binds with greatest affinity to GalNAc "miniclusters," which mimic branched termini of N-linked oligosaccharides, whereas the E.histolytica lectin binds most effectively to "maxiclusters," which may mimic more widely spaced GalNAc residues on intestinal mucins.   相似文献   
46.
High risk populations and HIV-1 infection in China   总被引:1,自引:0,他引:1  
INTRODUCTION HIV has spread to all of China’s 31 provinces, autono- mous regions and municipalities, creating one of the fast- est-growing HIV/AIDS epidemics in the world [1,2]. The HIV/AIDS epidemic in China has gone through three phases: the Entry Phase (1985 -1988), the Spreading Phase (1989-1994) and the Expansion Phase (1995- present). The striking increase of HIV-1 infections over the past few years may herald entry into a new fourth phase that will include much larger nu…  相似文献   
47.
一种新的制备多克隆抗体的方法   总被引:3,自引:0,他引:3  
用亲和色谱纯化的rhEPO作为抗原免疫KM小鼠和Bal b/c小鼠,然后腹腔注射S180细胞或SP2/0细胞。S180细胞可刺激KM小鼠产生腹水,腹水量大,抗体效价高。而直接注射SP2/0细胞既未能使KM小鼠产生腹水,也未能使Bal b/c小鼠产生腹水。实验提供了一种新的简便、快速、经济地制备高效价多克隆抗体的方法。  相似文献   
48.
Thrombosis plays a major role in acute vessel closure both after coronary balloon angioplasty and after stenting. This review will address the role of antiplatelet and anticoagulant therapy in preventing early thrombotic complications after percutaneous coronary intervention. The focus will be on agents that are routinely available and commonly used.  相似文献   
49.

Introduction

Chronic inflammation combined with glucocorticoid treatment and immobilization puts juvenile idiopathic arthritis (JIA) patients at risk of impaired growth and reduced bone mineral density (BMD). Conventional methods for evaluating bone age and BMD are time-consuming or come with additional costs and radiation exposure. In addition, an automated measurement of bone age and BMD is likely to be more consistent than visual evaluation. In this study, we aimed to evaluate the feasibility of an automated method for determination of bone age and (cortical) bone mineral density (cBMD) in severely affected JIA patients. A secondary objective was to describe bone age and cBMD in this specific JIA population eligible for biologic treatment.

Methods

In total, 69 patients with standard hand radiographs at the start of etanercept treatment and of calendar age within the reliability ranges (2.5 to 17 years for boys and 2 to 15 years for girls) were extracted from the Dutch Arthritis and Biologicals in Children register. Radiographs were analyzed using the BoneXpert method, thus automatically determining bone age and cBMD expressed as bone health index (BHI). Agreement between measurements of the left- and right-hand radiographs and a repeated measurement of the left hand were assessed with the intraclass correlation coefficient (ICC). Regression analysis was used to identify variables associated with Z-scores of bone age and BHI.

Results

The BoneXpert method was reliable in the evaluation of radiographs of 67 patients (radiographs of 2 patients were rejected because of poor image quality). Agreement between left- and right-hand radiographs (ICC = 0.838 to 0.996) and repeated measurements (ICC = 0.999 to 1.000) was good. Mean Z-scores of bone age (−0.36, P = 0.051) and BHI (−0.85, P < 0.001) were lower compared to the healthy population. Glucocorticoid use was associated with delayed bone age (0.79 standard deviation (SD), P = 0.028), and male gender was associated with a lower Z-score of BHI (0.65 SD, P = 0.021).

Conclusions

BoneXpert is an easy-to-use method for assessing bone age and cBMD in patients with JIA, provided that radiographs are of reasonable quality and patients’ bone age lies within the age ranges of the program. The population investigated had delayed bone maturation and lower cBMD than healthy children.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-014-0424-1) contains supplementary material, which is available to authorized users.  相似文献   
50.
ABSTRACT. Sensitivity to cooling stress in the last instar larvae of Galleria mellonella was measured as (a) the number of extra larval moults, (b) the number of larvae retaining the ability to secrete silk, and (c) the number showing arrested development. With respect to (a) and (b) there were considerable differences in sensitivity across the day. A relationship was observed between the number of additional larval moults induced by chilling and the ability of prepupal larvae to spin silk: the periods during the 24 h when the most larvae passed through additional larval moults were periods characterized by the smallest number of larvae capable of spinning, and vice versa. These daily changes were apparently partly independent of developmental age. Daily variations in sensitivity also occurred when larvae of the same age were cooled at different times of day. It is suggested that these rhythms in cold-sensitivity are related to a cold-sensitive rhythm in juvenile hormone secretion, or hormone sensitivity in the tissues.  相似文献   
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