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71.
汉滩病毒核壳蛋白(NP)在杆状病毒系统的表达及其免疫原性研究 总被引:11,自引:0,他引:11
应用杆状病毒表达载体成功地表达了汉滩病毒76-118株(HTNV)核壳蛋白,将HTNVS基因插入杆状病毒转染质粒pAcYMIB的多角体基因启动子下游附近,与经Bsu361酶切线性化的杆状病毒(AcVEPA)DNA共同转染S19细胞,经空斑筛选获得了高效表达NP的重组杆状病毒(AcVHanS)。经SDS-PAGE和Western blot证实,表达产物与HTNV毒粒NP分子量均为50KD左右,紫外扫 相似文献
72.
A组轮状病毒SA11VP6基因的克隆和表达 总被引:4,自引:0,他引:4
从SA11VP6基因全序列克隆开始,设计一对两端带有酶切位点的引物,逆转录PCR扩增出VP6全基因CDNA。经酶切后插入PUC19,构建了VP6全基因克隆PRA6。再经酶切后插入痘苗病毒载休质凿PJSA1175中。利用Lipofectin导入TK143细胞,利用TK基因和Lac基因作为重组病毒的筛选标记。表达产物用单克隆抗体ELISA法检测,发现细胞培养上清和细胞裂解液都是阳性。Western b 相似文献
73.
74.
用人工合成的丁型肝炎病毒抗原(HDV-Ag)肽建立了检测抗HDV-IgM抗体的ELISA方法,本法操作简便、快速,重复性好,特异性强,与抗HAV-IgM、抗Hk-IgM、抗HBs-IgM、抗HCV-IgI、抗CMV-IgM、抗RV-IgM、类风湿因子(RF)及抗核抗体(ANA)阳性血清均不起反应,且可被2-巯基乙醇阻断而不起反应。经初步临床应用,31例正常人血清抗HDV-IgM全部阴性,28例慢活肝患者检出率为32.1%(9/28),17例慢迁肝患者血清阳性率为11.8%(2/17)18例肝癌和肝硬化病人血清阳性率为22.2%(4/18)这三组病人与正常对照者相比较均有显著性差异(P<0.001)。此外,抗HDV-IgM阳性血清的ALT值均明显高于正常参考范围,提示在HDV感染过程中,患者肝细胞进一步受损。实验结果证明,抗HDV-IgM是诊断HDV感染的重要指标,对HDV感染早期诊断具有重要价值。 相似文献
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77.
Histological samples and total non-acid glycosphingolipids were prepared from small intestine of human cadavers with the Le(a+b+) and Le(a–b–) nonsecretor phenotypes and contrasted with the more common Lewis phenotypes. Glycolipid fractions were analysed by thin-layer chromatography and tested for Lewis activity with monoclonal antibodies reactive to Lewis epitopes. Paraffin-embedded small intestine sections were also fluorescently immunostained with anti-Lewis antibodies. Unlike the common Lewis positive phenotypes, we were immunochemically able to demonstrate the copresence of large amounts of Lea and Leb glycolipids in the Le(a+b+) sample. In addition we demonstrated increased formation of extended Lewis structures in this phenotype. By immunohistochemistry Lea, Leb and type 1 precursor chain epitopes could be demonstrated in the brush border. These results show that the expression of the Le(a+b+) phenotype at the erythrocyte phenotyping level parallels the small intestinal expression of this phenotype, and the patterns of Lewis antigen expressions are unique to this phenotype. By immunohistochemistry and immunochemistry we also demonstrated the presence of trace amounts of Lewis active glycoconjugates in the small intestine of the Le(a–b–) nonsecretor and Le(a+b–) samples. In the Le(a–b–) nonsecretor Lea and Leb activity was absent and type 1 precursor was present in brush border, while Leb activity was immunohistologically demonstrated in the Golgi apparatus of the deep glands. Trace amounts of both Lea and Leb glycolipids were identified in this sample. In parallel trace Leb activity could also be detected in the glycolipids of the Le(a+b–) sample and could be immunohistologically demonstrated to be fully expressed in occasional cells in the deep glands of the small intestine, a pattern quite dissimilar to that of the Le(a–b–) nonsecretor. The results in this paper show that the expression of Lewis glycoconjugates in the small intestine parallel the expression of Lewis erythrocyte phenotypes. However, inappropriate Lewis activity is also seen in individuals of other phenotypes and the mechanisms by which these Lewis antigens are made appears to be different for different phenotypes.Abbreviations FITC
fluorescein isothiocyanate
- HPLC
high-performance liquid chromatography
- NeuAc
N-acetyl-d-neuraminic acid
- RBC
red blood cell
- TLC
thin-layer chromatography
- TRITC
tetramethyl rhodamine isothiocyanate 相似文献
78.
Red cell Lewis antigens are carried by glycosphingolipids passively absorbed from plasma. Plasma was collected from a spectrum of individuals with normal and unusual Lewis/secretor phenotypes in order to investigate the glycolipid basis for the unusual phenotypes. Samples were obtained from: a Le(a+b–) ABH nonsecretor who secreted Lewis substances; a Le(a+b–) partial secretor; Le(a+b+) partial secretors; Le(a+b+) secretors; and a full range of normal Lewis/secretor phenotypes as controls. The Le(a+b+) samples represented Polynesian, Asian and Réunion Island ethnic backgrounds. Nonacid glycolipids were prepared, separated by thin-layer chromatography, and then immunostained with potent monoclonal antibodies of known specificity. Despite different serological profiles of the Le(a+b–) and Le(a+b+) Polynesian samples, their plasma glycolipid expressions were very similar, with both Lea and Leb co-expressed. The copresence of Lea and Leb in Le(a+b+) samples is in marked contrast to Caucasians with normal Lewis phenotypes, who have predominantly either Lea or Leb. These results suggest that there is a range of the secretor transferases in different individuals, possibly due to different penetrance or to several weak variants. We also show that Lewis epitopes on longer and/or more complex core chains appear to be predominant in the Polynesian Le(a+b+) samples. The formation of these extended glycolipids is compatible with the concept that in the presence of reduced secretor fucosyltransferase activity, increased elongation of the precursor chain occurs, which supports the postulate that fucosylation of the precursor prevents or at least markedly reduces chain elongation.Abbreviations CBA
chromatogram binding assay
- TLC
thin-layer chromatography 相似文献
79.
The anisotropic self-diffusion coefficient of 7Li+ (I = 3/2) counterions has been studied in hydrated, macroscopically oriented Li-(B)DNA fibers at relatively high water contents, corresponding to approximate DNA-DNA helix axis distances of 22–35 Å, using the pulsed field gradient hmr spin-echo method. Self-diffusion coefficients parallel (D∥) and perpendicular (D?) to the DNA helix axis increase with increasing salt content and with increasing DNA-DNA helix axis distance. The observed anisotropy D∥/D? decreases from 1.6 to 1.2 with the DNA-DNA separation increasing from 22 to 35 Å in the salt-free sample. This result can be understood by the obstruction effect caused by the DNA molecules themselves. The values of the Li+ self-diffusion coefficients in the most water-rich system with no added salt (corresponding to an approximate distance of 35 Å between the DNA helix axes) were D∥ ~ 1.15 × 10?10 m2 s?1 and D? ~ 0.98 × 10?10 m2 s?1, compared to 9.14 × 10?10 m2 s?1 for the diffusion of Li+ in an aqueous solution of LiCl (~ 2.1M). The possible occurrence of restriction effects in the DNA fibers have also been studied by determining the self-diffusion coefficient at different effective diffusion times. The self-diffusion coefficient of Li+ in the sample with the largest DNA-DNA helix axis distance seems to be independent of the effective diffusion time, which indicates that the lithium ions are not trapped within impermeable barriers. The possibility of diffusion through permeable barriers has also been investigated, and is discussed. © 1994 John Wiley & Sons, Inc. 相似文献
80.
Experiments were designed to test the hypotheses that ovarian follicular response to superstimulatory treatment initiated during Wave 1 is equivalent to that of Wave 2, and recovery rate and quality of ova embryos derived from follicles of Wave 1 are equivalent to those derived from follicles of Wave 2. In a preliminary experiment (Experiment 1), heifers were given Folltropin-V (20 mg NIH-FSH-P1, im, bid for 5 d) beginning the day after emergence of the first (n=10) or second (n=10) follicular wave of the estrous cycle, equivalent to approximately Day 1 and Day 10, respectively (Day 0=ovulation). Luteolysis was induced with cloprostenol (500 mug im, bid) on the fourth day of treatment. Fewer (P<0.05) ovulations per heifer were induced in the Wave 1 group than in the Wave 2 group (4.6+/-1.0 vs 9.1+/-1.3). However, the interval from wave emergence to initiation of treatment was found, in retrospect, to have been longer (P<0.05) in the Wave 1 group, i.e., treatment was initiated relatively later with respect to wave emergence. Experiment 2 was designed to correct this disparity and to initiate the same treatment protocol on the day of wave emergence rather than the day after (n=21 per Wave group). There was no difference between Wave 1 and Wave 2 groups in the interval from wave emergence to initiation of treatment (0.4+/-0.1 d), the number of ovulations detected by ultrasonography (6.6+/-1.0 vs 8.2+/-1.7), the number of CL detected at slaughter (6.5+/-0.9 vs 8.1+/-1.8), the total number of ova embryos recovered (5.2+/-0.7 vs 5.1+/-0.8), or the number of fertilized embryos collected (2.8+/-0.6 vs 3.0+/-0.6). In addition, there was no difference between groups in the proportion of heifers that ovulated in either experiment; collectively, luteolysis and ovulation was induced in 58 of 60 heifers. The results supported the general hypothesis that follicles and oocytes of the first and second follicular waves are equivalent in the response to superstimulatory treatment. Regardless of which follicular wave, initiation of treatment near the time of wave emergence appears critical for maximal superovulatory response. Because of the consistency in the time of emergence of Wave 1 (day of ovulation) and equivalence in superovulatory response, use of Wave 1 rather than subsequent follicular waves may be more convenient and time-sparing in superovulation programs; the day of estrus (day before ovulation) may be used as a consistent point of reference for the start of treatment. 相似文献