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81.
目的:在大肠杆菌中表达人B组轮状病毒WH-2株VP7蛋白并制备其兔抗血清。方法:根据B组轮状病毒(GBRV)WH-2株vp7基因的全序列设计引物,用PCR的方法扩增得到vp7基因的编码区。将其克隆到原核GST融合表达载体pGEX-KG内,转化大肠杆菌E.coliDH5α,IPTG诱导表达人B组轮状病毒WH-2株VP7蛋白,经SDS-PAGE分离纯化表达的蛋白免疫新西兰兔,制备人B组轮状病毒WH-2株VP7蛋白抗血清。结果:经鉴定确认,vp7基因以正确的方式插入到载体中,此重组表达载体经IPTG诱导后,可表达相对分子量为53.4 kDa的GST-VP7融合蛋白。制备的抗血清经同样诱导表达的表达载体pGEX-KG表达产物吸收后1:500倍稀释后用Western Blot分析,与53.4 kDa的GST-VP7融合蛋白获得特异性显色信号。结论:人B组轮状病毒WH-2株VP7蛋白成功在大肠杆菌中GST融合表达,所表达的蛋白和制备的抗体不但为研究结构与功能提供了物质基础,也为GBRV所引起的疾病预防、诊断和治疗等流行病学研究和临床诊断奠定了基础,具有重要实际应用价值。 相似文献
82.
S. Ohsaki S. Teraoka T. Tojimbara K. Takahasi H. Toma T. Agishi K. Ota 《Transplant international》1992,5(Z1):S100-S103
Prostaglandin E1 (PGE1) was used in renal transplant recipients with living related donors. The drug was given intravenously from day 1 to day 7 after transplantation at a dose of 40 µg/kg twice a day. A total of 45 patients were studied divided into two groups: 25 patients were treated with PGE1 (group B) and the remaining 20 patients did not receive the drug (group A). In group B, 24-h creatinine clearance (Ccr) was 66 ± 12.8 ml/min compared with 40.3 ± 13.4 ml/min in group A on the fifth postoperative day (P < 0.05). Urinary levels of N-acetyl-β-d -glucosaminidase (NAG) and serum levels of platelet factor 4 (PF4) in group B were significantly lower than in group A. On the fourth postoperative day, the urinary excretion of thromboxan B2 (TxB2) in group A was higher than in group B, but not significantly (5.1 ± 3.0 ng/day and 2.8 ± 1.1 ng/day, respectively). Acute rejection occurred in four patients in group B and in 10 patients (40%) in group A. The percentage of Leu2a-positive lymphocytes in group B was higher than in group A. We conclude that postoperative administration of PGE1 improves graft function in kidneys from living related donors. 相似文献
83.
精子洗涤对精液中HBV DNA含量的影响 总被引:8,自引:0,他引:8
目的:检查HBV感染者精液是否存在乙型肝炎病毒(HBV),探讨精子洗涤是否能去除其中的HBV DNA。方法:用实时荧光定量PCR(FQ-PCR)法检测57名血清HBsAg阳性患者精液中HBV DNA,采用Percoll非连续梯度离心及上游法分离其中21份精液,并对洗涤后标本进行HBV DNA检测。结果:62份精液标本中有15份HBV DNA阳性,阳性率为24.19%;21份用于洗涤的精液标本中有,有7份HBV DNA阳性,洗涤后仍有6份标本阳性。结论:部分HBV感染者精液具有传染性,精子洗涤不能完全去除精液中的乙肝病毒。将HBV感染者的精液用于人工授精或体外受精应慎重。 相似文献
84.
用放免法检测乙型慢性活动性肝炎病人的红细胞c3b受体(KBCCR1).结果:病人RBCCR1明显低于献血员(P<0.05);抗-HBs特异性免疫复合物阳性病人RBCCR1明显低于阴性病人(P<0.01),与红细胞C3b受体花环试验检测结果一致。表明乙型慢性活动性肝炎病人RBCCR1数量减少,活性下降。其原因可能是特异性循环免疫复合物占据了RBCCR1空位,使CR1活性下降。 相似文献
85.
人抗HBsAg噬菌体抗体Fab段基因的序列分析及表达 总被引:3,自引:0,他引:3
对已建的噬菌体抗体库分离出来的人抗-HBs克隆进行了序列分析和表达研究,发现4个克隆中3个克隆的重链和轻链完全相同,DNA序列分析表明VH分别属于VH1亚群和Ⅱ亚群,其轻链VL分别属于VλⅡ亚群和VλⅠ亚群。构建了可溶性Fab段表达载体,显示出在细菌中表达的Fab段抗体与HBsAg特异性结合,这说明所筛选出来的噬菌体抗体具有HBdisplay status 相似文献
86.
检测198例各型乙肝患者血小板功能的五个项目:血小板总数、粘附试验、聚集试验、血块退缩、血小板第3因子有效性,发现各期乙肝患者血小板功能的异常有显著性差异(P<0.01).并提示乙肝患者除有血小板数量的改变外,还有质量的改变,因此,全面的血小板功能检测可作为估计乙肝患者肝损害程度的辅助指标. 相似文献
87.
以正常人外周血淋巴细胞的SCE率作为细胞遗传学指标,研究了Na_2SeO_3与AFB_1相互作用对细胞遗传物质的影响。结果表明,一定浓度的Na_2SeO_3(10 ̄(-5)mol)对AFB_1所诱发的SCE有明显的抑制作用,但当浓度达到10 ̄(-2)mol时,细胞增殖受到抑制,到10 ̄(-1)mol时细胞出现毒性现象。提示Na_2SeO_3具有抑变和细胞毒性双相作用。所以在Na_2SeO_3与AFB_1相互作用的SCE实验中应避免Na_2SeO_3的浓度过高而损伤培养的细胞。 相似文献
88.
Apolipoprotein B polymorphism and altered apolipoprotein B concentrations in Congolese blacks 总被引:1,自引:0,他引:1
Henri-Joseph Parra F. Martin F. Monard N. Ngangoué N. Copin J. M. Bard M. Qafli N. Vu Dac P. Duriez J. C. Fruchart 《Clinical genetics》1991,40(4):263-270
The immunoreactivity of apolipoprotein B (apo B) in plasma obtained from 238 unrelated black African male subjects from the People's Republic of Congo was analysed by non-competitive Enzyme Linked-Immunosorbent Assay (ELISA) with monoclonal BIP 45 anti-LDL antibody. The polymorphism detected by BIP 45 monoclonal antibody is identical to the Ag(c,g) polymorphism. Antibody BIP 45 distinguishes three apo B allotypes (immunophenotypes) encoded by the two allelic genes apo B Ag(c) and apo B Ag(g). Because of co-dominant transmission, genotypes may be inferred from allotypes, and it has been shown that BIP 45 binds strongly to the Ag(c) factor and only weakly to the allelic Ag(g) factor. Analysis of the Congolese plasma samples indicated that 67.65% of them bound BIP 45 with low affinity (Ag(c-,g+) genotype), 28.15% with intermediate affinity (Ag(c+,g+) genotype) and 4.20% with high affinity (Ag(c+,g-) genotype). According to the Hardy-Weinberg equilibrium, this corresponds to gene frequencies of 0.817 and 0.183 for the type Ag(g)/Ag(c) alleles, respectively. After adjustment for age and body-mass index, it was found that the Ag(c) allele decreases the apo B level by 9.62 mg/dl and that the Ag(g) allele increases apo B by 0.43 mg/dl. Therefore, as much as 4.30% of the genetic variance for apo B level could be accounted for by the Ag(c,g) gene locus. 相似文献
89.
L. Paczek J. Pazik M. Teschner R. M. Schaefer W. Rowinski J. Szmidt K. Abgarowicz L. Gradowska M. Morzycka-Michalik A. Heidland 《Transplant international》1994,7(S1):311-313
Abstract The major reason for late graft losses is chronic rejection. Recently, a large number of studies have indicated that proteolytic enzymes play an important role as mediators of glomerular injury. The cysteine proteinases cathepsins B and L degrade structural matrix proteins such as type I collagen and laminin. We investigated intraglomerular protease activities in 12 patients after kidney graftectomy because of end-tage renal disease following chronic rejection. A group of 12 patients undergoing nephrectomy because of cancer served as controls using only non-involved parts of the kidney. The activities of cathepsins B and L in homogenates of isolated glomeruli were measured fluorometrically methylcoumarylamidc substrates and related to DNA content. In rejected kidney allografts we observed significantly enhanced intraglomerular cathepsin B activity and cathepsin B + L activity. 相似文献
90.
J. P. De La Cruz S. Cámara M. A. Frutos F. Sánchez De La Cuesta 《European journal of clinical pharmacology》1992,43(3):307-309
Summary The antiproteinuric effect of the antiplatelet agent dipyridamole has been assessed after inhibiton of thromboxane B2 (TxB2) synthesis in 8 patients with confirmed membranous glomerulonephritis.
There were three study periods, each of 30 days, and 45 days apart, namely a washout period, treatment with dipyridamole 300
mg/d, and dipyridamole 225 mg/d plus aspirin 150 mg/d. On Days 1 and 30 of each study period serum and urine creatinine, 24-h
excretion of protein, creatinine clearance, platelet aggregometry on whole blood and serum TxB2 were measured.
Treatment with dipyridamole alone or with aspirin produced significant inhibition of platelet aggregation and a fall in 24-h
protein excretion; the latter amounted to 54% with dipyridamole alone and 56 % with dipyridamole plus aspirin (NS). Dipyridamole
plus aspirin caused an 82 % reduction in serum TxB2. 相似文献