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91.
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   
92.
采用紫外分光光度法测定脱水穿心莲内酯琥珀酸半酯单钾盐血药浓度,并对腹腔单剂量注射给药后家兔体内药代动力学进行了研究。用计算机对血药时间数据进行了曲线拟合。结果表明:该药腹腔注射给药在家兔体内的转运符合二室开模型动力学方程。  相似文献   
93.
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   
94.
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   
95.
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   
96.
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   
97.
In addition to estrogen widely used all over the world for the prevention of postmenopausal osteoporosis, calcitonin and vitamin D derivatives are commonly employed to treat established osteoporosis at higher age in Japan. In order to critically assess the usefulness of vitamin D derivatives and calcitonin alone or in combination on the advancement of vertebral deformity at higher age, 32 osteoporotic patients with vertebral deformity with the mean age of 79 were randomly divided into 4 groups with indistinguishable age and severity of the vertebral deformity. Group 1 served as the control without specific medications for osteoporosis. Group 2 was treated with 10 units elcatonin (eel calcitonin derivative) injected intramuscularly twice a week. Group 3 was given 0.75 to 1.5μg/day 1α (OH) vitamin D3 orally. Group 4 was given a combination of treatments used in Groups 2 and 3. In the lateral X-ray film of the spine taken prior to the test and every 6 months thereafter, the shape of the vertebral body T8 through L4 was monitored by measuring the anterior, central and posterior heights. Decrease of the vertebral height ratio; anterior or middle height/posterior or adjacent intact posterior height, by more than 20% of the original value or from above to below 0.80 both appeared to be inhibited during administration of 1α (OH) vitamin D3. Such effect seems to be augmented by simultaneous administration of elcatonin. Actual decrease of vertebral height ratio values and the per cent fall from the original value significantly less in Groups 3 and 4 than in Group 1. Development of vertebral deformity assessed by the changes of the vertebral height thus appears to decrease during treatment with 1α (OH) vitamin D3 especially together with calcitonin in established osteoporosis.  相似文献   
98.
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   
99.
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   
100.
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   
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