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31.
乙氧基磷酸酯类有机磷农药单克隆抗体的制备与鉴定   总被引:2,自引:0,他引:2  
制备针对乙氧基磷酸酯类有机磷农药的单克隆抗体,以此为基础建立该类农药的快速免疫筛选检测方法.以二乙基磷酸乙酸为通用结构半抗原,分别使之与牛血清白蛋白和鸡卵清蛋白共价偶联,合成免疫原和包被原并对其进行结构鉴定.偶联成功后的免疫原用于免疫Balb/c小鼠.将免疫成功小鼠的脾细胞与小鼠SP2/0骨髓瘤细胞融合,筛选能稳定分泌抗乙氧基磷酸酯类有机磷农药单克隆抗体的杂交瘤细胞株.获得的小鼠腹水用辛酸-硫酸铵法纯化,所得纯化抗体以琼脂双扩散法鉴定其免疫球蛋白类型,间接竞争ELISA方法测定其对半抗原的灵敏度、特异性和亲和性.结果表明,该抗体分泌IgG1亚类的单克隆抗体,且与二乙基磷酸乙酸的亲和性较高(1.4×107 L/mol),所得抗体对毒死蜱、对硫磷、丙溴磷、氧化乐果、除线磷、二嗪农、溴硫磷、辛硫磷、喹硫磷、三唑磷等农药有特异性反应.该检测技术可用于上述农药的快速定性或定量检测.  相似文献   
32.
Xu WD  Gu YD  Xu JG  Tan LJ 《Plastic and reconstructive surgery》2002,110(1):104-9; discussion 110-1
Phrenic nerve transfer has been widely used in treating brachial plexus avulsion injury. However, the present method crosses the thoracic part of the phrenic nerve, and nerve graft is needed, resulting in a long period of regeneration and partly irreversible muscle atrophy. We present our early experience of using video-assisted thoracic surgery to harvest a full length of phrenic nerve for transfer. Fifteen patients (mean age, 28 years) were treated. The thoracic part of the phrenic nerve was freed by means of video-assisted thoracic surgery and taken out of the thoracic cavity, and a full-length phrenic nerve was transferred to the musculocutaneous nerve to recover elbow flexion. The patients were followed. Another 29 patients with long-term follow-up who underwent traditional cervical phrenic nerve to musculocutaneous nerve transfer in our institute between 1994 and 1997 were selected. The period of newborn potential appearing in the biceps and the period for biceps to achieve M3 between two groups were compared. The operation was safe and no complications occurred. The additional length of phrenic nerve was 12.3 +/- 4.5 cm. Eleven patients received sufficient follow-up. Eight patients achieved biceps recovery to M3 (elbow flexion against gravity), and mean time was 198.8 +/- 36.0 days, much earlier than that of the traditional method (p < 0.01). Pulmonary function recovered to the preoperative level 9 months after operation. This new method is safe and minimally invasive. The result of full-length phrenic nerve transfer is much better than that of the traditional method. It obviously shortens the time required for nerve reinnervation, and offers a promising method for patients who have had a long interval from injury to operation and for forearm muscle reconstruction by phrenic nerve transferred to the median nerve or combined with free-muscle transfer.  相似文献   
33.
应用RNAi技术培育抗TMV病毒转基因烟草   总被引:5,自引:0,他引:5  
利用烟草花叶病毒(TMV)外壳蛋白基因构建RNAi干涉载体, 通过叶盘法转化至烟草K326 和龙江911两个栽培品种。对转基因株系的荧光定量PCR分析表明, 不同转基因株系的病毒RNA靶序列都得到一定程度的降解, 抗病性鉴定结果证实, 转基因K326和龙江911两个栽培品种的转基因材料分别有83%和90%转基因株系对TMV呈现免疫级抗性。  相似文献   
34.
NF-E2相关因子2(nuclear erythroid 2-related factor 2,Nrf2)是一种能调节肝脏中大量解毒和抗氧化防御基因表达的重要转录因子.氧化应激与各种形式的肝损伤有密切的关系.Nrf2由亲电体压力或氧化应激激活,并通过结合抗氧化反应元件(antioxidant response element,ARE)诱导其靶基因,从而对细胞产生保护作用.因此,Nrf2通路在肝脏疾病中的作用已被深入研究.多种动物模型研究结果表明,Nrf2通路通过靶基因表达,在对抗病毒性肝炎、药物性肝损伤、酒精性肝病、非酒精性脂肪肝及肝癌方面表现出了不同的生物功能.根据Nrf2及其信号通路在对抗肝损伤中产生保护作用的相关文献,本文综述并讨论了其作为治疗肝损伤的药物作用靶点方面可能的应用前景.  相似文献   
35.
36.
The aim of the current study was to investigate how proinflammatory conditions affect growth and progression of hepatocellular carcinoma. Human hepatoma cell lines were treated with lipopolysaccharide (LPS) or cyclooxygenase-2 inhibitor, Celecoxib, and in vitro proliferation, apoptosis, and cell cycle progression were assessed. This was followed up with in vivo xenograft assays to monitor tumor growth and metastatic progression under different treatment conditions. While LPS induced cell proliferation, Celecoxib induced apoptosis. Flow cytometry analysis demonstrated that S-phase cell count in LPS group was higher than control group (41.9 ± 3.2 vs 30.6 ± 0.1 %, respectively), whereas G0/G1-phase cells were significantly higher in the Celecoxib group in comparison with the control group (69.6 ± 5.0 vs 50.4 ± 1.6 %, respectively) (p < 0.05). Immunoblot analyses showed induction of epidermal growth factor receptor expression and induction and nuclear accumulation of Wnt/β-catenin and p65 in LPS group. Xenograft assays showed that LPS treatment induced comparatively large, rapidly growing tumors (2,702 ± 572 mm3) that metastasized to lungs, whereas Celecoxib treatment alone (1,008 ± 296 mm3) or in combination with LPS (1,303 ± 283 mm3) suppressed tumor growth in comparison to control groups (2,072 ± 456 mm3) (n = 5; p < 0.05). Inflammation can thus promote hepatoma cell proliferation and growth, and enhance the invasion and metastatic ability of hepatocarcinoma cells through inducing tumor angiogenesis, which in turn may be related to the activation of Wnt/β-catenin and EGFR signaling pathways.  相似文献   
37.
This study explored the feasibility of Lactobacillus pentosus as a live vehicle to deliver and express antigen. First of all, L.?pentosus transformed by electroporation with the plasmids pg611-6D (anchored) and pg612-6D (secretory) based on the xylose operon generated the recombinant strains rLppg611-6D and rLppg612-6D, respectively, expressing the D antigenic site of the spike (S) protein of Transmissible gastroenteritis virus (TGEV), for intragastric administration in mice. Secondly, we collected serum, fecal, nasal, ophthalmic, and vaginal samples from pre-immune mice and after the first immunization (on days 7, 14, 21, 28, 35, and 42) that were used to analyze the levels of immunoglobulins G and A against TGEV by using ELISA. In addition, a plaque reduction assay was performed using sera from groups pg611, pg612-6D, pg11-6D, and phosphate-buffered saline (blank control) to analyze TGEV-neutralizing antibody activity in vitro. A statistically significant difference in serum tests between groups demonstrated that rLppg612-6D induced better immunogenicity than rLppg611-6D, making rLppg612-6D the better candidate for oral vaccine. Taken together, L. pentosus possessed the potential to become a novel vector for mucosal vaccine in the future.  相似文献   
38.
The correlation between rs1205, rs2808630 variants of C-reactive protein (CRP) gene and susceptibility of cancer has been assessed previously, but with conflicting results. We adopted odds ratios (ORs) with 95% confidence intervals (CIs), in silico tools and enzyme-linked immunosorbent assay (ELISA) analysis to evaluate this association. Totally, 10,614 cancer subjects and 33,294 controls were involved in the pooled analysis. When all the studies were pooled, no significant correlation was indicated between the two variants and cancer risk. However, in stratification analysis by ethnicity, we found that CRP rs1205 C>T polymorphism was associated with an elevated risk of cancer in Asians (T-allele vs. C-allele, OR = 1.20, 95% CI = 1.06–1.36, pheterogeneity = .226; TT vs. CC, OR = 1.48, 95% CI = 1.14–1.93, pheterogeneity = .089). Similar findings were observed for rs2808630 variant. In silico tools showed that lung adenocarcinoma participants with high CRP expression may have shorter overall survival time than low expression group. ELISA analysis indicated that CRP expression in prostate adenocarcinoma subjects with TT + TC genotypes was statistically higher than in those with CC genotypes. CRP rs1205 C>T and rs2808630 T>C polymorphism may be associated with cancer risk, especially for Asians.  相似文献   
39.
Temporin-1CEa is an antimicrobial peptide isolated from the skin secretions of the Chinese brown frog (Rana chensinensis). We have previously reported the rapid and broad-spectrum anticancer activity of temporin-1CEa in vitro. However, the detailed mechanisms for temporin-1CEa-induced cancer cell death are still weakly understood. In the present study, the mechanisms of temporin-1CEa-induced rapid cytotoxicity on two human breast cancer cell lines, MDA-MB-231 and MCF-7, were investigated. The MTT assay and the LDH leakage assay indicated that one-hour of incubation with temporin-1CEa led to cytotoxicity in a dose-dependent manner. The morphological observation using electronic microscopes suggested that one-hour exposure of temporin-1CEa resulted in profound morphological changes in both MDA-MB-231 and MCF-7 cells. The membrane-disrupting property of temporin-1CEa was further characterized by induction of cell-surface exposure of phosphatidylserine, elevation of plasma membrane permeability and rapid depolarization of transmembrane potential. Moreover, temporin-1CEa evoked intracellular calcium ion and reactive oxygen species (ROS) elevations as well as collapse of mitochondrial membrane potential (Δφm). In summary, the present study indicates that temporin-1CEa triggers rapid cell death in breast cancer cells. This rapid cytotoxic activity might be mediated by both membrane destruction and intracellular calcium mechanism.  相似文献   
40.
From 2011 to 2012, we collected Scutellonema commune from the rhizosphere soil of coconut(cocos nucifera L.) and Scutellonema magniphasma from the rhizosphere soil of Rosa chinensis in Shenyang, China. S. commune was characterized by rounded scutella, which was varied from two annules anterior to the anus and five annules posterior. The lateral field was not areolated at the level of scutella. S. magniphasma was characterized by varying scutellum, about 7.0 μm in diameter, in position from four annules posterior to four annules anterior to the anus, and areolated at the level of the scutellum.  相似文献   
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