ELISA技术在饲料安全检测中的应用

近年来随着兽药在饲料中的使用日益广泛,饲料安全检测工作在畜牧生产中更加重要,具有高选择性、高灵敏度、高分析效率、低成本、低环境污染特点的ELISA技术成为当今饲料安全检测工作中应用日益广泛的测定技术之一．ELISA技术在饲料安全检测中的运用及其试验条件的要求就显得非常重要．     

Diagnostic role of the antibody response to the 38kDa, 16kDa proteins and lipoarabinomannan of mycobacterium tuberculosis

The antibody response to the 38kDa, 16kDa and Lipoarabinomannan (LAM) antigens ofMycobacterium tuberculosis was evaluated using three different ELISAs based on these antigens. The study group included tuberculosis patients (n=52), patients with HIV and TB co-infection (n=10), other chest symptomatics (n=5), HIV infected individuals (n=10), leprosy cases (n=7) and healthy controls (n=75). The results indicate that the 38kDa and LAM based ELISA for IgM/IgG has a low specificity (ranging from 69–85%) and sensitivity (ranging from 55–78%). When three ELISAs are carried out on a single patient the probability of detection of tuberculosis was significantly increased to 95.2% indicating that a single ELISA test is of low sensitivity and that a combination of ELISA’s may be needed to be of any value as a diagnostic test for tuberculosis. Additionally, a western blot assay of the serum antibody response to protein fraction ofM. tuberculosis was analysed in 15 tuberculosis patients and five healthy controls. A multiple antibody response to various M.tuberculosis proteins was observed which varied from patient to patient as compared to controls who showed a single 38–39 kDa protein band positivity. These finding suggest that a western blot assay which determines the antibody response to a set of antigenic components ofM. tuberculosis could be a better serological test for the diagnosis of tuberculosis in our population.     

Binding of circulating autoantibodies in breast cancer to native and peroxynitrite-modified RNA

Peroxynitrite(ONOO) is a powerful oxidant and nitrosative agent and has in vivo existence.The half life of ONOO at physiological pH is less than 1 s.It can react with nucleic acids,proteins,lipoproteins,saccharides,cardiolipin,etc.,and can modify their native structures.Action of ONOO,synthesized in the authors’ laboratory by a rapid quenched flow process,on structural changes of commercially available RNA was studied by ultraviolet(UV),fluorescence,and agarose gel electrophoresis.Compared to native RNA,the ONOO-modified RNA showed hyperchromicity at 260 nm.Furthermore,the ethidium bromide(EtBr) assisted emission intensities of ONOO-modified RNA samples were found to be lower than the emission intensity of native RNA-EtBr complex.Agarose gel electrophoresis of ONOO-modified RNA showed a gradual decrease in band intensities compared to native RNA,an observation clearly due to the poor intercalation of EtBr with ONOO-modified RNA.Native and ONOO-modified RNA samples were used as an antigen to detect autoantibodies in sera of patients with clinically defined breast cancer.Both direct binding and inhibition enzyme-linked immunosorbent assay(ELISA) confirmed the prevalence of native and 0.8 mmol/L ONOO-modified RNA specific autoantibodies in breast cancer patients.Moreover,the progressive retardation in the mobility of immune complexes formed with native or 0.8 mmol/L ONOO-modified RNA and affinity purified immunoglobulin G(IgG) from sera of breast cancer patients supports the findings of the direct binding and inhibition ELISAs.The peroxynitrite treatment to RNA at a higher concentration appears to have damaged or destroyed the typical epitopes on RNA and thus there was a sharp decrease in autoantibodies binding to 1.4 mmol/L ONOO-modified RNA.It may be interpreted that cellular nitrosative stress can modify and confer immunogenicity on RNA molecules.Higher concentrations of nitrogen reactive species can be detrimental to RNA.However,the emergence of native as well as 0.8 mmol/L ONOO-modified RNA as a novel antigen/substrate for autoantibodies in breast cancer patients indicates that,in future,these molecules might find a place on the panel of antigens for early diagnosis of breast cancer.     

ELISA法检测三种类型的类风湿因子

用ELISA法建立了检测IgM、IgG、IgA三种类风湿因子。在类风湿关节炎(RA)中IgM-RF,IgG-RF,IgA-RF的阳性率分别为67.1％,58.6％,42.8％,明显高于其他结缔组织病,且OD值也高。ELISA法检测IgM-RF的阳性率明显高于乳胶凝集法检测的阳性率,但特异性一样为2.3％,但弥补了乳胶凝集法只能检测IgM-RF的不足,尤其是建立了IgG-RF和IgA-RF的检测,对临床诊断有很大帮助,我们还发现IgA-RF和SS有一定关系。     

ICA69基因工程融合抗原的制备

基于基因工程技术 ,用PCR法扩增出编码ICA6 9的cDNA片段 ,直接克隆到pSPORT 1质粒上 ,经DNA序列测定 ,插入到GST融合蛋白表达载体 pGEX 2T ,构成重组质粒 p2T ICA6 9,得到的表达产物GST ICA6 9融合蛋白用间接ELISA法检测其免疫原性 .测序结果表明 ,所获PCR产物已正确重组到PGEX 2T表达型质粒中 .重组质粒在原核细胞中表达的融合蛋白具有免疫原性 ,并能应用于Ⅰ型糖尿病病人血清中抗ICA6 9抗体的检测 .所获得的表达产物为重组ICA6 9融合抗原 ,有助于提高Ⅰ型糖尿病的预报率和确诊率 .     

生态敏感区旅游资源开发的生态与环境适宜度研究——以内蒙古鄂尔多斯市东胜区为例

本文以地处我国农牧交错带生态敏感区的内蒙古鄂尔多斯市为例，从空间角度分析了旅游开发的生态与环境适宜度问题。文章首先对生态敏感区和生态与环境适宜度的概念进行了讨论与界定，然后根据旅游资源开发和旅游活动的影响特点，结合研究区的自然和生态特征，运用TM影像与DEM模型，对研究区地表切割程度、坡度、坡向等进行定量、定性相结合的分析，并运用归一化指数（NDVI）刻画了研究区的植被状况，根据这些指标对研究区进行旅游开发适宜区划分，共划分出3个适宜区和1个次适宜区。在此基础上，就生态与环境适宜度对研究区旅游资源开发与自然环境保护的指导意义进行了讨论:①在旅游资源开发规划中，要认真研究本地区的生态与自然环境特点，以最大限度地不破坏必要的自然过程；②在适宜区域内进行旅游资源开发，也要认真评估生态与环境影响，以最大限度减轻旅游开发对生态与自然环境保护造成的消极影响；③要充分发挥鄂尔多斯市人文文化旅游资源的优势，尽量减少旅游资源开发对自然生态条件的依赖。     

~(14)C-同化物在农垦58A水稻小孢子的分配与花粉败育

长日诱导不育HPGMR植株,随着花粉的发育,~(14)C葡萄糖同化产期分配到幼穗中的比率,从花粉单核早期的37.38％,不断下降到花粉成熟期的4.96％。反之,在短日诱导的可育植株中,则从花粉单核晚期的7.58％,增加到花粉充盈期的40.58％。可以认为,HPGMR花粉发育后期~(14)C-葡萄糖向幼穗运转的障碍和光合同化产物减少,是花粉败育的重要原因,它导致长日下典败花粉的形成。     

Study on the serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) in patients with Helicobacter pylori Infection

Objective: To evaluate the interaction between serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) and Helicobacter pylori (H. pylori) infection in patients with chronic gastritis and peptic ulcer. Methods: The serum levels of sICAM-1 in 205 patients with chronic gastric diseases were detected by ELISA method and the status of H. pylori was determined by histologic examination, RUT, 14C - UBT, and serology. The sera obtained from 18 healthy volunteers served as controls. Results: The serum levels of sICAM-1 were significantly higher in patients with H. pylori positive than those of H. pylori negative (889.43±32.52 ng/ml vs. 747.07±30.45 ng/ml, P<0.05). The serum levels of sICAM-1 in patients with mild, moderate and severe infection of H. pylori were 841.68±72.36 ng/ml, 905.43±37.59 ng/ml and 1012.54±49.34 ng/ml,respectively (P<0.05). The serum levels of sICAM-1 proved to be significantly correlated with the density of H. pylori colonization in gastric mucosa (rs =0.316, P<0.001). The serum levels of sICAM-1 in patients with chronic gastritis and peptic ulcer were significantly higher than those in healthy controls (P<0.05). Conclusions: These results indicated that H. pylori infection up-regulates the expression of sICAM-1.     

南方大口鲶幼鱼死亡敏感期及开口饵料试验

本文报导了南方大口鲶幼鱼的死亡存在一个敏感期．出现于内源性营养阶段进入混合性营养阶段，即孵化后的第4一10天内．幼鱼饲养中，水蚯蚓比枝角类生长要快．     

Lessons learned about access to government information after World War II can be applied after September 11

The cost of unrestricted dissemination of government information to Americans' safety and security has been a topic of heated debate since September 11, 2001. The risks of dissemination seem to have skyrocketed in this age of terrorist attacks. However, the United States faced similar risks after World War II, when the secret of the atom bomb required close protection. Congress can learn from the process that the U.S. government went through to pass the Atomic Energy Act of 1946 [Atomic Energy Act of 1946. Pub. L. No. 79-585, 60 Stat. 755] during a similar time of national stress and fear and work to pass laws regulating the dissemination of information to the public. In the absence of legislative guidance, agencies have been left to restrict information as they think is best, with inconsistent and disastrous results.