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981.
Immunogenicity of fatty acid anilides in rabbits and the pathogenesis of the Spanish toxic oil syndrome 总被引:1,自引:0,他引:1
Fatty acid anilides, the major xenobiotic found in the cooking oils responsible for the Spanish toxic oil syndrome, are immunogenic for rabbits as ascertained by a skin test reaction, the characterization of specific antibodies against anilides and the immunofluorescent detection of 'anilide dependent antigens' in tissue slices from treated animals. 相似文献
982.
gamma-Glutamyltranspeptidase activity and glutathione levels were studied in rat mammary gland during the lactogenic cycle; both increased during mid-lactation. The enzyme's specific activity with several amino acids showed that glutamine and methionine were the best substrates. Maleate decreased the transpeptidation reaction and increased the hydrolytic activity. These results suggest that gamma-glutamyltranspeptidase from the mammary gland is similar to the enzyme described in other tissues in relation to these properties and the physiological role proposed in amino acids transport. 相似文献
983.
给出矩阵与若当标准形相似时所使用可逆矩阵的求法,并借用若当标准形简化计算矩阵多项式和解线性微分方程组。 相似文献
984.
本文通过一个函数的设计 ,来实现对菜单的控制 ,使对于不同的用户使用不同的菜单功能项 ,从而达到控制用户权限的目的 . 相似文献
985.
构建高校发展状态评价体系的思考 总被引:2,自引:0,他引:2
构建具有中国特色的高校发展状态评价体系是高教事业发展的需要,亦是社会的需求.在构建中,应以全面的教育发展观、科学的教育评价观和教育价值观为指导,突出自身发展潜力的挖掘和评价,突出对办学方向、办学效益和效率的评估;以高校改革发展目标为方向、为动力、为绩效,以激励为基本手段.在操作中,应以统计分析法为基础,配合以调查问卷法、综合评价法、单项评价法、比较分析法等,正确处理四个方面的关系,为教育适度超前发展战略的实施提供必要的保障. 相似文献
986.
987.
988.
Gömez-Casado E Martínez-Lasot J Castro MJ Morales P Trápaga J Berciano M Lowy E Arnaiz-Villena A 《Cellular and molecular life sciences : CMLS》1999,56(3-4):356-362
HLA-E and -G genes show a restricted polymorphism encoding for molecules whose variability is limited at the peptide binding
site. Fourteen alleles that give rise to only three productive proteins for HLA-G (*0101, *0103 and *0104) and five alleles
with three different proteins for HLA-E (*0101, *0102 and *0103) have been described. Expression of these molecules is low
and found in many tissues for HLA-E; HLA-G protein is expressed in extravillous trophoblast cells and thymic epithelium. Molecular
studies have shown how HLA-G and HLA-E bind to natural killer (NK) cells immunoglobulin and lectin-type inhibitory receptors.
HLA-E may act as a sentinel of the cell; if classical class I and HLA-G are being expressed, HLA-E molecules may reach the
cell surface and inhibit the lysis by NK cells. Most findings are consistent with the hypothesis that HLA-E and -G proteins
may be tolerogenic molecules at either the T-cell receptor (TcR) (inflammation, graft rejection) or NK level, switching off
cells which usually attack foreign (including foetus) or self (autoimmune) antigens. A low HLA-E and -G polymorphism is observed
in humans, and their allele frequencies are mostly homogeneous in the populations tested so far. Many studies to detect these
alleles are now being performed in isolated populations and also in pregnancy-associated pathologies. In the present paper,
standard and detailed techniques to detect HLA-E and -G DNA polymorphism are reported and discussed.
Received 14 July 1999; received after revision 25 August 1999; accepted 25 August 1999 相似文献
989.
中国软珊瑚化学成分的研究(十六)——一种新的多羟基甾醇Sartortuosterol A的结构测定 总被引:1,自引:1,他引:1
从中国南海软珊瑚Sarcophyton tortuosum中分离到一种新的多羟基甾醇——扭曲肉芝甾醇A(Sartortaosterol A),通过化学反应和四谱法推定其化学结构为24ξ-甲基-5α-胆甾烷-3α,6β,9α-,25-四醇-25-乙酸酯. 相似文献
990.
Induction of protective immunity against experimental infection with malaria using synthetic peptides 总被引:24,自引:0,他引:24
M E Patarroyo P Romero M L Torres P Clavijo A Moreno A Martínez R Rodríguez F Guzman E Cabezas 《Nature》1987,328(6131):629-632
Synthetic peptides are potential vaccine candidates because they may be able to induce high antibody titres and specific cellular immune responses against native proteins and thus the whole invading organism. In a previous study we showed that immunization with molecules of relative molecular mass (Mr) 155,000 (155K) 83K, 55K and 35K, specific for the late schizont and merozoite stages of Plasmodium falciparum, could elicit either partial or total protection in Aotus trivirgatus monkeys experimentally infected with P. falciparum. Here we have chemically synthesized 18 peptides corresponding to different fragments of these proteins to immunize Aotus trivirgatus monkeys. Some peptides gave partial protection from challenge with P. falciparum parasites, but none provided complete protection individually. A combination of three partially protective peptides gave complete or almost complete protection, however, suggesting that this particular combination of peptides is a good candidate for a malaria vaccine. 相似文献