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61.
Peter E. Jensen 《Seminars in immunology》1995,7(6)
CD4+ helper T cells recognize short peptides stably associated with class II MHC molecules displayed on the surface of antigen presenting cells. Very little is known about the sequence of events that lead to the generation of these peptides from protein antigens. It is likely that native proteins must partially unfold before they are cleaved by endopeptidases or bind to MHC proteins. For many antigens, the rate-limiting step in unfolding may involve reduction of disulfide bonds. Evidence that disulfide reduction occurs in endocytic compartments is reviewed and potential mechanisms for the reduction of antigen disulfide bonds are proposed. 相似文献
62.
为了探讨中国遗传性高铁血红蛋白血症患者的基因突变类型和建立相应的基因诊断方法,从已发现的1例Ⅰ型患者的外周血白细胞中提取RNA,应用反转录PCR法分析了Cytb5RcDNA的全部编码序列的921bp片段。结果显示:Cytb5RcDNA基因的第57位密码子存在有Arg→Gln(CGG→CAG)的错义突变。针对这一突变,用套式PCR的方法对已有的3个家系共6名患者进行了基因诊断。结果表明其中两个家系的患者均有此位点的突变,5名患者3名为纯合子,2名为杂合子;而另一家系的患者未检测到,推测可能存在有其它突变类型。提示中国人遗传性高铁血红蛋白血症患者致病的分子基础,并建立了相应的基因诊断方法。 相似文献
63.
P. V. Sergeev S. A. Chukaev Yu. A. Korovkina 《Bulletin of experimental biology and medicine》1997,124(2):786-788
Effects of estradiol and testosterone and of the antiandrogens cyproterone acetate, niftolide, and antiestrogen tamoxifen
on the activities of human erythrocyte glutathione peroxidase and glutathione reductase were studiedin vitro. In contrast to hormone preperations, antihormones in high concentrations (10−4−5×10−4 M) modified the enzyme activities. Cyproterone acetate and tamoxifen increased the activity of glutathione reductase, while
tamoxifen stimulated glutathione reductase and inhibited glutathione peroxidase. Niftolide inhibited both enzymes.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 185–187, August, 1997 相似文献
64.
W. Stürmer E. P. Kromer A. J. G. Riegger K. Kochsiek 《Journal of molecular medicine (Berlin, Germany)》1991,69(7):307-312
Summary We examined the effect of a 16 week therapy with the HMG CoA reductase inhibitor lovastatin in 29 patients (mean age 43 years) with primary hypercholesterolemia. All patients had cholesterol levels above 250 mg/dl (mean 348 ±96 mg/dl) inspite of a lipid lowering diet and a therapy with conventional lipid lowering drugs during a three month screening period. After 4 weeks on placebo 20 mg lovastatin was given orally for 4 weeks. If total cholesterol exceeded 200 mg/dl the dose of lovastatin was increased monthly by 20 mg up to the maximal dose of 80mg/day. After 16 weeks lipid values changed compared with the placebo period: total-cholesterol –25%, triglycerides –8.6%, LDL-cholesterol –31%, APO B –25%, HDL-cholesterol +5.8%, APO AI +0.8%, total-cholesterol/HDL-cholesterol –25%. There was a significant improvement of lipid parameters after lovastatin therapy compared with conventional lipid lowering drugs at the end of the screening period. Lovastatin was well tolerated. A small and reversible rise of transaminases and/or creatinine kinase was observed in 6 patients. Basal levels of ACTH in the morning increased significantly during lovastatin therapy within the normal range. This observation was more frequent in females (10/12) than in males (10/ 17).
Abkürzungen HMG Co A 3-Hydroxy-3-Methyl-Glutaryl-Coenzym A - TChol Gesamtcholesterin - LDL low density lipoprotein - HDL high density lipoprotein - TG Triglyceride - APO AI/B Apolipoprotein AI/B - ACTH Adrenocorticotropes Hormon Diese Publikation enthält Ergebnisse des Dissertationsarbeit von Frau Angela Bink. 相似文献
Abkürzungen HMG Co A 3-Hydroxy-3-Methyl-Glutaryl-Coenzym A - TChol Gesamtcholesterin - LDL low density lipoprotein - HDL high density lipoprotein - TG Triglyceride - APO AI/B Apolipoprotein AI/B - ACTH Adrenocorticotropes Hormon Diese Publikation enthält Ergebnisse des Dissertationsarbeit von Frau Angela Bink. 相似文献
65.
从日本血吸虫大陆株成虫分离总RNA,逆转录合成cDNA第一链,根据菲律宾株26kDa谷胱甘肽S-转移酶(GST)的cDNA序列,设计并合成引物,扩增出26kDa的编码区基因,并克隆到pBluescript质粒。初步酶切鉴定后,从两端对插入片段进行核苷酸序列测定。结果与菲律宾株比较,核苷酸同源性为99.8%,仅第582位碱基不同,菲律宾株为A,而大陆株为G。比较从cDNA推导出的氨基酸序列,两者100%相同。测序结果也与曼氏血吸虫进行了比较。 相似文献
66.
67.
V. P. Komissarenko I. S. Chelnakova A. S. Mikosha 《Bulletin of experimental biology and medicine》1978,85(2):152-154
o,p-Dichlorodiphenyldichloroethane (o,p-DDD) and Perthane, when added in a concentration of 312 M to homogenate and cytoplasmic fraction of dog adrenals, activate glutathione reductase. In a concentration of 156 M, o,p-DDD and Perthane do not affect glutathione reductase activity of the dog adrenals. When given in vitro, o,p-DDD and Perthane activate glutathione reductase of the guinea pig adrenals. o,p-DDD has no effect on glutathione reductase activity of the cytoplasmic fraction of dog liver and kidney, thus confirming the high specificity of its effect on the adrenal cortex.Laboratory of Pathophysiology, Institute of Endocrinology and Metabolism, Kiev. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 2, pp. 159–161, February, 1978. 相似文献
68.
Maria Amutan Eini Nyyssönen John Stubbs Maria R. Diaz-Torres Nigel Dunn-Coleman 《Current genetics》1996,29(5):468-473
Aspergillus niger var.awamori contains multiple copies of a transposable element, Vader. This element was detected as a 437-bp insertion in four independently isolated spontaneous mutants of theniaD (nitrate reductase) gene. The Vader element is present in approximately 15 copies in bothA. niger var.awamori andA. niger. A single copy of Vader was detected from only one of the two laboratory strains ofA. nidulans which were also examined. Insertion of the Vader element into theniaD gene ofA. niger var.awamori caused a 2-bp duplication (TA) of the target sequence. The Vader element is flanked by a 44-bp inverted repeat. The genetic stabilities of the inserted Vader elements atniaD were examined by studying reversion frequencies resulting in colonies able to grow on nitrate as a sole nitrogen source. MutantsniaD392 andniaD436 reverted at a frequency of 9x10-3 and 4x10-2, respectively. Two of the mutants,niaD587 andniaD410, reverted at a lower frequency of 6x10-4. 相似文献
69.
Chen M Bennedsen M Zhai L Kharazmi A 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2001,109(12):801-808
A 65 kD membrane-associated NADH-fumarate reductase subunit, which has a molecular weight similar to that of one of the enzyme subunits from bacteria, was purified from Leishmania donovani promastigotes. NADH-fumarate reductase and other mitochondrial enzymatic activities of L. major and L. donovani promastigotes and amastigotes were investigated. The presence of NADH-fumarate reductase was demonstrated in digitonin-permeabilized L. major promastigotes and mitochondria of L. major and L. donovani promastigotes and amastigotes. The activity of solubilized NADH-fumarate reductase was measured in L. major and L. donovani promastigotes. Succinate exhibited a clear concentration-dependent inhibitory effect on fumarate reductase, whereas fumarate also exhibited a clear concentration-dependent inhibitory effect on succinate dehydrogenase. The data indicate that fumarate reductase is an obligatory component of the respiratory chain of the parasite. Since the enzyme is an important component in the intermediate metabolism in the Leishmania parasite and is absent in mammalian cells, it could be a potential target for antileishmanial drugs. 相似文献
70.
Glutathione metabolism in red cell aging 总被引:2,自引:0,他引:2
Normal human red cells were centrifugally separated according to age by discontinuous density gradient of Percoll. Reduced glutathione (GSH), GSH stability and glucose-6-phosphate dehydrogenase (G6PD) activity in fractionated red cells decreased with age, while oxidized glutathione (GSSG) and methemoglobin (MetHb) increased with age. 相似文献