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61.
亚急克病人心肌线粒体内膜电子传递链的琥珀酸氧化酶系,琥珀酸脱氢酶和细胞色素氧化酶活性明显低于对照。H~ -ATP酶的活性及其对寡霉素的敏感性都明显下降。ATP能量化后线粒体膜电位的变化也比对照明显降低。膜脂流动性低于对照。亚急克病人心肌线粒体内观察到较多的电子致密无定形物质,经电镜X射线微区等方法分析,认为这些物质不是Ca_3(PO_4)_2,而可能是一种蛋白质凝聚物。此外,心肌线粒体的硒含量远低于对照,而Ca含量明显高于对照。上述结果都反映亚急克病人心肌线粒体明显损伤。根据克山病患者心肌细胞线粒体结构与功能方面呈现的如此广泛与明显的异常,可将克山病称为“心肌线粒体病(Mitochondrial Cardiomyopathy)”。 相似文献
62.
Primary structure of PDC-109, a major protein constituent of bovine seminal plasma 总被引:12,自引:0,他引:12
F.S. Esch N.C. Ling P. Böhlen S.Y. Ying R. Guillemin 《Biochemical and biophysical research communications》1983,113(3):861-867
The two major protein components of bovine seminal plasma, PDC-109 and BSP I, have been purified by gel filtration, partition chromatography and reverse-phase high performance liquid chromatography from an 86% ethanol precipitate of bovine seminal plasma ejaculate. The complete 109-residue amino acid sequence of PDC-109 has been established by automated Edman degradation of the intact peptide as well as its proteolytic digestion and cyanogen bromide cleavage fragments. The 12,774 dalton structure has two structurally similar domains of 38 and 41 amino acids, each containing two disulfide bonds. 相似文献
63.
A service has been developed in Saskatchewan to make available the results of studies of human chromosomes, the material being forwarded to the laboratory by local transport facilities. During the first year of this project chromosome studies were requested for five doubtful cases of trisomy-21 (two were found to be normal) and for 20 definite cases of trisomy-21 in young patients (two had translocations but the parents of both these children had normal karyotypes). Eleven confirmed cases of Turner''s syndrome, two of Klinefelter''s syndrome, and one each of the D and E syndromes were also studied. The largest group for which studies were requested comprised 36 patients with mental retardation; only two abnormal karyotypes were encountered in this group. 相似文献
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66.
Reduced glutathione (GSH) inhibited catalase activity in a dose-dependent manner. DL-dithiothreitol (DL-DTT) and dithioerythritol (DTE) also inhibited catalase activity. The inhibition of catalase by GSH and DL-DTT could be reduced by NADPH. Polyacrilamide gel electrophoresis demonstrated the inhibition was partially reversible. The inhibition of catalase by GSH appeared to be partly due to superoxide radicals, since it was inhibited by active manganese superoxide dismutase, but not by heat-inactivated enzyme. Other chemical species also appear to take part in the inhibition, but they could not be identified. 相似文献
67.
M R Yi M H Shin M H Leem J S Ryu M H Ahn D Y Min 《The Korean journal of parasitology》1990,28(1):25-30
The direct wet mount examination of vaginal secretion, widely applied for the diagnosis of Trichomonas vaginalis infection in woman patients, is rapid and economical, however, the sensitivity of this technique is not so high. In this study enzyme-linked immunosorbent assay (ELISA) was employed for the detection of serum anti-T. vaginalis IgG and IgM antibodies from 30 vaginal trichomoniasis patients and 30 non-infected healthy persons. The results were as follows: 1. Serum ELISA-IgG value was 0.37 +/- 0.134 (Mean +/- S.D.) in vaginal trichomoniasis patients and 0.21 +/- 0.054 in healthy controls (p less than 0.005), and the sensitivity and specificity of ELISA for serum IgG antibody were 70.0% and 96.7%, respectively. 2. Serum ELISA-IgM value was 0.33 +/- 0.177 (Mean +/- S.D.) in vaginal trichomoniasis patients and 0.11 +/- 0.051 in healthy controls (p less than 0.005), and the sensitivity and specificity of ELISA for serum IgM antibody were 70.0% and 96.7%, respectively. 3. The ELISA-IgG values showed a significant correlation with ELISA-IgM values (r = 0.77, p less than 0.005). With above results, it is assumed that ELISA is a reliable method for the diagnosis of T. vaginalis infection and simultaneous measurement of serum IgG and IgM with this technique is recommended. 相似文献
68.
长江中游鱼类寄生棘头虫区系的研究 总被引:13,自引:1,他引:12
经过3年10次调查,剖检湖北省宜都、黄冈两处江段所产72种鱼类,共计766尾。收集棘头虫10种,其中包括2新种和1新组合,即蛇鮈新棘吻虫(新种)Neoechinorhynchus saurogobi sp.nov.,长江丽棘虫(新种)Brentisentis yangtzensis sp.nov.(Illiosontidae),鲤丽棘虫(新组合)B.cyprini comb.nov.。对长江中游鱼类寄生棘头虫区系的特点进行了分析和探讨。 相似文献
69.
Nucleotide sequence and expression of cheF, an essential gene for chemotaxis in Bacillus subtilis. 总被引:4,自引:4,他引:0 下载免费PDF全文
The cheF gene, which is involved in chemotaxis in Bacillus subtilis, has been cloned, expressed, and sequenced. This gene is contained in a 0.7-kilobase PstI DNA fragment that was isolated from a lambda Charon 4A B. subtilis chromosomal DNA library. This fragment was subcloned into the expression vector pSI-1 and shown to complement the cheF mutation both for chemotaxis and for methanol production in response to the addition of attractants. Plasmid-encoded DNA expression in B. subtilis maxicells indicated that a membrane-associated polypeptide of 20-kilodaltons was expressed from this 0.7-kilobase DNA. The nucleotide sequence of this DNA fragment was determined, and an open reading frame capable of encoding a putative 175-amino-acid protein (Mr 20,002) was identified. In an effort to understand the function of the cheF protein, the dosage of the cheF gene product was varied by altering the concentration of IPTG (isopropyl-beta-D-thiogalactopyranoside) during growth. In the presence of high concentrations of IPTG, chemotaxis was inhibited and methanol production was impaired. 相似文献
70.
睾丸间质细胞—研究自体吞噬的一种正常细胞模型 总被引:1,自引:0,他引:1
In the present study, we tried to estimate, in a semiquantitative way, the relative frequency of the autophagic activity in various cell types under physiological condition. The results indicated that the highest activity appeared to be in the Leydig cells of rat testes. Autophagosomes were frequently observed in electron microscope photographs of Leydig cells, which provide a good model to study the autophagocytosis in normal cells. The autophagic process in Leydig cells was observed with the electron microscope in preparations treated to show CMPase activity. The mode of formation of autophagosomes in Leydig cells can be divided into three steps. Step 1, flattened membranous elements expand to enclose a small cytoplasmic territory to form pre-autophagosome. Step 2, The double membrane profile of the pre-autophagosome then completely encloses the cytoplasmic territory to form early autophagosome in which structurally normal organelles are contained. Step 3, the transformation of an early autophagosome into a late one is accompanied by the loss of one of the two delimiting membranes, the partial disintegration of the enclosed content and simultaneous acquisition of acid phosphatase activity. The enzymatic reactivity is acquired following a close association with the lysosomes. The late autophagosome then reaches the cell surface and appear to exocytose their residual content. 相似文献