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The basic protein of central nervous system myelin has been shown to form complexes with acidic lipids in vitro. We measured the interaction of myelin basic protein with several charged and neutral lipids in a biphasic chloroform/methanol/water system and investigated the effect of decreasing the electrical charge of the basic amino groups of the myelin basic protein by acetylation. The modified myelin basic protein, which has an average of eight acetyl residues incorporated, was characterised by gel electrophoresis and circular dichroism. Complexes formed between the acetylated myelin basic protein and acidic lipids exhibited a reduction in the amount of lipids bound, a value that could be correlated with the number of modified amino groups. The significance of these experiments with reference to protein-lipid interaction in the myelin membrane is discussed. 相似文献
43.
Spigelian hernia is very rare. Together with the direct inguinal hernia which emerges between the inferior epigastric artery and the edge of the rectus muscle, it is more frequent. Congenital openings in the aponeurosis of the transverse muscle permit the hernia either above or under the inferior epigastric artery. Due to neglect of this type of hernia and absence of herniation, the diagnosis can be difficult. Complaints are often uncharacteristic. Surgical intervention is indicated. 相似文献
44.
An allergic glomerunephritis was produced in rats by injection of an anti-basement-membrane-serum (IgG-fraction), taken from rabbits which were sensitized against a basement membrane fraction of rat-glomerula. Tissues from heart, liver, brain, lung and inner ear were compared with the well known alterations of the glomerula. Exclusively in stria vascularis and renal glomerula heavy changements of the basement membranes and endothelial cells could be shown by electronmicroscopic examination and by immunohistological methods. 相似文献
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The disintegration of the nuclear envelope has been examined in nuclei and nuclear envelopes isolated from amphibian oocytes from amphibian oocytes and rat liver tissue, using different electron microscope techniques (ultrathin sections and negatively or positively stained spread preparations). Various treatments were studied, including disruption by surface tension forces, very low salt concentrations, and nonionic detergents such as Triton C-100 and Nonidet P-40. The highest local stability of the cylinders of nonmembranous pore complex material is emphasized. As progressive disintegration occurred in the membrane regions, a network of fibrils became apparent which interconnects the pore complexes and is distinguished from the pore complex-associated about 15-20 nm thick, located at the level of the inner nuclear membrane, which is recognized in thin sections to bridge the interpore distances. With all disintegraiton treatments a somewhat higher susceptibility of the outer nuclear membrane is notable, but a selective removal does not take place. Final stages of disintegration are generally characterized by the absence of identifiable, membrane-like structures. Analysis of detergent-treated nuclei and nuclear membrane fractions shows almost complete absence of lipid components but retention bo significant amount of glycoproteins with a typical endomembrane-type carbohydrate pattern. Various alternative interpretations of these observations are discussed. From the present observations and those of Aaronson and Blobel (1,2), we favor the notion that threadlike intrinsic membrane components are stabilized by their attachment to the pore complexes, and perhaps also to peripheral nuclear structures,and constitute a detergent-resistant, interpore skeleton meshwork. 相似文献
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HP Zahradnik F Geisth?vel R Weitzell M Breckwoldt 《Canadian Metallurgical Quarterly》1976,36(9):710-714
The concentrations of prostaglandin F-equivalents were measured in peripheral plasma during labour at a cervical dilatation of 5 cm and at complete dilatation. After purification, extraction and chromatography the PGF-equivalents were measured radioimmunologically. The intraassay variation was 1.5%, the interassay variation 3.5%. The specificity for PGF was 96-98%. Logit/log transformation of the standardcurve yielded a sensitivity of the assay of 120 pg. At cervical dilatation of 5 cm PGF-equivalents varied between 1300 and 3200 pg/ml plasma. At complete dilatation values changed between 1200 and 5400 pg/ml. These fluctuations correlate timedepending to the uterine contractions recorded and may be interpreted as a result of uterine PGF-release. 相似文献
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Multiple myeloma presenting as ascites 总被引:1,自引:0,他引:1
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