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51.
Six pigs had been immunized with multiple dose of embryonated eggs and an isolated intestinal loop was prepared in each animal. Specific antibodies to Ascaris suum were detected in the soluble protein fraction of washings from the intestinal loops using an indirect fluorescent antibody test. The specific antibodies belonged to the IgA, IgG and IgE classes of immunoglobulins. In contrast, specific antibodies were not detected in the soluble protein fraction from the accumulated fluid from the intestinal loop of one pig. Soluble proteins from the washings of intestinal loops consisted of serum albumin, a large molecular size glycoprotein, and variable amounts of several α-globulins, transferrin, and immunoglobulins. The individual soluble protein solutions were efficiently fractionated using DEAE-cellulose, Sephadex G-200, and Sepharose 6B Chromatographic columns. 相似文献
52.
Endy Chung R.Kent Rhodes Edward J. Miller 《Biochemical and biophysical research communications》1976,71(4):1167-1174
Fractionation of pepsin-solubilized collagens from several human tissues has shown that substantial quantities of collagen-like protein remain in solution under conditions leading to the precipitation of Type I, II, and III collagens. Characterization of the more soluble collagens has led to the isolation of three unique collagenous components each of which exhibit compositional features indicative of their origin from basement membranes. One of these has an apparent molecular weight of 55,000 daltons and appears to originate in endothelial basement membranes. The other two components (A chain and B chain) are somewhat larger than collagen α chains and appear to be derived from the collagen of epithelial and smooth muscle basement membranes, respectively. 相似文献
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Collagen and the acid mucopolysaccharides (AMPS) were studied in the fibular cartilage of brachypod () and normal (+/+) newborn mice. At this age the mutant fibulae are still cartilaginous and are comprised of closely packed chondrocytes, homogenous in size and shape.Brachypod fibular chondrocytes synthesized a normal cartilage-type collagen molecule but at half the normal rate. Incorporation of tryptophan indicated this was related to a depression of general protein synthesis rather than being specific for collagen. Pulse-chase experiments showed that collagen degradation over a 3-day culture period was 15% slower than normal thus accounting for the higher collagen content in mutant fibulae.AMPS synthesis in normals and brachypods was nearly equal; however, in pulse-chase experiments radioactivity could not be chased out of the mutant tissue. The failure of AMPS degradation also accounted for greater than normal quantity of AMPS in the mutant cartilage. Characterization of the AMPS led to the discovery of a small population of unsulfated chondroitin molecules in normal, but not brachypod cartilage. The importance of a coordinated metabolism of matrix products during limb development is discussed. 相似文献
55.
Time-until-death studies were run on cercariae of Schistosoma mansoni in 15 concentrations of zinc (from zinc sulfate) ranging from 57.6 ppm to 1 ppb. A chemically defined water medium was used for the dilution and control medium, and a partially enclosed slide chamber was perfected for the detailed observation of test cercariae. In concentrations of less than 57.6 ppm, zinc was found to have little lethal effect on cercariae during that period in which these larvae were most likely to be infective (0–6 hours) after emergence. Zinc concentration of 1 ppb killed all test cercariae within 46 hours at 21–22°C.At the highest concentration tested, 57.6 ppm zinc immobilized all test organisms within 6 hours at 21–2°C. The average time for 100 percent mortality for the control was 49 hours. The cercaricidal effects of zinc were shown to be insignificant in concentrations that would not be detrimental to other aquatic organisms. 相似文献
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The cinnamic acid 4-hydroxylase of swede root disks is a microsomal enzyme with a specific requirement for NADPH and cinnamic acid. The enzyme is inhib 相似文献
57.
P Rhodes 《BMJ (Clinical research ed.)》1975,2(5969):501-502
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