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By coupling Anisakis larval hemoglobin with cyanogen bromide-activated Sepharose, a stable and sensitive antigen for the indirect fluorescent antibody test for anisakiasis was prepared. Using this antigen, cross-reaction with other helminth infections was minimized and the test was greatly simplified.Furthermore, the results obtained indicate that this technique may be useful not only in the sero-diagnosis of anisakiasis but may also be applicable to the diagnosis of other helminthic diseases. 相似文献
94.
Tetsuya Tosa Tadashi Sato Takao Mori Yuhsi Matuo Ichiro Chibata 《Biotechnology and bioengineering》1973,15(1):69-84
Various methods were tried for the immobilization of aspartase, and the preparation having the highest activity was obtained when partially purified aspartase from Escherichia coli was entrapped into polyacrylamide gel Iattice. Enzymatic properties of the immobilized aspartase were investigated and compared with those of the native aspartase. With regard to optimum pH, temperature, concentration of Mn++, kinetic constants and heat stability, no marked difference was observed between the native and immobilized aspartases. By employing an enzyme column packed with the immobilized aspartase, conditions for continuous production of L -aspartic acid from ammonium fumarate were investigated. When a solution of 1M ammonium fumarate (pH 8.5, containing 1mM MnCl2) was passed through the aspartase column at the flow rate of SV = 0.08 at 37°C, the highest rate of reaction was attained. From the column effluents, L-aspartic acid was obtained in a good yield. 相似文献
95.
Exchange of Genetic Material between Salmonella Typhimurium and Escherichia Coli K-12 总被引:10,自引:0,他引:10 下载免费PDF全文
Tadashi Miyake 《Genetics》1962,47(8):1043-1052
96.
FINE STRUCTURE OF SPINY SPORES OF STREPTOMYCES 总被引:1,自引:0,他引:1
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ELECTRON MICROSCOPY OF VIRUS-INFECTED YEAST CELLS 总被引:1,自引:0,他引:1
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Serum levels of 7 alpha-hydroxycholesterol and activities of hepatic microsomal cholesterol 7 alpha-hydroxylase in surgical patients were analyzed by capillary gas-liquid chromatography-selected ion monitoring technique using a new internal standard, 5 alpha-cholestane-3 beta, 7 beta-diol. We found that concentrations of 7 alpha-hydroxycholesterol obtained after alkaline hydrolysis were higher than those without alkaline hydrolysis, indicating that a considerable amount of 7 alpha-hydroxycholesterol in human serum is present in esterified form. Esterified 7 alpha-hydroxycholesterol could also be quantitatively hydrolyzed with cholesterol esterase, suggesting that fatty acid is bound at the 3 beta-position of the cholestenediol. The serum levels of esterified and free 7 alpha-hydroxycholesterol in patients with cholelithiasis were 198.0 +/- 90.3 and 48.3 +/- 19.8 pmol/ml (mean +/- SD), respectively, and were similar to those in patients without hepatobiliary diseases. After treatment with chenodeoxycholic acid (300 mg per day) for 7 to 10 days, esterified and free 7 alpha-hydroxycholesterol levels decreased to 64.9 +/- 33.6 and 20.5 +/- 11.1 pmol/ml, respectively. Activity of cholesterol 7 alpha-hydroxylase was also inhibited. Treatment with ursodeoxycholic acid (600 mg per day) for 7 to 10 days had no inhibitory effect on serum 7 alpha-hydroxycholesterol levels and the enzyme activity. In all groups, high correlations were found between the activity of cholesterol 7 alpha-hydroxylase and serum levels of 7 alpha-hydroxycholesterol: free (r = 0.71, n = 38, P less than 0.001); esterified (r = 0.87, n = 38, P less than 0.001); total (r = 0.87, n = 38, P less than 0.001). Esterified and total 7 alpha-hydroxycholesterol was more highly correlated with the enzyme activity than the free form. We conclude that a significant amount of 3 beta-acyl esters of 7 alpha-hydroxycholesterol is present in human serum and that serum levels of esterified and/or total 7 alpha-hydroxycholesterol are likely to reflect the activity of hepatic cholesterol 7 alpha-hydroxylase and thus the amount of primary bile acids synthesized in the liver. 相似文献