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61.
An analytical method is described for the simultaneous quantitative determination of tri-n-butyltin and di-n-butyltin compounds in fish. The sample was extracted with 0.5N HCl-methanol, and the methanol solution was extracted with hexane. The extract was purified by gel permeation chromatography and treated with Grignard reagent to yield the methyl derivatives, which were determined by gas chromatography with flame photometric detection operated in the tin mode (610 nm). Recoveries of tri-n-butyltin chloride (Bu3SnCl) and di-n-butyltin dichloride (Bu2SnCl2) spiked to fish at the levels of 0.2 and 1.0 ppm ranged from 80 to 105%. Detection limits were 0.02 micrograms/g for both compounds. Tri-n-butyltin compounds equivalent to Bu3SnCl levels of 0.07-2.0 ppm and di-n-butyltin compounds equivalent to Bu2SnCl2 levels of 0.02-0.11 ppm were found in reared yellowtails, and these values showed good agreement with the results from gas chromatographic-mass spectrometric analysis.  相似文献   
62.
A liquid chromatographic (LC) procedure is described for the determination by dansylation of the following 16 kinds of biogenic amines found in wine: monomethylamine (MM), ethylamine (EM), iso- and n-propylamine (Pr), iso- and n-butylamine (Bu), iso- and n-amylamine (Am), pyrrolidine (PY), 2-phenethylamine (PH), tryptamine (TR), putrescine (PU), cadaverine (CA), histamine (HI), tyramine (TY), and spermidine (SP). The amines in white and red wine were applied to a column of Amberlite CG-50 type I resin (Na-form) after the column had been washed with water and eluted with 1N hydrochloric acid. This eluate was evaporated to dryness under reduced pressure and derivatized with dansyl chloride (DNS). LC separations were performed on Finepak SIL C18S and LiChrosorb RP-8 columns with an acetonitrile-water elution gradient. In the survey of commercial wines by this method, most of the samples were found to contain 12 amines, including iso-Am, CA, PU, TY, and others. The highest levels of these amines were 4.84 micrograms PU/mL in red wine, and 5.11 micrograms iso-Am/mL in white wine. The total levels of amines in red wine were comparatively higher than in white wine.  相似文献   
63.
The amount of heavy metals discharged from daily life was estimated in order to know the origin of the metals contained in the sewage sludge which is produced in the wastewater treatment plant treating only domestic wastewater. The amounts of the metals discharged from our daily life were estimated to be in the range of 0.2 to 0.3 for Cd, 1.6 to 1.9 for Ni, 3.5 to 6.8 for Pb, 0.8 to 1.4 for Cr, 8.2 to 19.3 for Mn 9.4 to 55.8 for Cu, 44.3 to 62.7 for Zn and 111 to 293 for Fe in mg.d–1 per person, Using these data, the cycle of the metals in our daily life was discussed in relation to land application of sewage sludge.  相似文献   
64.
Effects of soybean hull water-soluble hemicellulose (WSHC) on serum immunoglobulin (Ig) concentration and production of NO and IL-1beta from peritoneal macrophages were examined and compared with those of Agaricus blazei in the rat system. WSHC consisted of arabinose, galactose, xylose, glucose, and rhamnose, and the molecular weight was approximately 500000. Rats were ip administrated each sample at a dose of 0.67, 13.4, or 26.9 mg/kg/day for 14 days. The administration of WSHC resulted in significantly higher productions of IgM (p < 0.01 on day 6, p < 0.05 on day 14) and IgG (p < 0.05 on day 6) than those in other groups. When peritoneal macrophages were stimulated with various concentrations of sample (0.67, 13.4, or 26.9 mg/mL), WSHC significantly increased both NO and IL-1beta productions only at the concentration of 13.4 (mg/mL) compared with those of a saline group. These findings demonstrate that WSHC enhances humoral immunity and activation of macrophages, thereby leading to the augmentation of immune responses in rats.  相似文献   
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The course of vesicular stomatitis in cattle was investigated in 2 dairy herds (A and B) located in the southern San Joaquin Valley of California. Cattle were examined and specimens were obtained for virus isolation and for serologic survey for one year after an epizootic in December 1982. All 33 lactating cows selected for study had oral lesions, but only 19 (58%) were drooling or frothing around the mouth. Lesions on feet and teats were not observed. The healing time (longer than has been reported previously) for oral lesions ranged from 34 to 59 days. The mean serum neutralizing antibody titer for all cows tested in both herds 21 days after clinical signs were first observed was greater than 1:512. The mean titer decreased in the first 11 months after the epizootic, but remained greater than 1:128, and then increased during December 1983. Vesicular stomatitis virus/New Jersey strain was not isolated from 239 blood samples, 235 swab specimens of oral cavities, 38 swab specimens of oral epithelium, 206 urine specimens, or 232 fecal specimens collected from cows; however, it was isolated from tongue epithelium of 3 cows at 1, 4, and 21 days after signs of frothing were first noticed. For 20 lactating cows brought into dairy A during the epizootic, a mean time of 8.9 days elapsed between time of entry and appearance of clinical signs of vesicular stomatitis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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