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581.
582.
Cyanide (CN) residue levels were determined in samples of extracted honey, comb honey and was cappings at 1 hr, 24 hr, and 48 hr intervals after destroying the bees in honey bee colonies with normal (ca. 8.5 g) and twice normal (ca. 17 g) doses of CyanogasR A-dust. Applications of CyanogasR A-dust, administered by means of a dust pump at normal and twice normal doses, gave an average residue of 0.01 and 0.04 microgram CN/g of extracted honey, 0.01 and 0.02 microgram CN/g of comb honey and 0.04 and 0.06 microgram CN/g of wax cappings, respectively. When the CyanogasR A-dust (ca. 17 g) was placed on a tray and placed on the bottom board of the hive, the average residue levels for extracted honey, comb honey and wax cappings were less than 0.004, 0.01 and 0.02 microgram CN/g, respectively. Random honey samples from beekeepers, who used CyanogasR to destroy bees, had a median level of 0.031 microgram CN/g, whereas honey from a packing plant and other commercial samples contained less than 0.004--0.026, median less than 0.004 microgram CN/g. Based on residue data from this study, the temporary registration for CyanogasR, to kill honey bees after crop removal, was revised to a full registration in May 1977. 相似文献
583.
R. H. Sijmons MD B. Sikkema-Raddatz M. D. Kloosterman J. W. Briet B. De Jong N. J. Leschot 《黑龙江环境通报》1995,15(3):285-290
Chorionic villus sampling (CVS) was performed on a 40-year-old woman at 9 1/2 menstrual weeks because of advanced maternal age. The direct preparation showed 46,XY,dup(10)(q11.2q23.2). CVS long-term culture and fetal tissue revealed a rare additional abnormality: 48,XXXY,dup(10)(q11.2q23.2). This abnormality represented the major cell line (>85 per cent in 691 cells) in an (XY)/XXY/XXXY/(XXXXY) mosaic (all cell lines presumably bearing the dup(10q); the presence of XY and XXXXY cell lines is uncertain). To our knowledge, this is the first report of trisomy 10q11-q23 and of prenatally detected 48,XXXY in chorionic villi. The mosaic could have resulted from early post-zygotic non-disjunctions in a 46,XY,dup(10q) or 47,XXY,dup(10q) zygote. The results from DNA studies of four polymorphisms, mapped to Xp and Xq, support this theory. The literature on prenatally detected cases with sex chromosome tetrasomy and pentasomy and those with additional autosomal abnormalities is reviewed. The reported case underlines the problem of false-negative findings when only direct CVS preparations are karyotyped. 相似文献
584.
Nelson R. Nunnally 《Environmental management》1985,9(5):417-425
Many of the environmental problems associated with channel modifications can be anticipated if known fluvial relationships are considered early in the planning process. Plan modifications or corrective measures can be employed to prevent environmental degradation and improve project performance. The fluvial system is reviewed from a geomorphic perspective. Functional fluvial relationships are described and their use in planning and design of flood channels is demonstrated. 相似文献
585.
586.
Earthworms and soils were collected from 20 diverse sites in Maryland, Pennsylvania, and Virginia, and were analyzed for Pb, Cu, Zn, Cd, Cr, As, and Se. Correlation coefficients relating concentrations of the elements in earthworms to concentrations in soil were low (–0.20<r<+0.57). Species differences and ecological variables contributed to the variability in concentrations of these elements in earthworms. The maximum concentrations of Pb (2100 ppm), Zn (1600 ppm), Cd (23 ppm) and Se (7.6 ppm) detected in earthworms were in the range reported to be toxic to animals fed diets containing these elements; however, even in the absence of any environmental contamination, some species of earthworms may contain high concentrations of Pb, Zn, and Se. Earthworms of the genus Eisenoides, for example, were exceptional in their ability to concentrate Pb. When earthworms are used as indicators of environmental contamination, it is important to identify the species, to report the soil characteristics, and to collect similar earthworms from very similar but uncontaminated soil. 相似文献
587.
Ascoli-Morrete Thaís Bandeira Nelson M. G. Signor Elias Gazola Humberto A. Homrich Isis S. Biondo Rhaíssa Rossato-Grando Luciana G. Zanella Noeli 《Environmental science and pollution research international》2022,29(30):45549-45559
Environmental Science and Pollution Research - The expansion of agricultural activities causes habitat loss and fragmentation and the pollution of natural ecosystems through the intense use of... 相似文献