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81.
V. Nataf M. V. Senat M. Albert L. Bidat P. de Mazancourt J. Roume L. Allard D. Le Tessier Y. Ville J. Selva 《黑龙江环境通报》2002,22(8):675-680
Male phenotype associated with a 45,X karyotype is an infrequent finding. We present a case diagnosed prenatally on amniocentesis performed for maternal age. The male phenotype was associated with a translocation of a distal part of Yp including the pseudoautosomal SHOX gene and SRY gene on the short arm of a chromosome 21. By DNA analysis we could show that the X chromosome was of maternal origin and that the breakpoint was in interval 3 of the Y chromosome. Mechanisms and genetic counselling are discussed based on a review of published cases of 45,X and XX males. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
82.
83.
K. Pilegaard 《Environmental monitoring and assessment》1993,27(3):221-232
The purpose of this investigation was to monitor airborne dipersion of particulates in connection with exploration activities at a niobium-mineralization in the Sarfartoq area, SW Greenland, during the summer of 1989, and to provide a basis for monitoring strategies in later phases of the development of the mining site. During three periods moss bags were exposed at 9 stations close to the outcrop and at 3 background stations, and indigenous lichens and mosses were sampled before and after the exploration work.Analyses of element concentrations showed that the natural enrichment of elements in the indigenous vegetation is restricted to areas immediately at or on the outcrop. The elements found in elevated concentrations were Nb, La, Ce, Th and U.The moss bags and the indigenous monitor organisms showed rises in concentrations of the elements Nb, Ce, Cd, Pb and Zn after the exploration activities during the summer. This shows that some dispersion of dust has occurred in the area. 相似文献
84.
85.
P Joseph S Viswanatha M K Krishnakumari 《Journal of environmental science and health. Part. B》1992,27(3):269-280
The haematotoxicity of technical hexachlorocyclohexane (HCH) (1000 ppm) was investigated in male albino rats fed with diet free of vitamin A or containing vitamin A at 2000 or 10(5) I.U./kg. Assessment of HCH-induced haematotoxicity at the end of the 7 weeks feeding period was done on the basis of haemoglobin content, total count of red blood cells and white blood cells and the differential counts of the white blood cells as well as by parameters such as packed cell volume, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin content, prothrombin time and clotting time. In the rats fed with vitamin A-free diet containing HCH, significant reductions were noticed in the total white blood cells count, clotting time and prothrombin time indicating severe haematotoxicity. Differential count of the white blood cells of these rats revealed a non-significant reduction in the lymphocyte count. The only indication of haematotoxicity caused by hexachlorocyclohexane in the vitamin A supplemented rats was a slight but statistically significant reduction of the total count of white blood cells. These results demonstrate that the haematotoxicity of hexachlorocyclohexane in the rats is enhanced by vitamin A-deficiency and its supplementation particularly in excess but not at hypervitaminotic level is protective against the toxicity. 相似文献
86.
As part of a programme to characterize floating anthropogenic debris in the aquatic environment, the US Environmental Protection Agency (EPA) conducted 18 field surveys in the harbours of major metropolitan cities of the east, west, and Gulf coasts of the United States and the Mid-Atlantic Bight. the surveys were designed to provide information on the types, relative amounts, and distributions of aquatic debris in different geographic regions of the United States. Neuston nets (0.33 mm mesh) were used to collect surface debris during outgoing tides on two or three consecutive days in selected areas of each city. After each net tow, the debris, which ranged in size from small resin pellets to large plastic sheeting pieces, was identified, categorized, and counted. the data are being used to qualitatively characterize aquatic debris in coastal metropolitan areas, to examine potential regional variations, and to tentatively identify potential sources. 相似文献
87.
Progress in Restoration of the Mauritius Kestrel 总被引:1,自引:0,他引:1
In the 1970s, the Mauritius Kestrel ( Falco punctatus ) was the most endangered bird of prey in the world, at one time with only two known pairs surviving in the remnant native forest of the Black River Gorges (ca. 4,000 ha). At the end of the 1991–1992 breeding season, a minimum of 30 nesting pairs and more than 170 individuals were distributed in four separate forested areas, thanks mainly to manipulation of the reproductive potential of the wild pairs, to captive propagation, and to reintroduction (restocking). Since 1984, 139 young have been reared from 618 eggs laid by captive kestrels, and 147 from 265 wild eggs incubated and hatched in the laboratory; 235 young kestrels have been released on Mauritius by hacking and fostering. Adjustments in feeding and nesting habits of kestrels hacked and released outside the Black River Gorges in areas dominated by exotic vegetation and agriculture have allowed these kestrels to survive and reproduce in an array of previously unused habitats. Now that the kestrels have been released from dependence on the remnant and dying native forest, a viable population of more than 100 nesting pairs should be achievable in a few more years. 相似文献
88.
J. Malczewski R. Moreno-Sanchez L.A. Bojorquez-Tapia E. Ongay-Delhumeau 《Journal of Environmental Planning and Management》1997,40(3):349-374
This paper is concerned with developing a model for group decision making under multiple criteria. The multiple criteria group decision making (MCGDM)problem involves a set of feasible land use patterns that are evaluated on the basis of multiple, conflicting and noncommensurate criteria by a group of individuals. The model integrates the Analytic Hierarchy Process (AHP) and an integer mathematical programming method. The former provides a tool for structuring the decision problem and determining land suitability for different socio-economicactivities (the uses of land), the latter is used to identify the land use pattern that maximizes consensus among interest groups. The model is used to analyze environmental conflict over land resource allocation in the Cape Region of Mexico. 相似文献
89.
90.
Bhopal Gas Tragedy was the worst industrial accident in the world where several thousand persons lost their lives. It occurred at the Union Carbide plant located inside the city of Bhopal and close to the railway station, at midnight of December 2-3, 1984 due to the leakage of MIC gas which took the local sleeping and floating population unawares.
This paper describes the experience of a transit passenger who reached the Bhopal Railway Station by train at about the same time when the deadly gas leakage occurred. 相似文献