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961.
H. Zhao O. P. Van Diggelen R. Thoomes J. Huumans E. Young T. Mazurczak Dr. W. J. Kleijer 《黑龙江环境通报》1990,10(2):85-91
A new fluorogenic substrate, 4 methylumbelliferylβ-D-6-sulphogalactoside, was used for the assay of galactose-6-sulphate sulphatase activity in chorionic villi, cultured villus cells, and amniocytes. The fluorometric assay is much more convenient than the conventional assay using radiolabelled, sulphated oligosaccharides. Both types of substrate were used in the prenatal diagnosis of three pregnancies at risk for Morquio type A disease using amniocytes. These enzyme tests, as well as electrophoresis of glycosaminoglycans in the amniotic fluid, indicated affected fetuses in two pregnancies and a non-affected fetus in one. 相似文献
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Dr. Claire Julian-Reynier Geneviève Macquart-Moulin Jean-Paul Moatti Yvette Aurran Françoise Chabal Ségolène Aymé 《黑龙江环境通报》1994,14(9):859-864
More than 10 years after a chromosomal anomaly screening programme was set up in France for pregnant women of advanced age, amniocentesis is still a controversial issue. The reasons why eligible women did not utilize the test and whether or not the existence of social welfare coverage determined women's access to prenatal diagnosis were studied. A group of 291 women aged ⩾35 years who recently gave birth to normal liveborns was interviewed by telephone. Among those aged 38 years and over, who automatically qualified for social security coverage, 75 per cent had undergone amniocentesis as opposed to 23 per cent in the 35 to 37-year-old non-covered age group who did not qualify for social security coverage. In both groups, access to amniocentesis was found to depend on the physicians', women's and male partners' attitudes towards prenatal diagnosis and abortion. Among the younger group, the uptake depended mainly on socio-economic factors. Institutional policies should ensure greater equality of access while allowing for individual preferences. 相似文献
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Summary The water qualities of the River Ganga (The Ganges) over a short stretch from Swarupganj to Barrackpore (in West Bengal) have been determined and are compared with the values reported by the National Environmental Engineering Research Institute of India for the periods 1972–74 and 1979–80. The water quality is generally bad, but not at such alarming levels as previously determined by other agencies. Biochemical and chemical oxygen demand (BOD and COD) levels are high but within tolerable limits. Dissolved oxygen (DO) levels are are fairly high, indicating a reasonable self-purifying capability for the River Ganga. However, nutrient loads containing N and P have increased enormously in recent years. 相似文献
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Dr. R. M. L. Niven 《The Environmentalist》1995,15(4):267-271
Recently the possible link between air pollution and asthma has been at the centre of much political, public and media attention. This concern has been fuelled by evidence of increasing respiratory ill health, especially in children, and the search for an explanation has focused upon environmental pollution, particularly emissions from road transport. Paradoxically this concern has not been induced by new findings that address the fundamental question of the importance of current levels of air pollution in the causation, severity and responses in asthma. Asthma is predominantly an allergic disease of the human airways. These airways are known to become inflamed in response to exposure to a host of environmental factors. This paper reviews evidence of a link between pollution and asthma and examines the role of pollution in the expression of asthma. In more than 90 percent of children in the UK with asthma the major allergen is a protein particle secreted by house dust mites and this is likely to be the cause of the disease in most sufferers. However, if air pollution has a role it must be expressed in one of three ways. First, certain pollutants acting together, singly, or with other environmental triggers, may cause changes in airways and cause symptoms in people already suffering from asthma. Secondly, air pollution may be causing the initiation of asthma by a mechanism independent of other factors. Thirdly, exposure to pollutants may act in combination with allergens to initiate the asthmatic tendency. The medical evidence for each of these possible roles will be discussed. It is crucial that answers are forthcoming to these questions in order that effective and timely air pollution control strategies may be introduced.This paper was delivered at the Global Forum '94 Academic Conference. 相似文献
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