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Jacqueline Fabia 《CMAJ》1973,109(11):1104-1107,1109
This study is based on a 10% random sample of medical certifications of birth in Quebec in 1970-71 and on additional information obtained from perinatal death certificates and birth registrations. Smoking in pregnancy significantly reduced the average birth weight after 35 weeks of gestation. It increased the risk of perinatal death by 24%. This increase was concentrated in the age groups under 25 and 35 +, in the parity groups 0 and 4 + and among women with less than 12 years of schooling. The proportion of mothers smoking during pregnancy was 43.2% and ranged as high as 62.2% among those under 20 with less than eight years of schooling. These depressingly high percentages imply that new educational approaches aimed particularly at high-risk groups should be developed and evaluated.  相似文献   
125.
Summary The physiological conditions governing growth and sporulation ofSaksenaea vasiformis Saksena, a fungus with outstanding morphological features quite peculiar for Mucorales, were determined. Earlier studies made byTiwari (1955) on a strain of the same species had shown that this fungus is incapable of sporulating on any synthetic medium normally employed for growing fungi.The fungus had been found to have a high tolerance for very low and high pH values. It showed maximum growth at two pH values, one near neutral point, at pH 6, and another at high alkaline pH value, i.e., pH 11. Reason for this behaviour of this fungus has already been discussed. The most suitable temperature for the growth of the fungus was found to be between 30–35° C.Nearly all the carbon, nitrogen and sulphur sources which generally favour growth of fungi were found to support vegetative growth of this fungus as well. However, sporulation in this fungus had peculiar nutritional needs. Only some of the carbon sources, viz., arabinose, rhamnose, sorbose, galactose, lactose and citric acid which supported poor growth, were found to support good or excellent sporulation. But it may be stated that not all carbon sources supporting poor growth could induce sporulation of the organism. Also none of the nitrogen or sulphur sources could induce the fungus to sporulate in presence of glucose as carbon source.  相似文献   
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The contents of fucose, mannose, galactose, glucose, 2-acetamido-2-deoxy-d-glucose and -d-galactose, and sialic acid, when the results were expressed as nmol per mg of membrane dry-weights, were found to be significantly lower in the membranes of old erythrocytes than in the membranes of young ones. No significant difference was found between young and old membranes when the compositions were expressed as residues per one hundred carbohydrate residues, suggesting that a homogeneous decrease of the carbohydrate moieties may occur during aging in vivo.  相似文献   
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Miss S. Seth 《Hydrobiologia》1971,37(2):211-213
Summary Significant variations among aquatic and terrestrial algae (L. arboricola, Oedogonium sp. and V. hamata), in moisture and hydration percentage have been observed. Both percentages proved to be significantly higher in the aquatic forms.  相似文献   
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