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T W Teasdale T I S?rensen A J Stunkard 《Human biology; an international record of research》1992,64(1):99-106
In this study we explore the relationships between intelligence test score, educational level, and degree of body fatness. We collected data on intelligence test score, educational level, height, and weight from a sample of 26,274 young Danish men and computed body mass index (weight/height2) as a measure of fatness. Both intelligence test score and educational level had maximum values below the median for body mass index and declined monotonically thereafter. The decline was equal for test score and educational level and above 32 kg/m2 corresponded to almost half a standard deviation. These results are not readily explained by stigmatization of frank obesity, and other mechanisms, possibly genetic, may be responsible. 相似文献
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I. B. Rosenwald 《Cell proliferation》1990,23(5):463-471
Abstract. Lysosomal inhibitors (amino acid methyl esters) and platelet-derived growth factor stimulate resting NIH 3T3 cells to enter the S period. Incubation of cells in medium containing lysosomal inhibitors causes an increase in protein accumulation and does not disrupt lysosomes. The results indicate that proliferative homeostasis depends partially on the metabolic status of the cell and that catabolic processes activated in resting cells negatively influence prereplicative reactions. 相似文献
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Abstract. Haemagglutination activity was studied in last larval instars, pupae and adults of both sexes of the Culex pipiens mosquito complex. In females of Culex pipiens quinquefasciatus Say, an anautogenous member of C. pipiens complex, activity was detected in the homogenate of the head‐thorax complex, gut and remaining abdomen (after removing the gut), before and after sucking water, glucose solution or blood. Similar investigations were made in females of autogenous Culex pipiens molestus Forskal, a member of the same mosquito complex. The results were compared with data obtained for males of these subspecies, plus the larvae and pupae. The results show that haemagglutination activity in adult females depends not on the sucking of blood, but on the age of the females. In newly emerged females, the level of activity was very low, but after 24 h or 48 h of activity was highly enhanced, even in females that had no possibility to suck water or other liquids including blood. Furthermore, in C. p. molestus, the haemagglutination activity does not change in hungry or engorged females, and a high level of activity was found in the gut of last larval instars, a developmental stage that never takes blood. Treatment with methoprene reduces haemagglutination activity in both sexes, but 20‐hydroxycdysone application decreased activity in the gut of females. It is suggested that haemagglutination activity may be regulated indirectly by the endocrine system. The possibility that haemagglutination activity may depend on some aspect of the digestive system that has no direct connection to blood uptake is discussed. In addition, the activity may be important not only for the elimination of infections, but also for the processing of food and the utilization and transport of nutrients. 相似文献
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Omkar G. Mishra S. Srivastava A. K. Gupta S. K. Singh 《Journal of Applied Entomology》2005,129(4):217-220
Abstract: This study investigated prey consumption, egg production, percent progeny loss, reproductive, pre- and post-reproductive periods, reproductive time ratio, reproductive rate and bioconversion efficiency of four aphidophagous ladybirds, viz. Cheilomenes sexmaculata (Fabricius), Coccinella septempunctata Linnaeus, Coccinella transversalis Fabricius and Propylea dissecta (Mulsant) on Dolichos lablab Linnaeus infested with cowpea aphid, Aphis craccivora Koch. C. sexmaculata had the highest bioconversion efficiency, reproductive rate and reproductive time ratio followed in rank order by P. dissecta , C. transversalis and C. septempunctata . This study indicates that C. sexmaculata has a narrow ecological relationship with A. craccivora . The increased allocation of resources to reproduction as indicated through a high reproductive time ratio and high bioconversion efficiency of C. sexmaculata and P. dissecta suggest that they may be better adapted to compete for this prey with larger species like C. transversalis and C. septempunctata . 相似文献