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11.
Mitman G 《Journal of the history of biology》1988,21(2):173-194
Conclusion John Greene has dismissed the evolutionary ethics of Simpson as a case in which science was only a tool, a weapon, in defense of positions that were essentially religious and philosophical.57 This position adopts an amorphous view of science, in which a scientific theory can be construed to support practically any rhetorical position. The relationship between theory and rhetoric, however, is more complex; it is interactive, with the theory and the rhetoric influencing and supporting one another. It is no coincidence that Allee, Emerson, and Simpson all arrived at a biological basis of democracy and a naturalistic ethics during a period when the future of world politics and man's own morality were in question. Allee's commitment to world peace certainly antedated his theory of sociality, just as Simpson's commitment to democracy undoubtedly preceded his evolutionary views.By adopting a particular theory, however, the biologist necessarily imposes constraints on the corresponding rhetoric. Allee and Emerson could not, for example, have stressed the importance of the individual in democracy, given the orientation and framework of their biological research. There were differences among the social philosophies of Allee, Emerson, and Simpson; these differences depended, in part, on the specific evolutionary metaphors to which they subscribed. Allee's ideas with respect to cooperation were distinct from Emerson's, and both men differed strongly from Simpson on the role of the individual in evolution. The Chicago school was united by a conceptual framework that emphasized the population as the unit of selection, and the importance of cooperation in nature. But cooperation could play many roles: as a unifying principle for a theory of sociality, as an integrating mechanism in physiological functionalism, and as a biological source of hope for a society in the grips of a world war. 相似文献
12.
The response of an established line of non-transformed adult rat liver epithelial cells (ARL 15) to thyroid hormone (T3) (3,5,3'-triiodothyronine) was characterized. Exposure of confluent monolayers to 1.10(-8) M T3 for 3 days increased O2 consumption (QO2) between 14-58%, ouabain-sensitive Rb+ uptake 26%, (Na+ + K+)-ATPase activity 32%, alpha-glycerophosphate dehydrogenase activity 103% and cytochrome oxidase activity 208%. The ARL 15 cells, maintained in continuous culture, therefore, exhibit the hallmarks of an authentic physiological response to thyroid hormone. 相似文献
13.
Apolipoprotein(apo) E deficiency is an inherited disease characterized by type III hyperlipoproteinemia and less than 1% normal plasma apoE concentration. The role of apoE in LDL metabolism was investigated by quantitating the metabolism of radiolabeled normal and apoE-deficient LDL in both normal and apoE-deficient subjects. ApoE deficiency resulted in an accumulation of plasma IDL, and a decreased synthesis of LDL consistent with a block in the conversion of IDL to LDL. The LDL isolated from the apoE-deficient patient was similar to normal LDL in hydrated density, size, and composition. However, the apoE-deficient LDL was kinetically abnormal with delayed catabolism in both normal subjects and the apoE-deficient patient. In addition, the catabolism of normal LDL in the apoE-deficient subject was increased. These results were interpreted as indicating that apoE is necessary for the conversion of IDL to LDL and the formation of kinetically normal LDL. The rapid catabolism of normal LDL in the apoE-deficient patient suggests an up-regulation of the hepatic LDL receptor pathway. Based on these results, apoE is proposed to play an important role in the conversion of IDL to LDL, the formation of kinetically normal LDL, and the regulation of LDL receptor function. 相似文献
14.
K J Lackner S B Edge R E Gregg J M Hoeg H B Brewer 《The Journal of biological chemistry》1985,260(2):703-706
Proapolipoprotein (apo-) A-II and several isoforms of apo-A-II including sialylated isoforms were identified in human plasma and thoracic duct lymph. Proapo-A-II secreted by HepG2 cells was identified by a combination of immunoblots and [14C]arginine incorporation. Proapo-A-II which contains 2 arginine residues could be readily differentiated from mature apo-A-II which contains no arginine. The pI of proapo-A-II is 6.79, whereas the pI of the major apo-A-II isoform in plasma and lymph is 4.90. Minor apo-A-II isoforms have pI values of 5.17, 4.68, 4.42, and 4.20, respectively. Sialoisoforms of apo-A-II were identified, which had a higher apparent molecular weight on sodium dodecyl sulfate-gel electrophoresis than the major isoform and disappeared following neuraminidase treatment. The relative quantity of proapo-A-II was relatively constant in lymph very low density lipoproteins, lymph high density lipoproteins, and plasma high density lipoproteins, whereas the sialoforms and the other minor isoforms of apo-A-II were greater in lymph very low density lipoproteins and the lowest in plasma high density lipoproteins. 相似文献
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16.
E. C. Jorgenson 《Journal of nematology》1984,16(2):154-158
Granular and liquid commercial humates, with micronutrients, and a microbial fermentation product were compared in several combinations with nematicides for their effects on cotton lint yield and root-knot nematode suppression. Fumigant nematicides effectively reduced cotton root galling caused by root-knot nematodes, and cotton lint yields increased. Organophosphates and carbamates were not effective. Occasionally, cotton lint yields were increased or maintained with combination treatments o f humates, micronutrients, and a microbial fermentation product, but galling o f cotton roots by root-knot nematodes was usually not reduced by these treatments. 相似文献
17.
Reversible phosphorylation of 3-hydroxy-3-methylglutaryl CoA reductase in Morris hepatomas 总被引:1,自引:0,他引:1
The reversible phosphorylation of microsomal 3-hydroxy-3-methylglutaryl CoA reductase in host liver and hepatoma 5123C has been investigated. The percentage of the total enzyme activity in vivo was similar in the normal liver, host liver and hepatoma 5123C. The inclusion of 30 mM EDTA and 10 mM mevalonic acid in assays of 3-hydroxy-3-methylglutaryl CoA reductase inactivation in vitro eliminated artifacts generated by the presence of mevalonate kinase. Inactivation of 3-hydroxy-3-methylglutaryl CoA reductase from normal liver, host liver and hepatoma occurred at a similar rate with similar half-times. We conclude that phosphorylation/dephosphorylation of 3-hydroxy-3-methylglutaryl CoA reductase occurs in hepatomas and that the lack of dietary cholesterol feedback inhibition in the hepatomas is not a result of a defect in this particular aspect of the reversible phosphorylation system. 相似文献
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19.
Ian Gregg 《BMJ (Clinical research ed.)》1964,1(5375):115-116
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