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In stressing the social advantages of the familial incest taboo, most explanations of the taboo ignore the fact that it makes marriage the enemy of the family. The stranger intruded by marriage often poses a threat to existing domestic relationships. The Chinese solution to this problem is to circumvent the taboo by adopting female children who are raised as wives for their foster parents' sons. The family choosing this form of marriage sacrifices prestige and dependable affinal ties, but by socializing their own daughters-in-law they preserve domestic harmony. The fact that many Chinese arrange marriages within the family as a means of preserving the family suggests that widely accepted explanations of the incest taboo exaggerate the dangers of incest and ignore the dangers of the taboo.  相似文献   
158.
SYNOPSIS High hydrostatic pressure is known to interfere with mitosis, cytokinesis and synthesis of DNA, RNA and protein. In Tetrahymena, incorporation of phenylalanine and formation of polysomes are known to be pressure-sensitive. Microsomal preparations from Tetrahymena pyriformis GL can incorporate [14C]-phenylalanine into polypeptides. Incorporation was enhanced by addition of supernatant fraction and 14.5 mM Mg++ An energy-generating system and exogenous messenger (poly U) were essential for polypeptide biosynthesis, Microsomes from pressurized cells (14,000 psi for 5 min) incorporated [14C]phenylalanine as efficiently as control microsomes. Microsomal function was not grossly damaged by pressure in a test system containing exogenous messenger, crude microsomal preparation, exogenous energy-generating system and supernatant fraction containing activating enzymes.  相似文献   
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Certainty regarding the degree to which organic molecules exchange oxygen with local water during plant cellulose synthesis (pex) is necessary for cellulose oxygen isotope (δ18Ocell)‐based applications in environmental and ecological studies. However, the currently accepted notion that pex is a constant of ca. 0.42 appears inconsistent with biochemical theory, which predicts that marked variation may be present in pex, in relation to variation in the turnover time (τ) of the carbohydrate pool available for cellulose synthesis. The above prediction was tested in the present study with the analysis of data collected from leaves of Ricinus communis grown in controlled environmental conditions that varied in light intensity and vapour pressure deficit. The results revealed the existence of considerable variation in both pex and τ across plants in the various growth environments. Moreover, despite uncertainties in estimates of the proportion of source water in the synthesis water (px) and of the biochemical fractionation factor (εo), our experiment yielded strong evidence that pex exhibits a significant, positive relationship with τ, consistent with biochemical theory. The observed variation in pex in association with τ has important implications for the interpretation of δ18Ocell data in environmental/ecological studies.  相似文献   
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