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Anorexia Nervosa and Respecting a refusal of life-prolonging Therapy: A Limited Justification 总被引:1,自引:0,他引:1
Heather Draper 《Bioethics》2000,14(2):120-133
People who suffer from eating disorders often have to be treated against their will, perhaps by being detained, perhaps by being forced to eat. In this paper it is argued that whilst forcing compliance is generally acceptable, there may be circumstances under which a sufferer's refusal of consent to treatment should be respected. This argument will hinge upon whether someone in the grip of an eating disorder can actually make competent decisions about their quality of life. If so, then the decision to refuse therapy may be on a par with other decisions to refuse life-prolonging therapy made by sufferers of debilitating chronic, or acute onset terminal illness. In such cases, palliation might justifiably replace aggressive therapy. The argument will also draw heavily on the distinction between competent refusal of therapy and passive euthanasia, and the distinction between incompetent and irrational decisions. Both distinctions will then be applied to decisions to refuse food. The extent to which sufferers from anorexia nervosa can be categorised as either incompetent or irrational will be examined. It is against this background that it will be argued that at least some of those who suffer from eating disorders should have their refusals respected, even if they may die as a result. 相似文献
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Characterization of a transferrin-diphtheria toxin conjugate 总被引:3,自引:0,他引:3
We report here the synthesis and properties of a hybrid toxin prepared by covalently coupling diphtheria toxin to transferrin. The purified material contained two major hybrid protein species and was highly cytotoxic to mouse LMTK- cells in culture, reducing protein synthesis by 50% in 24 h at a concentration of 1 ng/ml. Cytotoxic activity was completely abolished in the presence of exogenous transferrin or anti-transferrin or anti-diphtheria toxin, thus demonstrating that the hybrid toxin was intoxicating cells via their transferrin receptors and that both the diphtheria toxin and transferrin components of the conjugate were necessary for activity. NH4Cl, a drug that elevates the pH within acidic intracellular vesicles, also blocked cytotoxic activity, suggesting that a low intravesicular pH was required for activity. The inhibitory effect of NH4Cl could be abolished by exposing toxin-treated cells to acidic culture medium, further implicating an acid-dependent step in the mechanism of the hybrid toxin action. Studies on the kinetics of intoxication also implied that endocytosis and exposure to a low pH within vesicles were necessary for cytotoxicity. Altogether, the results suggest that the transferrin-diphtheria toxin conjugate binds to transferrin receptors and is internalized into acidic endocytic vesicles. The enzymatic moiety of diphtheria toxin then apparently enters the cytosol in response to the low pH and subsequently arrests protein synthesis. 相似文献
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The protein quality of barley was determined by the measurement of the protein efficiency ratio (PER). Available lysine in the same samples was determined chemically and by microbiological assay, and relationships were obtained between PER and either total or available lysine content.In the PER test, groundnut meal was found to be a suitable protein supplement to barley for the purpose of detecting differences in the protein quality of barley. The method was sufficiently sensitive to detect a reduction in protein quality of one variety as a result of micronization. Available lysine values obtained by the modified Tetrahymena method were significantly correlated (r = 0.99) with PER values; there was no significant correlation between total lysine content and the PER value.The available lysine values measured by the two chemical methods were higher than the Tetrahymena values. The Silcock method gave results better correlated (r = 0.93) with the Tetrahymena values than did the Carpenter method (r = 0.82). The results of chemical methods were not significantly related with PER values, but the methods ranked the barleys in an order similar to that obtained with the PER and Tetrahymena tests. 相似文献
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