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1.
Euthanasia and the active-passive distinction   总被引:1,自引:0,他引:1  
The author examines various claimed differences between active and passive euthanasia and, if there are differences, whether they are morally significant. He refutes arguments based on acting vs. not acting, intention, double effect, cause of death, and natural law theory. Reichenbach proposes that the most helpful distinction is the one between intentional killing (active euthanasia) and appropriate treatment for the dying or terminally ill (passive euthanasia). Significant moral difference, however, rests on the contention that intentional killing is always wrong and that, all else being equal, dying by natural means is intrinsically good, whereas dying by unnatural means is not.  相似文献   

2.
After a general discussion of the need for physicians to concern themselves with questions of human ethics, this paper considers genetics, the population explosion, abortion, curing patients of psychological problems which are perfectly normal (such as masturbation), and behavior modification. The population explosion is the outgrowth of the understandable desire to reduce disease and death. Now births must be reduced immediately or the world will eliminate starvation among infants only to have starvation among adults. The 2nd problem is preventing births. Contraception is not caught up in moral problems but abortion pits 1 set of ethics against another. Here, again, the physician must have a broad world view. The humanist theory holds that procedures that enhance human freedom are both natural and desirable while procedures that suppress it are unnatural and undesirable. This also applies to medical procedures. An understanding of the humanist point of view is important to the physician in his work.  相似文献   

3.
Objective: To contrast relief efforts for the 26 December 2004 tsunami with current global HIV/AIDS relief efforts and analyse possible reasons for the disparity. Methods: Literature review and ethical analysis. Results: Just over 273,000 people died in the tsunami, resulting in relief efforts of more than US$10 bn, which is sufficient to achieve the United Nation’s long‐term recovery plan for South East Asia. In contrast, 14 times more people died from HIV/AIDS in 2004, with UNAIDS predicting a US$8 bn funding gap for HIV/AIDS in developing nations between now and 2007. This disparity raises two important ethical questions. First, what is it that motivates a more empathic response to the victims of the tsunami than to those affected by HIV/AIDS? Second, is there a morally relevant difference between the two tragedies that justifies the difference in the international response? The principle of justice requires that two cases similarly situated be treated similarly. For the difference in the international response to the tsunami and HIV/AIDS to be justified, the tragedies have to be shown to be dissimilar in some relevant respect. Are the tragedies of the tsunami disaster and the HIV/AIDS pandemic sufficiently different, in relevant respects, to justify the difference in scope of the response by the international community? Conclusion: We detected no morally relevant distinction between the tsunami and the HIV/AIDS pandemic that justifies the disparity. Therefore, we must conclude that the international response to HIV/AIDS violates the fundamental principles of justice and fairness.  相似文献   

4.
Murphy TF 《Bioethics》1991,5(2):123-138
... Both the past and present have seen a number of methods being used to extinguish homoerotic desire and behavior and to inaugurate heteroeroticism in their place, methods I will here call conversion therapies... The typical defense of such therapy holds that even if homoeroticism is not necessarily a disease or evil, neither is it a universal good... Conversion therapy is morally defensible, on such a view, because some people suffer from the perceived consequences of homoerotic orientations despite the freedom and toleration extended to gay men and lesbians in certain areas... Against the view that conversion therapy is morally defensible as a matter of personal preference, I here argue that such therapy is morally suspect and should be resisted for a number of reasons....  相似文献   

5.
The broad field of cognitive ethology, in which internal mental states are inferred from the behavior they explain, is receiving increased attention nowadays from diverse scientists and philosophers. The nature of the results and how they are presented greatly influence how humans assess their place in the natural world and how they view other animals. The attribution of consciousness and intelligence to other animals suggests that they have moral rights. The results of comparative cognitive ethological analyses and how they are presented may play a large role in defining the domain of morally permissible research, and in the development of research strategies including decisions on feeding and housing, treatment, handling, and what happens to animal subjects when the research is completed. Scientists and philosophers interested in the evolution of behavior and mental continuity can have a significant impact on how others view the world.  相似文献   

6.
In this study, we investigated the host choice of naïve Amphiprion ocellaris, a specialist, at two different stages of development (newly settling juveniles and post-settlement juveniles). The fish were exposed to their natural and unnatural host species in the laboratory and their fitness was assessed in terms of activity and growth rate. Newly settling juveniles exhibited little host preference, while post-settlement juveniles immediately associated with their most common host in the wild. The analysis of fish activity confirmed that A. ocellaris is diurnal; they are most active in the morning, less at midday and barely move at night. The average travelling distance of juveniles was shorter in the groups living with their natural host, increasing in the groups living with an unnatural host and was highest in groups that did not become associated with any other unnatural host species. Post-settlement juveniles living with the natural host species grew better than those living with unnatural hosts or without anemone contact. These results suggest that the welfare of A. ocellaris in captivity will be optimized by keeping them with their natural anemone host species, although more generalist Amphiprion species may survive in association with other hosts.  相似文献   

7.
Environmental philosophers spend considerable time drawing the divide between humans and the rest of nature. Some argue that humans and our actions are unnatural. Others allow that humans are natural, but maintain that humans are nevertheless distinct. The motivation for distinguishing humans from the rest of nature is the desire to determine what aspects of the environment should be preserved. The standard view is that we should preserve those aspects of the environment outside of humans and our influence. This paper examines the standard view by asking two questions. First, are the suggested grounds for distinguishing humans from the rest of the environment viable? Second, is such a distinction even needed for determining what to preserve? The paper concludes that debates over whether humans are natural and whether humans are unique are unhelpful when deciding what to preserve.  相似文献   

8.
E W Miles 《Biochemistry》1987,26(2):597-603
Tryptophan synthase is a versatile enzyme that catalyzes a wide variety of pyridoxal phosphate dependent reactions that are also catalyzed in model systems. These include beta-replacement, beta-elimination, racemization, and transamination reactions. We now show that the apo-alpha 2 beta 2 complex of tryptophan synthase will bind two unnatural substrates, pyridoxamine phosphate and indole-3-pyruvic acid, and will convert them by a single-turnover, half-transamination reaction to pyridoxal phosphate and L-tryptophan, the natural coenzyme and a natural product, respectively. This enzyme-catalyzed reaction is more rapid and more stereospecific than an analogous model reaction. The pro-S 4'-methylene proton of pyridoxamine phosphate is removed during the reaction, and the product is primarily L-tryptophan. We conclude that pyridoxal phosphate enzymes may be able to catalyze some unnatural reactions involving bound reactants and bound coenzyme since the coenzyme itself has the intrinsic ability to promote a variety of reactions.  相似文献   

9.
Analogs of the decapeptide, gonadotropin-releasing hormone (GnRH), used in the treatment of hormone-dependent tumors, contain numerous unnatural amino acids, giving rise to many adverse effects. lGnRH-III, a natural isoform of GnRH isolated from the sea lamprey, is a weak agonist of GnRH in the pituitary, but inhibits the growth of human cancer cells in micromolar concentrations. As lGnRH-III is not a natural ligand in humans, it is possible that a more potent peptide, also containing only natural amino acids, can be synthesized. A positional scanning peptide library, focused on the variable region of the GnRH family of peptides, residues 5-8, was synthesized. The synthesized peptides were analyzed in competitive binding experiments and six new analogs were designed on the basis of the results. Their biological activities were evaluated in cell growth experiments. The only natural sequence selected was chicken GnRH-II. The synthetic library did not yield a more potent peptide than lGnRH-III.  相似文献   

10.
Context plays an important role in a discriminator's ability to make appropriate recognition decisions, such as accepting what is acceptable and rejecting what is not acceptable. Previously it was shown that in both honey bees and stingless bees, discriminating workers (guards) make more errors towards conspecific non‐nestmates when the guards are removed from the natural hive entrance. However, it may be that guards, in addition to making incorrect recognition decisions, also may adopt non‐guarding behaviours. Here, we tested honey bee guards in two contexts (natural versus unnatural) against five types of introduced arthropods (conspecific nestmates and non‐nestmates; allospecific wasps, beetles and woodlice), which should be rejected without error. We scored a guard's response as accept, reject, avoid and ignore. Total errors significantly increased from natural to unnatural contexts. Specifically, guards were significantly more likely to make an acceptance error, guarding and accepting both conspecific and allospecific non‐nestmates, in the unnatural context. Importantly, guards were significantly more likely to adopt a non‐guarding behaviour in the unnatural context, which usually involved ignoring or avoiding, where a guard makes contact but then immediately retreats, the introduced arthropod. Overall, these data demonstrate the context is important. Removing a guard from the home that it protects elicits either incorrect discrimination or, additionally, a complete lack of discriminator behaviour altogether.  相似文献   

11.
从自然选择和性选择角度分析,同性性行为的存在是一个进化悖论,其成因和意义是当今进化生物学研究的重要科学问题。本文综述了昆虫同性性行为的发生、进化意义和遗传基础等方面的研究进展,分析了研究中存在的问题,并展望了未来的研究方向,以期为昆虫同性性行为的进一步研究提供参考。同时,希望本文能引起更多科学工作者关注昆虫同性性行为,并积极投身到此项研究中来,为该研究领域的发展做出贡献。  相似文献   

12.
13.
The introduction of non‐natural modules could provide unprecedented control over folding/unfolding behavior, conformational stability, and biological function of proteins. Success requires the interrogation of candidate modules in natural contexts. Here, expressed protein ligation is used to replace a reverse turn in bovine pancreatic ribonuclease (RNase A) with a synthetic β‐dipeptide: β2‐homoalanine–β3‐homoalanine. This segment is known to adopt an unnatural reverse‐turn conformation that contains a 10‐membered ring hydrogen bond, but one with a donor–acceptor pattern opposite to that in the 10‐membered rings of natural reverse turns. The RNase A variant has intact enzymatic activity, but unfolds more quickly and has diminished conformational stability relative to native RNase A. These data indicate that hydrogen‐bonding pattern merits careful consideration in the selection of beneficial reverse‐turn surrogates.  相似文献   

14.
Synthesis of both enantiomers of methyl 4,5-didehydrojasmonate (1, Delta(4,5)-MJA; >99.8% ee), a constituent of jasmin absolute, established the absolute configuration of the natural product, and their odor quality was evaluated. The fragrance of the natural (3S,7R)-enantiomer (a fresh natural, sweet floral fruity odor, reminiscent of Jasmin and Ylang Ylang flower, more intensive and tenacious) was superior to that of the unnatural (3R,7S)-enantiomer (a floral green odor with slight metallic green aspect, less intensive than the natural form) and the racemate (green-floral note, having weak and less volume than methyl jasmonate). Odor difference between natural and unnatural enantiomers of methyl jasmonate (2) is also reported.  相似文献   

15.
Raki? has serious misgivings about Wiseman's inability to frame ethical issues in the context of transcending existing realities (the ‘is’) with the aim of achieving what we believe is morally right (the ‘ought’). This inability to think beyond the present is misguided in ethics. He also criticizes Wiseman for making the unimaginative and unsubstantiated assumption that moral bioenhancement (MBE) technologies have reached their zenith already. Raki? argues that MBE will become more effective in the time to come, that it ought to be optional for every free individual, and that it should be directed at enhancing our motivation to act in line with how we believe we ought to act. He concedes however that the enhancement of our motivation to act morally can only be effective in a limited number of morally unambiguous cases. In response, Wiseman argues that Raki?'s reflections epitomize a way of articulating MBE that is unhelpful, misguidedly optimistic, and missing the most important things needing discussion. Such reflections are based on inappropriate metaphors, a too future‐oriented view detached from basic realities, and a false sense of what is possible on the global level should MBE be applied. Such ways of thinking about MBE are misguided from the outset, and indicative of the enthusiasm for a discourse in need of realignment. This should take the form of a more modest, synergistic outlook acutely aware of the inexorable limitations imposed on MBE by the internal complexity of moral goods, human agents, and the contexts in which moral action occurs.  相似文献   

16.
The binding of the natural and unnatural diastereoisomers 25-hydroxyvitamin D3-26,23-lactone and 1,25 dihydroxyvitamin D3-26,23-lactone to the vitamin D-binding protein (DBP) and 1,25 dihydroxyvitamin D3 [1,25(OH)2D3] chick intestinal receptor have been investigated. Also, the biological activities, under in vivo conditions, of these compounds, in terms of intestinal calcium absorption (ICA) and bone calcium mobilization (BCM), in the chick are reported. The presence of the lactone ring in the C23-C26 position of the seco-steroid side chain increased two to three times the ability of both 25(OH)D3 and 1,25(OH)2D3 to displace 25(OH)[3H]D3 from the D-binding protein; however, the DBP could not distinguish between the various diastereoisomers. In contrast, the unnatural form (23R,25S) of the 25-hydroxy-lactone was found to be 10-fold more potent than the natural form, and the unnatural (23R,25S)1,25(OH)2D3-26,23-lactone three times more potent than the natural 1,25-dihydroxy-lactone in displacing 1,25(OH)2[3H]D3 from its intestinal receptor. While studying the biological activity of these lactone compounds, it was found that the natural form of the 25-hydroxy-lactone increased the intestinal calcium absorption 48 h after injection (16.25 nmol), while bone calcium mobilization was decreased by the same dose of the 25-hydroxy-lactone. The 1,25-dihydroxyvitamin D3-26,23-lactone in both its natural and unnatural forms was found to be active in stimulating ICA and BCM. These results suggest that the 25-hydroxy-lactone has some biological activity in the chick and that 1,25(OH)2D3-26,23-lactone can mediate ICA and BCM biological responses, probably through an interaction with 1,25-(OH)2D3 specific receptors in these target tissues.  相似文献   

17.
This paper introduces a model for the evolution of positive HIV population and manifestation of AIDS (acquired immunideficiency syndrome). The focus is on the nature of the transference rate of HIV to AIDS. Expert knowledge indicates that the transference rate is uncertain and depends strongly on the viral load and the CD4+ level of the infected individuals. Here, we suggest to view the transference rate as a fuzzy set of the viral load and CD4+ level values. In this case the dynamic model results in a fuzzy model that preserves the biological meaning and nature of the transference rate λ. Its behavior fits the natural history of HIV infection reported in the medical science domain. The paper also includes a comparison between the fuzzy model and a classic Anderson’s model using data reported in the literature.  相似文献   

18.
Do physicians have an ethical obligation to care for patients with AIDS?   总被引:1,自引:0,他引:1  
This paper responds to the question: Do physicians have an ethical obligation to care for patients with acquired immunodeficiency syndrome (AIDS)? First, the social and political milieu in which this question arises is sampled. Here physicians as well as other members of the community are found declaring an unwillingness to be exposed to people with AIDS. Next, laws, regulations, ethical codes and principles, and the history of the practice of medicine are examined, and the literature as it pertains to these areas is reviewed. The obligation to care for patients with AIDS, however, cannot be located in an orientation to morality defined in rules and codes and an appeal to legalistic fairness. By turning to the orientation to morality that emerges naturally from connection and is defined in caring, the physicians'' ethical obligation to care for patients with AIDS is found. Through an exploration of the writings of modern medical ethicists, it is clear that the purpose of the practice of medicine is healing, which can only be accomplished in relationship to the patient. It is in relationship to patients that the physician has the opportunity for self-realization. In fact, the physician is physician in relationship to patients and only to the extent that he or she acts virtuously by being morally responsible for and to those patients. Not to do so diminishes the physician''s ethical ideal, a vision of the physician as good physician, which has consequences for the physician''s capacity to care and for the practice of medicine.  相似文献   

19.
In this study, we investigated the efficiencies by which the pET and pQE expression systems produce unnatural recombinant proteins by residue-specific incorporation of unnatural amino acids, a method through which it was found that type of gene expression system tremendously influences the production yield of unnatural proteins in Escherichia coli. Green fluorescent protein (GFP) and a single-chain Fv antibody against c-Met were utilized as model recombinant proteins while L-homopropargylglycine (Hpg), a methionine analogue that incorporates into the methionine residues of a recombinant protein, was used as model unnatural amino acid. The pET system produced an almost negligible amount of Hpg-incorporated unnatural protein compared to the amount of methionine-incorporated natural protein. However, comparable amounts of unnatural and natural protein were produced by the pQE expression system. The amount of unnatural GFP protein produced through pET expression was not increased despite the over-expression of methionyl tRNA synthetase, which can enhance the activation rate of methionyl-tRNA with a methionine analogue. Incorporation of Hpg decreased the productivity of active GFP by approximately 2.5 fold, possibly caused by the inefficient folding of Hpg-incorporated GFP. Conversely, the productivity of functional anti-c-Met sc-Fv was not influenced by incorporation of Hpg. We confirmed through LC-MS and LCMS/MS that Hpg was incorporated into the methionine residues of the recombinant proteins produced by the pQE expression system. The first two authors equally contributed to this work.  相似文献   

20.
Peterson M 《Bioethics》2008,22(6):321-327
This article discusses some ethical principles for distributing pandemic influenza vaccine and other indivisible goods. I argue that a number of principles for distributing pandemic influenza vaccine recently adopted by several national governments are morally unacceptable because they put too much emphasis on utilitarian considerations, such as the ability of the individual to contribute to society. Instead, it would be better to distribute vaccine by setting up a lottery. The argument for this view is based on a purely consequentialist account of morality; i.e. an action is right if and only if its outcome is optimal. However, unlike utilitarians I do not believe that alternatives should be ranked strictly according to the amount of happiness or preference satisfaction they bring about. Even a mere chance to get some vaccine matters morally, even if it is never realized.  相似文献   

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