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1.
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
2.
Jeff A Johnson Heather RL Lerner Pamela C Rasmussen David P Mindell 《BMC evolutionary biology》2006,6(1):65-12
Background
Populations of the Oriental White-backed Vulture (Gyps bengalensis) have declined by over 95% within the past decade. This decline is largely due to incidental consumption of the non-steroidal anti-inflammatory veterinary pharmaceutical diclofenac, commonly used to treat domestic livestock. The conservation status of other Gyps vultures in southern Asia is also of immediate concern, given the lack of knowledge regarding status of their populations and the continuing existence of taxonomic uncertainties. In this study, we assess phylogenetic relationships for all recognized species and the majority of subspecies within the genus Gyps. The continuing veterinary use of diclofenac is an unknown but potential risk to related species with similar feeding habits to Gyps bengalensis. Therefore, an accurate assessment of the phylogenetic relationships among Gyps vultures should aid in their conservation by clarifying taxonomic uncertainties, and enabling inference of their respective relatedness to susceptible G. bengalensis. 相似文献3.
Effects of atropine on respiratory heat loss in asthma 总被引:4,自引:0,他引:4
Breslin F. J.; McFadden E. R. Jr; Ingram R. H. Jr; Deal E. C. Jr 《Journal of applied physiology》1980,48(4):619-623
4.
The vertebrate head is an extremely complicated structure: development of the head requires tissue-tissue interactions between derivates of all the germ layers and coordinated morphogenetic movements in three dimensions. In this review, we highlight a number of recent embryological studies, using chicken, frog, zebrafish and mouse, which have identified crucial signaling centers in the embryonic face. These studies demonstrate how small variations in growth factor signaling can lead to a diversity of phenotypic outcomes. We also discuss novel genetic studies, in human, mouse and zebrafish, which describe cell biological mechanisms fundamental to the growth and morphogenesis of the craniofacial skeleton. Together, these findings underscore the complex interactions leading to species-specific morphology. These and future studies will improve our understanding of the genetic and environmental influences underlying human craniofacial anomalies. 相似文献
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Stephen G Bennett James A Comer Heather M Smith James P Webb 《Journal of vector ecology》2007,32(2):198-201
We detected antibodies reactive with Rickettsia akari, the etiologic agent of rickettsialpox in humans and in 83 of 359 (23%) rodents belonging to several species, collected in Orange County, CA. Reciprocal antibody titers >1:16 to R. akari were detected in native mice and rats (Peromyscus maniculatus, P. eremicus, and Neotoma fuscipes) and in Old World mice and rats (Mus musculus, Rattus rattus, and R. norvegicus), representing the first time that antibodies reactive with this agent have been detected in four of these species and the first report of these antibodies in rodents and humans west of the Mississippi River. We then tested serum samples from individuals who used a free clinic in downtown Los Angeles and found that 25 of 299 (8%) of these individuals had antibody titers >1:64 to R. akari. Serologic evidence suggested that R. akari or a closely related rickettsia is prevalent among several rodent species at these localities and that infection spills over into certain segments of the human population. Isolation or molecular confirmation of the agent is needed to conclusively state that R. akari is the etiologic agent infecting these rodents. 相似文献
9.
Chlorsulfuron, an inhibitor of acetolactate synthase (EC 4.1.3.18) (TB Ray 1984 Plant Physiol 75: 827-831), markedly inhibited the growth of Lemna minor at concentrations of 10−8 molar and above, but had no inhibitory effects on growth at 10−9 molar. At growth inhibitory concentrations, chlorsulfuron caused a pronounced increase in total free amino acid levels within 24 hours. Valine, leucine, and isoleucine, however, became smaller percentages of the total free amino acid pool as the concentration of chlorsulfuron was increased. At concentrations of chlorsulfuron of 10−8 molar and above, a new amino acid was accumulated in the free pool. This amino acid was identified as α-amino-n-butyrate by chemical ionization and electron impact gas chromatography-mass spectrometry. The amount of α-amino-n-butyrate increased from undetectable levels in untreated plants, to as high as 840 nanomoles per gram fresh weight (2.44% of the total free pool) in plants treated with 10−4 molar chlorsulfuron for 24 hours. The accumulation of this amino acid was completely inhibited by methionine sulfoximine. Chlorsulfuron did not inhibit the methionine sulfoximine induced accumulations of valine, leucine, and isoleucine, supporting the idea that the accumulation of the branched-chain amino acids in methionine sulfoximine treated plants is the result of protein turnover rather than enhanced synthesis. Protein turnover may be primarily responsible for the failure to achieve complete depletion of valine, leucine, and isoleucine even at concentrations of chlorsulfuron some 104 times greater than that required to inhibit growth. Tracer studies with 15N demonstrate that chlorsulfuron inhibits the incorporation of 15N into valine, leucine, and isoleucine. The α-amino-n-butyrate accumulated in the presence of chlorsulfuron and [15N]H4+ was heavily labeled with 15N at early time points and appeared to be derived by transamination from a rapidly labeled amino acid such as glutamate or alanine. We propose that chlorsulfuron inhibition of acetolactate synthase may lead to accumulation of 2-oxobutyrate in the isoleucine branch of the pathway, and transamination of 2-oxobutyrate to α-amino-n-butyrate by a constitutive transaminase utilizing either glutamate or alanine as α-amino-N donors. 相似文献
10.
The antagonistic and colonistic effect of post-inoculation temperature and light intensity was investigated in a factorial experiment involving four Cladosporium spp., three poplar cultivars, two levels of temperature and light intensity, anda race of Melampsora larici-populina. The species of Cladosporium were more antagonistic to uredinial production on the inoculated leaf discs of the cultivars when these were incubated in high temperature – high light intensity than in any other regime. Whilst colonisation of the uredinia was usually minimal in discs incubated on the high temperature – high light intensity regime, the condition of incubation favouring maximum colonisation varied with the cultivar and the species of Cladosporium employed. All the major factors and most of their two-, three- and four-way interactions were significant determinants of variation in both antagonism to uredinial production and in colonisation of the uredinia produced. The validity ofextrapolation from such experiments to the field environment is discussed. 相似文献