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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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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   
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Summary Rhigonema infecta (Leidy, 1849) Christie & Cobb, 1927, a member of the family Rhigonematidae sensu Théodoridès, 1965, is redescribed from the diplopod Narceus annularis from Sharbot Lake and Long Point, Ontario, Canada. R. infecta is most similar to R. subtruncatum Dollfus, 1952 but differs from this species in possessing four rather than three post-cloacal papillae in the male. Rhigonematids have been affiliated with members of the order Oxyurida by most authors but study of R. infecta suggests that rhigonematids should be placed in their own order, the Rhigonematida. Members of the order Rhigonematida are characterized by: two spicules in the male; H-shaped excretory system; are round to oval sperms; thick and smooth egg-shell; apparently lacking a uterine layer; and development in the egg involving no moults and resulting in a long, thin, coiled larva. In contrast, oxyuridans have a single spicule, the excretory system is X-shaped, the sperm is comet-shaped and the egg-shell has a prominent striated uterine layer. Development in the egg involves at least one and probably two moults and results in a short, robust, uncoiled larva. ac]19810310  相似文献   
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Summary Both carotid bodies from 26 patients coming to necropsy were fixed in 10% neutral buffered formalin and sections 4 m thick were stained for various peptides by use of the immunogold technique. The results show that the human carotid body contains met- and leu-enkephalin, substance P, vasoactive intestinal peptide (VIP), neurotensin and bombesin. The distribution of these six peptides within the carotid body differs. Thus met- and leu-enkephalin are both present predominantly within glomic chief cells but with a marked tendency to favour the dark variant of these cells. Substance P and VIP both show a weak immunoreactivity in comparison to the enkephalins and are present in all three variants of chief cell. Neurotensin shows the weakest immunoreactivity of all and is restricted to a few glomic chief cells in a minority of cases. Bombesin also shows a weak immunoreactivity in glomic chief cells but a strong reaction in glomic arteries and arterioles. In these vessels bombesin appears to be confined to smooth muscle cells in the media but we cannot say whether it is secreted by them or merely bound to receptor sites on their membranes. These findings are related to quantitative data on the concentration of peptides in the human carotid body from a previous paper with which we were associated.  相似文献   
9.
Analysis of a transformed cell line using antisense c-fos RNA   总被引:2,自引:0,他引:2  
Simian sarcoma virus (SSV)-infected NIH-3T3 cells (SSV-NIH-3T3), express a homologue of platelet-derived growth factor, (PDGF) a powerful inducer of the c-fos gene. We have used these cells to test the hypothesis that autocrine stimulation by PDGF-like molecules leads to c-fos expression which is functional in the transformed phenotype. We have transfected SSV-NIH-3T3 cells with a c-fos antisense-RNA expression vector, pSVsof, or control plasmids. pSVsof-transfected cells exhibit markedly decreased c-fos mRNA and protein levels, restored density-dependent growth arrest and reduced (three of five clones) tumorigenicity compared to control lines. The results confirm that c-fos cooperates in the transformed phenotype of SSV-NIH-3T3 cells.  相似文献   
10.
Summary The functional integrity of the QUTB gene (encoding quinate dehydrogenase) has been confirmed by transformation of a qutB mutant strain. The DNA sequence of the contiguous genes QUTD (quinate permease), QUTB and QUTG (function unknown) has been determined and analysed, together with that of QUTE (catabolic 3-dehydroquinase). The QUTB sequence shows significant homology with the shikimate dehydrogenase function of the complex AROM locus of Aspergillus nidulans, and with the QA-3 quinate dehydrogenase and QA-1S (repressor) genes of Neurospora crassa. The QUTD gene shows strong homology with the N. crassa QA-Y gene and QUTG with the QA-X gene. QUTD, QUTB, and QUTG, QUTE form two pairs of divergently transcribed genes, and conserved sequence motifs identified in the two common 5 non-coding regions show significant homology with UAS GAL and UAS QA sequences of the Saccharomyces cerevisiae and N. crassa Gal and QA systems. In addition, conserved 5 sequences homologous to the mammalian CAAT box are noted and a previously unreported conserved 22 nucleotide motif is presented.  相似文献   
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