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61.
There has been much debate regarding the 'double-effect' of sedatives and analgesics administered at the end-of-life, and the possibility that health professionals using these drugs are performing 'slow euthanasia.' On the one hand analgesics and sedatives can do much to relieve suffering in the terminally ill. On the other hand, they can hasten death. According to a standard view, the administration of analgesics and sedatives amounts to euthanasia when the drugs are given with an intention to hasten death. In this paper we report a small qualitative study based on interviews with 8 Australian general physicians regarding their understanding of intention in the context of questions about voluntary euthanasia, assisted suicide and particularly the use of analgesic and sedative infusions (including the possibility of voluntary or non-voluntary 'slow euthanasia'). We found a striking ambiguity and uncertainty regarding intentions amongst doctors interviewed. Some were explicit in describing a 'grey' area between palliation and euthanasia, or a continuum between the two. Not one of the respondents was consistent in distinguishing between a foreseen death and an intended death. A major theme was that 'slow euthanasia' may be more psychologically acceptable to doctors than active voluntary euthanasia by bolus injection, partly because the former would usually only result in a small loss of 'time' for patients already very close to death, but also because of the desirable ambiguities surrounding causation and intention when an infusion of analgesics and sedatives is used. The empirical and philosophical implications of these findings are discussed. 相似文献
62.
Schakowski F Buttgereit P Mazur M Märten A Schöttker B Gorschlüter M Schmidt-Wolf IG 《Genetic vaccines and therapy》2004,2(1):1-11
BACKGROUND: Tumor cells such as leukemia and lymphoma cells are possible targets for gene therapy. However, previously leukemia and lymphoma cells have been demonstrated to be resistant to most of non-viral gene transfer methods. METHODS: The aim of this study was to analyze various methods for transfection of primary leukemia cells and leukemia cell lines and to improve the efficiency of gene delivery. Here, we evaluated a novel electroporation based technique called nucleofection. This novel technique uses a combination of special electrical parameters and specific solutions to deliver the DNA directly to the cell nucleus under mild conditions. RESULTS: Using this technique for gene transfer up to 75% of primary cells derived from three acute myeloid leukemia (AML) patients and K562 cells were transfected with the green flourescent protein (GFP) reporter gene with low cytotoxicity. In addition, 49(+/- 9.7%) of HL60 leukemia cells showed expression of GFP. CONCLUSION: The non-viral transfection method described here may have an impact on the use of primary leukemia cells and leukemia cell lines in cancer gene therapy. 相似文献
63.
Erkner A Roure A Charroux B Delaage M Holway N Coré N Vola C Angelats C Pagès F Fasano L Kerridge S 《Development (Cambridge, England)》2002,129(5):1119-1129
We have carried out a genetic screen designed to isolate regulators of teashirt expression. One of these regulators is the Grunge gene, which encodes a protein with motifs found in human arginine-glutamic acid dipeptide repeat, Metastasis-associated-like and Atrophin-1 proteins. Grunge is the only Atrophin-like protein in Drosophila, whereas several exist in humans. We provide evidence that Grunge is required for the proper regulation of teashirt but also has multiple activities in fly development. First, Grunge is crucial for correct segmentation during embryogenesis via a failure in the repression of at least four segmentation genes known to regulate teashirt. Second, Grunge acts positively to regulate teashirt expression in proximoventral parts of the leg. Grunge has other regulatory functions in the leg, including the patterning of ventral parts along the entire proximodistal axis and the proper spacing of bristles in all regions. 相似文献
64.
65.
Over the past decade, umbilical cord blood (UCB) has routinely been used as a source of haematopoietic stem cells for allogeneic
stem cell transplants in the treatment of a range of malignant and non-malignant conditions affecting children and adults.
UCB banks are a necessary part of the UCB transplant program, but their establishment has raised a number of important scientific,
ethical and political issues. This paper examines the scientific and clinical evidence that has provided the basis for the
establishment of UCB banks. We also discuss the major ethical issues that UCB banks raise, including ownership of cord blood,
processes for obtaining consent for its collection and storage, and confidentiality. Finally, we review other concerns about
commercial non-altruistic banking, including concerns about social justice, equity of access and equity of care. 相似文献
66.
Three putative murine Teashirt orthologues specify trunk structures in Drosophila in the same way as the Drosophila teashirt gene 总被引:2,自引:0,他引:2
Drosophila teashirt (tsh) functions as a region-specific homeotic gene that specifies trunk identity during embryogenesis. Based on sequence homology, three tsh-like (Tsh) genes have been identified in the mouse. Their expression patterns in specific regions of the trunk, limbs and gut raise the possibility that they may play similar roles to tsh in flies. By expressing the putative mouse Tsh genes in flies, we provide evidence that they behave in a very similar way to the fly tsh gene. First, ectopic expression of any of the three mouse Tsh genes, like that of tsh, induces head to trunk homeotic transformation. Second, mouse Tsh proteins can rescue both the homeotic and the segment polarity phenotypes of a tsh null mutant. Third, following ectopic expression, the three mouse Tsh genes affect the expression of the same target genes as tsh in the Drosophila embryo. Fourth, mouse Tsh genes, like tsh, are able to induce ectopic eyes in adult flies. Finally, all Tsh proteins contain a motif that recruits the C-terminal binding protein and contributes to their repression function. As no other vertebrate or fly protein has been shown to induce such effects upon ectopic expression, these results are consistent with the idea that the three mouse Tsh genes are functionally equivalent to the Drosophila tsh gene when expressed in developing Drosophila embryos. 相似文献
67.
Phyllis M. Tookey Kerridge 《BMJ (Clinical research ed.)》1935,1(3886):1314-1317
68.
69.
The ultrastructure of the wall of Candida albicans strain 6406 was examined in polyeneresistant organisms obtained by continued incubation after the cessation of growth. The walls of organisms harvested either during the exponential phase of growth or after 24 h starvation, when examined in situ, showed the typical layered appearance. After 72 h starvation, when the resistance to amphotericin B methyl ester (AME) was 60 times greater than that of exponentially growing organisms, both the periplasmic material and the distinct electron-dense layers were absent from the wall. At this stage there was no increase in the thickness of the wall. After 144 h starvation the thickness of the wall had increased from 143 +/-22 nm (exponential phase organisms) to 211+/-58 nm. If after 144 h starvation the organisms were incubated for 1 h in fresh nutrient medium they regained their sensitivity to AME and the wall regained the periplasmic material and its characteristic multilayered appearance. During the first 24 h starvation there was a considerable fall in the soluble glucan fraction, but on continued incubation there was little change in the relative proportions of the major carbohydrate constituents of the cell. Thin sections of purified walls isolated from organisms harvested either during exponential growth or after 144 h starvation were identical in appearance and characterized by the absence of the electrondense layers observed in sections of intact cells and by a reduction in thickness to 100+/-20nm. 相似文献
70.
Genetic screens in Drosophila designed to search for loci involved in gastrulation have identified four regions of the genome that are required zygotically for the formation of the ventral furrow. For three of these, the genes responsible for the mutant phenotypes have been found. We now describe a genetic characterization of the fourth region, which encompasses the cytogenetic interval 24C3-25B, and the mapping of genes involved in gastrulation in this region. We have determined the precise breakpoints of several existing deficiencies and have generated new deficiencies. Our results show that the region contains at least three different loci associated with gastrulation effects. One maternal effect gene involved in ventral furrow formation maps at 24F but could not be identified. For a second maternal effect gene which is required for germ band extension, we identify a candidate gene, CG31660, which encodes a G protein coupled receptor. Finally, one gene acts zygotically in ventral furrow formation and we identify it as Traf4. 相似文献