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561.
Advance care planning refers to the process of determining how one wants to be cared for in the event that one is no longer competent to make one's own medical decisions. Some have argued that advance care plans often fail to be normatively binding on caretakers because those plans do not reflect the interests of patients once they enter an incompetent state. In this article, we argue that when the core medical ethical principles of respect for patient autonomy, honest and adequate disclosure of information, institutional transparency, and concern for patient welfare are upheld, a policy that would allow for the disregard of advance care plans is self‐defeating. This is because when the four principles are upheld, a patient's willingness to undergo treatment depends critically on the willingness of her caretakers to honor the wishes she has outlined in her advance care plan. A patient who fears that her caretakers will not honor her wishes may choose to avoid medical care so as to limit the influence of her caretakers in the future, which may lead to worse medical outcomes than if she had undergone care. In order to avoid worse medical outcomes and uphold the four core principles, caregivers who are concerned about the future welfare of their patients should focus on improving advance care planning and commit to honoring their patients’ advance care plans. 相似文献
562.
Aidan K Curran Daniel Peraza Cheryl A Elinsky J C Leiter 《Journal of applied physiology》2002,92(6):2554-2564
The rostral ventral medulla (RVM) may be important in the control of cardiorespiratory interactions. We hypothesized that inhibition of the RVM would enhance inhibition of breathing associated with transient blood pressure elevations. In 25 piglets 3-16 days of age, we studied the effect of acutely increasing blood pressure, by systemic infusion of phenylephrine, on respiratory activity before and after inhibition of neural activity in the RVM by dialysis of 10 mM muscimol, a GABA(A)-receptor agonist. Muscimol dialysis through probes that were placed along the ventral medullary surface from approximately 1 mm rostral to the facial nucleus to approximately 0.5 mm caudal to the facial nucleus augmented the respiratory inhibition associated with acute increases in blood pressure. No similar enhancement of respiratory inhibition after phenylephrine treatment was seen in six control animals that did not receive muscimol dialysis. We conclude that the piglet RVM participates in cardiorespiratory interactions and that dysfunction of homologous regions in the human infant could lead to cardiorespiratory instability and may be involved in the pathogenesis of sudden infant death syndrome. 相似文献
563.
Bauxite residue disposal areas may be amended and re‐vegetated to facilitate the ecosystem restoration process. However, the development of the belowground system during restoration is frequently overlooked. In turn, although vegetation establishment on bauxite residue is well studied, virtually nothing is known about concurrent changes in the soil biota. In order to understand how different amendments and re‐vegetation influence the belowground community, we compared nematode assemblages from bauxite residues that differed in their treatment history (compost addition, gypsum addition, and time since re‐vegetation), and examined whether any differences were related to changes in soil properties. No nematodes were present in the unamended treatment, thus indicating a need for amelioration of substrate properties. However, there were differences in the nematode assemblage between the other amended treatments. The quantity of gypsum reduced nematode density, but had no effect on taxa richness or the Maturity Index in treatments amended in the same year. Nematode taxa richness and the Maturity Index were greatest in the treatment re‐vegetated earliest. Moreover, the Maturity Index was negatively correlated to soil pH and percentage Na. These findings indicate that sufficient amendment and re‐vegetation are crucial to address inhibitory characteristics of the residue and aid restoration of the belowground system in bauxite residues. 相似文献
564.
In Ireland much of the land available for plantation establishment requires some degree of soil cultivation and drainage to
improve its suitability for tree growth. The method of cultivation and drainage normally varies depending upon the soil type
and its drainage characteristics. Little research has been carried out on the impact of practices such as mounding and mole
drainage upon rooting and biomass production in young crops. The research reported in this paper was carried out on four sites
where the general soil type was surface water gley. Three of the sites studied were afforestations on old farmland, while
the fourth site was a reforestation of a windblown stand. The cultivation methods investigated included mounding, mole drainage
with mounds, mole drainage only and ripping. Sitka spruce trees ranging in age from five to thirty years were excavated from
these experimental sites to describe the impact of different soil cultivation techniques upon root architecture and above
and below ground biomass production. The results showed that while the effect of mound drainage upon water table level varied
from site to site, the establishment of trees on mounds led to an increase in above and below ground biomass production. Mole
drainage of these sites without mounds, did not lead to any increase in root or shoot development when compared with trees
growing on uncultivated/undrained ground.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
565.
566.
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568.
Aidan Hollis 《CMAJ》2015,187(14):1033-1034
569.
A conceptual framework for predicting temperate ecosystem sensitivity to human impacts on fire regimes 总被引:2,自引:0,他引:2
570.
Lactococcus lactis subsp. lactis biovar. diacetylactis DPC721 is a spontaneous bacteriophage insensitive mutant of strain DPC220, isolated after challenge with an industrial bacteriophage, phi D1. Plasmid analysis demonstrated that the bacteriophage insensitivity was associated with the absence of two native DPC220 plasmids (pAH82 and pAH33), and the presence of a novel plasmid (pAH90) in DPC721. The plasmids were transferred by conjugative mobilization to a plasmid free background where it was confirmed by restriction mapping that pAH90 is a co-integrate formed by the precise recombination of pAH82 and pAH33. The resistance phenotype encoded by pAH90 was also active against two bacteriophage homologous for the plasmid-free strain. Plasmid pAH90 was shown to encode at least two independent resistance mechanisms, including an adsorption-inhibition mechanism and a restriction and modification system. The adsorption-inhibition mechanism encoded by the co-integrate plasmid was specific for one of the phage used in this study. 相似文献