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Abstract. Registered nurses regarded as “experienced and good” in dementia care were interviewed about the feeding of a severely demented patient who showed refusal-like feeding behaviour. Not one of the twenty nurses could see herself using force against her patients. Most interviewees justified their decisions to feed a severely demented patient and answered questions about whether they would change their minds if there were certain circumstances in terms of words that could be interpreted as referring to the ethical principle of beneficence. The nurses stressed the difficulty to understand the meaning of severely demented patients' feeding behaviour and decide when force-feeding occurs. When asked to rank ethical principles of importance for the decision, however, the most common answer was that they would give priority to the ethical principle of autonomy. The nurses did not see the ethical principles as separate entities, that could be applied one by one, but tried to integrate them into a whole. The findings of this study were interpreted as indicating that principled ethics is not an adequate model to describe experienced nurses' ethical reasoning. 相似文献
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人胎儿雪旺氏细胞的体外培养及其纯化研究 总被引:3,自引:1,他引:2
本实验用酶消化法从孕14~19周人胎儿周围神经中分离培养雪旺氏细胞,结合差速贴壁和阿糖胞苷处理进行纯化,根据S-100蛋白免疫细胞化学染色和形态学特征,分析不同时期雪旺氏细胞的纯化程度。实验结果显示:培养4d,倒置相差显微镜下观察,雪旺氏细胞呈典型的双极或三极形,端对端或旋涡状排列,S-100蛋白免疫细胞化学染色呈阳性反应,其比例约占98%;在2~3周内,雪旺氏细胞的纯度维持在85%~90%;培养35d,雪旺氏细胞约占80%;单纯采用阿糖胞苷或差速贴壁处理,培养35d,雪旺氏细胞约占70%;原代培养92d,传代11代细胞生长良好。实验结果表明,多种方法联合使用较单一方法所得的纯度高。本方法快速、简便,能为雪旺氏细胞作为移植材料提供足够的来源。 相似文献
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目的通过对甘肃农产区居民的饮食习惯、营养知识和态度的调查,从需方的角度对开展面粉营养素强化的可行性进行探讨。方法采用定性和定量调查相结合的方法,对4个地区的城市和农村的男性和女性分别进行现状和原因的调查分析。结果被调查地区多数城市(92.7%)和农村(60.7%)家庭日常饮食以面食为主,94.7%的城市家庭购买面粉,而在农村地区,多数家庭自己种植或购买小麦。城市居民较农村对营养和维生素有更多的了解和关注。农村男性对面粉营养素强化持怀疑态度,女性更加关注孩子的营养,认为目前的饮食单一,孩子可能营养不足。结论与农村地区相比,城市地区的社会经济条件和知识基础较利于开展面粉强化工作。 相似文献
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Joensen L Borda E Kohout T Perry S García G Sterin-Borda L 《Molecular and biochemical parasitology》2003,127(2):169-177
Previously, we have demonstrated that plasma membranes from the parasite Trypanosoma cruzi (T. cruzi) recognize and adhere to host cells through parasite surface attachment molecules that have affinity for beta(1)-adrenergic receptors (beta(1)-ARs) on target organs. In this report we identify a parasite protein that not only interacts with beta(1)-ARs, but also displays beta-agonist-like activity. We demonstrate that a recombinant maltose binding protein fusion of Tc13 Tul (MBP-Tc13 Tul), a member of the T. cruzi antigen 13 family of surface antigen proteins, competes for binding sites with the beta-adrenergic receptor antagonist [125I]-CYP on membranes purified both from CHO cells expressing human beta(1)-ARs and from rat atria. The competition is prevented by pre-treating MBP-Tc13 Tul with antibodies directed against the EPKSA repeat domain of Tc13 Tul, implicating this portion of the molecule in binding to the beta(1)-AR. Furthermore, MBP-Tc13 Tul activates rat myocardial beta(1)-ARs, resulting in synthesis of cyclic adenosine monophosphate (cAMP) and an increase in cardiac contractility. These biological effects are selectively suppressed by the beta(1)-AR antagonist atenolol, by a synthetic peptide corresponding to the second extracellular loop of the human beta(1)-AR, and by the anti-EPKSA repeat antibodies. These results imply that the Tc13 Tul cell-surface antigen of T. cruzi plays a central role in misregulating the beta(1)-AR following parasite infection, and may be a causative factor of dysautonomic syndrome described in Chagas' disease. 相似文献
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Bjrn Folkow Margareta Hallback Yen Lundgren Lilian Weiss 《Acta physiologica (Oxford, England)》1972,84(4):512-523
Newborn litters of spontaneously hypertensive rats (SHR) and normotensive control rats (NCR) were identically treated with sympathetic nerve growth factor antiserum (Wellcome) which markedly interferes with adrenergic cardiovascular control (Zaimis 1967). Blood pressure, measured intermittently during 8 months, was in treated SHR (SHRis) about 25 % higher than in NCRis, their respective pressures being about 40 % and 25 % lower than those of sham-treated SHR and NCR.–The hindquarters of one SHRis, or NCRis, were then perfused at constant flow in parallel with those of ordinary NCR. Starting from maximal vasodilatation, resistance increases were induced by graded noradrenaline (NA) infusions, from “threshold” to maximal pressor responses. Compared to NCRis, SHRis showed an increased resistance at maximal dilatation, an increased slope of the NA dose-response curve and an increased maximal pressor response, while their NA “thresholds” did not differ significantly. Thus, the structurally determined hemodynamic differences between ordinary SHR and NCR (Folkow et al. 1970 b) characterize also SHRis and NCRis, though to a reduced extent. Even when comparing SHRis with ordinary- NCR, which exhibited similar “resting” pressures, these differences partly remain, suggesting that the SHR resistance vessels might, for genetic reasons, be more prone to adapt structurally to pressure loads than those of NCR. 相似文献