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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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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
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The external shape and thickness of the enamel component of primate molars have been employed extensively in phylogenetic studies of primate relationships. The dentine component of the molar crown also has been suggested to be indicative of phylogenetic relationships, but few studies have quantified dentine morphology in order to evaluate this possibility. To explore the utility of dentine shape as an indicator of phylogenetic affinity, a two-dimensional geometric morphometric analysis (EDMA-II) was performed using nine homologous land-marks on a sample of sectioned maxillary molars of extant ceboid, cercopithecoid, and hominoid primates. Results indicate that dentine shape (the configuration of the enamel-dentine junction, or EDJ) can distinguish taxa at every taxonomic level examined, including superfamilies, subfamilies, and closely related genera and species. This supports the idea that dentine morphology may be useful for phylogenetic studies. It is further suggested that the morphology of the EDJ may be more conservative than enamel morphology, and perhaps better-suited to phylogenetic studies. Among the samples studied, cercopithecoid primates have a unique dentine shape, and it is suggested that the development of bilophodont molars may be related to the distinctive EDJ configuration in cercopithecoids. 相似文献
7.
The results of the measurement of vitamin B(12) absorption by counting the radioactivity of 5 ml. serum obtained eight to 10 hours after the ingestion of an oral dose of 0.5 mug. vitamin B(12) labelled with 0.5 muc. (57)Co are compared with those obtained with the urinary excretion (Schilling) test. Inadequate urine collection and impaired renal function were responsible for low results in the Schilling test in four of the 12 control subjects, and an incomplete urine collection in four patients with pernicious anaemia could have led to doubt about the validity of the low result.The measurement of serum radioactivity for 1,000 seconds gave conclusive results, the range in the patients with malabsorption of vitamin B(12) being between 0 and 24 counts per minute, and in the control subjects and other patients with megaloblastic anaemia between 28 and 64 counts per minute. The highest serum radioactivity level in a patient with pernicious anaemia was 19 counts per minute.Serum counting is simpler than the Schilling test and may be done alone when the patient's renal function is known to be poor, when urine collection is expected to be unreliable, or when the flushing dose of vitamin B(12) should be avoided. Otherwise there is an advantage in doing both tests together for confirmation. 相似文献
8.
Spyridon N. Karras Theocharis Koufakis Lilian Adamidou Vasiliki Antonopoulou Paraskevi Karalazou Katerina Thisiadou 《International journal of food sciences and nutrition》2021,72(1):82-92
AbstractFor seven weeks, 37 overweight adults followed a hypocaloric diet based on Orthodox Fasting (OF). A hypocaloric, time restricted eating (TRE) plan (eating between 08:00 to 16:00?h, water fasting from 16:00 to 08:00?h) was followed by 23 Body Mass Index (BMI)-matched participants. Anthropometric, glycaemic and inflammation markers and serum lipids were assessed before and after the diets. Both OF and TRE groups demonstrated reductions in BMI (28.54?±?5.45 vs 27.20?±?5.10?kg/m2, p?<?0.001 and 26.40?±?4.11 vs 25.81?±?3.78?kg/m2 p?=?0.001, respectively). Following the intervention, the OF group presented lower concentrations of total and low-density lipoprotein-cholesterol, compared with the pre-fasting values (178.40?±?34.14 vs 197.17?±?34.30?mg/dl, p?<?0.001 and 105.89?±?28.08 vs 122.37?±?29.70?mg/dl, p?<?0.001, respectively). Neither group manifested significant differences in glycaemic and inflammatory parameters. Our findings suggest that OF has superior lipid lowering effects than the TRE pattern. 相似文献
9.
Mariola Andrzejewska Lilian Yepez-Mulia Amparo Tapia Roberto Cedillo-Rivera Agnieszka E Laudy Bohdan J Staro?ciak Zygmunt Kazimierczuk 《European journal of pharmaceutical sciences》2004,21(2-3):323-329
The synthesis and some germicidal activities in vitro of two congener series of S-substituted 4,6-dihalogeno-2-mercapto-1H-benzimidazoles are reported. There was no substantial difference between antibacterial activities of corresponding 4,6-dichloro- and 4,6-dibromo-derivatives. The present results confirm lower susceptibility to substituted benzimidazoles of Gram-negative compared to Gram-positive bacteria. Minimum inhibitory concentrations (MICs) of a majority of the novel derivatives ranged between 25 and 100microg/ml for Gram-positive bacteria. The most active compounds (MICs for Gram-positive bacteria: 0.78-50microg/ml) were 4,6-dichloro-2-(4-nitrobenzylthio)-1H-benzimidazole and 4,6-dibromo-2-(4-nitrobenzylthio)-1H-benzimidazole that were 4-32 times more potent than nitrofurantoin against all Gram-positive bacteria utilized but Escherichia faecalis, against which they were, respectively, 2 and 4 times less potent than nitrofurantoin. Among Gram-negative bacteria used, Stenotrophomonas maltophilia and Bordetella bronchiseptica were most sensitive (as evidenced by a number of MICs =100microg/ml), whereas Pseudomonas aeruginosa was most resistant to the new benzimidazole derivatives (all MICs >400microg/ml). All the new compounds were at least several times more active against Giardia intestinalis (IC(50): 0.006-0.053microg/ml), and a half of them were at least several times more active against Trichomonas vaginalis (IC(50): 0.0015-0.182microg/ml) than metronidazole (IC(50): 0.210 and 0.037microg/ml, respectively), the drug of choice in the treatment of G. intestinalis and T. vaginalis infections. 相似文献
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