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41.
The purpose of the study reported in this paper was to explore the coping strategies of heart transplant recipients. Using a qualitative research approach, interviews were conducted with 42 participants (35 men and seven women). Analysis of the data revealed eight coping strategies: acceptance/optimism, denial/avoidance, setting targets, comparing oneself with others, making attributions, seeking social support, having faith and changing priorities and perceptions. These are discussed in relation to the literature and a tentative model of coping after heart transplantation is offered. The findings may provide pointers to health professionals about ways in which they can improve support for heart transplant recipients and their families.  相似文献   
42.
The potential of 99m-Tc-J001 for the investigation of inflammatory lesions via the targeting of recruited macrophages (Mφ) has already been documented in several experimental models and in human diseases. To achieve a functional imaging of inflammation via Mφ targeting, minimal labeled colloid content and high in vivo stability of 99mTc-J001 are essential. The actual specificity of such scintigraphy is closely dependent upon the radiolabeling of only the J001 molecules available for Mφ targeting. To develop an appropriate radiopharmaceutical kit, optimization of the labeling conditions was achieved from a series of pilot formulations that were evaluated for radiolabeling efficiency and both in vitro and in vivo 99mTc-J001 stability. Colloids were characterized using autocorrelation spectroscopy and multiangle laser-light scattering, radioactive colloid content of the formulations being deduced from biodistribution studies. This work has made possible the definition of a formulation exhibiting a radiolabeling yield >97.0%, associated with in vivo stability and minimal colloid formation, thus greatly enhancing the specificity of such macrophage scintigraphy.  相似文献   
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44.
Avoiding blood products during liver transplantation   总被引:2,自引:0,他引:2  
Liver transplantation is a major surgical procedure usually requiring large amount of blood products (red cells, platelets, fresh-frozen plasma). We developed a multidisciplinary transfusion-free protocol for liver transplantation in Jehovah's witnesses who refuse the use of blood products but accept organ transplantation. Between September 1998 and November 2004, 9 of 29 Jehovah's witnesses evaluated for liver transplantation were transplanted after medical preparation. None of these patients received any blood product during the surgical procedure. This experience may be beneficial for the entire liver transplantation population, as excessive transfusion has been linked to increased morbidity and mortality in liver transplantation.  相似文献   
45.
A series of atomistic simulations was performed to assess the ability of the Schulten dissolved organic matter (DOM) molecule, a well-established model humic molecule, to reproduce the physical and chemical behavior of natural humic substances. The unhydrated DOM molecule had a bulk density value appropriate to humic matter, but its Hildebrand solubility parameter was lower than the range of current experimental estimates. Under hydrated conditions, the DOM molecule went through conformational adjustments that resulted in disruption of intramolecular hydrogen bonds (H-bonds), although few water molecules penetrated the organic interior. The radius of gyration of the hydrated DOM molecule was similar to those measured for aquatic humic substances. To simulate humic materials under aqueous conditions with varying pH levels, carboxyl groups were deprotonated, and hydrated Na+ or Ca2+ were added to balance the resulting negative charge. Because of intrusion of the cation hydrates, the model metal-humic structures were more porous, had greater solvent-accessible surface areas, and formed more H-bonds with water than the protonated, hydrated DOM molecule. Relative to Na+, Ca2+ was both more strongly bound to carboxylate groups and more fully hydrated. This difference was attributed to the higher charge of the divalent cation. The Ca-DOM hydrate, however, featured fewer H-bonds than the Na-DOM hydrate, perhaps because of the reduced orientational freedom of organic moieties and water molecules imposed by Ca2+. The present work is, to our knowledge, the first rigorous computational exploration regarding the behavior of a model humic molecule under a range of physical conditions typical of soil and water systems.  相似文献   
46.
BACKGROUND: The importance of traditional medicine, one of the fundamentals of the cultural heritage of African, Asian and South American peoples, is evident in that such medicine is practised by more than 80% of these populations. METHODS: To analyse the methodology of clinical trials using medicinal plants, we reviewed articles published on this topic between 1980 and 2000. RESULTS: Forty-eight clinical trials were identified. Most were carried out in developed countries. Standard methodological principles were applied in almost all the trials: randomisation (85.4%), comparison (87.5%) versus placebo (95.2%), and blinded design (81.3%). The duration of the studies was short. Sample sizes were generally small, ranging from 30 to 99 subjects; statistical tests were used in 90% of the trials. Adverse effects were infrequently collected. CONCLUSION: Most clinical trials included in this survey were conducted in accordance with WHO guidelines. Respect for methodological principles and the implementation of a legislative framework are important in obtaining credibility and international recognition of the traditional pharmacopoeia.  相似文献   
47.
48.
Red wine polyphenolic compounds (RWPCs) are potent inducers of endothelium-dependent relaxations of coronary arteries, which involve both nitric oxide and endothelium-derived hyperpolarizing factor (EDHF). The EDHF-mediated relaxation to RWPCs is critically dependent on the formation of reactive oxygen species by a flavin-dependent enzyme. The aim of the present study was to determine the role of redox-sensitive protein kinases including p38 MAPK, ERK1/2 and PI3-kinase/Akt in RWPCs-induced EDHF-mediated relaxation. Porcine coronary artery rings were suspended in organ chambers for measurement of changes in isometric tension. Confluent cultures of porcine coronary artery endothelial cells were used to determine the phosphorylation level of p38 MAPK, ERK1/2 and Akt by Western blot analysis. All experiments were performed in the presence of indomethacin and Nomega-nitro-L-arginine. RWPCs caused pronounced endothelium-dependent relaxations, which were significantly reduced by wortmannin and LY294002, two inhibitors of PI3-kinase, and not affected by PD98059 (an inhibitor of ERK1/2 kinase kinase) and SB203580 (an inhibitor of p38 MAPK). In contrast, wortmannin did not affect relaxations to bradykinin or levcromakalim. RWPCs elicited within minutes a sustained and concentration-dependent phosphorylation of p38 MAPK, ERK1/2 and Akt in endothelial cells. The phosphorylation of Akt in response to RWPCs was abolished by wortmannin and LY294002, and by the membrane-permeant analogue of superoxide dismutase Mn(III)tetrakis(1-methyl-4-pyridyl)porphyrin. The present findings demonstrate that RWPCs cause EDHF-mediated relaxations of coronary arteries; these responses are critically dependent on the redox-sensitive activation of the PI3-kinase/Akt pathway in endothelial cells.  相似文献   
49.
The vast majority of community nutrition/health programs in developing countries focus on women of reproductive age (WRA) and a few explicitly involve senior women, or grandmothers. In Senegal, as in many other places, older, experienced women play an influential role in household maternal and child health (MCH) matters. Formative research in Serer villages revealed their importance and this was taken into account in an action research nutrition education (NE) project in which grandmothers were encouraged to promote improved nutritional practices related to pregnancy (e.g. decreased work and improved diet) and infant feeding (e.g. breastfeeding and complementary feeding). A participatory communication/empowerment education approach was used involving songs, stories and group discussion. Quantitative and qualitative data were collected to both document and evaluate the intervention. Triangulation of the evaluation data suggests that 12 months after the intervention was initiated there were significant improvements in grandmothers' nutritional knowledge, in their advice to WRA, and in the nutrition-related practices of these younger women associated both with pregnancy and infant feeding. For example, in the pre-test only 20% of grandmothers stated that they advise pregnant women to decrease their workload whereas in the post-test 87% reported giving this advice. At the same time, 91% of WRA in villages with the grandmother strategy reported having decreased their workload during their last pregnancy whereas in villages with NE activities for WRA but not with grandmothers, only 34% of younger women reported having done so. These findings provide evidence of grandmothers' ability to learn, to integrate new information into their practices and to positively influence the practices of WRA. These results support the need for future MCH programs, in different cultural contexts, to involve grandmothers and in so doing to build on their intrinsic commitment to family well-being.  相似文献   
50.
New alkaloids from Cephalotaxus fortunei   总被引:4,自引:0,他引:4  
Four new cephalotaxus alkaloids, cephalotaxine alpha-N-oxide (1), cephalotaxine beta-N-oxide (2), 11-beta-hydroxycephalotaxine beta-N-oxide (3), and isocephalotaxine (4), were isolated, together with several known alkaloids from an EtOAc extract of the fruits of Cephalotaxus fortunei. The structures were determined by spectral analysis including mass spectrometry and 2D NMR. Compounds 1, 2, 3, and 4 displayed cytotoxicity against nasopharynx KB cells with IC50 values of 30, 14, 31, and 15 micro g/mL, respectively.  相似文献   
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