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61.
This paper reports the development of a theoretical model of relatives' coping approaches during the patient's intensive care unit stay and subsequent recovery at home by performing an analysis of concepts generated from two empirically grounded, theoretical studies in this area. BACKGROUND: When supporting relatives of intensive care unit patients, it is important that nurses have access to evidence-based knowledge of relatives' coping approaches during the period of illness and recovery. METHOD: Simultaneous concept analysis was used to refine and combine multiple coping concepts into a theoretical model of coping. The concepts were generated in two previous empirical studies of relatives' coping approaches during mechanically ventilated patients' intensive care unit stays and recovery at home. FINDINGS: The theoretical model was developed in 2004-2005 and illustrates the effectiveness of different coping approaches in relation to each other and to social support. Definitions summarizing each coping approach and containing the knowledge gained through the simultaneous concept analysis method were also formulated. CONCLUSION: This middle-range theory of relatives' coping approaches may make a valuable contribution to international intensive care unit nursing practice, especially as it is based on empirical studies and may therefore serve as a basis for the development of future clinical guidelines. However, the theoretical model needs to be empirically validated before it can be used.  相似文献   
62.
AIMS: The ESC/ACC redefined myocardial infarction as any amount of necrosis caused by ischaemia. The aim of this study was to describe the management and outcomes using 'real-world' data taking the new definition of acute myocardial infarction into account. METHODS AND RESULTS: A total of 2,151 consecutive patients (76.0% men) with a myocardial infarction were enrolled at 56 centres in France. The median delay to presentation was shorter in patients with ST-segment elevation myocardial infarction (STEMI) vs. non-STEMI (NSTEMI) (4 vs. 7 h, P < 0.0001). STEMI patients were more likely to receive fibrinolysis (28.9 vs. 0.7%, P < 0.0001) or undergo PCI (71.0 vs. 51.6%, P < 0.0001) but less likely to have bypass surgery (3.1 vs. 4.9%, P < 0.05). At discharge, patients with STEMI received more aggressive secondary prevention therapies than those with NSTEMI, which was not supported by differences in disease severity. A total of 1878 patients were followed-up for 1 year: 36.7% of STEMI and 41.5% of NSTEMI patients were rehospitalized (P = 0.05); 16% in both groups were revascularized. In-hospital mortality was similar (4.6 vs. 4.3%), and 1-year mortality was 9.0% in STEMI patients and 11.6% in NSTEMI patients (Log-Rank P = 0.09). Independent correlates of in-hospital mortality were untreated dyslipidaemia, advanced age, diabetes, and low blood pressure. The strongest predictors of 1-year mortality were heart failure and age. Similar predictors were found in STEMI and NSTEMI subgroups. CONCLUSIONS: Despite different management, patients with STEMI and NSTEMI have similar prognoses and independent correlates of outcome. These findings support the new definition of myocardial infarction.  相似文献   
63.
We tested the ability of avicins, a family of triterpenoid saponins obtained from Acacia victoriae (Bentham) (Leguminosae: Mimosoideae), to inhibit chemically induced mouse skin carcinogenesis. Varying doses of avicins were applied to shaved dorsal skin of SENCAR mice 15 min before application of 100 nmol of 7,12-dimethylbenz[a]anthracene (DMBA) twice a week for 4 weeks (complete carcinogenesis model). The dorsal skin of a second group of mice was treated with one dose of 10 nmol of DMBA. Avicins were then applied 15 min before repetitive doses of 2 microg of phorbol 12-tetradecanoate 13-acetate (TPA) twice a week for 8 weeks (initiation/promotion model). At 12 weeks, avicins produced a 70% decrease in the number of mice with papillomas and a greater than 90% reduction in the number of papillomas per mouse in both protocols. We also observed a 62% and 74% reduction by avicins in H-ras mutations at codon 61 in the DMBA and DMBA/TPA models, respectively, as well as a significant inhibition of the modified DNA base formation (8-OH-dG) in both protocols. Marked suppression of aneuploidy occurred with treatment at 16 weeks in the initiation/promotion experiment. These findings, when combined with the proapoptotic property of these compounds and their ability to inhibit hydrogen peroxide (H(2)O(2)) generation, nuclear factor-kappaB (NF-kappaB) activation, and inducible nitric oxide synthase (iNOS) induction reported elsewhere, suggest that avicins could prove exciting in reducing oxidative and nitrosative stress and thereby suppressing the development of human skin cancer and other epithelial malignancies.  相似文献   
64.
Health promotion practice in health care has a high priority in the endeavour to achieve equal opportunities for health and diversity in health among the population. The purpose of the study was to investigate whether there is any connection between the lifestyle advice given by healthcare professionals and the lifestyle change of the population, focusing on age, gender and education level. The study is based on the data from a national population survey in Sweden in which 52 595 patients who had attended health care were interviewed by phone. The participants were asked whether healthcare professionals had raised the subject of lifestyle during the visit and whether the advice they gave had contributed to a lifestyle change. The results indicated that lifestyle issues were raised with 32.2% of those who attended health care, particularly among men, younger patients and those with a high education level. When lifestyle issues were raised, the advice contributed to 39.2% of patients making a lifestyle change, to a higher extent among men, older patients and those with a low education level. The study shows that lifestyle advice given by healthcare professionals, during both emergency and outpatient healthcare visits, is an important contributor to patients' lifestyle change.  相似文献   
65.
Aims and objectives. The aim of this study was to examine sense of coherence and experiences of change in social support and mastery from a short‐term perspective in patients who had been admitted to hospital with a suspected myocardial infarction. Background. The early discharge period after an acute cardiac event can be a stressful and vulnerable time when psychosocial resources are of the utmost importance. A positive outcome in an encounter with a stressor is thought to be linked to a strong sense of coherence, social support and mastery. Design. A multi‐centre survey was conducted in three hospitals in southern Sweden. Methods. The sample was 300, 241 of whom completed the questionnaires; while in hospital and two weeks postdischarge. Results. In the early discharge period a low sense of coherence was found in over 60% of the sample. There was an association between social support and mastery and between sense of coherence and mastery. Differences in social support ratings, with lower ratings two weeks postdischarge, were found among women and persons over 65 years of age. Conclusions. This study adds knowledge about experiences in the early discharge period. Changes in ratings of social support but not in ratings of mastery were found between baseline and two weeks postdischarge. Relevance to clinical practice. Healthcare professionals need to be sensitive to patients’ sense of coherence, mastery and need for social support during the early discharge period. They can help patients to identify adequate support strategies and prevent future potential complications. However, to routinely assess sense of coherence, social support and mastery, there is a need for a simple and useful instrument in clinical practice.  相似文献   
66.
Ebola hemorrhagic fever is an acute and often deadly disease caused by Ebola virus (EBOV). The possible intentional use of this virus against human populations has led to design of vaccines that could be incorporated into a national stockpile for biological threat reduction. We have evaluated the immunogenicity and efficacy of an EBOV vaccine candidate in which the viral surface glycoprotein is biomanufactured as a fusion to a monoclonal antibody that recognizes an epitope in glycoprotein, resulting in the production of Ebola immune complexes (EICs). Although antigen-antibody immune complexes are known to be efficiently processed and presented to immune effector cells, we found that codelivery of the EIC with Toll-like receptor agonists elicited a more robust antibody response in mice than did EIC alone. Among the compounds tested, polyinosinic:polycytidylic acid (PIC, a Toll-like receptor 3 agonist) was highly effective as an adjuvant agent. After vaccinating mice with EIC plus PIC, 80% of the animals were protected against a lethal challenge with live EBOV (30,000 LD(50) of mouse adapted virus). Surviving animals showed a mixed Th1/Th2 response to the antigen, suggesting this may be important for protection. Survival after vaccination with EIC plus PIC was statistically equivalent to that achieved with an alternative viral vector vaccine candidate reported in the literature. Because nonreplicating subunit vaccines offer the possibility of formulation for cost-effective, long-term storage in biothreat reduction repositories, EIC is an attractive option for public health defense measures.  相似文献   
67.
The spontaneous occurrence of protein AA-type of amyloidosis varies among animal species. As reactive AA-type of amyloidosis has never been detected in the blue fox, we obtained acute phase sera to search for amyloid-protective elements. The purified SAA fraction was characterized by mass and sequence analyses to disclose any unique domains in the amino acid sequence. The data revealed an SAA protein with heterogeneities in several positions, and showed the typical insertion between positions 69 and 70. By comparing the amino acid sequence with that from other mammals, no unique sequence could be observed. However, a C-terminal fragment of apolipoprotein A-I (ApoA-I) was found attached to the SAA. The amino acid sequence of the ApoA-I fragment revealed a partially blocked and ragged N-terminus. A comparison of the amino acid sequence of ApoA-I with that from the dog showed that the ApoA-I fragment started about position 190, had an intact C-terminus, and showed an identical sequence in all positions, except one. Based on the data, we suggest an interaction of the C-terminal fragment of ApoA-I with the SAA protein that inhibits the AA fibrillogenesis in the blue fox.  相似文献   
68.
BACKGROUND: Long QT syndrome (LQTS) is a hereditary cardiac arrhythmogenic disorder characterized by prolongation of the QT interval in the electrocardiogram, torsades de pointes arrhythmia, and syncopes and sudden death. LQTS is caused by mutations in ion channel genes. However, only in half of the families is it possible to identify mutations in one of the seven known LQTS genes, why further genetic heterogeneity is expected. The genes KCND2 and KCND3, encoding the alpha-subunits of the voltage-gated potassium channels Kv4.2 and Kv4.3 conducting the fast transient outward current (I(TO,f)) of the cardiac action potential (AP) in the myocardium, have been associated with prolongation of AP duration and QT prolongation in murine models. METHODS: KCND2 and KCND3 were examined for mutations using single-strand conformation polymorphism (SSCP) analysis in 43 unrelated LQTS patients, where mutations in the coding regions of known LQTS genes had been excluded. RESULTS: Seven single nucleotide polymorphismsm (SNPs) were found, two exonic SNPs in KCND2 and three exonic and two intronic in KCND3. None of the five exonic SNPs had coding effect. All seven SNPs are considered normal variants. CONCLUSION: The data suggest that mutations in KCND2 and KCND3 are not a frequent cause of long QT syndrome.  相似文献   
69.
Nitrate-based vasodilators (NBVs) are commonly used to treat multiple sequelae of atherosclerosis. A commonly used NBV, glyceryl trinitrate (GTN) is bioactivated by mitochondrial, class 2 aldehyde dehydrogenase (ALDH2). ALDH2 and other ALDHs are NAD(P)+-dependent enzymes critical to the detoxification of cytotoxic lipid-aldehydes elevated in atherosclerotic lesions, such as trans-4-hydroxy-2-nonenal (HNE). The GTN bioactivation step, however, inactivates ALDH2 and may alter the metabolism of these aldehydes. In this study, we tested the hypothesis that multiple ALDH enzymes are inhibited by different NBVs. ALDH2, ALDH3A, and ALDH5A were present in aorta with ALDH2 and ALDH3A localized to the smooth muscle layers. GTN (1 μM) inhibited ALDH2 activity (55±6% of control) and ablated ALDH3 activity. In contrast, isosorbide-2,5-dinitrate (ISDN, 1 μM) inhibited ALDH3 activity (1.1±0.4% of control) but did not inhibit ALDH2 activity even up to 50 μM ISDN. In homogenates of rat aorta, GTN (1 μM) inhibited the NAD+-dependent (41±5% of control) and NADP+-dependent (25±6% of control) detoxification of HNE. The inhibition of ALDH3A, but not ALDH2, could be prevented by the addition of dithiothreitol. These studies demonstrate that GTN and ISDN possess selectivity for ALDH inactivation with different mechanisms of inactivation.  相似文献   
70.
PURPOSE: To compare chest radiographic findings and circulating B-type natriuretic peptide (BNP) levels as an adjunct to clinical findings in the diagnosis of heart failure in patients presenting with acute dyspnea. METHODS: The diagnostic performance of radiographic evidence of cardiomegaly/redistribution and BNP levels > or =100 pg/mL as indicators of heart failure were assessed in 880 patients presenting with acute dyspnea to the emergency departments of five U.S. and two European teaching hospitals. BNP levels were determined by a rapid, point-of-care device. Two blinded cardiologists reviewed all clinical data and categorized patients as to whether they had acute heart failure (n = 447) or not (n = 433). RESULTS: Three-factor analyses showed that BNP levels > or =100 pg/mL contributed significantly to the prediction of heart failure over each of the radiographic indicators. In a multivariate logistic regression analysis, both BNP levels > or =100 pg/mL (odds ratio [OR] = 12.3; 95% confidence interval [CI]: 7.4 to 20.4) and radiographic findings of cardiomegaly (OR = 2.3; 95% CI: 1.4 to 3.7), cephalization (OR = 6.4; 95% CI: 3.3 to 12.5), and interstitial edema (OR = 7.0; 95% CI: 2.9 to 17.0) added significant, predictive information above historical and clinical predictors of heart failure. CONCLUSION: In patients presenting to the emergency department with acute dyspnea, BNP levels and chest radiographs provide complementary diagnostic information that may be useful in the early evaluation of heart failure.  相似文献   
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