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41.
In Western society, policy and legislation seeks to minimize restrictive interventions, including physical restraint; yet research suggests the use of such practices continues to raise concerns. Whilst international agreement has sought to define physical restraint, diversity in the way in which countries use restraint remains disparate. Research to date has reported on statistics regarding restraint, how and why it is used, and staff and service user perspectives about its use. However, there is limited evidence directly exploring the physical and psychological harm restraint may cause to people being cared for within mental health inpatient settings. This study reports on an integrative review of the literature exploring available evidence regarding the physical and psychological impact of restraint. The review included both experimental and nonexperimental research papers, using Cooper's (1998) five‐stage approach to synthesize the findings. Eight themes emerged: Trauma/retraumatization; Distress; Fear; Feeling ignored; Control; Power; Calm; and Dehumanizing conditions. In conclusion, whilst further research is required regarding the physical and psychological implications of physical restraint in mental health settings, mental health nurses are in a prime position to use their skills and knowledge to address the issues identified to eradicate the use of restraint and better meet the needs of those experiencing mental illness.  相似文献   
42.
OBJECTIVE: Cigarette smoking is associated with increased plasma homocysteine concentrations, endothelial dysfunction and arterial stiffening. Homocysteine per se induces endothelial dysfunction and arterial stiffening and might account, at least partly, for the vascular abnormalities observed in smokers. We sought to determine whether folic acid supplementation, by reducing plasma homocysteine concentrations, enhanced endothelial function and reduced arterial stiffness in smokers. DESIGN: Double-blind, randomized controlled, parallel-group, trial. SETTING: Academic medical centre. SUBJECTS: A consecutive sample of 24 healthy cigarette smokers (age 37.8 +/- 2.5 years, mean +/- SEM). INTERVENTION: Subjects were randomly assigned to 4-week folic acid 5 mg day-1 or placebo. MAIN OUTCOME MEASURES: The following were measured before and after treatment: (i) peripheral vasoreactivity (forearm arterial blood flow, FABF) during intra-arterial administration of endothelium-dependent (acetylcholine 1.5, 4.5 and 15 microg min-1) and endothelium-independent (sodium nitroprusside 1, 2 and 4 microg min-1) vasodilators; (ii) carotid-femoral pulse-wave velocity (PWV); (iii) blood pressure (BP). RESULTS: Folic acid reduced homocysteine concentrations (10.8 +/- 0.6 vs. 8.2 +/- 0.5 micromol L-1, P < 0.001) and enhanced endothelium-dependent vasodilatation during each acetylcholine infusion rate (ratio between the FABF in the infused and control arm during increasing infusion rates at baseline 1.09 +/- 0.03 vs. 1.41 +/- 0.09 after treatment, P < 0.01; 1.39 +/- 0.07 vs. 1.83 +/- 0.12, P < 0.01; 1.65 +/- 0.16 vs. 2.72 +/- 0.36, P < 0.05) whilst endothelium-independent vasodilatation was unaffected. A significant fall in BP was also observed (mean BP 88 +/- 2 vs. 83 +/- 1 mmHg, P < 0.01). By contrast, PWV did not significantly change (8.4 +/- 0.3 vs. 7.8 +/- 0.4 m s-1). No significant changes in plasma homocysteine concentrations, FABF, BP, and PWV were observed in the placebo group. A multiple regression analysis showed that changes in folic acid plasma concentrations independently predicted both FABF changes during maximal acetylcholine-mediated vasodilatation (P < 0.01) and BP changes (P = 0.01). CONCLUSIONS: Short-term folic acid supplementation significantly enhanced endothelial function and reduced BP in young chronic smokers. These effects were largely independent from the homocysteine lowering effects. Thus, a simple, nontoxic, and relatively inexpensive vitamin intervention might be useful in primary cardiovascular prevention in this high-risk group.  相似文献   
43.
T A Swift  J A Dias 《Endocrinology》1987,120(1):394-400
Sertoli cells derived from 21-day-old rats were cultured in serum-free Ham's F-10 medium to allow a direct investigation of the effects of FSH on polyamine (PA) biosynthesis in a defined culture system. After 48 h in culture, the basal cellular content consisted predominantly of spermine (1.1 nmol/mg protein) with substantially lower amounts of spermidine (0.1 nmol/mg protein) and undetectable amounts of putrescine. Upon the addition of ovine FSH (3 X 10(-9) M), cellular spermine content became significantly elevated above the control value as early as 1 h after treatment, reaching a 2.5-fold stimulation by 4 h. Spermidine was also elevated by 4 h after FSH treatment, but remained less than 20% of the spermine concentration. At no time did the cellular content of putrescine increase to measurable levels. Extended time-course studies demonstrated that the FSH-induced cellular increase in spermine and spermidine content persisted up to 24 h during the continuous presence of FSH. Bu2cAMP (5 mM) invoked similar changes in PA levels when measured at 4, 8, and 24 h. Ornithine decarboxylase (ODC) activity, which catalyzes the production of putrescine, was increased by FSH in a temporal fashion similar to that of spermine production. Addition of alpha-difluoromethylornithine, an irreversible inhibitor of ODC, blocked increases in both ODC activity and PA in cells stimulated with FSH or Bu2cAMP. Pulse-chase experiments using [3H]ornithine demonstrate that putrescine is initially synthesized, and is subsequently converted to spermidine and spermine. These studies suggest that regulation of PA biosynthesis by FSH is largely expressed as increases in spermine, and to a lesser extent spermidine, suggesting that the more complex PAs may be involved in the regulation of Sertoli cell function.  相似文献   
44.
To evaluate the potential for hyperbaric oxygen (HBO) to produce transient improvement in function in areas of myocardium ischemic at rest (hibernating myocardium), 24 patients were studied within 1 week of acute myocardial infarction. Results were compared with single-photon emission computed tomography (SPECT) thallium-201 exercise scintigraphy. Echocardiography demonstrated improved contraction following HBO in 20 of 62 damaged left ventricular segments in 12 of 24 patients. Thirteen of the 28 segments and 9 of the 14 patients showing reversible ischemia on SPECT imaging showed improvement with HBO. There were eight segments with apparently normal resting contraction that showed a reversible thallium defect. Of 42 segments with fixed contraction abnormalities following HBO, eight had reversible thallium defects, four had normal thallium kinetics, and 30 had fixed thallium defects. Thus hyperbaric oxygen can demonstrate improvement in function in some segments of left ventricle after infarction. There is some overlap with viability as determined by thallium studies, but the two techniques may be complementary in describing myocardial ischemia.  相似文献   
45.
Clayton H  Turner J  Swift S  James R  Bell P 《Pancreas》2001,22(1):72-74
Recent reports suggest that apoptosis resulting from the disruption of the normal cell-matrix relationship (anoikis) during islet isolation could lead to a loss of islet tissue in culture. Insulin is known to have a role in cell growth and survival, and this study was undertaken to assess any beneficial effect on islets by supplementing the islet culture medium with insulin. Human and porcine islets were cultured in medium supplemented with 0, 10, 100, and 1,000 ng x mL(-1) insulin. Secretory function was assessed by perifusion at days 1 and 8. The results demonstrated a significant variation in stimulation index between isolations for human islets, but there was no effect relating to the concentration of insulin in the medium or time in culture. For porcine islets, there was a significant (p < 0.001) improvement in secretory function for islets cultured in 10 and 100 ng x mL(-1) insulin, relative to 0 and 1,000 ng x mL(-1) insulin. There was no interisolation variation or effect of time in culture. In conclusion, the secretory function of porcine islets benefited from the addition of 10 to 100 ng x mL(-1) insulin to the culture medium, but interisolation variation in human islet secretory function did not allow any specific effect of the insulin to be determined.  相似文献   
46.
47.
Patients with severe aplastic anemia (SAA) and a neutrophil (PMN) count of less than 0.5 x 10(9)/L are exposed to a high risk of early mortality when treated with antilymphocyte globulin (ALG) and steroids, with the major problem being infectious complications. The addition of human recombinant granulocyte colony-stimulating factor (rhG-CSF) to ALG may reduce early mortality by improving neutrophil counts in the short term. To test the feasibility of this approach, the SAA Working Party of the European Group for Blood and Marrow Transplantation (EBMT) designed a pilot study that included rhG-CSF (5 micrograms/kg/d, days 1 through 90), horse ALG (HALG; 15 mg/kg/d, days 1 through 5), methylprednisolone (2 mg/kg/d, days 1 through 5, then tapering the dose), and cyclosporin A (CyA; 5 mg/kg/d orally, days 1 through 180). Patients with newly diagnosed acquired SAA (untreated) and with neutrophil counts of < or = 0.5 x 10(9)/L were eligible. Forty consecutive patients entered this study and are evaluable with a minimum follow up of 120 days: the median age was 16 years (range, 2 to 72 years), the interval from diagnosis to treatment was 24 days, and the median PMN count was 0.19 x 10(9)/L. Twenty-one patients had hemorrhages, and 19 were infected at the time of treatment. Overall, treatment was well tolerated: the median maximum PMN count during rhG- CSF administration was 12 x 10(9)/L (range, 0.4 x 10(9)/L to 44 x 10(9)/L). There were three early deaths (8%) due to infection. Four patients (10%) showed no recovery, whereas 33 patients (82%) had trilineage hematologic reconstitution and became transfusion- independent at a median interval of 115 days from treatment. Median follow up for surviving patients is 428 days (range, 122 to 1,005). Actuarial survival is 92%: 86% and 100% for patients with PMN counts less than 0.2 x 10(9)/L or between 0.2 x 10(9)/L and 0.5 x 10(9)/L, respectively. This study suggests that the addition of rhG-CSF to ALG and CyA is well tolerated, is associated with a low risk of mortality, and offers a good chance of hematologic response. This protocol would appear to be an interesting alternative treatment for SAA patients with a low PMN count who lack an HLA-identical sibling.  相似文献   
48.
49.
Background: Despite advances in developing medications to treat alcohol dependence, few such medications have been approved by the Food and Drug Administration. Identified molecular targets are encouraging and can lead to the development and testing of new compounds. Atypical antipsychotic medications have been explored with varying results. Prior research suggests that the antipsychotic quetiapine may be beneficial in an alcohol‐dependent population of very heavy drinkers. Methods: In this double‐blind, placebo‐controlled trial, 224 alcohol‐dependent patients who reported very heavy drinking were recruited across 5 clinical sites. Patients received either quetiapine or placebo and Medical Management behavioral intervention. Patients were stratified on gender, clinical site, and reduction in drinking prior to randomization. Results: No differences between the quetiapine and placebo groups were detected in the primary outcome, percentage heavy‐drinking days, or other drinking outcomes. Quetiapine significantly reduced depressive symptoms and improved sleep but had no effect on other nondrinking outcomes. Results from a subgroup analysis suggest that patients who reduced their drinking prior to randomization had significantly better drinking outcomes during the maintenance phase (p < 0.0001). No significant interactions, however, were observed between reducer status and treatment group. Finally, quetiapine was generally well tolerated. Statistically significant adverse events that were more common with quetiapine versus placebo include dizziness (14 vs. 4%), dry mouth (32 vs. 9%), dyspepsia (13 vs. 2%), increased appetite (11 vs. 1%), sedation (15 vs. 3%), and somnolence (34 vs. 9%). Conclusions: This multisite clinical trial showed no efficacy for quetiapine compared with placebo at reducing alcohol consumption in heavy‐drinking alcohol‐dependent patients.  相似文献   
50.
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