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161.
Glycinebetaine has previously been shown to be effective at reducing leakage from liposomes which are frozen then thawed. This study involved the preparation of a series of N-modified betaines and the comparison of their cryoprotective activities with those of glycine, sarcosine, N,N-dimethylglycine and glycinebetaine. All the compounds investigated, with the exception of (dimethyloctylammonio)acetate, reduced the degree of leakage, after freezing and thawing, with additive concentrations up to 0.6 M. Reducing the degree of N-terminal methylation of glycinebetaine appeared to increase the leakage from liposomes at additive concentrations between 0.2 and 0.6 M. (Dimethylethylammonio)acetate, (dimethylisopropylammonio)acetate and (N,N,N',N'-tetramethylethylenediammonio)-N,N'-diacetate appeared to be no more effective than glycinebetaine, whereas improved protection was afforded by (triethylammonio)acetate and (diethylmethylammonio)acetate at most concentrations. This study demonstrates that the cryoprotective activity of glycinebetaine may be improved with modifications to the N-terminal.  相似文献   
162.
Studies have shown that students and the general population have little knowledge about nursing schools and the nursing profession. This study investigates the extent to which a sample of the population of Brazil is aware of the existence of nursing schools, and how they have obtained this information. Data were collected by telephone interviews. The sample consisted of 326 subjects whose telephone numbers were taken from the telephone book. Analysis showed that 73% of the subjects were aware of the existence of two nursing schools in the city; however, 65.03% did not know the names of these schools. Direct communication with friends and family, as well as indirect communication by television and advertising, were the sources of information mentioned by those questioned.  相似文献   
163.
AIM: An evolutionary concept analysis was undertaken to clarify the concept of self-management of type 1 diabetes in children and adolescents. BACKGROUND: Several problems exist in the literature on self-management of type 1 diabetes in children and adolescents. There is no uniform terminology and there is no uniform definition of the concept. Also, there is no differentiation in the literature between self-management of diabetes in children and adults. METHODS: Ninety-nine references were reviewed and analysed in the disciplines of nursing, medicine, and psychology. After separate analyses revealed no significant differences across disciplines, the analyses were combined to describe the attributes, antecedents, consequences, and surrogate and related concepts. RESULTS: The three essential attributes of the concept were identified as process, activities, and goals. Self-management of type 1 diabetes in children and adolescents is an active and proactive process; it is daily, lifelong, and flexible, and it involves shifting and shared responsibility for diabetes care tasks and decision-making between child and parent. It is a process that involves collaboration with health care providers. Self-management of type 1 diabetes in children and adolescents also consists of varied and many activities related to giving insulin, monitoring metabolic control, regulating diet and exercise, to name just a few. The concept also involves goals, which may differ from one parent/child dyad to another. A working definition of the concept is suggested. CONCLUSIONS: It is hoped that a more uniform definition of the concept will enable researchers to continue investigating antecedents and consequences of the concept in a way that allows for aggregating results.  相似文献   
164.
165.
Summary: We have been involved in developing a health-related quality-of-life model for use as an outcome measure in epilepsy. As part of the further development of this model, we have developed a measure of life fulfilment. This scale is based on methods previously described by Krupinski in 1980. The value of Krupinski's approach is the opportunity for patients to weight the numerous aspects of their quality of life and assess the discrepancy between their actual and desired circumstances. The life fulfilment scale has been shown to be reliable (α= 0.7) and valid. The scale is currently being applied to several clinical studies in epilepsy. We believe that the scale provides a valuable contribution to our health-related quality-of-life model.  相似文献   
166.
Nurses need to take advantage of multiple internships and fellowships to learn about and experience the daily work of making health policy in Washington, DC. This article lists several of the current programs available for nurses and other health professionals. These internships and fellowships are career-changing experiences. Additionally, new relationships will be built with other health professionals that nurses will be able to use for years to come. Finally, if one of the structured experiences doesn't fit the nurse's timeframe, there is always the possibility to create a special internship to meet the nurse's needs.  相似文献   
167.
We all work in a multigenerational workforce. With extremes in generations, skills are needed to foster understanding among staff. There are many myths and realities about the age-related generations. While there are challenges in working in a multigenerational workforce, the generational differences tend to be exaggerated while the similarities are overlooked. A better understanding of these generations allows us to prevent communication breakdown and to close the communication gaps where they exist, creating a unit of harmony rather that discontent.  相似文献   
168.
Guidelines recommend that patients with COPD are stratified arbitrarily by baseline severity (FEV1) to decide when to initiate combination treatment with a long-acting β2-agonist and an inhaled corticosteroid. Assessment of baseline FEV1 as a continuous variable may provide a more reliable prediction of treatment effects. Patients from a 1-year, parallel-group, randomized controlled trial comparing 50 μg salmeterol (Sal), 500 μg fluticasone propionate (FP), the combination (Sal/FP) and placebo, (bid), were categorized post hoc into FEV1 <50% and FEV1 ≥50% predicted subgroups (n=949/513 respectively). Treatment effects on clinical outcomes – lung function, exacerbations, health status, diary card symptoms, and adverse events – were investigated. Treatment responses based on a pre-specified analysis explored treatment differences by severity as a continuous variable. Lung function improved with active treatment irrespective of FEV1; Sal/FP had greatest effect. This improvement appeared additive in milder disease; synergistic in severe disease. Active therapy significantly reduced exacerbation rate in patients with FEV1 <50% predicted, not in milder disease. Health status and breathlessness improved with Sal/FP irrespective of baseline FEV1; adverse events were similar across subgroups. The spirometric response to Sal/FP varied with baseline FEV1, and clinical benefits were not restricted to patients with severe disease. These data have implications for COPD management decisions, suggesting that arbitrary stratifications of baseline severity are not necessarily indicative of treatment efficacy and that the benefits of assessing baseline severity as a continuous variable should be assessed in future trials.  相似文献   
169.
ABSTRACT: Background: Hands‐and‐knees positioning during labor has been recommended on the theory that gravity and buoyancy may promote fetal head rotation to the anterior position and reduce persistent back pain. A Cochrane review found insufficient evidence to support the effectiveness of this intervention during labor. The purpose of this study was to evaluate the effect of maternal hands‐and‐knees positioning on fetal head rotation from occipitoposterior to occipitoanterior position, persistent back pain, and other perinatal outcomes. Methods: Thirteen labor units in university‐affiliated hospitals participated in this multicenter randomized, controlled trial. Study participants were 147 women laboring with a fetus at ≥37 weeks’ gestation and confirmed by ultrasound to be in occipitoposterior position. Seventy women were randomized to the intervention group (hands‐and‐knees positioning for at least 30 minutes over a 1‐hour period during labor) and 77 to the control group (no hands‐and‐knees positioning). The primary outcome was occipitoanterior position determined by ultrasound following the 1‐hour study period and the secondary outcome was persistent back pain. Other outcomes included operative delivery, fetal head position at delivery, perineal trauma, Apgar scores, length of labor, and women's views with respect to positioning. Results: Women randomized to the intervention group had significant reductions in persistent back pain. Eleven women (16%) allocated to use hands‐and‐knees positioning had fetal heads in occipitoanterior position following the 1‐hour study period compared with 5 (7%) in the control group (relative risk 2.4; 95% CI 0.88–6.62; number needed to treat 11). Trends toward benefit for the intervention group were seen for several other outcomes, including operative delivery, fetal head position at delivery, 1‐minute Apgar scores, and time to delivery. Conclusions: Maternal hands‐and‐knees positioning during labor with a fetus in occipitoposterior position reduces persistent back pain and is acceptable to laboring women. Given this evidence, hands‐and‐knees positioning should be offered to women laboring with a fetus in occipitoposterior position in the first stage of labor to reduce persistent back pain. Although this study demonstrates trends toward improved birth outcomes, further trials are needed to determine if hands‐and‐knees positioning promotes fetal head rotation to occipitoanterior and reduces operative delivery. (BIRTH 32:4 December 2005)  相似文献   
170.
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