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31.
Aims and objectives.  The proposed model of event-generated dependence characterizes dependence in older adults as an emergent phenomenon that may arise from interaction between the older adult with compromised health and the social environment, resulting in altered reciprocity.
Background.  Pejorative characterizations of dependence in older adults influence nursing care negatively. Concept analyses recommend the recognition that dependence is interactive in nature, not an inherent trait of the individual, and that dependence involves changes in interpersonal reciprocity.
Conclusions.  The model provides a testable causal path between dependence and psychological outcomes.
Relevance to clinical practice.  The event generated dependence model can sensitize nurses to an alternative view of dependence. It is important for nurses to recognize their role in determining the social environment of care, attend to the promotion of reciprocity with older adults as care is provided, and incorporate changes in their attitudes toward inequitable reciprocity.  相似文献   
32.
Many nursing studies on moral reasoning and ethics have used Kohlberg's theory of moral development. The body of knowledge that resulted from these studies indicated that nurses and nursing students had consistently lower than expected levels of moral reasoning. Educational offerings were developed to assist nurses to improve their moral reasoning. This article explores the cognitive-developmental theory of moral development as one way of determining the moral development of nurses. Since this theory of moral reasoning focuses on the rational thought of the individual and does not consider the impact of the environment, it is of limited applicability in nursing. A new theory of morality needs to be developed—a more holistic one that will include both universal principles and contextual issues.  相似文献   
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OBJECTIVE: To examine the acute glucose-lowering effects of aerobic exercise in children and adolescents with type 1 diabetes. RESEARCH DESIGN AND METHODS: Fifty children and adolescents with type 1 diabetes (ages 10 to <18 years) were studied during exercise. The 75-min exercise session consisted of four 15-min periods of walking on a treadmill to a target heart rate of 140 bpm and three 5-min rest periods. Blood glucose and plasma glucagon, cortisol, growth hormone, and norepinephrine concentrations were measured before, during, and after exercise. RESULTS: In most subjects (83%), plasma glucose concentration dropped at least 25% from baseline, and 15 (30%) subjects became hypoglycemic (< or = 60 mg/dl) or were treated for low glucose either during or immediately following the exercise session. The incidence of hypoglycemia and/or treatment for low glucose varied significantly by baseline glucose, occurring in 86 vs. 13 vs. 6% of subjects with baseline values <120, 120-180, and >180 mg/dl, respectively (P < 0.001). Exercise-induced increases in growth hormone and norepinephrine concentrations were marginally higher in subjects whose glucose dropped < or = 70 mg/dl. Treatment of hypoglycemia with 15 g of oral glucose resulted in only about a 20-mg/dl rise in glucose concentrations. CONCLUSIONS: In youth with type 1 diabetes, prolonged moderate aerobic exercise results in a consistent reduction in plasma glucose and the frequent occurrence of hypoglycemia when preexercise glucose concentrations are <120 mg/dl. Moreover, treatment with 15 g of oral glucose is often insufficient to reliably treat hypoglycemia during exercise in these youngsters.  相似文献   
35.
: Ventilatory support in neonatal intensive care units (NICU) and related care modalities have profound lifelong benefits for neonates. : Ventilatory support and predictors of hospital stay were prospectively examined in 262 neonates and their mothers who were admitted to a NICU. A mixed-model, generalized estimating equation approach was used for prediction analysis, accounting for the dependencies of multiple births (26.3% of sample). : Predictors for hospital stay included gestational age, congenital defects, birth weight, days requiring ventilator support, and oxygen support. Cubic curves present the best-fit model for the relationships between maturity (gestational age and birth weight) and length of hospital stay; along with days requiring oxygen support, ventilator support, and central arterial and venous access lines. : Ventilatory support and associated care modalities are important resources for high-risk neonates during hospital stay. Future studies need to determine the best care course for neonatal ventilatory support to prevent complications.  相似文献   
36.
Medical applications of transforming growth factor-beta   总被引:11,自引:0,他引:11       下载免费PDF全文
Transforming growth factor-beta (TGF-beta) proteins and their antagonists have entered clinical trials. These multi-functional regulators of cell growth and differentiation induce extracellular matrix proteins and suppress the immune system making TGF-betas useful in treatment of wounds with impaired healing, mucositis, fractures, ischemia-reperfusion injuries, and autoimmune disease. In diseases such as keloids, glomerulonephritis and pulmonary fibrosis, excessive expression of TGF-beta has been implicated as being responsible for accumulation of detrimental scar tissue. In these conditions, agents that block TGF-beta have prevented or reversed disease. Similarly, in carcinogenesis, blocking TGF-beta activity may be valuable in stimulating an immune response towards metastasis. As these blocking agents receive approval, we will likely have new therapies for previously recalcitrant diseases.  相似文献   
37.
Signs of physical dependence as a consequence of long-term drug use and a moderate abuse liability limit benzodiazepine clinical usefulness. Growing evidence suggests a role for voltage-gated calcium channel (VGCC) regulation in mediating a range of chronic drug effects from drug withdrawal phenomena to dependence on a variety of drugs of abuse. High voltage-activated (HVA) calcium currents were measured in whole-cell recordings from acutely isolated hippocampal CA1 neurons after a 1-week flurazepam (FZP) treatment that results in withdrawal-anxiety. An approximately 1.8-fold increase in Ca(2+) current density was detected immediately after and up to 2 days but not 3 or 4 days after drug withdrawal. Current density was unchanged after acute desalkyl-FZP treatment. A significant negative shift of the half-maximal potential of activation of HVA currents was also observed but steady-state inactivation remained unchanged. FZP and diazepam showed use- and concentration-dependent inhibition of Ca(2+) currents in hippocampal cultured cells following depolarizing trains (FZP, IC(50) = 1.8 microM; diazepam, IC(50) = 36 microM), pointing to an additional mechanism by which benzodiazepines modulate HVA Ca(2+) channels. Systemic preinjection of nimodipine (10 mg/kg), an L-type (L)-VGCC antagonist, prevented the benzodiazepine-induced increase in alpha-amino-3-hydroxy-5-methylisoxasole-4-propionic acid receptor (AMPAR)-mediated miniature excitatory postsynaptic current in CA1 neurons 2 days after FZP withdrawal, suggesting that AMPAR potentiation, previously linked to withdrawal-anxiety may require enhanced L-VGCC-mediated Ca(2+) influx. Taken together with prior work, these findings suggest that enhanced Ca(2+) entry through HVA Ca(2+) channels may contribute to hippocampal AMPAR plasticity and serve as a potential mechanism underlying benzodiazepine physical dependence.  相似文献   
38.
Introduction: Pain is the most common symptom in patients presenting for prehospital (PH) care. Research in civilian emergency medical systems has shown wide variability in PH pain assessment and analgesic practices, yet a minimal amount is known about pain assessment and analgesic intervention practices in the military, particularly when PH care is delivered in a combat zone. Objective: To describe prehospital (PH) pain care practices for U.S. military personnel injured in Iraq and Afghanistan 2010–2013 and explore potential relationships to explain variation. Methods: An exploratory retrospective, cross-sectional study of Department of Defense Trauma Registry data from 2010 to 2013 was performed. Demographic, clinical, or health system variables for associations with three outcomes: 1) pain assessment documentation; 2) pain severity (0–10 scale); and 3) analgesic administration (yes/no). Including only variables with significant associations, backward stepwise regression was used to develop explanatory models for each outcome. Results: Patient records (n = 3,317) were evaluated for documentation of PH pain assessment and analgesic administration. The prevalence of PH pain score documentation was 37.8% (n = 1,253). Overall, the proportion of records with PH pain scores increased over time: 19.8% (2010), 35.1% (2011), 58.2% (2012), and 62.2% (2013). Severity of pain scores ranged 0–10; mean = 5.5 (SD = 3.1); median = 6 (IQR = 3–8). Analgesics were reported for 50.8% (n = 1,684), of whom 38.3% had a pain severity score documented. The pain assessment documentation model included any documented vital signs, injury year, and mechanism of injury and explained 19.3% of the variance in documentation. The pain severity model included vital signs and injury severity score (ISS) and explained 5.0% of the variance in severity. The analgesic model included any vital signs, pain severity, trauma type, mechanism of injury, ISS, and year. Conclusions: Pain assessment and treatment documentation improved each year, but remain suboptimal. Available data yielded poor prediction of the outcomes of interest, emphasizing the importance of individual assessment. Analgesic effectiveness could not be evaluated.  相似文献   
39.
A severe nursing shortage has the profession in crisis. The national picture is paralleled in Oregon. The Oregon Nursing Leadership Council (ONLC), through intense dialogue, developed a comprehensive statewide plan to resolve the shortage. From the perspective of group relations and leadership theories, this article describes the issues and events that contributed to the remarkable journey that culminated in this plan. Motivated by our concern for the public welfare and the survival of our profession, individual ONLC members surrendered their own narrow organizational goals to achieve a more effective collective outcome.  相似文献   
40.
Objective: To determine whether a skills laboratory for corneal foreign body and rust ring removal improves self-assessed skill and confidence.
Methods: A prospective trial was conducted as part of the didactic curriculum of a university-based residency program in emergency medicine (EM). A convenience sample of 26 EM residents and five fourth-year medical students participated. The skills laboratory used model corneas made by coating 3.2-cm glass spheres with a 1–2-mm film of paraffin. Foreign bodies were simulated by embedding small pieces of metal into the paraffin. Rust rings were simulated by dipping a hot, straightened paper clip into a rust-colored crayon and then into the paraffin. The model eyes fit into a life-sized model of a human head. Participants removed the foreign bodies and rust rings under supervision, using the slit lamp. Each participant anonymously completed a questionnaire before and after participating in the skills laboratory. The questionnaire recorded educational level, previous experience, and self-assessed comfort and skill levels (0 = lowest, 10 = highest).
Results: Most (66%) of the participants had not previously removed a corneal foreign body; 86% had not previously removed a rust ring. On a ten-point scale, the median comfort level for removing a foreign body rose from 2 to 7, and the self-assessed skill level rose from 1 to 7 (p = 0.0001). Similar improvements in self-assessed comfort and skill levels were seen for rust ring removal.
Conclusions: Participation in this skills laboratory significantly improved the self-reported comfort and self-assessed skill levels in removing corneal foreign bodies and rust rings. This technique provides useful practice of a fine-motor procedural skill requiring eye-hand coordination prior to supervised application of these skills in clinical practice.  相似文献   
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