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101.
中下段颈椎的应力松弛特性及前、后路手术对其的影响   总被引:3,自引:1,他引:2  
目的 研究中下段颈椎的应力松弛特性,并评估椎间盘切除植骨术与椎板切开术对其影响。方法 6例新鲜尸体完整颈椎及手术后颈椎,在模拟生理状态下进行屈曲及伸展位的应力松弛实验。结果 在恒应变条件下,绘制术前及不同术式后的中下段颈椎的应力松弛函数及曲线;术后的中下段颈椎的应力和初始化应力比值G(t)比术前明显增大,前路椎间盘切除植骨术后的G(t)值比椎板切开术大,两者均有统计学意义。结论 在恒应变条件下,颈椎具有快速应力松弛敏感性,屈曲位比伸展位大。椎板成形术及颈椎前路椎间盘切除植骨术都使颈椎的应力松弛能力减弱,前路椎间盘切除植骨术的影响更大。  相似文献   
102.
Clinical practice guidelines have emerged as a reality for medical practitioners over the past 20 years. Although virtually all groups interested in the development of practice guidelines hope for improvements in patient care, secondary expectations vary widely among those using them. Their use in daily practice by physicians has met with resistance from barriers including concerns of “cookbook” medicine, a loss of autonomy, and increased professional liability. The recent experience of the ACR in addressing these challenges illustrates that physicians are receptive to steps perceived to mitigate the risks accompanying the use of guidelines as well as to efforts to increase their understanding of implementing guidelines in clinical practice. The experiences of other medical societies and an inventory of future trends reveal additional challenges associated with the use of practice guidelines, as third parties look to guidelines as points of reference for gauging the performance of health care providers.  相似文献   
103.
Background: Elder patients with acute coronary syndromes (ACS) are less likely to receive cardiac catheterization. The reasons for this are unclear.
Objectives: To assess whether elder patients who had a documented history of dementia, lived in extended care facilities, or had do not intubate–do not resuscitate (DNR-DNI) advance directives were less likely to receive cardiac catheterization, despite having ACS with high-risk features.
Methods: This was a medical record review conducted at an urban teaching hospital. DNR-DNI status before hospitalization, extended care facility (nursing home or assisted living) residence, and a previous diagnosis of dementia were obtained from the medical record. Patients 65 years and older who presented to the emergency department with acute myocardial infarction or with unstable angina with ST segment deviation were included. Univariate and multivariate logistic regression were performed, and odds ratios (ORs) were reported with their 95% confidence intervals (CIs).
Results: Of the 201 eligible patients, 66 (32.8%) patients did not undergo cardiac catheterization. In the univariate analysis, patients who had dementia, resided in extended care facilities, or were DNR-DNI were less likely to receive cardiac catheterization. Only extended care facility residence (OR, 0.18; 95% CI = 0.04 to 0.83) and DNR-DNI status (OR, 0.19; 95% CI = 0.04 to 0.92) remained significantly associated with decreased cardiac catheterization in the multivariate analysis.
Conclusions: Elder patients with ACS residing in extended care facilities or who are DNR-DNI are less likely to receive cardiac catheterization. Future studies concerning the quality of ACS care for elders should take these variables into account.  相似文献   
104.
MRI测量颈胸角在选择颈胸段脊柱手术入路中的临床应用   总被引:11,自引:8,他引:3  
目的 :探讨在颈胸段脊柱术前应结合患者的颈胸段MRI的个体特征和疾病情况 ,选择手术创伤最小的手术入路。方法 :共 76例患者 ,其中 2 6例为颈胸段脊柱损伤 ,35例为颈胸段脊柱肿瘤 ,脊髓型颈椎病 12例 ,以及 3例颈胸段椎板减压术后后凸畸形。男 4 7例 ,女 2 9例。平均年龄 4 5 5岁 ,年龄范围 19~ 6 5岁。同时抽取 95套颈胸段MRI片。作胸骨上切迹向后水平延长线和胸骨上切迹向后上方至C7T1椎间盘前缘中点的连线 ,测量两线之夹角 ,称为颈胸角 (cervicothoracicangle ,CTA)。结果 :CTA平均为 4 7 6 4°(范围 2 5°~ 73°)。大于此平均角度且病灶在胸骨切迹水平线以上时可考虑低位下颈椎入路 ,5 0例 ;CTA较小 ,且病灶范围广 ,或尚累及T3 、T4,可以考虑经胸骨柄入路 ,13例 ;病灶范围广泛 ,经全胸骨入路 3例 ;Ⅰ期或Ⅱ期前后联合入路 5例 ;经右侧肩胛下后外侧胸腔入路 5例。结论 :颈胸段脊柱手术应尽量选择低位下颈椎入路等创伤较小的入路 ,其次考虑经胸骨柄入路。长节段脊柱受累的患者才考虑经右侧肩胛下后外侧胸腔或经全胸骨等创伤较大的入路。术前可以结合患者的病灶累及范围和颈胸手术角等MRI影像学表现 ,从而利于选择最合适的手术入路 ,减少手术风险、手术创伤和并发症 ,利于患者早日康复  相似文献   
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106.
TOPIC: Psychological impact of adoption and resulting core issues for adopted children. PURPOSE: To raise awareness of the psychological impact of adoption. SOURCES: Published literature and personal observations. CONCLUSIONS: Adoption raises unique issues and challenges for the child and adoptive parents. Resolving the issues of adoption is a lifelong process. Through an awareness of the issues inherent in adoption, nurses and parents can use strategies that will enhance children's self-esteem and decrease their emotional vulnerability. Search terms: Adoption, intervention, loss, self-esteem, strategies  相似文献   
107.
A documentation system that facilitates accurate and complete recording is needed by every obstetric/neonatal nursing service. Developing an individualized system is a major undertaking. However, specific steps can be taken to ease the process. These steps are described, beginning with the assessment phase and concluding with evaluation.  相似文献   
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