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91.
INTRODUCTION: Very little is known about clinical nurse specialists and nurse practitioners (advance practice nurses [APNs]) who practice in emergency care settings. The Advanced Practice Committee of the ENA sought to determine a profile of these individuals. METHODS: Surveys were distributed to all registrants at 2 ENA conferences and posted on the ENA Web site. This survey asked 17 questions concerning the demographic characteristics of the APN respondents (eg, education, experience, certification, state recognition, and practice area). The survey was completed by 166 APNs. RESULTS: APNs had considerable experience as ED registered nurses before becoming an APN. They obtained their APN education at the master's degree or post-master's degree level. State recognition was required for 89.2% of the APNs. The majority of APNs (61.4%) obtained their certification through the American Nurses Credentialing Center. Nurse practitioners were predominantly family nurse practitioners (43%), and clinical nurse specialists were either critical care clinical nurse specialists (8.9%) or had other certifications (5.9%). APNs provided services in both the main emergency department and the fast track (45.7%) and were relatively new to their role as an APN. DISCUSSION: Consistent with current educational and certification requirements, the vast majority of APNs held a master's degree. Although relatively new to their role as APNs in emergency care, they were nonetheless very experienced as ED registered nurses. The majority of APNs were certified, even though that is not required for practice in all states. Continued research is needed to identify the most effective utilization of APNs, document their contributions to patient care outcomes, and develop strategies to meet their educational and practice needs.  相似文献   
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The authors describe four cases in which obstructive sleep apnea complicated the course and treatment of mania. An association between weight gain, obstructive sleep apnea, and lithium treatment is also illustrated.  相似文献   
94.
Comparing Crow's schizophrenia model with the defect state and Huber's basic symptoms shows that this model is an oversimplification of the complex reality of schizophrenic outcomes. The concept of negative symptoms is undermined by several factors, such as differing definitions, other confounding cross-sectional variables (e.g., akinesia and depression), short follow-ups and lack of confirmation by factorial analysis. The longitudinal concept of a defect state, which has been used in long-term follow-up studies, includes enduring symptoms currently classified as positive and negative. Huber's conceptualization of basic symptoms describes prodromal and enduring residual symptoms of schizophrenia associated with structural brain abnormalities. The overlap and lack of equivalence of these concepts and the limited empirical evidence does not allow firm conclusions. New longitudinal studies using clinical, psychosocial, and neuropsychological measures are needed to understand the natural history and etiology of the defect state.The authors are affiliated with the Medical College of Pennsylvania/EPPI, Philadelphia, PA. William H. Wilson, M.D., is currently at Oregon Health Sciences University, Portland, OR.  相似文献   
95.
Forty patients with karyotypically proven Turner syndrome were prospectively studied using magnetic resonance imaging (MRI) and echocardiography in order to determine the frequency of cardiovascular anomalies and to assess the utility of both imaging modalities as methods for cardiovascular evaluation in Turner syndrome. Cardiovascular anomalies were found in 45% of patients. A high absolute prevalence of bicuspid aortic valve (17.5%) and aortic coarctation (12.5%) were observed relative to comparable series. Of clinically significant abnormalities, three of five aortic coarctations and four of five ascending aortic dilatations were solely MRI detected and not evident at echocardiographic examination. MRI is thus seen as a valuable adjunct to echocardiography in the cardiovascular evaluation of Turner syndrome patients. The usefulness of MRI primarily relates to its ability to provide excellent visualisation of the entire thoracic aorta where a large proportion of clinically significant anomalies occur in Turner syndrome.  相似文献   
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The oxygen-sensitive bioreductive binding of 2-nitroimidazoles labeled with fluorescent side chains has been used to stain hypoxic mammalian cells selectively. Several novel compounds were synthesized with a 1-substituent containing a fluorescent, bicyclic system having a bridgehead-nitrogen atom. Additional amine and secondary alcohol substituents were also included in the link between the fluorophor and the nitroimidazole to improve water solubility. Their ability to discriminate between hypoxic and oxic cells was compared by flow cytometric analysis. A wide range of cellular fluorescence and hypoxic-oxic differentials in fluorescence was observed when compounds with indolizine fluorophors were incubated with cells, and one such compound was considered suitable for further evaluation in vivo. Two compounds with bimane fluorophors gave very little cellular fluorescence when incubated with hypoxic cells.  相似文献   
98.
Many large vault or skull base tumours are best treated by wide surgical excision and primary reconstruction using a microvascular free tissue transfer (free flap). We report 23 patients who were reconstructed using free flaps, eight having been previously treated surgically elsewhere and seven of whom had recurrent disease after radiotherapy. There was one flap failure and a local recurrence rate of 16% (3/19). The outcome at a mean follow-up period of 29 months, was 19 patients alive and four deaths.  相似文献   
99.
Assessment of the human coronary circulation using a Doppler catheter   总被引:2,自引:0,他引:2  
Arteriographic estimates of stenosis severity can fail to reflect the impact of an individual stenosis on delivery of blood to the myocardium. Whether a coronary stenosis is truly flow-limiting can be determined by measuring hyperemic blood flow or coronary flow reserve; however, until recently, the tools needed to measure coronary flow reserve in humans--namely, a method of quantitating coronary blood flow in individual arteries and another method for producing maximal microvascular vasodilation--were not available. Over the last 8 years, our laboratory group has developed a catheter for measuring coronary blood flow velocity in humans, using the Doppler principle, and studied the effects of microvascular vasodilators. These studies have enabled us to measure coronary flow reserve in humans and to characterize some of the effects of focal and diffuse atherosclerosis on the coronary circulation. In addition, we have used flow reserve measurements in the diagnosis of microvascular dysfunction in patients with chest pain and normal coronary arteries and as a means of assessing noninvasive methods for detecting focal coronary artery disease.  相似文献   
100.
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