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111.
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   
112.
We describe the clinical and pathological findings of the hemolytic uremic syndrome (HUS) in two children with human immunodeficiency virus (HIV) infection. Both patients presented with microangiopathic hemolytic anemia, thrombocytopenia, and subsequently developed renal failure. The diagnosis of HUS was confirmed by renal histopathology in both patients. None of these children presented with bloody diarrhea, evidence of circulating antibody response to Escherichia coli O157 lipopolysaccharide, or other known risk factors for HUS, except for the presence of HIV infection. Each patient was treated with intravenous plasma infusion and renal replacement therapy. Their clinical course was characterized by non-oliguria and lack of significant hypertension throughout the acute phase of the disease. Despite these favorable clinical parameters, both patients developed end-stage renal failure. The etiology of this atypical HUS characterized by poor renal survival remains unknown and the role of HIV infection in its pathogenesis, although possible, is unclear. Received March 5, 1996; received in revised form and accepted October 15, 1996  相似文献   
113.
Abstract Home visiting is a central, long-standing, and yet theoretically underdeveloped public health nursing process. The general aim of this study was to expand and refine a preliminary model of home visiting A stylized field research investigation was conducted in the area of maternal-child health with one nurse in a visiting nurse association in New England. A specific type of home visiting, identified as child focused, emerged, with phases labeled as surveying and designating; selling and scheduling; approaching the home and the visit; entering the home; gaining permission to ask questions and access the infant—starting with the mother's expressed concerns; making the caregiving judgment—asking questions and weighing and examining the infant; and ending the visit. "Haunting and telling" was an additional phase for certain visits. The nurse conducted child-focused home visiting in three patterns. The single pattern is described in this article. Potential maternal, child, interactive, and environmental consequences were identified, as were factors influencing the process of maternal-child home visiting. Social exchange theory emerged as useful in describing how the nurse initiated, maintained, and ended the home visiting process, and in describing attendant client consequences.  相似文献   
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115.
The objective of this study was to determine the frequency and significance of the MR findings of incomplete shell collapse for detecting implant rupture in a series of surgically removed breast prostheses. MR images of 86 breast implants in 44 patients were studied retrospectively and correlated with surgical findings at explanation. MR findings included (a) complete shell collapse (linguine sign), 21 implants; (b) incomplete shell collapse (subcapsular line sign, teardrop sign, and keyhole sign), 33 implants; (c) radial folds, 31 implants; and (d) normal, 1 implant. The subcapsular line sign was seen in 26 implants, the teardrop sign was seen in 27 implants, and the keyhole sign was seen in 23 implants. At surgery, 48 implants were found to be ruptured and 38 were intact. The MR findings of ruptured implants showed signs of incomplete collapse in 52% (n = 25), linguine sign in 44% (n = 21), and radial folds in 4% (n = 2). The linguine sign perfectly predicted implant rupture, but sensitivity was low. Findings of incomplete shell collapse improved sensitivity and negative predictive values, and the subcapsular line sign produced a significant incremental increase in predictive ability. MRI signs of incomplete shell collapse were more common than the linguine sign in ruptured implants and are significant contributors to the high sensitivity and negative predictive values of MRI for evaluating implant integrity.  相似文献   
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117.
This paper concerns the analysis of menstrual data; in particular, methodology to identify variables that contribute to the variability of menstrual cycles both within and between women. The basis for the proposed methodology is a parameterization of the mean length of a menstrual cycle conditional upon the past cycles and covariates. This approach accommodates the length-bias and censoring commonly found in menstrual data. Data from a longitudinal study of menstrual patterns and other variables among Lese women of the Ituri Forest, Zaire, illustrate the methodology. A small simulation illustrates the bias caused by incorrectly deleting the censored cycles.  相似文献   
118.
Very little is known regarding the mechanisms of action of angiotensin II (Ang II) or the consequences of Ang II-dependent hypertension in the cerebral circulation. We tested the hypothesis that Ang II produces constriction of cerebral arteries that is mediated by activation of AT1A receptors and Rho-kinase. Basilar arteries (baseline diameter approximately 130 microm) from mice were isolated, cannulated and pressurized to measure the vessel diameter. Angiotensin II was a potent constrictor in arteries from male, but not female, mice. Vasoconstriction in response to Ang II was prevented by an inhibitor of Rho-kinase (Y-27632) in control mice, and was reduced by approximately 85% in mice deficient in expression of AT1A receptors. We also examined the chronic effects of Ang II using a model of Ang II-dependent hypertension, mice which overexpress human renin (R+) and angiotensinogen (A+). Responses to the endothelium-dependent agonist acetylcholine were markedly impaired in R+A+ mice (P<0.01) compared with controls, but were restored to normal by a superoxide scavenger (PEG-SOD). A-23187 (another endothelium-dependent agonist) produced vasodilation in control mice, but no response or vasoconstriction in R+A+ mice. In contrast, dilation of the basilar artery in response to a NO donor (NONOate) was similar in R+A+ mice and controls. Thus, Ang II produces potent constriction of cerebral arteries via activation of AT1A receptors and Rho-kinase. There are marked gender differences in cerebral vascular responses to Ang II. Endothelial function is greatly impaired in a genetic model of Ang II-dependent hypertension via a mechanism that involves superoxide.  相似文献   
119.
Glucose catabolism of a vascular perfused rat hemidiaphragm was determined at rest and during stimulation of the phrenic nerve with trains of either 5 (T5) or 15 (T15) pulses (20 msec intervals) per second. Tissues were perfused and bathed in HEPES-buffered medium containing 11 mM D-[U-14C, 5-3H]glucose, equilibrated with 100% O2. Resting glucose catabolism via the Emden-Meyerhof pathway was indicated by a 3H2O production rate per hemidiaphragm of 1.45 +/- 0.07 mumol/h, of which 47% was recovered as [14C]lactate with the remainder assumed to be metabolised by mitochondria. During the first 30 min of T5 and T15 stimulation, peak isometric tension declined from an initial value of 105 +/- 8 g by 54% and 79%, respectively. The resulting peak tensions of 48 and 22 g remained constant for the next 60 min. These tensions were associated with linear rates of 3H2O production of 2.93 +/- 0.41 and 2.84 +/- 0.25 mumol/h. Stimulation by T5 and T15 increased mitochondrial metabolism of glucose by 64% and 95%, respectively, with no significant alterations in lactate formation from either exogenous or endogenous sources. The results suggest that the initial decline in tension is due to fatigue of the fast anaerobic myofibers; whereas, the sustained force beyond 30 min is attributable to the mitochondrial-rich slow myofibers.  相似文献   
120.
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