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101.
Why is there a left side underestimation in rod bisection?   总被引:4,自引:0,他引:4  
Subjects set the extremities of a horizontal rod to appear equidistant from a central reference point, with or without central fixation. On either side, the contrast (salience) of the rod against the background was high or low. Extents to the left were set smaller than those to the right, an effect (LSU) which was stronger with central fixation, indicating that both hemispatial and anatomical pathway factors contribute. Reduced salience on the left increased rather than decreased the LSU, indicating the importance of attentional factors.  相似文献   
102.
PURPOSE: We sought to report the outcome of secondary intraocular lens (IOL) implantation in children. METHODS: This was a retrospective case review. RESULTS: A total of 77 eyes were identified. An average age at secondary implantation was 7.8 +/- 5.0 years, whereas the average age at primary cataract surgery was 1.5 +/- 2.6 years. Average follow-up was 2.7 +/- 1.9 years. Thirty eyes received a hydrophobic acrylic IOL implantation whereas 47 eyes received a PMMA IOL. The sites of fixation for implanted IOLs were as follows: anterior-chamber (n = 6), sulcus (n = 42), in-the-bag (n = 14), optic-capture (n = 6), piggyback (n = 4), and sutured (n = 5). Complications included clinically significant decentration, 4 (5.2%); visual axis opacification, 4 (5.2%); dislocation of the IOL, 2 (2.6%); and pupillary capture requiring repositioning of IOL, 1 (1.3%). Clinically significant decentration requiring surgical intervention was noted only in eyes with sulcus-fixated foldable IOLs (28.6%; 4/14). None of the 29 eyes with sulcus-fixated PMMA IOL implantation developed decentration. All the decentrations were in an inferior direction and occurred in eyes of male patients (P = 0.03). Eyes with an axial length of >23 mm were 4 times more likely to develop decentration if implanted with a sulcus-fixated foldable IOL when compared with eyes measuring <23 mm (P = 0.03). Postoperative geometric mean visual acuity was significantly better than preoperative visual acuity (P < 0.001). CONCLUSION: Secondary IOL implantation can be safely achieved in pediatric eyes. In-the-bag fixation of foldable IOLs is associated with a low rate of complications. Foldable lenses appear to have a higher rate of decentration than PMMA lenses when placed in the sulcus in eyes of myopic male patients.  相似文献   
103.
Volume and outcome of coronary artery bypass graft surgery   总被引:1,自引:1,他引:0  
J M Wilson  P Menkhaus  B W Gustin 《JAMA》1987,257(18):2434-2435
  相似文献   
104.
M Ma  H Hu  F Kutlar  J B Wilson  T H Huisman 《Hemoglobin》1987,11(5):473-479
A slow-moving gamma chain variant was discovered in the cord blood of an infant born to parents of the Han nationality from Jiangsu. The variant, which migrated electrophoretically at alkaline pH between Hb A and Hb D, was characterized by an Asp----His substitution at gamma 73, while residues gamma 75 and gamma 136 were occupied by Ile and Ala, respectively. As the A gamma T-chain was also present, this baby has two types of abnormal gamma-chain. The variant was named Hb F-Xin-Su.  相似文献   
105.
Abstract: The development of a teaching package for nurse educators on drug and alcohol problems is described and the contents of its 16 modules outlined.  相似文献   
106.
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   
107.
108.
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   
109.
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   
110.
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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