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991.
Objective.To describe the clinical, radiological and MRI features of six atypical cases of histologically proven appendicular Ewing
sarcoma/ primitive neuroectodermal tumour (PNET). Design. Retrospective review of case notes and available imaging was carried out. Patients. Six patients (4 male, 2 female; mean age 27years, range 19–44 years), presenting over a 77-month period, were identified
from the Bone Tumour Register. All had unusual clinical and imaging features for Ewing sarcoma/PNET.
Results and conclusions. Four tumours were centred on the distal femoral metaphysis, one in the proximal tibial metaphysis and one in the distal
tibial metaphysis. Plain radiographs were available in four cases and showed minor cortical changes. MRI demonstrated a relatively
small, eccentrically located intraosseous component with a large, eccentric extraosseous component. Extension into the epiphysis
was seen in three cases and into the adjacent joint in two cases. Intraosseous ”skip” metastases were present in three cases.
The clinical and imaging features were atypical for conventional intraosseous Ewing sarcoma/PNET and the exact site of origin
(intraosseous, periosteal or soft-tissue) was unclear.
Received: 6 December 1999 Revision requested: 7 February 2000 Revision received: 20 July 2000 Accepted: 4 August 2000 相似文献
992.
Miller TW Clayton R Miller JM Bilyeu J Hunter J Kraus RF 《Child psychiatry and human development》2000,30(4):255-272
School violence in rural communities has gained considerable attention nationally. Examined are theoretical considerations involving escape theory, the risk and protective factors for school violence, case analyses of recent case studies, and discussion of recent school violence involving fatal injuries to others. Also discussed are diagnostic issues in understanding children who are at-risk for school violence and ways school violence maybe managed in the schools. Suggestions and recommendations including recommendations provided by the National School Safety Center for school personnel are offered, as are steps to be taken in creating a safe school environment. This information may be helpful to child psychiatry and clinical personnel who provide services to school aged children. 相似文献
993.
The use of an ambulatory, automatic sleep recording device (QUISI? Version 1.0) in the evaluation of primary snoring and obstructive sleep apnoea Electroencephalogram (EEG) evaluation with polysomnography (PSG) according to the Rechtschaffen & Kales (R&K) rules is time and cost consumptive, but ambulatory polygraphy systems do not allow EEG recording routinely. As a consequence, the number of sleep disordered events cannot be calculated exactly. QUISI is a one‐channel, self‐applicable ambulatory EEG recording device. The present study was designed as a prospective, non‐randomized clinical trial. This investigation evaluated the results of 40 patients with primary snoring and obstructive sleep apnoea measured with level 1 PSG and QUISI simultaneously. Fifteen patients (37.5%) were primary snorers with normal sleep profiles, whereas 25 patients (62.5%) suffered from obstructive sleep apnoea (OSA) with a Respiratory Disturbance Index (RDI) of 38.6 ± 23.8. The mean total sleeping time (TST) was underestimated by 4.5%, while Sleep Efficiency Index (SEI) was understimated by 4.6% by the QUISI device compared with PSG. The correlation between the QUISI and the PSG estimates for single sleep stages demonstrated only moderate correlation. The statistical significance for sleep stage 2 was r = 0.42, P = 0.002; for sleep stage 3/4, r = 0.31, P = 0.02; and for WAKE, r = 0.33, P = 0.01. Sleep stage 2 as well as sleep stage 3/4 were underestimated by QUISI substantially (difference: ?5.6% and ?10.3%), while WAKE was overestimated by QUISI to a larger amount (difference: +10.4%). Sensitivity and specificity of QUISI to recognize pathological sleep profiles compared with PSG/R&K were 0.92 and 0.96 respectively. QUISI is able to evaluate normal versus altered sleep profiles in patients with primary snoring and OSA. Comparing the quartile ranges, we found substantial differences between QUISI and PSG/R&K. QUISI gives an impression of sleep architecture and objective verification of a sleep disturbance in an ambulant setting but cannot replace the sleep laboratory‐based PSG. 相似文献
994.
Understanding Employee Awareness of Health Care Quality Information: How Can Employers Benefit?
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Objective. To analyze the factors associated with employee awareness of employer-disseminated quality information on providers.
Data Sources. Primary data were collected in 2002 on a stratified, random sample of 1,365 employees in 16 firms that are members of the Buyers Health Care Action Group (BHCAG) located in the Minneapolis–St. Paul region. An employer survey was also conducted to assess how employers communicated the quality information to employees.
Study Design. In 2001, BHCAG sponsored two programs for reporting provider quality. We specify employee awareness of the quality information to depend on factors that influence the benefits and costs of search. Factors influencing the benefits include age, sex, provider satisfaction, health status, job tenure, and Twin Cities tenure. Factors influencing search costs include employee income, education, and employer communication strategies. We estimate the model using bivariate probit analysis.
Data Collection. Employee data were collected by phone survey.
Principal Findings. Overall, the level of quality information awareness is low. However, employer communication strategies such as distributing booklets to all employees or making them available on request have a large effect on the probability of quality information awareness. Employee education and utilization of providers' services are also positively related to awareness.
Conclusions. This study is one of the first to investigate employee awareness of provider quality information. Given the direct implications for medical outcomes, one might anticipate higher rates of awareness regarding provider quality, relative to plan quality. However, we do not find empirical evidence to support this assertion. 相似文献
Data Sources. Primary data were collected in 2002 on a stratified, random sample of 1,365 employees in 16 firms that are members of the Buyers Health Care Action Group (BHCAG) located in the Minneapolis–St. Paul region. An employer survey was also conducted to assess how employers communicated the quality information to employees.
Study Design. In 2001, BHCAG sponsored two programs for reporting provider quality. We specify employee awareness of the quality information to depend on factors that influence the benefits and costs of search. Factors influencing the benefits include age, sex, provider satisfaction, health status, job tenure, and Twin Cities tenure. Factors influencing search costs include employee income, education, and employer communication strategies. We estimate the model using bivariate probit analysis.
Data Collection. Employee data were collected by phone survey.
Principal Findings. Overall, the level of quality information awareness is low. However, employer communication strategies such as distributing booklets to all employees or making them available on request have a large effect on the probability of quality information awareness. Employee education and utilization of providers' services are also positively related to awareness.
Conclusions. This study is one of the first to investigate employee awareness of provider quality information. Given the direct implications for medical outcomes, one might anticipate higher rates of awareness regarding provider quality, relative to plan quality. However, we do not find empirical evidence to support this assertion. 相似文献
995.
996.
Guy J. Ben‐Simon Miriam Peiss Tanuj Nakra Abraham Spierer 《Clinical & experimental optometry》2004,87(3):175-179
Background: The development of myopia is influenced by hereditary factors, environmental factors and geneenvironment interaction. Reading and near‐work activity are associated with myopia and myopic progression. This study sought to determine and compare the prevalence of reduced unaided vision and spectacle use among third grade Israeli students from three different educational settings. Method: A sample of 917 students (mean age 8.5 years, range seven to 10 years) was drawn from the three Israeli educational streams: secular, Orthodox and ultra‐Orthodox. Children in the ultra‐Orthodox education pathway begin studying at the age of three years and their daily reading involves sustained near work with increased accommodative effort accompanied by head‐rocking movements. Reduced distance vision was used to indicate the likely development of or an increase in the amount of myopia. Spectacle lenses were measured to determine the prevalence of myopia. Results: Of the 917 students studied, 103 (11.2 per cent) wore spectacles (14.2 per cent of the males and eight per cent of the females); 82.5 per cent of those who wore spectacles were myopic. Males from ultra‐Orthodox schools had the highest rate of reduced unaided vision (72.5 per cent) compared with males from secular schools (27.3 per cent), males from Orthodox schools (59.3 per cent) or with females from all three groups (average of 34.8 per cent, p < 0.0001, chi squared). Males had a higher rate of reduced unaided vision, especially in the Orthodox and ultra‐Orthodox schools. Conclusions: Our study suggests that Jewish ultra‐Orthodox males have a higher prevalence and degree of myopia. The study habits of young children, including exposure to prolonged near tasks, high accommodative demands and possibly optical defocus induced by body sway, may contribute to the development of myopia. 相似文献
997.
Véronique Duchêne Séverine Ferdinand Ingrid Filliol Jean Fran?ois Guégan Nalin Rastogi Christophe Sola 《Infection, genetics and evolution》2004,4(1):5-14
In order to compare phylogenetic methods and to reconstruct the evolutionary history of the tubercle bacilli, a set of macro-array-based genotyping data of Mycobacterium tuberculosis clinical isolates (called spoligotyping for spacer oligonucleotide typing, which assays the variability of the Direct Repeat -DR- locus), was analyzed in four settings of the Caribbean region (Guadeloupe, Martinique, Cuba and Haiti). A set of 47 alleles, split into 26 shared and 21 unique alleles) representative of 321 individual M. tuberculosis clinical isolates from patients residing in the above regions was studied. The following methods (and software in brackets) were investigated: numerical taxonomy distance methods (TAXOTRON), maximum parsimony procedure (PAUP), median-joining networks (NETWORK), and nested clade analysis (GEODIS). Results using these methods were analyzed, compared and discussed. The latter method (GEODIS) was investigated in detail by introducing geographical data together with genetic variability results to detect a link between population structure and population history, and to test the null hypothesis of no association between geography and genotypes. Irrespective of the methods used, our findings demonstrate that a core structure of four families (or clades) of M. tuberculosis strains is highly prevalent within the islands studied, indirectly reflecting passed colonization history of these different settings. Specificity of M. tuberculosis genotypes in each of the islands is discussed in the light of their respective colonial and contemporary histories. 相似文献
998.
A.A. Orabi D. Mawman F. Al‐Zoubi S.R. Saeed R.T. Ramsden 《Clinical otolaryngology》2006,31(2):116-122
Objectives: To objectively evaluate the clinical and functional outcomes of cochlear implantation in an elderly population. Design: Retrospective comparative study. Setting: Neurotology unit at Manchester Royal Infirmary, a supraregional tertiary referral centre in collaboration with Adult Cochlear Implant Programme at The University of Manchester. Participants: All cochlear implant procedures (38) undertaken on post‐lingually deafened elderly patients (age range at the time of implantation 65–80 years, n = 34) in the period from 1989 to 2002. Main outcome measures: Medical and surgical outcomes. Audiological performance outcomes for isolated words, words in sentences in quiet and noise. Functional outcome measures used are self‐reported measures of the social, psychological and emotional aspects of quality of life, and the differences between expectations for functional outcomes and the realization of functional outcomes. They included expectation profiles, Glasgow Benefit inventory (GBI) and Glasgow Health Status Inventory Questionnaire (GHSI). Results: There was statistically significant improvement post‐implantation of both open and closed set test scores (P < 0.01). Eighty‐two percentage of patients were completely satisfied with their cochlear implants. Patients judged that implantation restored half the loss of quality of life that they had experienced as a result of severe‐profound deafness with a highly significant (P < 0.001) improvement in overall quality of life after implantation. The commonest post‐operative observation was transient mild pyrexia. Conclusions: The age of a cochlear implant candidate should not be a factor in the candidacy decision‐making process. The quality of life of our elderly recipients was significantly improved after cochlear implant. 相似文献
999.
1000.