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41.
An anomalous pulmonary vein draining into the subdiaphragmatic inferior vena cava was initially demonstrated on computed tomographic (CT) scans. The diagnosis of scimitar syndrome was confirmed with digital subtraction angiography. In retrospect, the anomalous vein and dextroposition of the heart were shown on chest radiographs. 相似文献
42.
Hepatic resection in the United States: indications,outcomes, and hospital procedural volumes from a nationally representative database 总被引:22,自引:0,他引:22
Dimick JB Cowan JA Knol JA Upchurch GR 《Archives of surgery (Chicago, Ill. : 1960)》2003,138(2):185-191
BACKGROUND: Hepatic resection has become common in the United States for both primary and secondary hepatic tumors. HYPOTHESIS: Variation in outcomes after hepatic resection is related to patient characteristics, the indication for operation, and hospital procedural volume. DESIGN: Observational study using a nationally representative database. PATIENTS: All patients in the Nationwide Inpatient Sample for 1996 and 1997 with a primary procedure code for hepatic resection (N = 2097). MAIN OUTCOME MEASURES: Outcomes included in-hospital mortality and length of stay. Risk-adjusted analyses were performed using hierarchical multivariate models. RESULTS: Overall mortality for the 2097 patients was 5.8%. The most common indications for hepatic resection were secondary metastases (52%), primary hepatic malignancy (16%), biliary tract malignancy (10%), and benign hepatic tumor (5%). High-volume hospitals had a mortality rate of 3.9% vs 7.6% at low-volume hospitals (P<.001). In the multivariate analysis adjusting for patient case-mix, high-volume hospitals had a 40% lower risk of in-hospital mortality compared with low-volume hospitals (odds ratio, 0.60; 95% confidence interval, 0.39-0.92; P =.02). Other predictors of mortality in the multivariate analysis included age older than 65 years, hepatic lobectomy (vs wedge resection), primary hepatic malignancy (vs metastases), and the severity of underlying liver disease. CONCLUSIONS: Hospital procedural volume is an important predictor of mortality after hepatic resection. Patients who require resection of primary and secondary liver tumors should be offered referral to a high-volume center. 相似文献
43.
Eosinophil autofluorescence and its use in isolation and analysis of human eosinophils using flow microfluorometry 总被引:5,自引:1,他引:5
Unstained human eosinophils exhibit unusually bright autofluorescence, which allows them to be distinguished from other leukocytes using fluorescence microscopy. Eosinophil fluorescence is associated with the cytoplasmic granules of the cells. Eosinophil granule extracts, containing an as-yet-undefined eosinophil fluorescence factor, exhibited excitation maxima at 370 nm and 450 nm, with maximum emission at 520 nm. Eosinophils adhering to opsonized parasites in vitro deposit fluorescent material onto the parasite surface. Eosinophil fluorescence was of sufficient intensity to allow the preparation of viable, highly enriched (greater than or equal to 98%), eosinophil suspensions from peripheral blood of normal and eosinophilic donors using a fluorescence- activated cell sorter. Quantitative studies of eosinophil autofluorescence were performed using flow microfluorometry. Fluorescence intensity of blood eosinophils from normal volunteers and eosinophilic patients varied inversely with the log of the donor's absolute eosinophil count regardless of clinical diagnosis. 相似文献
44.
W. M. C. van Aalderen D. S. Postma G. H. Koëter J. Gerritsen K. Knol 《Inflammation research》1990,30(1-2):258-260
In a study of two groups of nine allergic asthmatic children, consisting of one group with (group I) and one group without (group II) increased nocturnal airflow obstruction, we determined whether an increase in vagal activity, or inflammatory mediators like histamine are responsible for the nocturnal increase in airflow obstruction. The results of investigations in the two groups of asthmatics were compared to the results of an age matched control group. Forced expiratory volume in one second (FEV1) and electrocardiogram recordings of one minute were obtained every 4 hours during 24 hours. Heart rate and sinus arrhythmia gap were used to express vagal activity indirectly. N-methylhistamine was determined in urine samples collected in periods of 4 hours between the measurements. In group I, overall N-methylhistamine excretion was on a higher level than in both other groups, and was significantly higher overnight. Parasympathetic stimulation did not seem of importance to the increase of airflow obstruction at night.This study was supported by a grant from the Nederlands Astma Fonds. 相似文献
45.
46.
N. M. van Schoor D. L. Knol C. A. W. Glas R. W. J. G. Ostelo A. Leplège C. Cooper O. Johnell P. Lips 《Osteoporosis international》2006,17(4):543-551
Introduction Vertebral deformities are a common consequence of osteoporosis and are known to decrease quality of life. The Qualeffo–41
is a quality-of-life questionnaire especially developed for measuring quality of life in patients with vertebral deformities.
It consists of 41 questions arranged in five domains: pain, physical function, social function, general health perception,
and mental function. The objectives of this study were: (1) to develop a shorter version of the Qualeffo–41 by removing redundant
questions; and (2) to investigate the scale characteristics, reliability, and validity of this shorter version.
Methods The study was performed using data from the Qualeffo validation study and the Multiple Outcomes of Raloxifene Evaluation (MORE)
study. The analyses were performed in patients with vertebral deformities (n=579). Factor analysis on polychoric correlations and an item response theory (IRT) model, i.e., the generalized partial credit
model (GPCM), were used to create a shorter version of Qualeffo–41. Using GPCM, scoring weights were computed for all items.
Results Three items were removed from the data set because of too many missing values. Factor analysis identified three instead of
five domains: (1) pain, (2) physical function, and (3) mental function. Five items had factor loadings <0.4 and were not included
in the GPCM. After excluding several items, the domains pain (four items), physical function (18 items), and mental function
(nine items) showed a good, reasonable, and excellent fit, respectively. This indicates that the mental function domain and
the pain domain are more unidimensional than the physical function domain. All three domains showed a very high correlation
(r ≥0.95) with the corresponding domains of the Qualeffo–41.
Conclusions Qualeffo–31 was developed, consisting of three domains with a reasonable to excellent fit to the GPCM. Although the fit to
the GPCM supports the construct validity of the Qualeffo–31, validation in a new study should be performed before using it
in practice. 相似文献
47.
Visual Functioning Questionnaire: reevaluation of psychometric properties for a group of working-age adults. 总被引:3,自引:0,他引:3
Maaike Langelaan Ruth M A van Nispen Dirk L Knol Annette C Moll Michiel R de Boer Bill Wouters Ger H M B van Rens 《Optometry and vision science》2007,84(8):775-784
PURPOSE: The Visual Functioning Questionnaire (VFQ-25) is one of the most widely used measures of vision-related quality of life. However, the questionnaire does not meet some psychometric quality criteria. The objectives of this study were first to obtain the factor structure of the VFQ-25, and second, to obtain interval scales by Rasch analysis. METHODS: The questionnaire was administered to 129 visually impaired adults (mean age 42.1 years; range 21 to 67 years). First, the items of the VFQ-25 were subjected to an exploratory factor analysis with Promax rotation. Next, we performed a separate Rasch analysis on each factor. We examined step thresholds and goodness of fit statistics of the items. Finally, we examined differential item functioning. RESULTS: Factor analysis indicated four factors: Near Activities, Distance Activities and Mobility, Mental Health and Dependency, and Pain and Discomfort. They accounted for 46.37% of the total variance. Most items showed some degree of disordering. After collapsing response categories, all items showed ordered thresholds. The Near Activities domain showed excellent fit, whereas the Distance Activities and Mobility domain, the Mental Health and Dependency domain, and the Pain and Discomfort domain had an unsatisfactory fit. There were two items showing uniform differential item functioning. CONCLUSIONS: The four-factor structure of the VFQ-25 largely confirms the structure of the questionnaire. However, the results of this study suggest that modifications of the original VFQ-25 structure are necessary. 相似文献
48.
Jurriaan P Oudhoff Danielle RM Timmermans Martin Rietberg Dirk L Knol Gerrit van der Wal 《BMC health services research》2007,7(1):32
Background
Problematic waiting lists in public health care threaten the equity and timeliness of care provision in several countries. This study assesses different stakeholders' views on the acceptability of waiting lists in health care, their preferences for priority care of patients, and their judgements on acceptable waiting times for surgical patients. 相似文献49.
C B Kartasasmita O Rosmayudi B G Kartasasmita K Knol M Collombijn 《Paediatrica Indonesiana》1990,30(1-2):31-41
Although the hazards of smoking is well known, the number of smokers among high school students is still high. There are many factors influencing these students to start smoking. This study was conducted to discover the size of the population of smokers among high school students is still high. There are many factors influencing these students to start smoking. This study was conducted to discover the size of the population of smokers among high school students, their smoking behaviour, and what factors might be associated as risk factors. Questionnaires were filled by 1627 respondents between 12 and 22 years of age of which 955 (58.7%) are boys and 672 (41.3%) are girls. Among all male respondents there were found 622 (86.2%) experimental smokers; among all the girls there were only 99 (13.7%) experimental smokers. From the total number of experimental smokers, 377 (95.2%) boys and 19 (4.8%) girls eventually became smokers. One hundred and seventeen (16.2%) students tried smoking before 13 years old, 65 of these students became smokers. This study found that socio-economic status, parents, friends, and siblings who smoked, and social environment, have significant influence on high school students' smoking habits. To prevent and lower the number of smokers among students in high schools, health and smoking education must be started in the schools as early as possible. 相似文献
50.