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1.
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
2.
T Gloudemans I Pospiech L T Van Der Ven C J Lips H Schneid W Den Otter J S Sussenbach 《Cancer research》1992,52(23):6516-6521
Previously we have shown that expression of the insulin-like growth factor II (IGF-II) gene in 36 normal smooth muscle tissues (myometria) and 26 benign smooth muscle tumors (leiomyomas) was detectable by Northern blot analysis but that the RNA levels were low. In 9 of 20 malignant smooth muscle tumors (leiomyosarcomas) IGF-II gene expression was also low or absent, while in 11 of 20 the IGF-II gene was abundantly expressed. In 32 of these tissues we have now studied the DNA methylation state of the IGF-II gene. For the analysis of overall methylation of the gene the restriction endonucleases HpaII and MspI were used. In normal smooth muscle and in leiomyomas the IGF-II gene appeared to be methylated. In leiomyosarcomas with low IGF-II gene expression the DNA was partly demethylated. In leiomyosarcomas with abundant IGF-II gene expression overall methylation of the DNA tended to be low. In addition, we have studied the methylation state of one particular CpG site in the IGF-II gene with the restriction endonuclease AvaII. The results of the latter analysis confirm the analysis with HpaII and MspI. In conclusion, in malignant smooth muscle tumors the data indicate an inverse correlation between CpG methylation and expression of the IGF-II gene. 相似文献
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5.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
6.
P. Lips MD C. Cooper D. Agnusdei F. Caulin P. Egger O. Johnell J. A. Kanis U. Liberman H. Minne J. Reeve J. Y. Reginster M. C. de Vernejoul I. Wiklund 《Osteoporosis international》1997,7(1):36-38
The morbidity of osteoporosis is caused by fractures. Vertebral fractures lead to pain and disability and a decrease in quality of life. A Working Party of the European Foundation for Osteoporosis has developed a specific questionnaire for patients with established vertebral osteoporosis. This questionnaire is intended for use in clinical trials. The questionnaire consists of questions and visual analogue scales in the following domains: pain, activities of daily living, jobs around the house, mobility, leisure and social activities, general health perception and mood. The questionnaire has been translated from English into French, German, Italian, Hebrew, Swedish and Dutch. The questionnaire is currently being validated in a multicentre study involving patients with stable osteoporosis and control subjects. Preliminary results indicate that the reproducibility is sufficient and that the questionnaire is able to discriminate between patients with vertebral osteoporosis and control subjects. 相似文献
7.
Results of a double blind study of 89-strontium therapy of skeletal metastases of prostatic carcinoma 总被引:5,自引:0,他引:5
Klaus Buchali Hans-Jacob Correns Michael Schuerer Dietmar Schnorr Hildegard Lips Karin Sydow 《European journal of nuclear medicine and molecular imaging》1988,14(7-8):349-351
Forty-nine patients were treated with either 3×75 MBq 89Sr or saline as placebo. Analysis of results 1 to 3 years after therapy revealed the ineffectiveness of 89Sr to relieve pain from metastases. Unexpectedly, a higher survival rate was found after Sr application (46% vs 4% after 2 years). Covariate analysis underlines the effect of 89Sr therapy on life expectation. 相似文献
8.
M J Jongen S Kuiper W J van der Vijgh P Lips J C Netelenbos 《Zeitschrift für klinische Chemie und klinische Biochemie》1988,26(1):25-28
Technical improvements have been applied to reduce the time required for the determination of calcidiol and calcitriol in serum or plasma. The modifications include the use of Sep-Pak C18 cartridges for the extraction of calciol metabolites from serum instead of a classical liquid/liquid extraction, a considerable shortening of the HPLC purification time compared with our previously described method, and the application of HPLC with UV detection at 254 nm of calcidiol as an alternative to the usual competitive protein binding methods. In none of the 199 samples where calcidiol was determined by HPLC did we observe a detectable peak of ercalcidiol. Quantitation of calcidiol by HPLC and competitive protein binding was compared in 5 series of assays. The correlation between the two methods was 0.99. The average slope of the linear regression line when the HPLC values were plotted versus the competitive protein binding values was 1.14. The average intercept was 0.19 nmol/l. The mean within-run coefficient of variation for calcidiol in these series was 5% for the competitive protein binding method, and 4% for HPLC method. Between-run coefficients of variation were 6% and 12% for the competitive protein binding and for the HPLC method, respectively. Within-run and between-run coefficients of variation for calcitriol were 6% and 15%, respectively. 相似文献
9.
PL Macken FRACO FRACS CJ Pavlin FRCS R Tuli MD GE Trope PhD FRCS 《Clinical & experimental ophthalmology》1995,23(3):217-220
Background: Spherophakia is an uncommon diagnosis. This is the first case report of spherophakia evaluated by ultrasound biomicroscopy.
Methods: Ultrasound biomicroscopy is a new diagnostic technique developed by one of the authors and provides images with microscopic resolution of the anterior segment. A patient with spherophakia was evaluated by ultrasound biomicroscopy (Zeiss-Humphrey, 50MHz) before and after YAG laser iridotomy.
Results: Ultrasound biomicroscopic assessment revealed a shallow anterior chamber, a very steep anterior lens curvature, iridolenticular contact, elongated zonules, and an increased distance between the lens equator and the ciliary processes. Angle closure glaucoma was due to a pupil block mechanism. The pupil block was relieved by YAG laser iridotomy.
Conclusions: Ultrasound biomicroscopy is a useful technique to confirm the diagnosis of spherophakia. The pupil block in spherophakia is relieved by YAG laser iridotomy. 相似文献
Methods: Ultrasound biomicroscopy is a new diagnostic technique developed by one of the authors and provides images with microscopic resolution of the anterior segment. A patient with spherophakia was evaluated by ultrasound biomicroscopy (Zeiss-Humphrey, 50MHz) before and after YAG laser iridotomy.
Results: Ultrasound biomicroscopic assessment revealed a shallow anterior chamber, a very steep anterior lens curvature, iridolenticular contact, elongated zonules, and an increased distance between the lens equator and the ciliary processes. Angle closure glaucoma was due to a pupil block mechanism. The pupil block was relieved by YAG laser iridotomy.
Conclusions: Ultrasound biomicroscopy is a useful technique to confirm the diagnosis of spherophakia. The pupil block in spherophakia is relieved by YAG laser iridotomy. 相似文献
10.