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991.
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
992.
M Atasoy† C Aliagaoglu‡ O Sahin§ M Ikbal¶ N Gursan§ 《Journal of the European Academy of Dermatology and Venereology》2006,20(3):337-340
Linear atrophoderma of Moulin has a distinctive disease pattern characterized by hyperpigmented atrophoderma and was described originally in 1992. It follows the line of Blaschko, and occurs without preceding inflammation, subsequent induration or scleroderma. The lesions usually develop during childhood or adolescence, and the prognosis is good. The diagnosis is made clinically and histopathologically. In our 18-year-old male patient, there were atrophic plaques unilaterally located on the trunk and arm, and white discoloration on all finger nails. Histopathological examination revealed epidermal atrophy together with disruption of collagen fibres. 相似文献
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996.
Ganapathy A Prasad Kenneth K Wang Lori S Lutzke Jason T Lewis Schuyler O Sanderson Navtej S Buttar Louis M Wong Kee Song Lynn S Borkenhagen Lawrence J Burgart 《Clinical gastroenterology and hepatology》2006,4(2):173-178
BACKGROUND & AIMS: The aim of this study was to assess the validity of frozen section analysis of endoscopic mucosal resection (EMR) specimens from Barrett's esophagus as compared with permanent sections for the detection of neoplasia. Frozen sections help to give immediate feedback for surgical procedures. It has not been determined whether EMR can be adequately interpreted by using frozen sections to aid endoscopists in completely resecting neoplastic lesions. METHODS: EMR specimens from Barrett's esophagus with high-grade dysplasia (HGD) and/or carcinoma were tested by frozen section. Pathologists evaluated EMR specimens for the depth of invasion as well as the appearance of clear margins of resection. The kappa statistic was calculated to assess the degree of agreement between the frozen section and permanent section diagnoses. RESULTS: Twenty-three consecutive patients underwent 30 EMRs with frozen section diagnosis. Frozen section revealed a carcinoma in 7 specimens (23%) and dysplasia in 20 (66%). Permanent sections found carcinoma in 8 specimens (26%), dysplasia in 19 specimens (63%), and normal or nondysplastic Barrett's esophagus in the remainder. The kappa statistic for the depth of invasion of EMR specimens was 0.93 (near perfect agreement). The kappa statistic for the margins of the EMR specimens was 0.80 (excellent agreement). CONCLUSIONS: This study indicated that frozen section analysis of esophageal EMR specimens is valid as compared with permanent section. This technique might allow rapid evaluation about the degree and depth of involvement of cancers. This allows physicians to make decisions regarding further therapy if margins are involved or decrease the use of EMR for histologically benign-appearing lesions. 相似文献
997.
Hirotsugu Yamada MD PhD Zoran B. Popovic MD PhD David O. Martin MD MPH Kenneth C. Civello MD MPH Don W. Wallick PhD 《Heart rhythm》2006,3(6):722-727
BACKGROUND: Coupled pacing (CP), which consists of delivering a premature electrical stimulation to the heart after the effective refractory period of ventricular activation, is a novel method for controlling ventricular rate during atrial fibrillation (AF). It also has been established that CP improves pump function by enhancing external cardiac work and myocardial efficiency. OBJECTIVE: The purpose of the present study was to determine if two time delays for CP (short and long) would result in similar improvements in ventricular function. METHODS: In a canine model, we applied CP at two time delays (CP-S and CP-L) during two stages: sinus rhythm (SR) and acute AF. The cardiac responses to CP during SR served as the nontachycardic and nondepressed control. During both rhythms, we shortened the coupling interval until we obtained maximal contractility, designated CP-S. Next, we increased the delay until we started to see a measurable secondary contraction (left ventricular pressure development of approximately 20 mmHg). These longer delays were designated CP-L. RESULTS: Our results showed that the ventricular rate of intrinsic activation (VRIA) remained decreased despite prolongation of the time delay of CP during both AF and SR. Also, both delays of CP increased left ventricular systolic pressure (LVSP) and dLVP/dt, which are indices of myocardial contractility. In contrast, CP increased external cardiac work only during AF. Prolonging this time delay did not markedly decrease the improvement in external cardiac work. Myocardial O(2) consumption (MVO(2)) did not significantly change as the result of CP during either SR or AF. Finally, myocardial efficiency improved during AF as the result of CP at both time delays. CONCLUSIONS: In conclusion, shorter time delays for CP increased contractile strength during both SR and AF. However, extending the time delay of CP had minimal effects on diminishing the improved ventricular pump function and energetics that resulted from CP during AF. Thus, the maximal enhancement of myocardial contractility via CP-S was not needed to maintain the improved ventricular function during acute AF when CP is applied. 相似文献
998.
O. Yamasaki A. Tristan T. Yamaguchi M. Sugai G. Lina M. Bes F. Vandenesch J. Etienne 《Clinical microbiology and infection》2006,12(6):585-588
Exfoliative toxin D (ETD) was identified recently as a new exfoliative toxin serotype. Like other exfoliative toxins, ETD induces intra-epidermal cleavage through the granular layer of the epidermis of neonatal mice. The distribution of ETD production was investigated in Staphylococcus aureus isolates from infected and colonised patients in France. The etd gene was found in 55 (10.5%) of 522 isolates tested. Isolates responsible for bullous impetigo and generalised staphylococcal scalded skin syndrome did not harbour etd, but etd was significantly more frequent in isolates causing cutaneous abscesses and furuncles. Most etd- and Panton-Valentine leukocidin-positive strains belonged to the clone of community-acquired methicillin-resistant S. aureus spreading currently throughout France. 相似文献
999.
The aim of the study was to assess the effect of academic stress on periodontal health. The experimental group consisted of 22 final year dental students preparing for a major final BDS examination. The control group was made of 29 first year dental clinical students who were not preparing for any examination. Informed consents were obtained from all the students who participated in the study. The study was double blind as the examiners and the students were not aware of the aim of the study at the examination stage. The baseline measurements of Oral Hygiene Index (OHI) and Gingival Index (GI) were done 6 weeks prior to the commencement of the final BDS examination for both the experimental and the control groups. Statistical significant differences were observed in the two indices at final reading, between experimental and control groups while the baseline scores for the indices revealed no statistical significant differences. The results indicate that non-demonstrable factors like psychosocial stress represent a risk indicator for periodontal disease and these should be addressed in periodontal patients before and during treatment. 相似文献
1000.
Jin-Seon Song Francis K Mante William J Romanow Syngcuk Kim 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,102(6):809-815
OBJECTIVE: To evaluate the chemical composition and crystalline structures of Portland cement, gray ProRoot MTA (gray MTA), white ProRoot MTA (white MTA), and gray MTA-Angelus. STUDY DESIGN: X-ray diffraction analysis was used to identify and characterize crystalline phases, and energy dispersive x-ray spectrometer was used to determine the chemical composition of the test materials. Both powder form and set form were examined. RESULTS: The crystalline structure and chemical composition of gray and white MTA were similar except for the presence of iron in gray MTA. Both were composed mainly of bismuth oxide and calcium silicate oxide. Portland cement was composed mainly of calcium silicate oxide and did not contain bismuth oxide. Gray MTA-Angelus had a lower content of bismuth oxide than ProRoot MTA. There were no noticeable differences in the chemical composition and crystalline structures between the powder and set forms of any of the material tested. CONCLUSION: Portland cement differed from the MTA by the absence of bismuth ions and presence of potassium ions. Gray MTA contained a significant amount of iron when compared with white MTA. In addition, gray MTA-Angelus had a lower content of bismuth oxide than ProRoot MTA. 相似文献