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61.
Newcombe PA Sheffield JK Juniper EF Marchant JM Halsted RA Masters IB Chang AB 《Chest》2008,133(2):386-395
BACKGROUND: Chronic cough affects at least 7% of children, and the impact of this on families is significant. Although adult cough-specific quality-of-life (QOL) instruments have been shown to be a useful cough outcome measure, no suitable cough-specific QOL for parents of children with chronic cough exists. This article compares two methods of item reduction (clinical impact and psychometric) and reports on the statistical properties of both QOL instruments. METHOD: One hundred seventy children (97 boys and 73 girls; median age, 4 years; interquartile range, 3 to 7.25 years) and one of their parents participated. A preliminary 50-item parent cough-specific QOL (PC-QOL) questionnaire was developed from conversations with parents of children with chronic cough (ie, cough for > 3 weeks). Parents also completed generic QOL questionnaires (eg, Pediatric Quality of Life Inventory, version 4.0 [PedsQL4.0] and the 12-item Short Form Health Survey, version 2 [SF-12v2]). RESULTS: The clinical impact and psychometric method of item reduction resulted in 27-item and 26-item PC-QOL questionnaires, respectively, with approximately 50% of items overlapping. Internal consistency among the final items from both methods was excellent. Some evidence for concurrent and criterion validity of both methods was established as significant correlations were found between subscales of the PC-QOL questionnaire and the scales of the SF-12v2 and PedsQL4.0 scores. The PC-QOL questionnaire derived from both methods was sensitive to change following an intervention. CONCLUSION: Chronic cough significantly impacts on the QOL of both parents and children. Although the PC-QOL questionnaires derived from a clinical impact method and from a psychometric method contained different items, both versions were shown to be internally consistent and valid. Further testing is required to compare both final versions to objective and subjective cough measures. 相似文献
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《Dental materials》2020,36(1):60-67
ObjectivesThe rapidly increasing use of zirconia-based CAD/CAM multi-layer structures in dentistry calls for a thorough evaluation of their mechanical integrity. This work examines the effect of the multi-layering architecture as well as variations in composition and inclusion of pigments among the layers on the flexural strength of multi-layer zirconias.MethodsA modified 4-point bending test, aided by a Finite Element Analysis (FEA), was used to probe the interfacial strength of 3 classes of yttria-partially-stabilized zirconia: Ultra Translucent Multi-Layer (UTML—5Y-PSZ), Super Translucent Multi-Layer (STML—4Y-PSZ), Multi-Layer (ML—3Y-PSZ). In accord with the size limitation (22-mm height) of CAD/CAM pucks, test samples were prepared in the form of “long” (25 × 2 × 3 mm) and “short” (17.8 × 1.5 × 2 mm) beams. Homogeneous beams (both long and short) were produced from either the Enamel (the lightest shade) or Dentin (the darkest shade) layer, whereas multi-layer beams (short beam only) were obtained by cutting the pucks along their thickness direction, where the material components of various shades were stacked.ResultsThe Enamel and Dentin layers exhibited similar flexural strength for a given material class, with ML amassing the highest strength (800–900 MPa) followed by STML (560–650 MPa) and UTML (470–500 MPa). The 3 classes of multi-layer zirconia showed a trade-off between strength and translucency, reflecting different yttria contents in these materials. The failure stress of the cross-sectional multi-layer beams was, however, ∼30% lower than that of their Enamel or Dentin layer counterparts, regardless of material tested.SignificanceThe weakness of interfaces is a drawback in these materials. Additionally, when measuring strength using short beam flexure, friction between the specimen and supporting pins and accuracy in determining loading span distances may lead to major errors. 相似文献
66.
We compared the growth of 183 children with short stature (≤ 2SD) and 73 children of
normal height at age six who were visiting the Tanaka Growth Clinic. We classified these
short children as suffering from either idiopathic short stature (ISS, n = 119), GH
deficiency (GHD, n = 33) or small-for-gestational-age short stature (SGASS, n = 31) on the
basis of subsequent test results and other factors. We also conducted a retrospective
study of changes in their height, wt and nutritional intake over time. The mean changes in
height SD score from birth to 6 yr were –0.24 SD in normal height children with a normal
birth length and +2.27 SD in normal height children with a low birth length. In short
children, these changes were –1.93 SD for children with ISS, –2.41 SD for those with GHD
and +0.58 for those with SGASS. The mean changes from birth to 6 mo were –0.84 SD, −1.03
SD and +0.38 SD in children with ISS, GHD and SGASS, respectively. The mean change in
height SD score from birth to age 1 yr was –1.07 SD, –1.44 SD and +0.35 SD, respectively.
The decrease in height SD score from birth to 6 mo accounted for 43.5% of the decrease in
height SD score from birth to 6 yr in children with ISS and it accounted for 42.6% of the
decrease in children with GHD. Only 19% of short children bottle-fed well, and 53% fed
poorly, as opposed to 56% and 16% of normal height children who fed well and poorly,
respectively. Post weaning, only 22% of short children ate well, and 56% fed poorly, as
opposed to 53% and 17% of normal height children who fed well and poorly, respectively.
These findings demonstrated that growth failure started from early infancy in ISS and GHD
children. It was suggested that poor nutritional intake in infancy and early childhood was
a partial cause of short stature at age 6. 相似文献
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Christopher Jones Adeel Aqil Susannah Clarke Justin P. Cobb 《Journal of orthopaedics and traumatology》2015,16(3):229-235
BackgroundShort femoral stems for uncemented total hip arthroplasty have been introduced as a safe alternative to traditional longer stem designs. However, there has been little biomechanical examination of the effects of stem length on complications of surgery. This study aims to examine the effect of femoral stem length on torsional resistance to peri-prosthetic fracture.ResultsSynthetic femora implanted with short stems fractured at a significantly higher torque (27.1 vs. 24.2 Nm, p = 0.03) and angle (30.3° vs. 22.3°, p = 0.002) than those implanted with long stems. Fracture patterns of the two groups were different, but showed remarkable consistency within each group. These characteristic fracture patterns were closely replicated in the pair of cadaveric femora.ConclusionsThis new short-stemmed press-fit femoral component allows more femoral flexibility and confers a higher resistance to peri-prosthetic fracture from torsional forces than long stems. 相似文献
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