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991.
The key to effective treatment of osteoporosis is early detection; however, the disease in perimenopausal women is frequently undiagnosed. To assess the utility of quantitative ultrasound (QUS) at the calcaneus in perimenopausal women, broadband ultrasound attenuation (BUA); speed of sound (SOS); quantitative ultra-sound index (QUI), an algorithm of BUA and SOS; and bone mineral density by dual X-ray absorptiometry (DXA) of the posteroanteiror spine, femoral neck, and total hip were measured in 420 women (ages 45-55 yr). Thirty (7.1%) of the women were found to be osteoporotic by DXA. All QUS measurements were predictors of osteoporosis. QUS values did not differ between postmenopausal women on estrogen replacement therapy (ERT) and those not on ERT. There were no differences among BUA, SOS, and QUI in the area under the receiver operating characteristic curves for predicting osteoporotic vs nonosteoporotic cases. At a QUI of 89, ultrasound had an 80% sensitivity for the diagnosis of osteoporosis, but only a 74% specificity. The use of QUS in perimenopausal women will facilitate the identification of women with osteoporosis. However, the high false-positive rate (26%) limits the utility of QUS as the sole diagnostic technique on which to base therapeutic decisions. Nevertheless, low QUS measurements may provide a means for targeting those women who would benefit most from more extensive evaluation (e. g., DXA). 相似文献
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Growth of a bonelike apatite on chitosan microparticles after a calcium silicate treatment 总被引:1,自引:0,他引:1
Bioactive chitosan microparticles can be prepared successfully by treating them with a calcium silicate solution and then subsequently soaking them in simulated body fluid (SBF). Such a combination enables the development of bioactive microparticles that can be used for several applications in the medical field, including injectable biomaterial systems and tissue engineering carrier systems. Chitosan microparticles, 0.6mum in average size, were soaked either for 12h in fresh calcium silicate solution (condition I) or for 1h in calcium silicate solution that had been aged for 24h before use (condition II). Afterwards, they were dried in air at 60 degrees C for 24h. The samples were then soaked in SBF for 1, 3 and 7 days. After the condition I calcium silicate treatment and the subsequent soaking in SBF, the microparticles formed a dense apatite layer after only 7 days of immersion, which is believed to be due to the formation of silanol (Si-OH) groups effective for apatite formation. For condition II, the microparticles successfully formed an apatite layer on their surfaces in SBF within only 1 day of immersion. 相似文献
996.
Local functions for FMRP in axon growth cone motility and activity-dependent regulation of filopodia and spine synapses 总被引:3,自引:0,他引:3
Antar LN Li C Zhang H Carroll RC Bassell GJ 《Molecular and cellular neurosciences》2006,32(1-2):37-48
Genetic deficiency of the mRNA binding protein FMRP results in the most common inherited form of mental retardation, Fragile X syndrome. We investigated the localization and function of FMRP during development of hippocampal neurons in culture. FMRP was distributed within granules that extended into developing axons and growth cones, detectable at distances over 300 microm from the cell body. In mature cultures, FMRP granules were present in both axons and dendrites, with pockets of higher concentrations appearing intermittently, along distal axon segments and near synapses. MAP1b mRNA, a known FMRP target, was also localized to axon growth cones. Morphometric analysis of growth cones from the FMR1 KO revealed both excess filopodia and reduced motility. At later stages during synapse formation, FMR1 KO neurons exhibited excessive filopodia and long spines along dendrites, yet there was a marked decrease in the density of spine-like protrusions juxtaposed to presynaptic terminals. In contrast, there was no difference in the density of shaft synapses between FMR1 KO and WT. Brief depolarization of WT neurons resulted in increased numbers of filopodia and spine synapses, whereas no additional morphologic changes were observable in dendrites of FMR1 KO neurons that already had increased density of filopodia-spines. These findings suggest that alterations in the regulation of axonal growth and innervation in FMR1 KO neurons may contribute to the dendritic and spine pathology in Fragile X syndrome. This work has broader implications for understanding the role of mRNA binding proteins in developmental and protein-synthesis-dependent plasticity. 相似文献
997.
Ivan C. Rokos William J. French William J. Koenig Samuel J. Stratton Beverly Nighswonger Brian Strunk Jackie Jewell Ehtisham Mahmud James V. Dunford Jon Hokanson Stephen W. Smith Kenneth W. Baran Robert Swor Aaron Berman B. Hadley Wilson Akinyele O. Aluko Brian W. Gross Paul S. Rostykus Angelo Salvucci Vishva Dev Spencer B. King 《JACC: Cardiovascular Interventions》2009,2(4):339-346
998.
Sema Aydogdu Levent Midyat Murat Cakir Gokhan Tumgor Hasan Ali Yuksekkaya Masallah Baran Cigdem Arikan Funda Ozgenc Rasit Vural Yagci 《Digestive diseases and sciences》2009,54(10):2183-2187
We sought to analyze the long-term growth in children with celiac disease (CD) as well as the association of height and weight
SD score at the end of 4 years with the demographic and clinical presentation at initial admission. Thirty-four children with
CD were enrolled in the study and followed for at least 4 years. Patients were divided into three groups (Group 1: patients
≤5 years old, Group 2: patients 5–10 years old, and Group 3: patients >10 years, at the time of diagnosis). Patients’ charts
were reviewed for demographic and clinical features at initial admission. Anthropometric measurements at initial admission,
at 6th months, and 1st, 2nd, 3rd, and 4th years were recorded. Gluten-free diet led to rapid increase in weight SD and height
SD score in patients ≤5 years old at the time of diagnosis (Group 1). Increment in height SD score was the highest in patients
5–10 years old (Group 2) at the end of 4 years. A negative correlation was found between age at the time of diagnosis and
weight and height SD score at the end of 4 years (r = −0.503, P = 0.03 and r = −0.554, P = 0.01). Multiple regression analysis revealed that height SD score at the end of the 4 years was associated with age at
the time of diagnosis. The other factors had no effect on the weight and height SD score at the end of 4 years. Early diagnosis
and good adhesion to a gluten-free diet are essential for long-term growth in CD. Celiac societies and the mass media must
expand an effort to educate the community regarding the symptoms of the disease. 相似文献
999.
Eyup Hazan Mehmet Guzeloglu Nejat Sariosmanoglu Baran Ugurlu Vehip Keskin Nurettin Unal 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2009,36(3):252-254
Blunt thoracoabdominal trauma is most often caused by high-velocity motor-vehicle accidents or by falls from a height. The clinical spectrum of cardiac injuries arising from this type of trauma varies from myocardial contusion to valvular rupture. Intracardiac valvular rupture is rarely observed, and few cases have been reported. The youngest of the patients in cases reported to date was 6 years of age. Here we report the case of a 2½year-old child, who sustained mitral valve insufficiency due to isolated rupture of the posterior mitral papillary muscle, which developed after a domestic accident.Key words: Child, mitral valve/injuries/surgery, mitral valve insufficiency, papillary muscles/injuries, rupture, thoracic injuries/complications, wounds, nonpenetratingBlunt thoracoabdominal trauma is most often caused by high-velocity motor-vehicle accidents or by falls from a height,1 and the clinical spectrum of cardiac injuries arising from this type of trauma varies from myocardial contusion to aortic rupture. Intracardiac valvular rupture is rarely observed with this type of trauma, and few cases have been reported. 相似文献
1000.