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31.
Yong Jun Choi Byung Joo Lee Hyun Chae Lim Yoon-Sok Chung 《Journal of clinical densitometry》2009,12(4):450-455
In this study, the authors compared bone mineral density (BMD) determined using GE Lunar iDXA and Prodigy and derived cross-calibration equations for the 2 devices in Korean adults. One hundred subjects (66 women and 34 men) participated in this study. Bone mineral density of spine and femur was measured by iDXA and Prodigy dual-energy X-ray absorptiometry (GE Lunar, Madison, WI). Subjects were divided into 3 groups. The first group (30 subjects) was scanned twice using Prodigy for precision testing and then once using iDXA. The second group (30 subjects) was scanned twice using iDXA and then once using Prodigy. Cross-calibration equations were derived using these results. The derived equations were tested in the third group (40 subjects). Predicted values from calculations based on Prodigy findings were compared with measured iDXA data. A significant difference was found between the BMD determined using the 2 devices (p < 0.001). However, linear regression analysis showed a high level of agreement between the two (r2 from 0.984 to 0.994, p < 0.001). Bland-Altman analysis revealed no significant correlations between Prodigy and iDXA. Cross-calibration equations decreased systematic errors between Prodigy and iDXA by 0.4% at the spine, 0.8% at the femoral neck, and 0.1% at the total femur. A high level of agreement was found between Prodigy and iDXA in Korean adults. Cross-calibration equations proved reliable based on comparisons of measured and calculated BMD values. 相似文献
32.
1,25‐Dihydroxyvitamin D Alone Improves Skeletal Growth,Microarchitecture, and Strength in a Murine Model of XLH,Despite Enhanced FGF23 Expression 下载免费PDF全文
Eva S Liu Janaina S Martins Adalbert Raimann Byongsoo Timothy Chae Daniel J Brooks Vanda Jorgetti Mary L Bouxsein Marie B Demay 《Journal of bone and mineral research》2016,31(5):929-939
X‐linked hypophosphatemia (XLH) is characterized by impaired renal tubular reabsorption of phosphate owing to increased circulating FGF23 levels, resulting in rickets in growing children and impaired bone mineralization. Increased FGF23 decreases renal brush border membrane sodium‐dependent phosphate transporter IIa (Npt2a) causing renal phosphate wasting, impairs 1‐α hydroxylation of 25‐hydroxyvitamin D, and induces the vitamin D 24‐hydroxylase, leading to inappropriately low circulating levels of 1,25‐dihydroxyvitamin D (1,25D). The goal of therapy is prevention of rickets and improvement of growth in children by phosphate and 1,25D supplementation. However, this therapy is often complicated by hypercalcemia and nephrocalcinosis and does not always prevent hyperparathyroidism. To determine if 1,25D or blocking FGF23 action can improve the skeletal phenotype without phosphate supplementation, mice with XLH (Hyp) were treated with daily 1,25D repletion, FGF23 antibodies (FGF23Ab), or biweekly high‐dose 1,25D from d2 to d75 without supplemental phosphate. All treatments maintained normocalcemia, increased serum phosphate, and normalized parathyroid hormone levels. They also prevented the loss of Npt2a, α‐Klotho, and pERK1/2 immunoreactivity observed in the kidneys of untreated Hyp mice. Daily treatment with 1,25D decreased urine phosphate losses despite a marked increase in bone FGF23 mRNA and in circulating FGF23 levels. Daily 1,25D was more effective than other treatments in normalizing the growth plate and metaphyseal organization. In addition to being the only therapy that normalized lumbar vertebral height and body weight, daily 1,25D therapy normalized bone geometry and was more effective than FGF23Ab in improving trabecular bone structure. Daily 1,25D and FGF23Ab improved cortical microarchitecture and whole‐bone biomechanical properties more so than biweekly 1,25D. Thus, monotherapy with 1,25D improves growth, skeletal microarchitecture, and bone strength in the absence of phosphate supplementation despite enhancing FGF23 expression, demonstrating that 1,25D has direct beneficial effects on the skeleton in XLH, independent of its role in phosphate homeostasis. © 2016 American Society for Bone and Mineral Research. 相似文献
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Understanding the electronic band structure and density of states (DOS) of a material and their relationship to the associated electronic transport properties is the starting point for optimizing the performance of a device and its technological applications. In a hydrogenated Zn0.8Co0.2O (ZnCoO:H) film with an inverted thin-film transistor structure, we found ambipolar behavior, which is shown in many field-effect devices based on graphene, graphene nanoribbons, and organic semiconductors. In this study, to obtain information on the DOS of ZnCoO:H to explain the ambipolar behavior in terms of the carrier density and type, resistivity and magnetoresistance measurements of a ZnCoO:H film were performed at 5 K. Our proposed DOS representation of ZnCoO:H explains qualitatively the experimental observations of carrier density modulation and ambipolar behavior. First-principles calculations of the DOS of ZnCoO:H were in good agreement with the proposed DOS representation. Through a comparison of first-principles calculations and experimental data, evidence for the existence of Co–H–Co in ZnCoO:H is suggested.Ambipolar behavior in a hydrogenated Zn0.8Co0.2O (ZnCoO:H) film is investigated via resistivity and magnetoresistance measurements and first-principles calculations of the DOS. Evidence for the existence of Co–H–Co in ZnCoO:H is suggested. 相似文献
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Jung Eui-Gil Han Kook-Il Kwon Hyun-Jung Patnaik Bharat Bhusan Kim Wan-Jong Hur Gang Min Nam Kung-Woo Han Man-Deuk 《Archives of pharmacal research》2015,38(6):973-983
Archives of Pharmacal Research - Sappanchalcone, a bioactive flavonoid isolated from the heartwood of Caesalpinia sappan L. possesses anti-inflammatory effects. We studied the efficacy of... 相似文献
39.
Low grade gastric mucosa associated lymphoid tissue lymphoma:Treatment strategies based on 10 year follow-up 总被引:2,自引:0,他引:2
Lee SK Lee YC Chung JB Chon CY Moon YM Kang JK Park IS Suh CO Yang WI 《World journal of gastroenterology : WJG》2004,10(2):223-226
AIM: To deduce strategic guidelines of gastric mucosa associated lymphoid tissue lymphoma (MALTOMA) by evaluating the long-term outcome of patients in respect to various treatment modalities. METHODS: A total of 55 patients with MALTOMA from May 1992 to August 2002 were retrospectively reviewed. RESULTS: Complete remission was obtained in 24 (82.8%) of 29 patients treated with anti Helicobacter pylori (H pylori) regimen only. The duration to reach complete remission was 12 months (85 percentile, 2-33 months). Five patients showed complete remission with radiation therapy (26-86 months). Two of them were H pylori treatment failure cases. CONCLUSION: H pylori eradication is an effective primary treatment option for low grade MALTOMA and radiation therapy could be considered in patients with no evidence of H pylori infection or who do not respond to H pylori eradication therapy 12 months after successful eradication. 相似文献
40.
Noninvasive transcutaneous low frequency ultrasound enhances thrombolysis in peripheral and coronary arteries 总被引:7,自引:0,他引:7
Siegel RJ Atar S Fishbein MC Brasch AV Peterson TM Nagai T Pal D Nishioka T Chae JS Birnbaum Y Zanelli C Luo H 《Echocardiography (Mount Kisco, N.Y.)》2001,18(3):247-257
Previous studies have shown that external ultrasound with low frequencies and high intensities can enhance thrombolytic drug-induced clot dissolution during in vitro experiments. In this series of studies, we evaluated the efficacy of peripheral and coronary thrombolysis in vivo in animals by using noninvasive transcutaneous ultrasound combined with thrombolytic drugs (streptokinase and tPA) and/or microbubbles agents (dodecafluoropentane [DDFP] and perfluorocarbon-exposed sonicated dextrose albumin [PESDA]). Thrombotic occlusions were induced in 74 rabbit iliofemoral arteries and 24 canine left anterior descending (LAD) coronary arteries in this in vivo study. By using the combination of transcutaneous ultrasound and streptokinase, the angiographic patency rate in rabbit iliofemoral arteries was higher (56%-100%) than with ultrasound (6%; P < or = 0.0036) and streptokinase alone (6%; P < or = 0.0012). Also, with transcutaneous ultrasound and microbubbles, the angiographic patency rates were 76%-100% as compared with ultrasound alone (0%, P < or = 0.0003) or microbubbles alone (9%, P < or = 0.0001). In the canine study of acute myocardial infarction, thrombolysis in myocardial infarction (TIMI) grade flow at 90 minutes in the tPA alone group was 0.92 +/- 1.4 as compared with 2.42 +/- 1.9 in the tPA plus transthoracic ultrasound group (P = 0.006). There was much improved reperfusion with tPA plus ultrasound as compared with tPA alone. In vivo animal studies demonstrate that noninvasive transcutaneous ultrasound can greatly enhance the effect of clot dissolution with thrombolytic drugs and/or microbubbles, and has the potential for clinical application as an adjunctive method to improve arterial thrombolysis. 相似文献